HomeMy WebLinkAbout879 RESOLUTION NO. 7 2
A RESOLUTION of the City of Kent,
Washington, adopting as City Policy the
plans, procedures and objectives of Water
Systems Plan of October 10 , 1979 .
WHEREAS , URS , consulting engineers , have prepared
a Water Systems Plan for the Water Department of the City of
Kent, said plan being promulgated October 10 , 1979 .
WHEREAS , said Water Systems Plan provides for an
orderly expansion and improvement of the plants and facilities
of the Water Department of the City of Kent, NOW, THEREFORE
THE CITY COUNCIL OF THE CITY OF KENT, WASHINGTON,
DO HEREBY RESOLVE AS FOLLOWS :
Section 1 . The Water Systems Plan for the Water
Department of the City of Kent prepared and promulgated by URS ,
consulting engineers , October 10 , 1979 , be and the same hereby
is adopted as official policy of the City of Kent.
Section 2 . The City Council reserves the right to
establish its own order of priority which may or may not be the
same as those suggested in the Water Systems Plan.
PASSED by the City Council at a regular meeting this
19th day of November , 1979 .
ISABEL HOGAN, MA
ATTEST:
RIE JENSEN, CITY CLERK
AP ROVED AS TO FORM:
ONAI,D E. MIRK, CITY ATTORNE
City of
Water System Plan
Prepared by URS Company
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URS is a multi-disciplinary profes-
sional services company consisting
of engineers, architects, planners,
economists, biologists, and other
professionals with related skills.
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Its objective is to provide excel-
lence in service to meet the needs
of growing communities and the
businesses and industries in these
communities.
URS
Fourth and Vine Building
Seattle, Washington 98121
(206)623-6000 —
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URS
AN INTERNATIONAL PROFESSIONAL SERVICES ORGANIZATION
SEATTLE
URS COMPANY SPO ANE
FOURTH AND VINE BUILDING LAS AS
ALASKA
SEATTLE,WASHINGTON 98121 PORTLAND
TEL: (206)623-6000 SAN FRANCISCO
DENVER
DALLAS
KANSAS CITY
NEW ORLEANS
NEW YORK
October 10, 1979 W SHINNGTON,D.C.
SAN MATEO
HONOLULU
LONDON
Honorable Mayor and City Council
City of Kent
City Hall
Kent, Washington 98031
Dear Mayor and Council Members:
As provided for under terms of the contract for engineering services
between the City of Kent and URS Company, we are herewith submitting
the final Water System Plan as provided for under the agreement.
The studies which have been undertaken over the last several months
have resulted in a water system plan which addresses the needs of the
City of Kent over the next 20 years.
The plan addresses all aspects of water supply including source
development, transmission, storage and distribution. The facilities
called for in this plan are outlined in a phased capital improvement
program which when implemented will assure the City of adequate water
supplies.
Upon your adoption of this plan, it will be submitted along with the
SEPA requirements to King County for the County' s approval and
certification.
We sincerely appreciate the opportunity to be of service to the City
J of Kent on this project. We gratefully acknowledge the valuable
input which has been provided by the Mayor, The City Council and the
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URS
AN INTERNATIONAL PROFESSIONAL SERVICES ORGANIZATION
Honorable Mayor and City Council
October 10, 1979
Page 2
Staff. We sincerely thank you for the opportunity to be of service
to you.
Respectfully submitted,
Walter G. Ramsey, P.E. Jess Abed, P.E. AIP
Senior Vice President Project Engineer
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WATER SYSTEM PLAN
FOR
THE CITY OF KENT
WASHINGTON
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BY
URS COMPANY
SEATTLE , WASHINGTON
OCTOBE R 12, 1 9 7 9
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CITY OF KENT, WASHINGTON
WATER SYSTEM PLAN
ISABEL HOGAN , MAYOR
COUNCIL MEMBERS
WILLIAM CAREY BILL ELLIOTT
LEN MCCAUGHAN JON JOHNSON
GARY JUST JEANE MASTERS
BILLIE JOHNSON
PARTICIPATING CITY STAFF
R. C. CUSHING - CITY ADMINISTRATOR
G. W. ULETT - DIRECTOR OF PUBLIC WORKS
DON E. WICKSTROM - CITY ENGINEER
DON MIRK - CITY ATTORNEY
JAMES HARRIS - PLANNING DIRECTOR
STAN BODEN - WATER SUPERINTENDENT
PROJECT STAFF
URS COMPANY
WALTER G. RAMSEY RICK SCHAEFER
JACK A. LEET DAVID BROWNE
JESS ABED JENNIFER BROWN
CITY OF KENT
WATER SYSTEM PLAN
TABLE OF CONTENTS
Page
I . SUMMARY AND RECOMMENDATIONS . . . . . . . . . . . 1
Summary . . . . . . . . . . . . . . . . 1
Recommendations . . . . . . . . . . . . . . 10
II . INTRODUCTION . . . . . . . . . . . . . . . . 12
Authorization . . . . . . . . . . . . . . . 12
Purpose and Scope . . . . . . . . . . . . . 12
III . PLANNING AREA DESCRIPTION . . . . . . . . . . . . 16
General . . . . . . . . . . . . . . 16
Service Area Boundaries . . . . . . . . 16
History of the Water System . . . . . . . 17
Available Water Resources . . . . . . . . 20
Characteristics of the Service Area . . . . 21
!� Inventory of Related Plans . . . . . . . . . 24
Land Use and Zoning 25
Population Estimates & Projections 26
�] Present Water Use and Projected Demand . . 29
IV. DESCRIPTION OF EXISTING SYSTEM . . . . . . . . . 34
General . . . . . . . . . . . . . . . . 34
Source and Transmission . . . . . . . . . 34
Pressure Zones . . . . . . . . 36
The East Hill System . . . . . . . . . 36
The Valley Sysem . . . . . . . . . . . 39
The West Hill System 40
Recent System Improvements . . . . . . . . . 41
V. HYDRAULIC ANALYSIS AND FIRE DEMANDS . . . . . . . 43
General 43
West Hill System - Lev. 529 Feet 44
West Hill Intermediate System• 46
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Elev. 354. 5 Feet
Low Level System - Elev. 240 Feet 46
East Hill Intermediate System -
Elev. 485 Feet . • 48
East Hill System and Water District
No. 111 - Elev. 590 Feet . . . . . . . . . 49
VI . SOURCE ANALYSIS . . . . . . . . . . . . . . . . 53
Production and Consumption Data . . . . . . 53
Impact of Water Shortage on Water System . . 53
Sources of Additional Supply . . . . . . . . 55
Classification of Sources of Additional
Supply • . . . . . . . 61
Cost Comparison: City of Seattle vs.
City of Kent ' s Sources . 62
Cost Analysis of Other Sources of Supply . . 65
Summary . . . . . . . . . . . . . . . . . . 67
Page
VII . SYSTEM'S FUTURE NEEDS AND ALTERNATIVES
TO MEET THEM: WATER SYSTEM PLAN . . . . . . . 69
General . . . . . . . . . . . . . . . . . 69
Supply Sources . . . . . . . . . . . . . . 69
Transmission Mains . . . . . . . . . . 74
Storage and Pumping Facilities . . . . . . 74
Summary . . . . . . . . . . . . . . . . . 78
VIII. IMPLEMENTATION PROGRAM 80
List of Projects and Cost Estimate 80
Phasing and Scheduling . . . . . . . . . . 82
IX. COMPATIBILITY OF WATER SYSTEM WITH OTHER PLANS . 86
Related Plans
Comprehensive Plan . . . . . . . . . 86
Zoning Plan . . . . . . . . . . . . . 86
Sewerage Plan . . . . . . . . . . . . 87
Adjacent Water Purveyors . . . . . . . . . 87
X. SYSTEM OPERATIONS PROGRAM . . . . . . . . . . . 89
General . . . . . . . . . . . . . . . . . 89
Management and Operation Responsibility. . 90
Preventive Maintenance Program . . . . . . 91
Water Quality Monitoring . . . . . . . . . 94
Cross Connections Control . . . . . . . . 95
Emergency Response . . . . . . . . . . . . 99
XI. DEVELOPERS CRITERIA AND STANDARDS . . . . . . . 121
LIST OF TABLES
TABLE NO. TITLE PAGE
1 Population Estimates and Projections
for Kent ' s Service Area . . . . . . . . 28
2 Service Area Population Projections
byYear . . . . . . . . . . . . . . . . 28
3 Water Consumption Within Kent ' s
Service Area . . . . . . . . . . . . . 30
4 Water Use for July 1979 by Sub-Areas 30
5 Projection of Water Use for July 1980 . . 31
by Sub-Areas
6 Projection of Water Use for July 1985 . . 31
by Sub-Areas
^� 7 Projection of Water Use for July 1990 . . 32
by Sub-Areas
rt.1 8 Projection of Water Use for July 2000 32
by Sub-Areas
9 Cost Summary of Additional Sources
of Supply . . . . . . . . . . . . . . . 68
10 List of Projects and Construction
Schedule . . . . . . . . . . . . . . . 83
11 Water Quality Monitoring Requirements 96
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LIST OF FIGURES
FIGURE N0. TITLE
PAGE
r� 1 Vicinity Map . . . . . . . . . . . . . . 13
2 Service Area Boundaries . . . . . . . . 15
3 Service Area Topography . . . . . . . . 23
4 Demand-Supply Curve . . . . . . . . . 33
5 Valve Inspection Form . . . . . . . . . 93
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I . SUMMARY AND RECOMMENDATIONS
This chapter summarizes the main features of the Water
System Plan and provides a set of recommendations for action by
the City administration.
SUMMARY
The summary will address the following topics:
�1 o The Service Area
I o Pressure Zones
o Sources of Water
o Present and Projected Population
Y� o Present Water Use and Projected Demand
o Supply and Demand Relationship-Water Shortage
o Hydraulic Analysis and Fire Demands
o Sources of Additional Supply
o Cost Comparison of New Sources
o Capital Improvement Program
The Service Area:
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l The City of Kent presently provides water service for
�J an area comprising about 27 square miles in area containing a
J population of about 35,000. The service area is generally
bound by 124th Ave. S.E. on the east, I-5 on the west, S.E.
180th Street on the north and S.E. 277th Street on the south.
The service area is shown in Figure 3 in the report. In terms
of usage, 54% of the water is consumed in the valley system,
36% in the East Hill and 10% in the West Hill.
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Pressure Zones :
The City' s system is divided into three sub-systems
containing five different pressure zones. These are:
East Hill high zone at 590 feet
East Hill low zone at 485 feet
Valley system at 240 feet
West Hill low zone at 354 . 5 feet
West Hill high zone at 529 feet
The boundaries of these pressure zones are outlined on
the attached map.
Sources of Water:
The primary sources of water supplying the City are the Kent
Springs and Clark Springs located about 10 and 14 miles east of
Kent respectively. The Kent Springs source has the capacity to
produce on a continuing basis about 5 . 2 million gallons per day
(mgd) by running the two wells. The Clark Springs can provide
a sustained supply of about 4 . 3 mgd for a total output of 9. 5
mgd . The combined transmission capacity of the Kent Springs
main and the Clark Springs main is estimated at best at 8. 0
mgd , about 2 . 5 of which is transmitted by the Kent Springs main
and about 5. 5 mgd by the Clark Springs main. Through an intertie
between the two mains the surplus output of the Kent Springs
source is diverted to the Clark Springs main. Although the
source capacity is rated at 9. 5 mgd the transmission capacity
is rated at no more than 8. 0 mgd and possibly slightly less.
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Present and Projected Population
The population of the service area, including Water
Districts 111 and 87 is represented by the following table.
Year Estimated Population
1979 35,000
1980 37 ,600
1981 40,200
1982 42,800
1983 45,400
1984 47 ,900
1985 50,500
1986 53,000
1987 55,400
1988 58 ,000
1989 60,600
1990 62,800
'1 1995 75,000
1 2000 90 ,000
j Present Water Use and Projected Demand
The present and projected water consumption within the
-1 total service area is shown in the following table.
JWATER CONSUMPTION WITHIN KENT'S SERVICE AREA
J YEAR
CATEGORY 1979 1980 1985 1990 2000
Peak Monthly Usage mg 240 264 352 420 600
Peak Monthly Usage mgd 8.0 8 . 8 11 . 8 14 .0 20. 0
Peak 7-Day Usage mgd 10 .4 11 .4 15.3 18 .2 26 .0
�1 Peak 3-Day Usage mgd 11 .2 12.3 16 .5 19 .6 28.0
.J Peak 1-Day Usage mgd 12. 0 13.2 17 .7 21 . 0 30.0
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Total No. of Services 6 ,560 7 ,220 9 ,640 11 ,480 16 ,400
; ) Single Family Services 5,380 5,920 7 , 910 9 ,420 13,450
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Supply and Demand Relationship - Water Shortage
Based on the consumption figures contained in the previous —
table and supply figures provided earlier it may be stated that -.
a shortage presently exists. If no new sources are developed
the shortage will continue to increase. Knowledge of future
demands will enable the City to plan for and develop additional
sources. The following table summarizes the present and
projected shortage.
SUMMARY OF POTENTIAL WATER SHORTAGE FOR 1980
(If No New Sources Are Added)
CATEGORY Supply Demand Shortage Total Shortfall
in mgd in mgd in mgd in mg
Peak 7-Day Usage 8. 0 10_9 2. 9 20.3
Peak 3-Day Usage 8. 0 11 . 8 3.8 11 .4
Peak 1-Day Usage 8.0 12. 6 4.4 4 .4
Hydraulic Analysis and Fire Demands
Generally the distribution system within the service area
is in excellent condition and has the capacity to provide fire
protection in accordance with the specified requirement. An
exception to the above is the higher elevations of the West
Hill especially the north end. The prescribed fire demands are
not presently met, but with the construction of the proposed
1 MG tank on 38th Ave. S.E. and Military Road together with
some mains the fire demands can be substantially met.
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Sources of Additional Supply
There are several sources of additional supply available
to the City. These sources may be classified under two categories:
long term sources which can meet the City ' s needs up to the
year 2000 and even beyond; and short-term sources which can
meet the City's needs over the next three years or so, by which
time the increased demand as a result of growth would have
outstripped those short-term supply sources.
There are two long-term sources. These are the City of
Seattle feeding the valley and the West Hill systems and the
development of the City's own sources at Kent Springs and
Armstrong Springs and transmitting the water to the City
through the East Hill system.
The short-term sources consist of an intertie with the City
of Tukwila which will be completed and in place by the end of
October 1979 , the development of the East Hill Well and the City
of Renton. The first source can supply 2 mgd or possibly more
while the second could supply 2.3 mgd. The East Hill Well is
also under construction and may be completed in the fall of
1979 .
Cost Comparison of New Sources
The following table shows a cost comparision of the sources
of additional supply.
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Capital Improvement Program
The basic needs of the City to meet the present and future
demands consist of source development, transmission and storage.
Post-storage transmission mains whose total cost is estimated at
$2 ,420 ,000 will also be needed as the service area grows and new
areas are developed, but these mains are excluded from the
capital improvement program since they are demand oriented and
it is difficult to predict which specific areas within the
service area will grow first and to what extent. The following
table summarizes the source, transmission and storage needs.
The Capital Improvement Program of the Water System has been
designed to reflect the current conditions and meet the City' s
f� future needs.
The planning for the provision of water facilities has been
-� organized into four phases. These are:
11 . The Immediate Phase: Where improvements are to be
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completed by May of 1980 , with the exception of the
Seattle Intertie to be completed by the Spring of
I 1981 .
�J 2. Short Term Phase: Where improvements are to be com-
pleted during the period of 1980-1984 and no later than
1984 .
J3 . Intermediate Phase: Where projects are to be completed
no later than 1990 .
J4 . Long Term Phase: Where improvements are to be completed
prior to the year 2000 and preferably no later than
1998 .
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Immediate Phase: To be completed by April 1980 .
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
East Hill Well 240,000 Spring ' 80 May ' 80
Tukwila Intertie 60,000 Spring ' 79 October ' 79
Well Testing at 65,000 Fall 179 Spring ' 80
Kent Springs
Construct Intertie 650,000 Summer ' 80 April ' 81
w/Seattle
Construct West Hill 450,000 Fall ' 79 June ' 80
1 MG Tank
Kent Springs Pre- 27 ,000
Design Report
Financial Report & 24 ,000 Spring ' 80 ---
Rate Study
Renton Intertie P.S. 40,000
Seattle-Kent Intertie Fall ' 79 ---
Pre-design report 34,000 Winter ' 79 ---
TOTAL COST $1 ,590 ,000
Short-Term Phase: ( 1980-1984 ) To be completed during the period
1981-1984.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Kent Springs Main 3,200,000 Oct. ' 79-Apr. ' 80 ' 81 , - 82, ' 83
2 Wells at Kent 125, 000 1981 1982
Springs
East Hill 3 MG 850,000 1982 1983
Tank
East Hill 1 MG 475,000 1983 1984
Tank
Develop Armstrong 200,000 1983 1984
Springs
East Hill Pump 300 , 000 1982 1983
Station
TOTAL COST $5 , 150, 000
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Intermediate Phase: ( 1985-1990) Projects to be completed by 1990.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Seattle-Kent 2nd 250,000 1989 1990
Intertie at 224th
& 76th Avenue
Long-Term Phase: ( 1990-2000) Projects to be completed prior to
the year 2000.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Kent Intertie w/ 250,000 1995 1996
Seattle-Tacoma
line of 132nd
Ave. S.E.
Total All 7, 192,000
Phases
.� Post-Storage
Transmission 2 ,420,000
Mains
$9 ,660,000
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RECOMMENDATIONS
On the basis of information developed in this plan the
following recommendations are hereby presented for the Council ' s
action:
1. Adopt this plan as the City' s Water System Plan after
the approvals of King County and the Department of
Social and Health Services are secured.
2. Authorize a rate study to determine the financial
needs of the City based on the facilities the City
needs and which are outlined in the Capital Improvement
Program.
3 . Proceed with the implementation of the immediate phase
and portions of the short-term phase of the Capital
Improvement Program to the extent the financial
resources of the City permit in accordance with the
following schedule of priority.
a. Construct the intertie with the City of Tukwila.
b. Develop and put into production the East Hill Well.
C. Construct the West Hill 1 mg tank on 38th Ave. S.E.
and Military Road.
d. Start the pre-design and design of the Pump
Station for the Renton Intertie.
e. Start the pre-design to be followed by the design
of the Seattle Kent Intertie for project completion
by Spring of 1981 .
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f. Test the Kent Springs site for two-1800 gpm wells.
g. Start the design of the Kent Springs main.
h. Start a phased program for the construction of the
Kent Springs main.
i. Develop two-1800 gpm wells at Kent Springs in
accordance with item a above.
j . Develop one-1400 gpm well at Armstrong Springs
together with a pump station and a force main to
discharge into the Kent Springs main.
k. Construct storage and pumping facilities on the
East Hill consisting of a 3-mg tank, a 1-mg tank
and a pump station to accommodate the total flow
from Kent Springs. The above facilities, when
y� constructed will meet the City' s water needs up
to the year 1990.
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II . INTRODUCTION
This report constitutes a Water System Plan for the City of
Kent, Washington, developed pursuant to the guidelines and
standards promulgated by the Washington State Department of
Social & Health Services (DSHS) . A Comprehensive Water Report
was developed for the City in 1972. In some respects this plan
is an update of the 1972 report. Since then however, the DSHS
has substantially revised the 1972 guidelines & standards result-
ing in what is presently know as a Water System Plan. The
location of the planning area within the region is shown in the
vicinity map of Figure 1 .
AUTHORIZATION
In compliance with the State of Washington Department of
Social & Health Services ' requirement for a Water System Plan
update at five-year intervals, and recognizing the need for
current information based on current trends in growth, the City
of Kent in a letter dated September 6 , 1978 authorized URS
Company to proceed with the preparation of this Water System
Plan.
PURPOSE AND SCOPE
The purpose of this report is to provide the City of Kent
with an up-to-date Water System Plan in accordance with require-
` I ments established by the Washington State Department of Social &
Health Services.
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Lake
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Bainbri
Jefferson County Isla
Mazon County %rx/ ��/ 4 m -
Bremerton
Lake
Sammamish -
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Island
Kitsap County - Planning 01
z f Pierce County Area
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st Pierce County ~\�
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0 2 4 10
Figure 1
Vicinity Map
The updating of the 1972 Comprehensive Water Report will be
based on a number of factors including the latest population
estimates for the service area; the distribution of the population
within the service area; the industrial and commercial demands
for water, population growth within the service areas of other
districts to which the City supplies water; any revisions in
service area agreements and the requirements of the DSHS.
The service area covered by this plan is the City of Kent' s
franchized area as approved by King County. Since the City also
supplies water to King Co. Water District #111 and Water District
#87 , these Districts will be included within the scope of this
plan as far as supply is concerned, although Water District #111
has a water system plan of its own which was updated in late
p� 1978. The boundaries of the service area are shown in Figure 2.
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S 176th St SE 176th St
S 1 Both St
ORILLIA
S 188th St
Angie
Lake , T
_ SE 192nd St
j Panther Lake
LU
2 —
!n
C S 208th St
ci S 212nd St
LU
eel i
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Qf
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> e�
Kent-Des Jai\
5
o.
S 240th St
N
KENT w
d w Meeker
o-
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SE 256th St
Lake w�ej'�'ka
Fenwick Q ley R >
> Q
y UJ N
S 272nd St _o ;)
St r S 277th St SE 272nd St L
Sta Lake R i
Planning Area Boundary
288th St S
f��
North
0 % 1�2 % 1
Figure 2
Service Area Boundaries
III. PLANNING AREA DESCRIPTION
GENERAL
This chapter provides the basic planning data pertinent to
the water system plan. It will provide a description of the
water system' s service area; the present and projected land use
patterns based on adopted plans; the present projected popula-
tion of the service area and the present water uses and projected
demands.
SERVICE AREA BOUNDARIES:
The boundaries of the service area are shown in Figure 2.
The service area is a franchise right granted to the City of Kent
by King County. By Ordinance No. 1315 King Co. on October 23rd
1973 granted the City of Kent franchise rights for watermain
installation, maintenance and operation. Since October 1973
there have been no changes regarding the boundaries of the service
area and no changes are planned in the foreseeable future.
To the East the service area is bounded by Water District
#111 and Water District #58, to the North by the City of Renton
and the City of Tukwila, to the West by Water District #75 , and
to the South by the City of Auburn and Water District #87.
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HISTORY OF THE WATER SYSTEM:
In 1955 the City of Kent adopted it ' s first Comprehensive
Water Plan. Since then the system has undergone numerous improve-
ments and additions which are summerized in the following synopsis:
YEAR ITEM
1955 A comprehensive Plan for water supply and distribution
was adopted by the City of Kent.
1957 The Clark Springs water source was developed together
with a transmission main from Clark Springs to Kent
Springs and improvements consisting of a booster pump
station were installed on the existing transmission
main.
1958 East Hill Water System Improvements were made consisting
of a booster pump station, transmission line and
125,000 gallon elevated storage tank near the intersection
of South 240th Street and 98th Avenue South.
1959 Two pumping stations, two storage reservoirs and
transmission mains were completed.
1964 The Clark Springs Water Supply Main from Kent Springs
:.1 to Kent was completed . This provides the City of Kent
with a second independent transmission main for supply
of water.
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YEAR ITEM
1965 The construction of North Industrial Water Mains
serving areas adjacent to the West Valley Highway,
South 212th Street and South 228th Street was completed.
1966 Federal funds from the Department of Economic Development
Administration were obtained to pay a portion of the
costs of additional water mains to serve the North Kent
area, two (2 ) six million gallon water storage reservoirs
together with required transmission facilities, construc-
tion of walls and pumping stations to increase the
capacity of Clark Springs and a roof over the existing
three million gallon ground reservoir on Guiberson
Street.
1967 Construction was started on the 6 MG reservoir at 240th
and 98th Avenue South.
1968 Construction of the six million gallon reservoir at
240th and 98th Avenue South was completed.
1969 The S. 218th Street Supply Main was completed from the
6 MG reservoir at S. 240th St. and 98th Avenue South
to the North Industrial Area.
The construction of Phase 2 of the North Industrial
Water Mains and the S . 180th St. mains were completed.
The roof over the 3 MG reservoir was completed.
18
YEAR ITEM
1970 The 6 MG concrete reservoir on S . 218th Street and
adjacent supply lines were planned and placed under
construction.
1971 Construction was completed on the S. 218th Street
reservoir and adjacent supply lines.
1972 The 1972 Comprehensive Water Report was completed.
1976 The East Hill Pump Station No. 5 was completed. This
pump station pumps water from the 6 mg. reservoir on
98th & 240th to the 485 ' elevation and 590 ' elevation
�J systems.
1978 The 116th Avenue main extending from Kent Kangley Road
to the North to South 272nd Street to the South was
compl
eted.
1978 Two wells each with a capacity of 2 . 5 mgd were developed
at Kent Springs and brought on line.
1978 A 3 .5 mg joint use reservoir with Water District #111
was completed. The reservoir is at the 590 ' elevation
system and is located near 124th Avenue S.E. and S. E.
288th Street
19
iJ
YEAR ITEM
1979 Construction began on the Chlorination Facilities at
Kent Springs. These facilities will have a capacity of
10 mgd . Completion is expected in the Summer of
1979 .
1979 Work began on upgrading the Water System' s telemetry
and Control System. Completion is expected in the
Summer of 1979 .
1979 Work has been completed on increasing the pumping capacities
of the West Hill Pump Stations #3 and 4 .
1979 The City Council gave the authorization to complete the
design of a one million gallon standpipe at 38th Avenue
S.E. and Military Road to serve the upper West Hill.
AVAILABLE WATER RESOURCES:
Presently the City of Kent depends on two water sources for
supplying its needs. These are the Kent Springs and the Clark
Springs which are located about ten and fourteen miles east of
Kent respectively. The Kent Springs source consists of an
infiltration gallery which is about fifty years old and two new
wells completed in 1978 . The capacity of the infiltration
gallery varies considerably but for most of the year it matches
the transmission line capacity of about 3 mgd. The combined
capacity of the two wells is about 5 mgd.
20
The Clark Springs source consists of an infiltration gallery
which was developed in 1957 and three wells whose practical
capacity is about 5 mgd. The infiltration gallery and the wells
are used alternatively.
The City of Kent presently has no other active sources of
supply. Interties with Water District #75 and Renton allow the
City to purchase water when and if necessary but these sources
are not used as a normal source of supply. A source which is
presently being investigated is a well owned by the East Hill
Community Well Company. This source could have the potential of
3 mgd when developed. This figure however is only an estimate
which can only be ascertained by well development. Presently
under construction is an intertie with the City of Tukwila which
:.� will be completed in October of 1979 .
CHARACTERISTICS OF THE SERVICE AREA
The Service Area encompasses the incorporated City of Kent
plus some additional unincorporated areas within the jurisdiction
of King County. Figure 1 shows the location of the Service Area;
Figure 2 shows its boundaries. The area covers approximately
27 square miles. Land use in the Service Area includes a mix
of residential, commercial , and industrial uses. The area' s
proximity to the employment centers throughout the Seattle-Tacoma
P area makes it well suited to commuter-oriented residential
Jdevelopment. Industrial growth is expanding along the Kent
Valley floor transforming the use from agriculture to industrial
use. Kent is close to Seattle and Tacoma, Sea-Tac International
�� 21
Airport, two major transcontinental rail lines, two major inter-
state freeways, and substantial amounts of flat industrially
zoned land which contributes to attracting new industry to the
Kent area. The area is expected to continue to experience
economic and population growth for the next several years.
At present about 20 square miles within the planning area
are served by the City of Kent.
The principal topographic features are the upland plateaus
rising from both sides of the Green River Valley. The valley
itself connects the adjoining cities of Auburn to the south and
Tukwila and Renton to the north. The valley is about 2-1/2 miles
wide with an elevation ranging from 30 to 40 feet above sea level
before it ascends to two bordering hills. The West Hill rises
quickly to about 400 feet with a steep slope while the East Hill
rises to about 400 feet with a more gentle slope. Because of the
East Hill ' s gentle slope, more development has occurred there.
The topography of the service area is shown in Figure 3.
The geology of the Puget Sound area is primarily the result
of processes which occurred during the Vashon period of the great
Frasier glaciation about 15,000 years ago. The major portion of
the region was covered by ice several hundred feet thick. As the
ice moved, it compressed the underlying earth and carved it into
the valleys and ridges present today. In addition, the glacier
scraped away the pre-existing soil of the area. As the ice
retreated, it left behind the geologic and soil types characteristic
of glaciated areas. The geology of the Service Area is predominantly
very dense and consolidated material called glacial till over
22
i ,. r a •(4(� 1 4
y 1
J.
v.
'�- ;x. .� �:.., °! - I ; � i,�•$ o+t is �r ri;.��t4�,- '{ '
I" w
p t
t.ac 2
u N },k 1
-:;--
Y ----------
a ,.
Kent YI
,
jt
g,
LI
1 a l Planning AnIa-Bovad
-j..
r
Miles
North
F14/2 I
Figure 3
Service Area Topography
•
varying thicknesses of clay, sand, or bedrock. The till is
overlain by erosional material.
The Service Area is influenced by the West Coast Marine
climate which is characterized by mild, wet winters and cool,
relatively dry summers. Most precipitation occurs as rainfall,
although snow does occur almost every year. Approximately 75% of
the rainfall occurs between October 1 and April 1 , with a mean
annual precipitation of 34 . 1 inches in Kent.
Temperatures are moderated by the proximity of Puget Sound.
The mean annual temperature in Kent is 51 . 7 degrees F. while the
maximum and minimum recorded readings are 100 degrees and -5
degrees respectively.
The prevailing winds in the region are from the south in the
fall and winter, gradually shifting to the north in late spring
and summer.
INVENTORY OF RELATED PLANS
There are other plans which may be related to this Water
System Plan. Some of these plans have been developed by the City
of Kent while other plans fall within other jurisdictions. The
City of Kent has developed the City' s Comprehensive Plan which
contains the elements of Natural Environment , Circulation,
Housing , Human Resources, Economic, Public Utilities & Human
Environment. The City also developed the Wastewater Facility
Plan which serves approximately the same area but slightly
larger.
2 4-
Other plans which may be pertinent are the water system
plans of adjacent purveyors which include Renton, Tukwila, Water
District #58 , Water District #111 , Auburn and Water District
#75.
LAND USE AND ZONING
Historically, the Green River Valley has been used for
agricultural purposes because of its excellent soil . However,
because of its location near Seattle-Tacoma, the Sea-Tac Airport,
and two railway lines, recent decisions to locate new freeways to
improve accessibility, new utilities, and flood control devices
constructed in the Valley, it has been transformed into an
industrial area with residential areas lining the hillsides.
Increasing property taxes forced many farmers to sell their lands
to speculators when farming was no longer profitable. Much of
the undeveloped land is owned by speculators who lease land to
lfarmers until the land is ready to be developed to a more intensive
J
land use. Much of the valley floor is zoned for industrial use
now. The trend for the valley has been to become more urbanized
�1 and industrialized, while the hillsides on either side of the
valley have been developing into more single family and multi-
family housing along with neighborhood commercial facilities.
The commercialization and industrialization of the valley has
been at the expense of a reduction in the agricultural lands.
w] On the other hand the extensive housing developments on the
hillside have been at the expense of a reduction in open space.
These trends are likely to continue in the future.
25
i
The zoning within the service area follows the trends
outlined above. Much of the valley is zoned industrial and
commercial interspersed with other uses while the hillsides and
the higher elevations are zoned primarily single family and
multi-family residential and neighborhood commerical.
A portion of the service area falls within the Soos Creek
Plateau Land Use Plan. This plan covers the East Hill of Kent
and substantial areas lying easterly. The zoning for those areas
of the service area which fall within the Soos Creek Plan is
similar to that called for by the City ' s Comprehensive Plan which
is single and multi-family residential and neighborhood commercial.
POPULATION ESTIMATES AND PROJECTIONS
The population of the service area can only be estimated
since the boundaries of the service area do not coincide with any
political jurisdiction for which data is readily available. The
service area falls primarily within the City of Kent but a
substantial portion of it falls within the unincorporated areas of
King County.
In developing population estimates and projections use was
made of the Puget Sound ' s Council of Governments Activity Alloca-
tion Model. Ths model has been used by PSCOG for the past
several years to estimate the population of multi-jurisdictional
areas in Puget Sound. It is not the intent of this section to
examine the mechanics of the model but rather to point out the
the fact that it is the basis upon which the population estimates
and projections have been made.
26
The model subdivides areas within Puget Sound into districts
which are numbered. Those districts comprising the service area
have been identified. Each district contains varying percentages
of the service area within it. This percentage has been applied
to the service area and the total has been arrived at by adding
the figures for all the districts. Based on the above Table 1
has been constructed. Table 1 shows that the population of the
service area in 1976 was 25 ,000 , in 1980 it will be 31 ,000 and in
1990 it will be 49 ,000 . These figures if plotted fall in a
straight line whose slope amounts to 5% annual growth.
By contrast the population within the City of Kent has
changed from 16,928 in 1975 to 19,400 in 1978 or approximately
4 .9% for the last three years. The detailed calculations show
that this trend will continue until 1990 .
As a means of checking the validity of the projections
contained in Table 1 , the Planning Department of the City of Kent
reviewed the projections and changes were made based on specific
information related to the future growth of each of the AAM
Districts. As projections extend farther into the future the
degree of certainty diminishes, but if recent growth trends which
ihave been evident over the last few years continue the projections
1 should be considered reasonable and realistic.
27
TABLE 1
POPULATION ESTIMATES AND PROJECTIONS
FOR KENT'S SERVICE AREA
Activity -
Allocation
Model Service Area Population -
District
Number 1976 1980 1985 1990 2000
3050 3 , 547 4 ,300 5,700 7,200 10,300
3150 1 ,556 1 ,800 2,400 3, 000 4,250
3400 4 ,057 5, 100 7,000 8 ,400 12,000
3410 2 ,874 4,000 5,400 6 ,650 9,500
3440 2,064 2,400 3,250 4,000 5, 750
3450 6,240 9 , 100 12,400 15,400 22, 100 -
3460 224 300 400 500 800
3510 3, 148 4 ,000 5,300 6,650 9 ,500
3540 1 , 144 1 ,300 1 , 750 2, 100 3,000
W.D. 111 4 ,400 5,300 7,200 8 ,900 12,800
Total
Service 29 ,300 37 ,600 50,500 62,800 90 ,000
Area
TABLE 2
SERVICE AREA
POPULATION PROJECTIONS BY YEAR
YEAR POPULATION
1976 29 ,300
1979 35,200
1980 37 ,600
1981 40,200
1982 42,800
1983 45,400
1984 47, 900
1985 50,500
1986 53 ,600
1987 55,400
1988 58 ,000
1989 60,600
1990 62,800
1995 75, 000
2000 90 ,000
28
PRESENT WATER USES AND PROJECTED DEMAND
For the purposes of this report actual consumption figures
will be used and then related to the total population served. In
order to project future demand the future population figures have
been used together with per capita consumption figures presently
found in the service area. One underlying assumption which
should be pointed out is that the present ratio of industrial and
commercial water usage to the total consumption will hold true
for the planning period. This means that whatever new industries
are established in the service area the overall population will
rise to keep pace with it and thereby maintain roughly the same
proportion.
The consumption figures used herein are those of July
of 1979. Water usage over periods longer than one month have no
practical significance in terms of the ability of the City to
supply the water needed within its service area. Usage figures
over shorter periods of time are the most relevant and the most
critical for planning purposes. The following Tables have been
constructed based on information given by the City of Kent Water
Department. The tables are followed by a graph which shows
demand-supply relationship and the need for additional sources of
Jsupply.
29
TABLE 3
WATER USE WITHIN KENT'S SERVICE AREA
1979 1980 1985 1990 2000
Peak Monthly Usage mg 240 264 336 420 600
Peak Monthly Usage mgd 8.0 8.8 11 .2 14 .0 20. 0
Peak 7-Day Usage mgd 10.4 11 .4 14 .6 18.2 26 .0
Peak 3-day Usage mgd 11 .2 12. 3 15. 7 19. 6 28.0
Peak 1-day Usage mgd 12.0 13.2 16 . 8 21 . 0 30.0
Total No. of Services 6,560 6,890 9 , 180 11 ,480 16 ,400
Single Family Services 5,380 5,650 7,530 9 ,420 13,450
TABLE 4
WATER USE
FOR JULY 1979
BY SUB-AREAS
Daily
Usage Peak Peak Peak
Usage Mg. Peak 7-Day 3-Day 1-Day
Peak Month Usage Usage Usage
Sub Area Monthly GPM GPM GPM GPM
485 ' System 21 .6 500 650 700 750
590 ' System 40.8 940 1 ,230 1 ,320 1 ,410
WD111 System 31 .2 720 940 1 ,010 1 ,080
Valley System 122.4 2,830 3,670 3, 960 4,240
West Hill System 24. 0 560 730 780 850
Total in GPM 240 mg. 5,550 7,220 7, 770 8 ,330
Total in mgd 8. 0 8.0 10 .4 11 .2 12.0
30
TABLE 5
PROJECTION OF
WATER USE
FOR JULY 1980
BY SUB-AREAS
Daily
Usage Peak Peak Peak
Usage Mg. Peak 7-Day 3-Day 1-Day
Peak Month Usage Usage Usage
Sub Area Monthly GPM GPM GPM GPM
485 ' System 23.8 550 700 700 830
590 ' System 44.9 1 ,030 1 ,340 1 ,440 1 ,540
WD111 System 34.3 790 1 ,030 1 , 110 1 , 180
Valley System 134.6 3, 110 4,040 4 ,350 4,670
West Hill System 26.4 620 800 870 930
Total in GPM 264 mg. 6 , 100 7,430 8 ,540 9 , 150
Total in mgd 8 .8 8.8 11 .4 12.3 13.2
� 1
TABLE 6
PROJECTION OF WATER
USE FOR JULY 1985
BY SUB-AREAS
Daily
Peak Usage Peak Peak Peak
Monthly Peak 7-Day 3-Day 1-Day
Usage Month Usage Usage Usage
Sub Area Mg- GPM GPM GPM GPM
485 ' System 31 .7 740 960 1 ,040 1 , 110
590 ' System 59 .8 1 ,390 1 , 810 1 ,95U 2,090
WD111 System 45.8 1 , 060 1 ,380 1 ,480 1 , 590
Valley System 179.5 4 , 150 5,400 5,810 6,220
West Hill System 35.2 820 1 , 060 1 , 150 1 ,230
Total in GPM 352 8 , 160 10 ,610 11 ,4
30 12,240
It Total in mgd 11 .2 11 .2 14 .6 15. 7 16 .8
1�
I�
31
c�
TABLE 7
PROJECTION OF WATER USE
FOR JULY 1990 BY SUB-AREAS
Daily
Peak Usage Peak Peak Peak =
Monthly Peak 7-Day 3-Day 1-Day
Usage Month Usage Usage Usage
Sub Area Mee . GPM GPM GPM GPM
485 ' System 30.2 880 1 , 140 1 ,230 1 ,320
590 ' System 71 .4 1 ,650 2, 150 2,310 2,480
WD111 System 54.6 1 ,260 1 ,640 1 ,760 1 ,890
Valley System 214 .2 4,960 6 ,450 6,950 7,440
West Hill System 42.0 970 1 ,260 1 ,360 1 ,450
Total in gpm 420 9 ,720 12,640 13,610 14 , 580
Total in mgd 140 14 . 0 18.2 19.6 21 . 0
TABLE 8
PROJECTION OF WATER USE
FOR JULY 2000
BY SUB-AREAS
Daily
Peak Usage Peak Peak Peak
Monthly Peak 7-Day 3-Day 1-Day
Usage Month Usage Usage Usage
Sub Area MI_ GPM GPM GPM GPM
485 ' System 54.0 1 ,250 1 ,630 1 , 750 1 ,880
590 ' System 102.0 2,370 3,080 3,320 3, 550
WD111 System 78.0 1 , 800 2,340 2, 520 2,700
Valley System 306. 0 7,080 9 ,200 9 ,910 10,620
West Hill System 60.0 1 ,390 1 ,810 1 ,950 2,090
Total in gpm 600 13,890 1 ,8060 19,450 20,840
Total in mgd 20.0 20. 0 26. 0 28 . 0 30.0
32
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IV. DESCRIPTION OF THE EXISTING SYSTEM
GENERAL
The City of Kent ' s franchised area consists of 27 square
miles of territory which includes the City of Kent and its
outlying areas. Moreover the City supplies water to King Co.
Water Districts #87 and 111 . The City' s distribution system
consists of over 80 miles of mains, 8 reservoirs with a total
capacity of approximately 19 mg, 3 pump stations and five pressure
zones/elevations, comprising 5 sub-areas. The sources of supply
for the City are Clark Springs Source and the Kent Springs source.
This chapter will address the source and transmission aspect
i as well as the distribution and storage aspect within each of the
_1 five pressure zones comprising the total system within the
franchised area.
SOURCE AND TRANSMISSION:
Water for the City of Kent ' s system is received from two
Jsources: the Clark Springs source which has a maximum practical
capacity of 3 ,500 gpm or 5 mgd and the Kent Spring source which
has a capacity of 3 ,600 gpm or 5 .2 mgd under pumped conditions.
Although these two sources are approximately equal in
capacity the transmission capacity serving each source does not
match its own source. The Clark Springs transmission main which
Jstarts at the Clark Springs Source and terminates at the 6
million gallon reservoir on 98th Avenue South and South 240th
34
�J
Street has a gravity flow capacity of 5 . 0 mgd with the reservoir
full and 5 . 8 mgd with the reservoir empty. Under forced flow
condition the main has a capacity of 7 . 5 mgd with a head of 110
feet . Experience has shown, however, that the Clark Springs
source cannot sustain a pumped flow of 7 .5 mgd for more than one
day. During the summer months when the water table is normally
at a lower elevation the average production from this source has
been around 3 ,500 gpm or 5. 0 mgd and during the summer of 1978 it
dropped to 2,400 gpm or 3 . 5 mgd for a short time. It may be
assumed that the average gravity flow capacity is about 5. 4 mgd
or 3 ,800 gpm.
The Kent Springs transmission main has a theoretical gravity
flow capacity of 3 .2 mgd but a practical capacity of about 2.0 -
2. 5 mgd due to the deteriorating condition of the main. The
excess production capacity of Kent Springs which cannot be
transmitted by the Kent Springs main when the two wells are being
pumped is diverted to Clark Springs main through an intertie.
This condition will materialize, however, when the production out
of Clark Springs is below 3 , 800 gpm thus creating an excess
transmission capacity which may be utilized by diverting water to
the Clark Springs main from the Kent Springs source.
Although the production capacity from both sources may
exceed 10 mgd the total transmission capacity of both mains
therefore ranges from a low of 7 . 5 mgd to a high of 8 .0 mgd or
5200 gpm to 5550 gpm.
35
PRESSURE ZONES
The total service area is divided into five sub areas each
of which has a distinct hydraulic level . These pressure zones
are: The East Hill and Water District #111 at elevation 590 feet
above sea level, the East Hill intermediate level at elevation
485 feet, the Valley level at elevation 240 feet, the West Hill
intermediate level at 354 .5 feet, and the high West Hill system
at elevation 529 feet.
The following is a description of the East Hill System
which has a two pressure zones at 590 ' and 485 ' , the Valley
System which has one pressure zone at 240 ' and the West Hill
System which has two pressure zones at 354 .5 ' and 5291 .
THE EAST HILL SYSTEM:
This system is served by a one-million gallon tank located in the
vicinity of 112th Avenue S.E. and North of S.E. 236th Street and
a 3 . 5 million gallon tank located east of 124th Avenue S.E. and
S.E. 286th Street. Both tanks are elevated steel tanks with the
high water surface at elevation 590 ' . A third six-million gallon
Jtank is located west of 98th Avenue South and North of S. 240th
Street. This tank serves as a holding reservoir into which the
-� Clark Springs main discharges. The high water surface elevation
of this tank is at 416 feet. Water from this 6 million gallon
tank is pumped by Pump Station #5 into the one-million and
3 . 5 million gallon tanks at elevation 590 serving the high East
Hill System and into the 125 ,000 gallon tank at elevation 485 '
J
36
�J
serving the low East Hill System. Water also gravitates to the
6 million gallon tank located on South 218th Street and 98th
Avenue South. This tank is at elevation 240 feet and supplies
the low Valley System.
In terms of storage the East Hill System contains four
tanks. Two of the tanks have a combined capacity of 4. 5 mg and
they serve the higher system at elevation 590 . One tank has a
capacity of 125 ,000 gallons and it serves the low East Hill
System at elevation 485 ' . The 6-million gallon tank acts as a
receiving reservoir into which the Clark Springs main discharges
and from which water is pumped to the two levels of the East Hill
System. Since the elevation of this tank is at 416 ' water
gravitates to the 6-million gallon tank on South 218th Street and
98th Avenue South. This tank is at elevation 240 and it serves
the low Valley System.
The East Hill System serves Water District #111 where a
number of interties exist between the District and the City of
Kent ' s system. The 3 .5 million gallon tank was built in 1978 as
a joint use reservoir and jointly paid for by the City and the
District. Hydraulically the two systems act as one system having
the same hydraulic elevation. Water District #111 , however
maintains a 150 ,000 gallon tank of its own. The District ' s
system is connected with the City of Kent ' s system by three
interties all of which are located in the vicinity of 124th Ave.
S.E . One intertie is along S.E . 256th Street, one along S.E.
277th Street and the third is located near S.E. 282nd Street.
37
All of the interties are metered and the District purchases all
of its water from Kent.
Excluding the two transmission mains which originate at Kent
Springs and Clark Springs the higher East Hill system contains
1 ,200 feet of 16" main, five miles of 12" , 2.6 miles of 10" , 6 .6
miles of 8" and several more miles of 6" mains. The boundaries
of this system whose hydraulic elevation is 590 ' are 124th Avenue
S.E. to the East, S.E. 277th Place to the South, 98th Avenue S.E.
to the West and S.E. 224th Street to the North.
The lower East Hill System at elevation 485 feet serves the
westerly slopes of the East Hill. It' s boundaries are approximately
98th Avenue South to the East, S. 257th Street to the South,
Clearview Avenue South to the West, and the North extremity of
Hilltop St. to the North. Most of the system consists of 6" mains
-� with about 800 feet of 10" and 2 ,200 feet of .8" .
`l Pump Station #5 which is located at the site of the 6
million gallon 416 ' elevation tank (James Street Tank) serves
both pressue zones of the East Hill System. The pump house
presently contains 3 pumps and room is provided for two more
pumps should the need arise to install them.
J
One of the pumps serves the 125 , 00 gallon tank at elevation
485 feet. At 1 ,750 RPM the pump can deliver 1 , 750 gpm. Another
pump serves the two tanks at elevation 590 . At 1 ,750 RPM it can
deliver 1 ,750 gpm. The third pump serves both pressure zones.
At 1 , 100 RPM it can deliver 1 ,750 gpm to the 485 ' system and at
38
1 , 750 RPM it can deliver 1 ,750 gpm to the 590 ' system. The
present capacity of any two-pump combinations adds up to 3 ,500
gpm to either pressure zone but not to both of them simul-
taneously. By adding two more pumps in the future the pumping
capacity may be boosted to 7 ,000 gpm. At the present time there
are no plans to increase the capacity of Pump Station #5.
THE VALLEY SYSTEM
This system has a hydraulic elevation of 240 feet and is
served by two tanks. The 6-million gallon tank at South 218th
Street and 98th Avenue South serves the northerly portions of the
Valley System while the 3-million gallon tank also known as the
Scenic Hill reservoir serves the southerly portions of the Valley
system.
The 218th Street reservoir receives its water by gravity
from the 416-foot elevation 6-million gallon reservoir on the
East Hill , which in turn gets its water from Clark Springs via
the Clark Springs main. The Scenic Hill reservoir receives its
water directly from the Kent Springs source via the Kent Springs
main.
In terms of the area served , the total consumption and the
amount of mains serving this system, the Valley System is the
most extensive and the largest of the three systems. Excluding
the 16" main which delivers water from the 416 ' elevation 6-million
gallon tank to the 240 ' elevation 6-million gallon tank, the
system contains about 8 miles of 16" mains, 12 miles of 12"
39
mains, 10 miles of 10 " , 6 . 6 miles of 8" main and several more
miles of 6" mains.
The boundaries of the Valley System extend from South
180th Street to the North, South 277th Street to the South, the
Green River to the West and approximately 98th Avenue South to
the East. Most of the large diameter mains are located in the
north part of the Valley System while most of the 6" and 8" mains
are located in the downtown area of Kent.
THE WEST HILL SYSTEM
Similar to the East Hill System the West Hill System consists
of two pressure zones. The lower is at elevation 354 . 5 feet and
the higher is at elevation 529 feet. The lower level is served
by a one-million gallon tank located in the vicinity of Reith
Road and South 256th Street. The higher elevation is served by
a 300 ,000 gallon tank located in the vicinity of Military Road
and South 256th Street.
The West Hill System is supplied by the Valley System
through a 12" main which crosses the Green River along Meeker
Street and terminates at Pump Station #3 , which pumps the water
into the 354 . 5 ' elevation one-million gallon tank. Pump Station
No. 4, which is located at the one-million gallon tank site pumps
the water into the 529 ' elevation, 300 , 000 gallon tank.
Pump Stations 3 and 4 have been upgraded. Pump Station #3
Jhas two 50-HP pumps. The capacity of one pump is rated at
Jabout 950 gpm. Where the two pumps are operating simultaneously
40
J
the combined capacity is about 1 ,400 gpm. Under normal operating
conditions only one pump is operating.
Pump Station #4 also contains two pumps of similar capacity.
Under normal operating conditions, however, only one pump is
operating.
The West Hill System contains about one mile of 12" main,
1 ,800 feet of 10" , 4 miles of 8" and several miles of 6" and 4"
mains. The area served by the two pressure zones of the West
Hill System is bounded by the Kent Des Moines Road to the North,
by Lake Fenwick Road and Kent Des Moines Road to the East, by
Interstate 5 to the West and by South 272nd Street to the South.
RECENT SYSTEM IMPROVEMENTS
In the past few years the City has undertaken a number of
projects to upgrade the water storage and distribution system.
Among those improvements are the 3 .5 million gallon reservoir
built jointly with K.C.W.D. #111 , the 116th Avenue main which is
over 6 , 000 feet of 12" main; the modifications to the West Hill
Pump Stations; the development of two new wells at Kent Springs
with a combined capacity of about 5 mgd; the installation of a
complete system of telemetric controls and equipment and the
construction of chlorination and metering facilities at Kent
Springs. Recently the City Council authorized the design work
on a new one-million gallon reservoir to serve the higher eleva-
tions of the West Hill.
41
Presently the City chlorinates the water coming from Kent
Springs at a chlorination station located on Kent Kangley Road
and 152nd Avenue South. Water from Clark Springs is chlorinated
at the source before it leaves to the City via the Clark Springs
main. Upon the completion of the chlorination facilities at Kent
Springs the 152nd Avenue station will be removed.
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CHAPTER V
HYDRAULIC ANALYSIS AND FIRE DEMANDS
GENERAL
A hydraulic analysis was conducted on each distinct system
of the distribution network to assess its operating characteris-
tics and identify deficiencies under present and future demands.
Information obtained from this analysis was utilized in formulat-
ing the recommendations to be presented later in this report.
The systems were first studied on the basis of peak demand
for domestic, commercial and industrial consumption to locate the
problem areas in supplying normal peak usage. The magnitude of
the peak demand was based on the standards of the Washington
State Department of Social and Health Services, except in specific
instances where consumption rates have been documented, as in the
Low Level System analysis.
Each system was also examined as to its ability to provide
known fire flow requirements to various school, industrial and
commercial buildings. The fire flow requirements employed
are those established by the Washington Surveying and Rating
Bureau.
In circumstances where further investigation was justified,
additional computer runs were made to evaluate the effectiveness
of conceivable improvements to correct the existing deficiencies.
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43
The results of these computerized simulations are presented
in the following discusssions.
WEST HILL SYSTEM
The West Hill System ranges in ground elevation from 275 to
450 feet above sea level , and its water storage elevation is at
529 feet above sea level . The higher ground elevations are
located in the north end of the system, approximately 7500 feet
from the 300 ,000 gallon elevated storage tank. The small eleva-
tion differential of 80 feet from the water storage elevation and
the losses generated in transmission create difficulties in
maintaining adequate pressure in the north end.
The major fire flow requirements have been established at
the Sunnycrest Elementary School in the north end and Totem
Junior High School in the south part of the system. Both schools
are rated at 2500 gpm fire flow demand, with a minimum pressure
at the fire of 20 psi. A computerized simulation of the West
Hill System indicated marginal fire protection exists at Totem
Junior High where the required 2500 gpm fire flow was delivered
during a peak usage period but at substandard pressure of 17
psi.
A second computer run which simulated a fire at the Sunny-
crest School during peak demand showed the fire protection there
to be more seriously deficient. The system could not deliver the
2500 gpm to the school at any pressure due to large friction
44
losses in the long , smaller diameter pipes leading north to the
school from the storage tank.
Additional computer runs were made to evaluate any potential
benefits to the West Hill System' s operation with the installa-
tion of a 14-inch diameter pipe running along Military Road from
the elevated tank to the top of the hill in the north end. It
was anticipated such an improvement would raise the gradient in
the north end of the system and increase fire flow capabilities
to the Sunnycrest School . Results of these computer runs showed
a 4 psi rise in pressures on top of the hill during peak consump-
tion, but the required fire flow still was not avilable to the
school. More flow capacity would be required between Military
Road and the school to decrease friction losses to a level which
would allow for adequate fire protection during the peak consump-
tion period of the day.
iiAlso investigated through computer network simulation were
j the effects of valving off the area of higher ground elevations
and pressurizing it by use of a booster pump station to maintain
adequate pressures on top of the West Hill. The system model
operated satisfactorily under a peak demand situation, with
i1 pressures throughout the service area in excess of 34 psi.
U However, by valving off a portion of the distribution network,
performance under fire flow conditions was worsened in the
remainder of the system, particularly at the Sunnycrest Elemen-
tary School .
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W
WEST HILL INTERMEDIATE SYSTEM
The West Hill Intermediate System lies in the transitional
zone between the West Hill plateau and the valley floor. The
area served by this system is small , and future growth is severely
limited by the surrounding topography.
The distribution system is very small in relation to the
storage for the system which consists of a one-million gallon
reservoir with a water surface elevation at 354 . 5 feet above sea
level. Large-diameter pipes dominate the system, minimizing
friction losses and making a computerized hydraulic analysis
unnecessary.
As recommended in the 1972 Comprehensive Water Report, the
City has increased the pumping capacity at Pump Stations 3 and 4
which supply water to the Intermediate System and subsequently to
the West Hill System.
LOW LEVEL SYSTEM (VALLEY SYSTEM)
The Low level system is supplied by the 6 MG reservoir at S .
218th St. and the 3 MG reservoir on Guiberson Street both with
water storage elevations of 240 feet above sea level. Ground
surface elevations in the service area range from 20 to 110 feet
above sea level.
Since the Comprehensive Water Report of 1972 , no significant
changes have been made to the Low Level System and peak flow
requirements are still within the range utilized in the 1972
analysis. For this reason, a computer analysis of the total
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existing Valley system was not necessary. From the computer
simulation made in 1972 it can be seen that excellent pressures
prevail throughout the system when operating under the demands of
, peak consumption and fire requirements. Any minor improvements
which have been made have served to strengthen the system.
However, a computer analysis was made on a portion of the
; I Valley System to see if it 'is possible to serve part of the
valley floor and the West Hill with City of Seattle water through
an intertie with the City of Tukwila water system near S. 184th
St. The portion of the valley studied included all of the Low
Level System north of S. 212th St. , all that portion west of W.
lValley Rd. and north of the Kent-Des Moines Highway and including
I the 6 MG S. 218th St. reservoir.
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For the of the hydraulic analysis, this area is
purposes
referred to as the North Valley System. In the computer simulation,
it was assumed that during the peak flow period of the day, flow
through the intertie from Tukwila to the North Valley System
could be maintained at a 2 MGD flow rate, or 1400 gpm but would
not exceed this rate. During this time, the system would draw on
both the intertie and the reservoir, and at night the reservoir
would fill as demand decreases.
The first computer run was made with the system experiencing
J peak demand draws totalling 3300 gpm, 1780 gpm of which represents
the valley usage. Good pressures resulted throughout the system,
..� and 1520 gpm were available to Pump Station No. 3 for the West
Hill systems. The draw from the S. 218th St. 6 MG reservoir was
47
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1900 gpm with the remainder being supplied through the simulated
Tukwila intertie.
A second computer run was made to simulate the North Valley
System during both peak consumption and a 5000 gpm fire at the
industrial area at West Valley Road and S. 212th Street, the
largest fire flow requirement in the system. It was assumed
pumping operations to West Hill would be temporarily suspended to
help the system meet the fire demand. The outcome of this run
indicated unacceptable low pressures would result in such a
situation unless the remainder of the Low Level System were
called upon to augment flow into the North Valley System though a
pressure reducing valve station.
The remaining portion of the Low Level System which lies
outside the North Valley system would be improved by the separation.
By decreasing the service area and removing the larger industrial
users, friction losses would be reduced, thereby strengthening
the distribution system. However, the existing PRV station on
S. 218th St. and 93rd Avenue South would need to be reactivated
on a full time basis to provide a route from the 6 MG reservoir
on S . 240th Street and 98th Avenue South. This would provide
the storage needed to replace the S. 218th Street reservoir which
would be isolated with the area to be served by a possible
intertie with Tukwila.
EAST HILL INTERMEDIATE SYSTEM
The East Hill Intermediate System serves the higher areas in
the City of Kent along the east side of the valley. The supply
48
for the system is a 125 ,000 gallon elevated tank with water
storage elevation of 485 feet above sea level. Ground surface
elevations in the service area of the Intermediate System range
from 95 to 405 feet above sea level, the lower areas being served
through pressure reducing valves.
The network is well gridded, allowing for efficient distribu-
tion of flows with minimal friction losses. Little growth can be
seen for the Intermediate System, as the topography limits the
size of the service area and development is extensive.
EAST HILL SYSTEM (AND WATER DISTRICT NO. 111 )
1 The hydraulic analysis of the East Hill System was done in
conjunction with the Water District No. 111 System due to the
combined nature of the systems. They share use of a 3. 5 million
gallon reservoir at approximately S.E. 288th St. and 124th Ave.
S.E. , and three one-way interties; one each at S.E. 256th St. ,
S.E. 277th St. and S. E. 282nd St. There is additional storage
in the one million gallon standpipe on 112th Ave. S. in the East
t1 Hill System, and the 150,000 gallon elevated tank in Water
District 111 , on 128th Ave. S.E. , north of S . E. 256th St. All
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three storage tanks have a water surface elevation of 590 feet
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above sea level. Ground surface elevations within the service
area range from 365 to 490 feet above sea level.
The first computer simulation was made with the system
, experiencing peak demand and being supplied with no pumps
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operating. The minimum resultant pressure was 43 psi in the area
of 116th Ave. S.E . and S.E. 240th St. This was attributable to
the relatively small 100-foot elevation differential of the
ground in this vicinity, and the 590 ' static gradient of the
system. Friction losses were not a significant factor. it
should be noted that during this peak demand situation, the
largest storage facility, the 3.5 million gallon reservoir, only
contributed 23 percent of the flows to the system. This is
attributable to the lack of highly developed areas in close
proximity to the new reservoir. As the area develops and usage
increases, the distribution network will expand correspondingly
to provide the needed line carrying capacity in the vicinity of
the reservoir.
Another run was made to analyze the system with regard to the
major fire flow requirements of the service area. The largest of
these is the Kent-Meridian High School which is rated at 5000
gpm. Computer simulation showed the system can deliver the
required flow to the high school at a pressure of 27 psi while
simultaneously supplying peak demand flows to the rest of the
service area. One-half of the fire flow originated at the 1 MG
standpipe, while one-third of the fire flow was produced by Pump
Station No. 5 which was assumed to be running in the event of a
fire. The 3 . 5 MG reservoir contributed approximately one-sixth
of the flows to the fire, while the 150 ,000 gallon elevated tank
in Water District No. 111 increased its supply to the District
system to compensate for a decrease in flows normally supplied
through the interties from the East Hill System of Kent.
50
The Park Orchard Elementary School ' s fire flow requirement
of 3000 gpm can be supplied at a pressure of 30 psi during times
of peak demand. The good performance characteristics for the
school are derived from its proximity to the 1 MG standpipe and
the large lines leading to the school.
The Pine Tree Elementary School has a 3500 gpm fire flow
requirement, and it is adjacent to the 3. 5 MG reservoir. A
computer run was made simulating peak demand in the system, and a
fire at Pine Tree Elementary. This run showed the required fire
flow can be supplied at the school with a residual pressure of 29
psi , but pressures in the area adjacent to the school approach the
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minimum acceptable. The 3 . 5 MG reservoir furnishes over half the
fire flow to the school , and supplies a reduced flow through the
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L S.E. 282nd Street intertie to Water District 111 . , There is
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increased flow from the 150 ,000 gallon elevated tank to the Water
District 111 System to compensate for the interruption of flows
Jthrough the S . E. 277th St. and S. E. 256th Street interties.
JThe distribution system was also analyzed with regard to a
residential fire in the eastern end of Water District 111 near
Lake Meridian, a situation which would maximize friction losses
through the smaller pipes in the network. The results of this
computer analysis indicated there is no problem in fire flows
migrating across the system to the east side of the lake. A 1000
i gpm fire flow was delivered at 36 psi, supplied mostly by increased
flows from the 3 . 5 MG and 150 ,000 gallon reservoirs with help
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from Pump Station No. 5. The flow rate from the 1 MG reservoir was
throttled by the flows from Pump Station No. 5 and fed less water _
into the system than it would if no fire were present and the
pump station was off.
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VI. SOURCE ANALYSIS
PRODUCTION AND CONSUMPTION DATA
In Chapter III the present and future consumption figures
were presented. Also presented were the available water resources.
To summarize a reasonably reliable amount of 7.5 mgd can be
delivered by the existing facilities while the consumption using
1979 figures as shown in Table 3 may reach as high as 9.0 mgd
over a seven-day period or 9. 7 mgd for 3-day peak usage period.
Using the 7-day consumption figure the City is left with a
deficit of 1 .6 million gallon per day. Using the 3-day consumption
figure the deficit would amount to 2.3 million gallon per day.
The shortfall over the 7-day period would amount to about 11
million gallons, while the 3-day shortfall would amount to about 7
million gallons. Although the peak one-day usage is 10. 5 mgd
which would result in a deficit of 3 mgd this deficit can be made
up from storage should the consumption return to the average
daily consumption in the peak month which is 7. 0 mgd. It appears
therefore that the critical period over which a shortage could
develop is longer than one day. Whether the one-day peak consump-
tion would actually present any problems depends to a large
�J extent on the prior conditions which affect usage and therefore
the available storage prior to the onset of the peak day usage.
IMPACT OF WATER SHORTAGE ON WATER SYSTEM
J As outlined earlier the City' s distributin network consists
of three systems. These are East Hill, the Valley and the West
IIll Hill. The East Hill system has two pressure zones: the 590 and
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the 485 foot elevations. The Valley system has one pressure zone
at 240 feet. The West Hill also has two pressure zones: the 529
and the 354 .5 foot elevations. The sources of supply are located
east of the City. The systems that receive the water first are
therefore the East Hill and the Valley system. The Clark Springs
transmission main discharges into the 416 ' elevation tank on
James and 98th Ave. S . E. and the Kent Springs main discharges
into the 240 ' elevation Scenic Hill reservoir.
From the 416 ' elevation tank on James and 98th water gravi-
tates to the 218th Street reservoir at elevation 240 feet , to
feed the Valley system. The Valley system supplies pump station
#3 which supplies the lower pressure zone of the West Hill at
elevation 354 . 5 . From this elevation pump station #4 supplies
the higher West Hill zone at elevation 529 .
The two pressure zones of the East Hill system on the other
hand are supplied by pump station #5 which draws water from the
416 ' elevation tank on James and 98th and pumps into the 125 ,000
gallon tank at elevation 485 feet to supply the lower pressure
zone and into the other 1 mg and 3 . 5 mg tanks at elevation 590
feet to supply the higher pressure zone.
The 218th Street reservoir which is fed by gravity from the
James Street reservoir is programmed such that it calls for
water whenever the tank is four feet below the full stage irrespec-
tive of how much water the James Street reservoir may contain.
The least amount of water the 218th Street reservoir will have is
therefore four feet below the overflow line. Such being the case
54
the Valley System and consequently the West Hill System are
almost always assured of water unless the James Street reservoir
runs dry. The implications of this arrangement is that the
Valley and West Hill Systems will receive a priority for water
and the system which will experience the shortage first is the
East Hill system. Should the shortage persist however to the
point where the James Street reservoir will run dry it will not
be too long before the 218th Street reservoir will be drawn down
too.
In the long run none of the three systems with their respec-
tive pressure zones will be any worse off than any other system
should a long-term shortage develop. Furthermore, should a
shortage develop it is likely to be caused by higher consumption
figures throughout the service area mainly due to hot and dry
weather conditions and not due to localized conditions in
any one particular area. But upon the onset of a shortage
the East Hill and Water District 111 will be the first areas
to experience it unless the 4 . 5 mg. storage capacity proves
to be adequate to make up the shortage until supplies are
replenished.
SOURCES OF ADDITIONAL SUPPLY
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To avoid a possible recurrence of past water shortages,
additional supply must be provided in a quantity which will meet
existing demands with a margin of safety, and have the capability
of expansion for a rapidly growing population. Also, the additional
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supply must be "on line" by the summer of 1980. Following is a
description of present and potential water supplies.
City of Seattle Intertie - Valley System - .
The City of Seattle has water readily available to meet the
City 's short-term and long-term needs. This supply could be
obtained directly from the Bow Lake pipeline on approximately S.
160th St.
Tapping the Bow Lake pipeline would require the installation
of 16" main from S. 160th St. to S . 180th St. , and would con-
stitute a permanent , long-term commitment.
The project of tapping the Bow Lake pipeline could be
initiated by a pre-design report. An important consideration,
from the standpoint of operation, would be the extent to which
the City would feel it is necessary to supplement its existing
and projected sources with Seattle water. A specific area could
be isolated and served entirely with Seattle water, or used on a
supplementary basis for meeting peak demands. The latter method,
because of surcharge costs associated with supplying peaks, would
likely result in costs comparable to isolating a specific area.
Also, it would not provide the relief needed for the City to
formulate plans, and develop sources in a reliable and economical
fashion. The amount needed in accordance with projections
contained in this plan is 6 mgd.
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Kent Springs
The Kent Springs source has a calculated production capacity
of approximately 3600 gpm at present, with both of the new
pumps running . The geologist' s report indicates that two
additional wells can be developed on the site with a substantial
increase in the supply rate. However, as noted previously, the
existing transmission lines are delivering at capacity under
gravity conditions, and it would be virtually impossible from an
operational standpoint to pressurize the Clark Springs main with
water from the Kent Springs source. Hence► while the Kent
Springs source should be fully developed for the long term
potential, the time needed for development and analysis, and the
extent of improvements needed to bring it "on line" exclude it as
a short term ( 1 to 3 years) solution. Augmenting the Kent
Springs as a source of supply is a long-term solution which can
be realized only by the replacement of the Kent Springs transmis-
sion main with a large diameter pipe which can carry the full
potential of the Kent Springs source which could amount to over
10 mgd. Furthermore a new transmission main from Kent Springs
would free the available capacity in the Clark Springs main
which is presently being utilized by the Kent Spring source
through an intertie between the two mains.
Another advantage which may be realized by a new Kent
Springs transmission main is that such a main could also be sized
to pick up 2 more mgd from Armstrong Springs. The proper capacity
may then be in the range of 12-14 mgd.
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The construction of this main should be completed by the
Spring of 1984 . _
Clark Springs
The City has two sources of supply; one on Rock Creek at
Clark Springs, and the other at Kent Springs. At present, the
Clark Springs source produces approximately 2800 - 3200 gpm, or
slightly over 4 mgd. While there is a possibility that this rate
of supply can be increased, no information has been developed
which indicates that the increase could be significant.
Armstrong Springs
The City is presently purchasing the Armstrong Springs site.
Test drilling indicated a potential supply of approximately 2
mgd. If this source is developed, this amount can be supplied on
a long term basis and transmitted to the City by the new Kent
Springs transmission main.
East Hill Community Well
A study prepared in 1975 by SEA, Inc, for the East Hill
Community Well Company refers to well pumping tests conducted
in 1966 by Mr. Richard J. Rongey, Consulting Geologist. These
tests were made on the Well Company' s existing wells, and predict
that as much as 3 .9 mgd could be produced from the existing well
and a new well which could be developed. The SEA, Inc. , report
recommends negotiations with the City, using the Well Company' s
supply potential as a means of obtaining fire protection from the
City.
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The Geologist' s report quoted by SEA, Inc. , indicates that
the two existing East Hill wells are capable of producing 0 .9
mgd, and that a new well could be drilled with an estimated
capacity of 3 mgd. Additional testing of the existing wells, and
a new test hole would be needed to substantiate these quantities.
Also, discussions with the Well Company officials would determine
the desirability of entering into an agreement, should the
testing substantiate the predicted yield of this source. It
should be noted that this source has the potential of short-term
development due to its location with respect to the City' s
system.
Also, it should be noted that since the Rongey report
indicates the presence of a substantial aquifer on the East Hill,
the development of a well source by the City, independent of the
East Hill Community well system is a distinct possibility.
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City of Seattle Interties - Valley System and East Hill System
Interties with the City of Seattle can be constructed in two
other locations other than the Bow Lake Line. One is in the
valley Cedar River Pipeline #5 to where Seattle is proposing the e P
go through the valley up the West Hill to the proposed 14 mg tank
on Military Road and 38th Avenue S.E. The pipeline will be built
in 2 stages. The first stage will extend from the source to the
J valley where it will terminate in the vicinity of S.E. 224th
Street and 76th Avenue S.E. This stage is scheduled to be
completed in 1986 . The second stage is from the above location
to the tank and this stage is scheduled to be completed in 1995.
59
Kent may tap this pipeline any time after 1986 . The amount
needed according to the projections contained in this plan is 7
mgd.
Another potential source of supply is a future line which -
may run along 132nd Avenue S.E. The line would be constructed by
the City of Seattle as an intertie with the City of Tacoma
system. Contact with the City of Seattle indicated that the line
is in the Long range planning stage where construction may be
completed by 1990 if the demand materializes. The amount needed
according to projections made in this plan fall between 5 and 10
mgd and will be needed by the year 2000.
City of Tukwila Intertie
Another source which could present a short-term solution is
an intertie with the City of Tukwila. Either of these two
interties would have a low initial cost but a high on-going
cost since the cost of water to the City of Kent may be about 33
cents per 100 cu. ft. By comparison the City of Kent supplies
Water District 111 at a rate of 15 cents per 100 cu. ft.
As of the present the City of Tukwila is agreeable to an
intertie and an agreement may be executed in time to meet the
1979 summer demands.
Contacts with the City of Tacoma have shown that due to
arrangements agreed upon between Tacoma and Seattle, the City of
Tacoma cannot supply Kent with water without first getting a
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release from Seattle since Kent falls within Seattle' s service
area. The dividing line is S.E. 272nd Street. North of this
line is served by Seattle and South of it is served by Tacoma.
The Kent service area lies substantially north of S.E. 272nd
Street. Further Tacoma will have no water until 1986 at the
earliest.
City of Renton
Presently the City of Kent has an intertie with the City of
Renton. But since the pressure of the City of Renton' s system at
196 feet is lower than that of the City of Kent ' s at 240 feet,
water must be pumped up to the Kent' s system. In order to bring
in substantial amounts of water into the Kent system a pump
station must be constructed. Contacts with the City of Renton
indicated that there may be available to the City of Kent water
'in the amount of 2-3 mgd for the summer of 1980. The cost of
water is likely to be in the range of 25 cents per 100 cu. ft.
This pump station could be on line in the spring of 1980.
CLASSIFICATION OF SOURCE OF ADDITIONAL SUPPLY
Using the consumption and production figures presented
earlier it appears that the City may experience a shortage of 2. 0
Jto 2. 5 million gallons per day. The shortage may last for
several days depending on weather conditions . It also appears
that the impact of the shortage will be experienced throughout
J the service area and not necessarily in one particular area.
61
To make up the shortage, several options have been presented.
The options may be classified into two categories: short-term
solutions and long-term solutions. There are two long-term
solutions which may meet the City's needs until the year 1990.
One is the full development of Kent Springs, assuming that the
supply is available and a new transmission main is constructed
and the other is an intertie with the City of Seattle through the
Bow Lake main assuming the contractual conditions are mutually
agreeable to both parties.
The other sources of additional supply can only meet the
City' s needs over the near future before increased demand due to
growth will overrun these new sources of supply.
COST COMPARISON: CITY OF SEATTLE VS CITY OF KENT 'S SOURCES
The cost comparison which will follow is between developing
the City' s full potential at Kent Springs and Armstrong Springs
which could produce 7 more mgd or importing sufficient amounts
from the City of Seattle to meet its needs over the next 10 years
or more in the Valley and West Hill areas . The City ' s present
sources would then in time be used up by the East Hill and Water
District 111 's systems.
Under this scenario the City needs not to develop further
its own sources but to keep importing from the City of Seattle in
increasing amounts as the demands of the Valley and West Hill
systems increase in time. The 1990 projection for these two
62
systems shows that the consumption will amount to 6980 gpm or 10
mgd during a 3-day peak period. The average daily consumption
during the peak month would amount to 4990 gpm or 7.2 mgd. To
absorb this quantity of water the Valley system's transmission
capacity must be increased. Initially an intertie consisting of
a 16" main will have to be constructed along E. Valley Highway
from 160th to 180th Street S.E. for a length of 6600 feet. As
increasing amounts of water are needed other improvements would
be necessary. These improvements may consist of 9600 feet of 16"
main to form a loop where the mains would run along the E.
Valley highway and the West Valley Highway connected at 180th
Avenue S.E. Other system improvements may be necessary such as
meters valves, etc.
On the other hand to develop the City's full potential the
Kent Springs transmission main must be replaced, two new wells
drilled at Kent Springs and a well and a pump station and a short
transmission main built at Armstrong Springs to get the output of
the Armstrong Springs well into the new Kent Springs transmission
main.
JThe cost comparison will be based on the cost per hundred
cubic feet (unit) delivered to consumers taking into consideration
Jthe initial costs spread over the expected life of the facilities
and the estimated maintenance and operations cost.
63
City of Seattle alternative - Cost Analysis
16200 feet of 16" main, Project Cost: 583, 000
Meters, valves and other appurtenances = 60,000
Total Initial Cost = 643, 000
Estimated life of main = 50 years
Estimated life of other facilities = 20 years
Assume an interest rate of 8%
Annual cost of main = . 08174 x 583,000 = 47,650 _
Annual cost of meters and valves = . 10185 x 60, 000 = 6 , 110
Annual M & 0 cost on mains at 1 % of capital cost = 5,830
Total annualized capital cost = $62 ,600/yr.
Assume average rate of water purchase over the next 11
years, i.e. , until the year 1990 on an annual basis to be 5
mgd.
Annualized capital cost per 100 cu. ft. _
62,600 x 7. 5 x 100 x 100 = 2. 5 cents
5 x 365 x 1000,000
Cost of water purchase per 100 cu ft = 17. 5
Total cost per 100 cu. ft. = 20 cents
Development of City's Own Sources - Cost Analysis
Kent Springs Main:
10 ,000 feet of 24" , Project Cost = 500,000, 40,000 feet of
30" , Project Cost = 2,600,000
Total Project Cost = $3, 100,000
Two wells at Kent Springs; Project Cost = $120,000
One well, Pump Station and main at Armstrong Springs = $200,000
Other system improvements - 10 ,000 feet of 16" main =
360,000
Assume life of wells and Pump Station to be 25
years
Assume life of main to be 50 years
Assume an interest rate of 8.0%
Assume the Kent Springs main will carry on a year - round
basis an average of 10 mgd.
Annualized Cost of Kent Springs Main:
.08174 x 3 , 100,00 = $253,400
Annualized Cost of 2 Wells:
. 09368 x 120 ,000 = $11 ,240
Annualized Cost of Well and Pump Station;
. 09368 x 200,000 = $18,740
Annual M & 0 Cost on Wells and Pump Station at 5% of Capital
Cost;
5% of 320 ,000 = $16 ,000
Annualized Cost of Other System Improvements;
0. 08174 x 360,000 = 29,400
Annual M & 0 Cost on Mains 1 % of Capital Cost
. 01 x (3 , 100, 000 + 360,000) = 34 ,600
Total Annual Cost = $363 ,400
Cost per 100 Cu. ft. = 363 ,400 x 7. 5 x 100 x 100 = 7 . 5 cents
10 x 365 x 1 , 000, 000
64
The above calculations show that the total cost of the City
of Seattle ' s Water is 20 cents per 100 cu. ft. , while the City' s
own water developed and transmitted amounts to 7. 5 cents per 100
cu. ft. based on the assumptions outlined above.
Furthermore 87% of the total cost of the City of Seattle' s
water ( 17.5 cents out of 20 cents) is in the form of direct
purchase. This cost is likely to escalate commensurate with
overall inflation rate. Developing the City' s own resources
on the other hand is substantially a one-time cost which will not
be repeated and therefore is not subject to an inflationary
increase in the future.
The costs presented above are considered current cost,
adjustments should be made to allow for cost increases for future
construction.
COST ANALYSIS OF OTHER SOURCES OF SUPPLY
In this section cost estimates of the other additional
sources of supply discussed earlier in this chapter will be
�j provided. Those sources will not supply the long term needs of
the City over the long run i.e. , until 1990. Those sources if
and when developed will bridge the gap between supply and consump-
tion over a short period of time. The only long-term solutions
are either the purchase of water from the City of Seattle or the
J
rJ
65
development of the City' s own sources at Kent Springs and Armstrong
Springs which would necessitate the construction of a transmission
main as outlined earlier.
The other sources are the following: _
City of Tukwila; Project Cost: 60,000
The purchase price of water is presently set at 33 cents per 100
cu. ft. This source would supply the City of Kent with at least
2 mgd. The total cost per 100 cu. ft. may be calculated as follows:
Annualized Capital Cost
0 . 10185 x 75,000 = $7,650
Annual M ' 0 at 5% of Capital Cost - 3 , 000
Total Annual Cost = $11 ,400
Cost Per 100 Cu.Ft. = 33 + 10, 650 x 7. 5 x 100 x 100
2 x 365 x 1 ,000,000
= 33 + 1 . 1 = 34. 1 cents
East Hill Well :
Well and Pump Station; Project Cost = $240,000
Annualized capital cost;
. x 0 . 09368 x 160, 000 + 0. 10 , 185 x 80,000 = $23, 100
Annual M & 0 Cost for Pump Station at 5% of Capital Cost
. 05 x 80 ,000 = 4 ,000
Total. Annual Cost = $27 , 100
Assuming this source would supply an average of 1 mgd
continuously. The cost per 100 Cu.Ft. may be calculated
27 , 100 x 7.5 x 100 x 100 = 5. 5 cents/100 cu. ft.
1 x 365 x 1 , 000, 000
The other sources, namely the development of two wells at
Kent Springs and a well at Armstrong Springs have been presented
earlier.
66
City of Renton
Pump Station and Appurtenances: Project Cost = $40,000
Annualized capital cost;
1 0 . 10185 + 40,000 = $4, 100
11 Annual M & O @ 5% of capital cost = $2,000
Total annualized Capital Cost = $6 , 100
1 6 , 100 x 7.5 x 100 x 100
= 1 cent
2 x 365 x 1 ,000,000
1 cent + 24 cents (direct cost of water) = 25 cents/100 cu. ft.
SUMMARY
- The following table presents a summary in tabular form of
the additional sources of supply:
:J
J
J
67
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68
VII . SYSTEM'S FUTURE NEEDS AND
ALTERNATIVES TO MEET THEM
(WATER SYSTEM PLAN)
GENERAL
Based on the information developed so far it appears that
the most critical needs of the City' s water system are related to
developing new sources which will meet the present shortage as
well as the demands of the system until 1990 . By 1990 the system
will have to provide up to 10 mgd for one-day peak usage above
and beyond what it can provide at the present time. Developing a
source or sources which can provide this quantity of water will
neccessitate the provision of the necessary transmission, storage
and pumping facilities to get the water to the consumers through-
out the servi
ce area
The needs of the system ar
e therefore the
deve
lopment ment of additional supplies and the capability to deliver
them to the consumers.
Once the City is committed to an alternative source of
supply the other facilities, namely transmission, storage, and
pumping facilities, must be provided at locations and elevations
to meet those requirements dictated by the source. The remainder
of this chapter will discuss the source of supply and associated
facilities to meet the future needs of the service area.
J
SUPPLY SOURCES
The City' s present needs exceed its supply capability by
about 2 mgd for a peak 3-day usage. Over the short run, i.e. ,
69
J
over the next two or three years , this shortage is likely to
almost double to about 4 mgd for a peak three-day usage. In time
and as a result of growth the City 's needs will increase and by
1990 the system must provide 16.2 mgd for a peak three-day usage
or 17 .4 mgd for a peak one-day usage. These figures will result
in the need to provide 8.7 mgd for a peak 3-day usage or about 10
mgd for a peak one-day usage by 1990 assuming the present capacity
of the system is 7.5 mgd.
Based on the above, the City 's needs may be classified as
short-term needs, i.e. , up to two or three years and long-term
needs which extend until 1990 .
Short-Term Supply Sources
There are a number of sources which meet the City 's needs
for the short term, i.e. , over the next two to three years.
These sources have been outlined in the source analysis chapter
and consist of interties with the City of Tukwila, Water District
No. 75, the City of Renton, Water District 58 and the East Hill
Well.
Excluding the East Hill Well, the City would purchase the
water from the other sources as the need arises to supplement the
City's present own sources. The intertie with the City of
Tukwila is presently in the design stage and could be on line
by October 1979. This intertie could provide the City with
2 mgd. The intertie with Water District No. 75 is existing and
water may be purchased to supplement the City 's needs for several
70
days during high usage. The pressure gradient for both the City
of Tukwila and Water District 75 is higher than the City of
Kent' s system and water may gravitate into Kent' s system. As for
the City of Renton, it is possible to withdraw water from the
City of Renton' s system but it has to be pumped into the Kent' s
system. The last time the City of Kent purchased water from the
City of Renton was in the summer of 1977 .
Water District No. 58 could potentially supply the City of
Kent with water through an existing 6-inch connection in the
vicinity of SE 227th Place and 116th Avenue SE. The gradient of
Water District No. 58 is at approximately 605 feet as compared to
590 for the City of Kent. It is not known for certain as to how
much water can be withdrawn from the system of Water Distict No.
58 but could be in the range of 500 gpm or 0 .7 mgd. Without
hydraulically analyzing the system of Water District No. 58 it
would be difficult to estimate how much water may be withdrawn
y
without creating undesirable effects on the Water District No. 58
system.
Another possibility relating to Water District No. 58 is the
construction of an intertie between Water District No. 111 and
Water District No. 58. Through contacts with the City of Seattle
and Water District No. 58 this source has proven to be not
Jfeasible.
The only short-term supply source which would not necessitate
the purchase of water from other sources is the East Hill Well
which is presently in the development stage. If the expected
4� 71
yield materializes it could produce between 2 and 3 mgd. This
source is expected to be on line by the spring of 1980.
Among the sources presented above, the Tukwila Intertie and
the East Hill Well are considered the most effective in supple- _
menting the City's needs on a short-term basis. These two
sources could possibly provide up to 4 mgd. The intertie, with
Water District No. 75, may be utilized but this source has in the
past shown to be not fully responsive to the City's needs. The
intertie with the City of Renton is viewed as a source of supply
only as an emergency measure due to the need for pumping. Water
District No. 58 can possibly supply 500 gpm. This figure is by
no means certain and it could considerably less depending on the
hydraulic characteristics of the Water District 58 system.
Based on the above, the two sources of supply which should
be pursued to completion for meeting the City 's short-term needs
are the East Hill Well and the Tukwila Intertie.
Long-Term Supply Sources
Two sources of supply are potentially available to the City
to meet its long-term needs until 1990. These are the City 's own
sources at Kent Springs and Armstrong Springs on the East Hill
and the City of Seattle. These sources have been discussed
previously in the Source Analysis Chapter and a cost analysis
provided. It was determined that the cost of developing the
City ' s own sources is 7.5 cents per 100 cubic feet ( 100 dollars
per million gallons ) while the cost of purchasing the water from
72
Seattle is 20 cents per 100 cubic feet (267 dollars per million
gallons) .
Although the cost factor is an important one the alternative
of developing the City' s own sources is dependent on other
factors which are the condition of the Kent Springs Main and the
recent investment which the City has recently made at the Kent
Springs site.
The Kent Springs main is about 50 years old and it is
believed that a substantial amount of water is lost through it
due to leakage. Therefore, in order for the City to protect its
recent investment in Kent Springs, which amounted to approximately
$600,000 , and in order to deliver the 5 .4 mgd from the two existing
wells, a new 21-inch transmission main is needed. By oversizing
4
the main to 30-inch diameter an extra 8 mgd may be delivered. By
y� oversizing the main the needs of the City may be met until 1990 .
In order to obtain the extra water, 2 more wells will be drilled
at Kent Springs with a total capacity of 3,600 gpm and a well at
j Armstrong Springs with a capacity of 1 ,400 gpm for a total of
J 5,000 gpm or 7 .2 mgd.
tJ Based on the above discussion and material previously
developed in the Source Analysis Chapter it is recommended that
the City develop its own sources as outlined above as a long-term
source to meet its needs until 1990 .
J
73
TRANSMISSION MAINS
Among the proposed transmission facilities the Kent Springs
main is the largest in terms of size and cost. It is about
50,000 feet in length ( about 9 .5 miles) 40,000 of which will be 30
inches in diameter and 10, 000 will be 24 inches in diameter. The
30-inch portion will extend from the source at Kent Springs to
114th Avenue SE where a reservoir is to be located . The head
loss through the 30-inch main was the determining factor in
arriving at the 30-inch size. The head loss had to be kept to a
minimum so that enough residual pressure remains in the main to
deliver the water past the highest point along the route which
happens to be in the vicinity of 114th Avenue SE. Assuming a
flow of 13 mgd a 30-inch diameter main will deliver such flow
past 114th Avenue SE with about 30 feet of head left. The next
size down, i.e. , 27-inch will not meet this objective and a pump
station will have to be provided. In order to avoid pumping, a
30-inch main would be necessary. The provision of a pump station
in order to reduce the pipe size by 6 inches is not cost effective
and should not be considered any further.
The other transmission mains are provided throughout the
system to create a network capable of supplying the City' s needs
into the future. The transmission network is shown in the
enclosed map.
STORAGE AND PUMPING FACILITIES
The storage requirements for the East Hill system, the
Valley system and the West Hill system will be analyzed in terms
74
of three components which, when added up, consitute the total
storage required for each of these systems. The individual
components are fire flow, standby and flow equilization. The
magnitude of each of those components depends on the specific
conditions of the water system serving the particular system in
question, although the design standards provided by the Department
of Social and Health Services provide a framework for calculating
the total storage required. The procedures provided by the DSHS
standards will be followed and applied to each of the three
systems in calculating the required storage.
The storage provided is often times contained in standpipes
where the high water surface elevation reaches the service
elevation for the area in question. Under such conditions the
water contained in the lower segment of the storage reservoir can
be delivered to consumers at a low pressure and in some areas due
to transmission losses cannot be delivered at all or at extremely
low pressures. In accounting for storage provided the bottom 40
feet of all standpipes is of such limited usefulness, it may
safely be assumed that it is unavailable. As a result of this
assumption, slightly conservative and therefore, safer results
are derived.
East Hill System
The storage required for the East Hill system will include
the 590 and 485 pressure zones but not the Water District No.
111 system, since Water District No. 111 will provide its own
storage part of which is already contained in the 3 .5 mg tank on
SE 284th Street and 124th Avenue SE.
75
Fire: 5,000 gpm for 5 hours = 1 , 500 ,000 gallons
Standby: 1 ,750 gpm x 24 x 60 = 2, 500 ,000 gallons
Equalizing: Use Graph No. 10 provided in the Design
Standards of DSHS and the peak day
consumption of 3 ,230 gpm
15 x 0 . 72 x 60 x 3 ,200/2 = 1 ,000 , 000 gallons
Total storage required is 5 mg.
Total Storage Provided:
3 .5 mg tank: 3. 5 x .57 x .6 = 1 . 2 mg
1 .0 mg (Blue Boy) 1 x . 6 = 0 . 6 mg
Storage Needed = 5.0 - 1 . 8 = 3 . 2 mg
Provide 1 mg for the 485 foot system and 3 mg at an inter-
mediate level with auxiliary power so that the tank may satisfy
the storage requirements.
1 mg x . 6 = 0 .6 mg
3 mg at 100% = 3.0
Total storage to be provided = 3. 6
Total storage which will be available to the East Hill
system after constructing a 1 mg tank at the 485 foot elevation
and a 3 mg tank at an intermediate level with auxiliary power at
3. 6 + 1 . 8 = 5. 4 mg vs. a 5 mg requirement.
The two tanks are to be constructed at the time the Kent
Springs main is built but no later than 1984 .
The location of the two tanks is shown on the attached map
which shows all the other proposed improvements.
76
Aside from meeting the storage requirements the two tanks
are planned to accommodate all the future flow coming from Kent
Springs and Armstrong Springs via the proposed Kent Springs
transmission main. Under this arrangement the transmission main
would discharge into the proposed 3 mg in the vicinity of 114th
Avenue SE at an approximate water surface elevation of 425 feet.
A pump station with auxiliary power would be constructed at the
same site. The pump station would pump to another proposed tank
in the vicinity of SE 267th Street and 100th Avenue SE with a
ll water surface elevation of 485 feet to serve the 485 foot East
! ! Hill system and also into the 3. 5 mg tank at the 590 system.
P � In terms of the method of operation, this arrangement would
be almost identical to the Clark Springs Main - 416 foot James
Street tank and Pump Station No. 5 and will be operated in a
similar fashion.
The pump station would contain three pumps, one of which
Jwould pump into the 485 system; one into the 590 system and the
Jthird pump which would have a dual speed would pump into either
elevation. The third pump would also serve as a standby to meet
the needs of either pressure zone during fire or peak demand.
The Valley System
' The storage required for the Valley system may be calculated
Jas follows:
Fire: 5, 000 gpm for 5 hours = 1 ,500 ,000 gallons
Standby: 3,000 x 1 ,440 = 4 ,300 ,000 gallons
Equalization: 15 x 0 .72 x 60 x 6,450/2 = 2 , 100 ,000 gallons
Total storage required is 7.9 mg; Use 8 mg.
77
Storage, provided by the Scenic Hill and 218th Street
Reservoirs, is 9 mg excluding the James Street Reservoir. No new
storage is, therefore, needed for the Valley system.
The West Hill System
The storage requirements for the West Hill system may be
calculated as follows:
Fire: 2, 500 gpm for 2.5 hours = 375 ,000 gallons
Standby: 450 x 1 ,440 = 650 ,000 gallons
Equalization: 15 x 0 . 72 x 60 x 1 ,250/2 = 405,000 gallons
The total storage required is 1 , 430,000 .
The storage provided at the present time is 300 , 000 gallons.
Assuming the proposed 1 mg tank on 38th Avenue and Military Road
would be on line by the end of 1979 , it will provide a storage
volume of 1 mg. This leaves a shortage of 130 ,000 gallons which
can for practical purposes be ignored since the area is expected
to grow at a lesser rate than the rest of the service area. The
West Hill service area is fairly limited in size and much of it
has already been developed. The proposed 1 mg tank together with
the existing 300 ,000 gallon tank should be adequate until the
year 1990 and probably beyond. Should these growth trends change
in the future the storage requirements may be evaluated.
SUMMARY
The needs of the water system of the City of Kent over the
next ten years or so include every major type of facility includ-
ing source development, transmission mains, distribution mains,
storage and pump stations.
78
The Armstrong Springs source should be further developed by
drilling a 1400 gpm well.
A new transmission main connecting the Kent Springs source
with the Scenic Hill Reservoir consisting of about 40,000 feet of
30-inch pipe and 10 ,000 feet of 24-inch pipe, should be con-
structed. The main would pick up the Armstrong Well along the
way. The main would first discharge into new 3 mg reservoir to
be located in the vicinity of 114th Avenue SE and SE 267th Street
with a water surface elevation of approximately 425 feet. A new
pump station would pump to a new 1 mg tank to be located in the
vicinity of 100th Avenue SE and SE 267th Stret with a WS elevation
of 485 feet to serve the low East Hill system. The same pumping
facility would also pump to the 590 system. The rest of the
water would then gravitate through the 24-inch portion of the
r main to the Scenic Hill Reservoir to serve the Valley system.
The only improvements which the Valley system needs is a
series of mains ranging from 8-inches to 16-inches in diameter.
JThese proposed mains are shown in the attached map.
The West Hill system needs a 1 mg standpipe to be located on
38th Avenue and Military Road at the City of Seattle site. This
tank would serve all of the upper West Hill system but it is
especially useful for the north portion of the West Hill.
These facilities are predicated on growth trends presented
earlier in this report. Should these trends change, i .e. ,
accelerate or slow down to an appreciable degree the timing as to
the construction of those facilities should be reexamined .
79
VIII . IMPLEMENTATION PROGRAM
In this chapter all the projects to be constructed over the
next twenty years will be listed and prioritized . Cost estimates
of all the projects as well as phasing and scheduling will be
provided. The costs provided are considered current costs
( summer of 1979 ) . An increase of 10 to 12 percent per year
should be added to each project where construction would take
place after the summer of 1979 . The costs provided include the
cost of services, i.e. , complete project costs.
LIST OF PROJECTS AND COST ESTIMATE
This list will cover source development, including interties
with adjacent purveyors, transmission mains, pumping facilities,
storage facilities, and distribution mains 12-inches and larger.
Distribution mains 10-inches and smaller will not be listed or
costed out since the cost of such mains is normally borne by the
developer. Although in some instances a developer may be required
to provide a 12-inch main, it will be assumed that the City will
=� provide these mains in order to complete large scale loops.
Should the City not construct any 12-inch distribution mains at
the City' s expense, the City' s financial commitments would then
w.J be on the conservative side.
U
80
J
Tukwila Intertie $ 60 , 000
East Hill Well 240 ,000
Seattle Intertie Pre-design report 26 ,000 _
Seattle Intertie Design and Const. 650 , 000
Test wells at Kent Springs 65, 000
Armstrong Springs, one well
One pump station and force main 200 ,000
Financial Report and Rate Study 24 ,000 =
Develop 2 wells at Kent Springs 125, 000
Source Development
2nd Seattle Valley Intertie 250 ,000
Sea-Tac E. Hill Intertie 250 ,000
Subtotal $1 ,912 ,000
Source Transmission
Kent Springs Main
10 ,000 ' of 24" @ $56/ft. $ 560, 000
40 ,000 of 30" @ $66/ft. 2 ,640 ,000
Subtotal $3 ,200 ,000
Pumping Facilities
One pump station at 114th Avenue SE
and SE 267th Street with Auxiliary
Power and 3-1750- gpm pumps $ 300 ,000
Subtotal $ 300, 000
Storage Facilities
East Hill
1 -3 mg tank, 20 ' high and
160 ' dia. , near 114th Avenue SE
and SE 267th Street $ 850 ,000
East Hill
1-1 mg tank, 120 ' high and
38 ' dia. , near 100th Avenue SE
and SE 267th Street $ 475 ,000
West Hill
1-1mg tank, 85 ' high and
45 ' dia. , near 38th Avenue
and Military Road $ 450 ,000
Subtotal $1 ,775,000
81
Distribution Mains
16" Diameter - 25 , 0001 at $40/ft. $1 ,000,000
12" Diameter - 43, O00 ' at $33/ft. 1 ,420,000
Subtotal $2,420,000
TOTAL ALL FACILITIES $9,612,O00
PHASING AND SCHEDULING
As a general rule the construction of any facility should
not be undertaken unless the need for it materializes. This is
especially true for distribution mains. Based on this assumption
the distribution mains will neither be prioritized nor a date set
for their installation. Other facilities will be scheduled based
on the time the need for those facilities materializes . The
following is a tabular listing of facilities and the timing of
the completion of design construction. The projects are listed
in a chronological order and organized in four phases. These
are:
J1 . The immediate phase where projects are to be completed
in 1980 with the exception of the Seattle Bow Lake Line
JIntertie which may be completed in the Spring of
i 1981 .
2. The short-term phase where projects are to be completed
by the spring of 1984.
3 . The intermediate phase where projects are to be com-
pleted by the spring of 1990.
l4 . The long-term phase where projects are to be completed
by the year 2000.
82
r
TABLE 10
LIST OF PROJECTS AND CONSTRUCTION SCHEDULE
Immediate Phase: To be completed by April 1980.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase -
East Hill Well 240,000 Spring ' 80 May 180
Tukwila Intertie 60,000 Spring ' 79 October 179
Well Testing at 65,000 Fall 179 Spring ' 80
Kent Springs
Construct Intertie 650,000 Fall 179 July ' 80
w/Seattle
Construct West Hill 450,000 Fall ' 79 June 180
1 MG Tank
Kent Springs Pre- 27 ,000 Spring ' 80
Design Report
Financial Report & 24,000 Spring 180 ---
Rate Study
Seattle-Kent Intertie ---
Pre-design report 26 , 000 Winter 179 ---
TOTAL COST $1 , 542, 000
Short-Term Phase: ( 1980-1984 ) To be completed during the period
1981-1984.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Kent Springs Main 3,200,000 Oct. ' 79-Apr. ' 80 181 , - 82, 183
2 Wells at Kent 125,000 1981 1982
Springs
East Hill 3 MG 850,000 1982 1983
Tank
East Hill 1 MG 475,000 1983 1984
Tank
Develop Armstrong 200,000 1983 1984
Springs
East Hill Pump 300,000 1982 1983
Station
TOTAL COST $5, 150, 000
Intermediate Phase: ( 1985-1990) Projects to be completed by 1990.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Seattle-Kent 2nd 250, 000 1989 1990
Intertie at 224th
& 76th Avenue
83
TABLE 10 (Continued)
LIST OF PROJECTS AND CONSTRUCTION SCHEDULE
Long-Term Phase: ( 1990-2000) Projects to be completed prior to
the year 2000.
Estimated Design Complete
Project Proj . Cost Phase Const. Phase
Kent Intertie w/ 250,000 1995 1996
Seattle-Tacoma
line of 132nd
Ave. S.E.
Total All 7, 192,000
Phases
Post-Storage
Transmission 2,420,000
Mains
$9,612,000
The first three projects shown at the top of the list are
presently underway and they should be operational by the spring
of 1980. The first two are to meet the short-term supply needs
of the City. The third project is to meet a critical supply and
pressure condition on the West Hill and improve fire protection.
One of the major projects to meet the City' s long-term needs
is to conduct well testing at Kent Springs to measure the amount
of water available at Kent Springs. if positive results are
.� obtained, the Kent Springs transmission main should be designed.
Should state or federal funds become available, efforts should be
made to secure as much grant funding as possible. Whether grant
funds are obtained or not the project should be constructed over
I ' a three-year period so that it should be fully completed by no
�J
later than the spring of 1983 . By then the short-term supply
�J
84
sources would have been used up due to growth in the service area
and the Kent Springs source would be on line.
The Armstrong Well should be brought on line by the spring of
1984 to coincide with the completion of the Kent Springs main. -
By the time the Kent Springs transmission main is completed
the East Hill 3 mg tank and pump station should also be completed,
so that the East Hill area' s additional needs may be met. The
East Hill ' s 1 mg tank may be constructed next.
In the meanwhile distribution mains may be constructed on an
as-needed basis, since it is difficult to predict which areas
will develop first to the extent requiring large 12-inch or
16-inch mains. Mains of 10-inch size and smaller are assumed to
be paid for by developers and therefore they do not enter the
financial picture as far as the City is concerned.
85
CHAPTER IX
COMPATIBILITY OF WATER SYSTEM WITH OTHER PLANS
In this chapter, the Kent water system plan is discussed as
regards other plans and systems. Comprehensive, zoning and
sewerage plans, as well as adjacent water systems are described
in relation to the water system plan to establish the compatible
nature of their objectives.
COMPREHENSIVE PLAN
The goals and policies of the City of Kent, as stated in the
City' s 1977 Comprehensive Plan, are in accord with the water
system plan. The objectives listed call for efficient water
facilities, coordination of service with adjacent water purveyors,
4� implementation of a comprehensive water plan, providing adequate
water supplies for fire protection, developing an equitable rate
structure and developing water systems based on land use plans.
!d The water system plan is in agreement with these objectives and
with the land use map contained within the Comprehensive Plan.
No system development plans or proposed line sizes appear incon-
gruous with the usage envisioned for the areas they are to
serve.
ZONING PLAN
JReferring to the zoning map of the City, there are no
apparent conflicts between planned water system developments or
►�
line sizing and the zoning of the areas to be served.
t.J
86
SEWERAGE PLANS
A review of the City' s sewerage plan reveals no conflicts
between it and the water system plan. There are no areas
scheduled for water service without accompanying sewerage service. _
ADJACENT WATER PURVEYORS
The compatibility of the service area boundary is established
by the approval of the boundary by the King County Council on
October 23, 1973. In addition, a separate written service
boundary agreement exists between the City and Water District No.
111 .
The Kent water system is connected to four other water
systems through interties, two of which are active. Both Water
District No. 111 and Water District No. 87 receive water from
Kent through one-way interties, while the interties with Water
Districts No. 75 and 105 are inactive. The gradient in Water
District No. 75 is higher than that of the neighboring West Hill
System and could supply the West Hill if the intertie were
opened. The connection with Water District No. 105 was once used
to supply water to the district from the Clark Springs Transmis-
sion main.
Interties are possible with three adjacent purveyors, all of
which would supply water to the Kent system. An intertie with
the City of Tukwila system could be made with Kent 's Low Level
System, and Water District No. 58 has the same gradient as the
East Hill System and could supply water to Kent through an
87
intertie between them. It should be noted , however, that both
Tukwila and Water District No. 58 purchase water from the City of
Seattle, and water bought from them would be expensive. The
third purveyor is the City of Seattle itself, and it could supply
water to the Low Level System through an intertie with its Bow
Lake Transmission Main north of Kent. This would be less expen-
sive than purchasing water indirectly through either Tukwila or
Water District No. 58.
The City of Kent has already in existence a service area
agreement with Water District 111 . At the earliest possible time
the City should draft formal agreements with the other adjacent
purveyors with which the City has common boundaries or where
-� those boundaries fall within a distance of one half mile or less
` from each other. The other purveyors include Water District No.
58 , Renton, Tukwila, Water District No. 75, Water District No. 87
land Auburn.
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CHAPTER X
SYSTEM OPERATIONS PROGRAM
GENERAL
This chapter presents an operations program outline for the
City of Kent Water System. The chapter is divided into five
sections:
o System Management
o Maintenance Program
o Water Quality Monitoring
o Cross Connections Control
o Response to Emergencies
The following items are valuable references to supplement
the material in this manual and should be available for reference:
1 . A complete set of "as-built" plans of the system.
2. A complete set of "as-built" plans, submittal data and
.� shop drawings on all electrical and mechanical equipment
in the system.
3 . A complete set of manufacturer' s operation and maintenance
instructions.
J4. Reference Manuals:
JWater Distribution Operator Training Handbook, American
Water Works Association.
89
Emergency Planning for Water Utility Management,
American Water Works Association, AWWA No. 19.
Manual of Water Utility Operations, Texas Water Utilities
Association, Austin, Texas. _
Rules and Regulations of the State Board of Health
Regarding Public Water Systems, 1978 , State of Washington,
Department of Social and Health Services.
Accepted Procedure and Practice in Cross Connection
Control Manual, Pacific Northwest Section, American
Water Works Association, Second Edition, 1973 .
Water Operator Certification Regulations, 1978 , State
of Washington, Department of Social and Health Services.
MANAGEMENT AND OPERATION RESPONSIBILITY
The Kent Water System is operated and maintained by the City
of Kent Water Department. Names of employees certified as waterworks
operators by the State of Washington are listed below.
Water Distribution Manager 3
Stan J. Boden - Superintendent
Water Distribution Specialist 1
Stan J. Boden - Superintendent
Leland Fingerson
Stan Frager
Duaine Hager
William Hansen
Lindy Lindberg
Van Parker
Larry Rifenberick
Larry Stone
Tod Sullivan
Robert Watson
90
Cross Connection Control Specialist
Duaine Hager
William Hansen
PREVENTATIVE MAINTENANCE PROGRAM
This section will present a schedule of inspection and maintenance
for the major water supply facilities within the Kent Water System.
Detailed information regarding specific pieces of equipment is not
presented. Lubrication and maintenance instructions specified by
the manufacturers should be followed closely.
Sources
1. Weekly - Inspect pumps and chlorination equipment, record
flow meter readings and well drawdown.
Storage Reservoirs and Tanks
1. Weekly — Inspect fences, gates and locks, check tank exterior
for cracks or leaks, record water surface elevation and
collect water samples.
2 . Annually - Drain reservoir, clean sides and bottom if
necessary, and inspect interior surface for cracks and
leaks.
Pump Stations
1 . Weekly - Check doors and locks, record flow meter reading,
check pumps including the following items:
o lubricants
o seals
91
0 running amperage and pressures
0 proper operation of pump control valves
0 other items specified by manufacturer
Distribution System
1. Daily - collect representative water samples.
2. Annually - flush all deadend mains according to a
schedule throughout the year.
Valves and Hydrants
1. Annually - Check and operate all hydrants and hydrant
valves annually ( fire department) , operate all distri-
bution system valves:
0 close and reopen until valve seats properly
o clean valve box
0 log inspection on the form shown as Figure 4
2. Check operation of all pressure reducing valves and
pump control valves according to manufacturer' s recommen-
dations and make necessary adjustments.
Meters
1. Annually - calibrate all system flow meters (not including
service meters ) according to manufacturer' s recommendation.
Telemetry
The telemetry system employs primarily electronic components
which require no maintenance.
92
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Valve&Hydrant Inspection Form
Check One Location Condition Comments
Valve Hydrant Operable/Inoperable Valve Size
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Date Inspected by
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Figure 5
Valve Inspection Form
1. Annually - inspect and lubricate ( if necessary)
telemetry recording instruments and mechanical flow
meters.
In addition to the above scheduled inspections, more _
frequent checks should be made to monitor facilities having
temporary problems. Emergency response equipment and spare
parts inventory should also be checked periodically.
WATER QUALITY MONITORING
Federal and state regulations specify a minimum water
quality monitoring program for community water systems. The
state Department of Social and Health Services has the responsibi-
lity for enforcement of these regulations. The water purveyor
(the City) has responsibility for monitoring, reporting and
maintaining drinking water quality within its service area.
The regulations discussed in this chapter concern sampling
requirements, maximum allowable contaminant levels (MCL ' s) , and
required action if these levels are violated.
Contaminants in drinking water which must be monitored have
been divided into several classifications as divided in this
discussion. Primary contaminants are those which are directly
related to public health and violations of MCL ' s must be dealt
with rapidly. Secondary contaminants are related to the aesthetic
quality of the water and do not directly affect public health.
Table 9 summarizes monitoring requirements.
94
Written notice to customers is required by federal and state
laws for the following conditions:
o MCL for a primary contaminant has been exceeded,
o granting of an exemption or variance from a MCL,
o failure to comply with required monitoring program
or with requirements of exemption or variance.
The notice should be included with the first set of water
bills after the failure and should be repeated every three months
until the situation is corrected. Notices should be written in a
manner to assure that the public is well informed.
If a primary contaminant MCL is exceeded, a notice must also
be published for three consecutive days in a newspaper of general
circulation within 14 days. In addition, a copy of the notice
- � should be supplied to the radio and television stations serving
i the area within 7 days.
The following water quality monitoring records should be
-� kept and maintained for the specified period of time:
o Bacteriological tests - results of all analyses ( 5 years)
o Chemical analyses - results of all analyses ( 10 years)
o Documentation of action taken to correct violations of
J drinking water regulations ( 3 years)
J o Public notice information and documentation ( 3 years)
} r
J CROSS CONNECTIONS CONTROL
Washington State regulations place the primary responsibility
for control of cross-connections with the water purveyor (City) .
r�
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The City may be held legally liable for any problems which may
arise due to an unprotected cross connection.
The following is a list of recommendations which should be
implemented or continued to reduce the possibility of cross -
connection contamination.
1 . A Cross Connection Control Specialist (CCS ) should be
delegated the responsibility and authority to organize
and carry out the cross connection control program. He
should be instructed as to the causes and hazards of
unprotected cross connections.
2. All existing facilities, where cross connections are
suspected, should be listed on a priority basis and
inspected.
3. Provisions should be made to route all applications for
new services or for enlarging services through the
CCS.
4. All new construction should be inspected for possible
cross connections. If possible, plans should be
reviewed before construction.
5. A list of backflow devices approved by the Department
of Social and Health Services should be made available
to each water user required to provide backflow protection.
6. A list of certified testers should be made available to
water users who are required to provide backflow
protection devices which require annual inspection or
testing .
98
7. Adequate records, including date of inspection; results
of inspection; recommended protection; list of all
reduced pressure principle backflow devices (RPBD) ,
double check valve assemblies (DCVA) and air gaps in
the system; test and maintenance reports; and all
correspondence between the City, DSHS, and the customer
should be kept and filed for reference.
8. A program should be established to notify the customer
as to the date when his backflow device is to be
tested. (Most regulations require a minimum of once
each year. ) After installation, a device should be
tested and approved before it is accepted by the
City.
If an immediate hazard to health is caused by the cross
connection, water service to the premises should be discontinued
until the cross connection has been corrected.
Failure of the customer to cooperate in the installation,
fmaintenance, testing or inspection of backflow prevention devices
is grounds for the termination of water service to the premises
or the requirement of an air gap separation. Authority to
terminate the water service is included in the State regulations
listed at the first of this chapter.
EMERGENCY RESPONSE
All water supply systems are subject to damage and interuption
from unusual, emergency events. The degree of damage and the
99
This section presents a discussion of the vulnerability of
the Kent system and outlines a general program for responding to
a variety of emergency conditions. To establish an effective
emergency program, more detailed schedules and assignments must
be developed by water department personnel within the outline
presented here. Every employee should be fully aware of their
responsibilities in the event of emergency.
Vulnerability
An overall assessment of system vulnerability indicates that
existing and near-term proposed projects constitute a generally
reliable system. With completion of the Tukwila intertie and the
new East Hill well, over 12 mgd can be delivered to the city.
In the event of an extended failure small emergency supplies
could be obtained from connections with Water District 75 and the
City of Renton. No emergency power is available to Pump Stations
#3 and #4 making the West Hill ( 529 feet) service level vulnerable
to extended power outages although construction of the proposed 1
million gallon tank at 38th and Military Road will provide sufficient
reliability. The East Hill levels are somewhat vulnerable to
excessive drawdown in the James Street tank by the Valley level
although the new 2-3 mgd East Hill well will alleviate this problem.
Public Notifications
Many of the emergency plans which follow call for notification
of the public of emergency conditions and of required demand
curtailment measures. Sample announcements are presented below
100
in increasing order of severity. The City should contact newspapers
and several local radio and television stations who broadcast in
the service area and make prior arrangements concerning emergency
announcements.
SAMPLE I
For Immediate Release
The City of Kent is experiencing unusually high water demand
making it difficult to maintain adequate reservoir reserves.
Residents of the City are requested to reduce water consumption
and to avoid wasting water wherever possible. It will be particularly
helpful , if homeowners will make every effort to reduce lawn
} irrigation. The problem is expected to be temporary in nature,
� 3
and a public announcement will be made when normal water consumption
�.�
can be resumed.
1 SAMPLE II
For Immediate Release
r The City of Kent has experienced a major loss of its production
Jcapacity. The City' s customers are directed to stop all irrigation
and to make every effort to conserve valuable water. The City is
doing everything possible to correct the situation, and will make
a public announcement as soon as the problem has been rectified.
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SAMPLE III
For Immediate Release
This is a Community Emergency Announcement. The City of
Kent has experienced a major loss of its water production capacity
and therefore, is unable to maintain normal water deliveries. It
is mandatory that all irrigation, industrial and commercial use
be discontinued. Water must be conserved for sanitary and
potable use only. Your cooperation is urgently requested. The
City is doing everything possible to restore the water system to
normal operations. You will be notified of any change in the
situation. Note: repeat of above message.
SAMPLE IV
For Immediate Release
The City of Kent has experienced a total loss of its water
production capacity; as a result, the water mains have been shut
off and normal water deliveries have been discontinued. The City
has made arrangements to deliver water by tank truck to residential
areas for potable and sanitary uses only. The following is a
schedule of tank truck deliveries and locations:
(CITE LOCATIONS )
When picking water up at the tank truck locations, please
bring your own clean containers. The City is doing everything
possible to resume normal water service and will notify you as
soon as water service has been restored.
102
State law, WAC 248-54-750 Reporting and Public Notification,
clearly outlines the District' s responsibilities for both oral
and written communication with water users in situations which
may be caused by emergencies. All staff with authority for
public announcements should be familiar with these regulations.
In addition to public announcements, communication with
emergency services is vital. Important phone numbers are included
on the following page and should be posted at all phones.
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1
CITY OF KENT
WATER DEPARTMENT
EMERGENCY PHONE NUMBERS
Kent Water Shops. 872-3395
City Switchboard. 872-3300 (After Hours )
Police Department. 852-2121
Fire Department. 852-2121
Electric Company:
Puget Sound Power and Light 824-6200
Telephone Company:
Pacific Northwest Bell 611
Emergency Pump Service:
Emergency Equipment Rental:
Emergency Chlorine Supplies:
Ambulance Service:
Water Department Superintendent:
Stan J. Boden - Home
Public Works Director:
Office
Home
104
Emergency Response Plans
This section covers recommended actions to specific emergencies.
These are not all inclusive possible actions and improvements
based on experience should be added continually. The first
section are those reactions common to .all such situations. After
1 that each situation is discussed.
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EMERGENCY RESPONSE PLAN
CITY OF KENT
PREPARATION COMMON TO ALL EMERGENCIES
Personnel
1 . Advise personnel to arrange for safety of families in
advance.
2. Prepare emergency schedule and brief personnel.
3. Put all personnel on emergency status.
4. Strategically locate and station crews.
Facilities
On a scheduled basis check the following:
1 . Automotive, auxiliary electric power and pumping
units.
a. Fuel
b. Test emergency power/battery operated lights.
C. Check vehicles for proper operation.
2. Emergency communication equipment for readiness.
3 . Sufficient emergency rations, water, clothing and
bedding on station for 48 hours.
4. Secure equipment and supplies in exposed areas. Secure
buildings, install storm shutters if available.
Materials
1 . Review repair materials for possible local purchase of
items on short supply.
2. Arrange with local suppliers for access to stored
chemicals, tools, repair parts, etc. which may be
required immediately after the disaster.
3. Determine need to relocate certain materials to outlying
sites.
106
EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Major Fire
Assumed Emergency Scenario: Multiple alarm blaze at major commercial establish-
ment, during weekend of peak summer demand period.
System Component and Effects Prevention Recommendations
1 . Reservoirs - Heavy demand will 1 . At first communication of fire
cause drop in water level. demand, check reservoir levels.
Start well if not already
automatically started.
2. Pumps - Reduction of reservoir 1.. Maintain all pumps, and motors
levels should automatically and controls to provide full
activate pumps. supply capacity.
3. Personnel - During off-hours 1. Provide weekend list of staff
and weekends only one who will likely be available for
1 employee is on call. emergency help.
�1
4. Communications - Communicate 1 . Make arrangements with fire and
with fire fighting personnel police officials to relay
to advise on the status of messages by radio.
available pressure during
fire fighting efforts.
�j 5. Power Supply - None 1 . None required.
5. Repair Inventory - Use of 1. Maintain supply of hydrant
hydrants at fire location parts•
may result in damage.
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.d
EMERGENCY RESPONSE PLAN
CITY OF KENT
T'L'PE OF EMERGENCY: Earthquake
Assumed Emergency Scenario: Intensity of 9 on the Modified Mercalli Scale.
Considerable damage and partial collapse of even specially designed buildings.
Displacement from foundations. Ground cracks, underground pipes broken.
Power out. Wells disrupted.
System Component and Effects Correction Recommendations
1 . Mains - Multiple breaks. Fire 1 . Have adequate supply of repair
fighting demand also causing fittings and know locations of
high flows. other supplies, such as supply
distributors.
2. Have detailed system maps in all
vehicles so staff can locate
valves quickly for isolation of
breaks. Have valve wrench in
each vehicle.
3. Loop system as much as is
practical to avoid vulnerability
of single feeders.
4. Prepare action plan to indicate
priority of actions to be
taken.
2. Reservoirs - Some damage likely. 1 . Have plan for rapid inspection
Fire fighting demand may cause of tanks after disaster and
rapid drawdown. isolate from system if damaged
beyond use.
2. Have levels transmitted by radio
to headquarters if necessary so
fire department can be informed.
3. Pumps and Wells - Well pump and 1 . Have plan for rapid inspection
power failure out due to casing of all pumping facilities,
displacement. All electrical starting with emergency well
drives without power. to ensure start of the diesel
engines. Isolate failed units.
2. Call power company or radio to
inform them of power needs and
condition of feed lines to
well.
108
TYPE OF EMERGENCY: Earthquake
System Component and Effects Correction Recommendations
4. Personnel - Mobile units iso- 1. Make all personnel knowledgeable
lated from headquarters by of their duties in the event of
road damage. Coping with a disaster.
personal disaster effects.
2. Cover the topic of disaster aid
in interlocal agreements with
neighboring water suppliers.
3. Have clear lines of authority
pre-established.
5. Communications - Telephone 1 . Maintain mobile radios and train
system severely crippled and all personnel in their use. Use
overloaded. Telemetry out. mobile units to relay informa-
tion until phone service restored.
2. Obtain formal recognition from
phone company on need for
emergency service priority.
Obtain phone number of local
commercial radio stations to
have public service announce-
ments broadcast.
6. Power Supply - Supply line down. 1. Establish priority status with
Most power interrupted. power company.
2. Inform power company of disaster
status via mobile units.
3. Maintain available status of
diesel backup at pump station
and emergency well.
7. Repair Inventory - High demand 1. Maintain supply of repair
for repair fittings and replace- fittings and extra pipe consis-
ment pipe. High demand for tent with the various diameters
chlorine to disinfect system due of pipe and frequency of pipe
' to breakage repair and likely-
material used.
hood of broken sewers. 2. Maintain supply 1 of powdered
sodium hypochlorite consistent
with the manufacturer's storage
recommendations.
3. Be aware of suppliers with
inventories, such as pool supply
firms for chlorine.
109
EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Chlorine Gas Leakage
Assumed Emergency Scenario: Leakage or rupture of chlorine gas cylinder.
System Component and Effects Correction Recommendations
1 . Mains - No effect. 1 . None required.
2. Reservoirs - No effect. 1. None required.
3. Source - Gas fills rooms 1. Isolate gas contaminated area
where chlorine is stored and any and ventilate to atmosphere.
other connected space, espe-
cially low lying areas. Severe 2. Install and maintain chlorine
corrosion of all metal in gas detectors and alarms.
contact with the gas.
3. Isolate gas storage area from
all electrical and mechanical
equipment.
4. Inventory for damage after area
is safe to enter.
4. Personnel - Extreme danger to 1 . Train all personnel in chlorine
life from gas. safety practices.
2. Make approved breathing devices
readily available and have staff
trained in their use.
5. Communications - Police and fire 1 . Use mobile radio units.
departments should be informed.
6. Power Supply - No effects. 1 . None required.
7. Repair Inventory - Need for 1 . Maintain breathing units in
approved breathing apparatus. serviceable condition. Period-
ically check air supply.
110
EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Mechanical Failure of Pumping Equipment
Assumed Emergency Scenario: Unanticipated sudden failure of a well pump
during periods of high demand.
System Component and Effects Correction Recommendations
1 . Mains - No effect. 1 . None required.
2. Reservoirs - Loss of supply 1. Make arrangements for appropri-
during peak demand will drawdown ate repair.
reservoir levels.
3. Pump Stations - Auxilliary pumps 1 . Have list showing pump supplier
should start automatically. or manufacturer's representative
Pump stations #3 and #4 out of for each pump. Also, local Pump
service. and motor repair shops.
2. Monitor reservoir levels closely.
� 4. Source - Wells put out of 1 . Monitor reservoir levels closely.
operation, infiltration galleries
still operable.
5. Personnel - Necessity for repair 1 . Develop clear job descriptions
will cause some personnel to which indicate who should be
1F� ignore routine activities. involved in actual repair, who
should be involved in substitut-
ing for personnel involved in
repair, and who will make what
decisions.
6. Communications - Reduced supply 1. Have list of local commercial
of water may require reduced broadcasting companies and have
consumption. them announce conservation
Imethods if appropriate.
.J 7. Power Supply - No effects. 1 . None required.
8. Repair Inventory - Pump may fail 1 . Maintain supply of field replace-
due to small part such as shaft able parts for each pump.
cnupl ing.
2. Have a list showing phone number
and address of local parts
suppliers.
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EMERGENCY RESPONSE PLAN
CITY OF KENT
W E OF EMERGENCY: Bomb Threats
Assumed Emergency Scenario: fine City receives a call containing a threat
of sabatoge by explosives, probably by phone call or by letter.
System Component and Effects Prevention Recommendations
1 . Mains - No immediate problem as 1. None required.
these would be unlikely targets.
2. Reservoirs - Likely target. 1 . Attempt to get caller to reveal
the location of the bomb.
2. Immediately notify police and
fire departments with location
of target or if not }mown, all
possible targets.
3. Make arrangements to start
draining the target reservoir if
at all possible by wasting
water through hydrants.
3. Source - Likely target. 1 . Same as Step 1 for Reservoirs.
2. Same as Step 2 for Reservoirs.
3. Procede to shut down targeted
facilities and isolate from the
system.
4. Make special note to inform
police and fire departments
about the location of chlorine
gas at facilities.
4. Personnel - Office will receive 1 . Instruct all staff that might
call, field crew will react. handle calls on how to react to
caller with bomb threat. Keep a
copy of the form shown here or
something comparable near the
main switchboard and at fire
department switchboard.
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TYPE OF EMERGENCY: Bomb Threats
System Component and Effects Prevention Recommendations
5. Communications - Clear, concise 1. Ensure training of all staff in
communication will be required reaction to threatening calls.
to ensure timely response. Consider the possibility of an
unannounced drill on some
periodic basis. Be sure to
coordinate with police and fire
units.
6. Power Supply - Likely to be 1. No action required other than
affected only peripherally to those already outlined.
other facilities.
7. Repair Inventory - Unlikely 1 . Well stocked inventory will
target. facilitate repairs.
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REPORTING BOMB THREATS
Responsibility Action
Person receiving i. Attempt to retain the caller "Long enough to obtain
call all pertinent information such as on a bomb threat,
where it is located, what type of bomb it is, and
when its set to go off.
2. Listen carefully to the exact words of the message
so that you can repeat the information clearly and
accurately.
3. Listen for background noises, voice accent, word
pronunciation, voice pitch (high or low) , male or
female voice, and if it sounded like a child or
adult.
4. Try to signal another person near you to pick up the
same telephone line and listen in.
5. Prepare a list of the following information:
- Date and Time of Call
- Type of Bomb
- Location of Bomb
- Description of Bomb
- What caller actually said
- Sex of caller
- Estimated age of caller
- Type of voice (soft, loud, whisper, normal,
drunk)
- Background noises heard, if any
- Your name and location
6. Report the threat to the Police Department and the
Director of Public Works.
Superintendent 7. Notify employees to search their areas.
8. Notify local law enforcement agency having juris-
diction.
Employees 9. Search their own work area for suspicious objects or
packages as follows:
a. Desks
b. Wastebaskets
C. File Cabinets
d. Supply Room
e. Closets
f. Ashtray Receptacles
g. Locked Doors
h. Underside of Horizontal Surfaces
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Responsibility Action
Employees 10. Turn off electric machinery or other noise making
equipment.
11 . Notify immediate Supervisor of the results of your
search.
12. Search nonwork areas in your assigned area including:
a. Restrooms
r-� b. Conference Rooms
C. Coffee Shops
d. Store Rooms
e. Hallways, Stairways and Lobbies
" 1 (See Exhibit 1 for Assignments)
II 13. If results of search are negative, proceeds as
follows:
4
a. Notify immediate Supervisors and remain calm
and in their work areas.
71
Immediate b. Notify Supervisors Office by telephone or in
Supervisor person of negative results.
14. If a suspicious object of package is discolsed at
any time - whether or not a bomb threat call has
been received, proceeds as follows:
L� Employees a. Do not move touch or in anyway disturb the
object or package.
b. Immediately notify your immediate Supervisors
or next available Supervisor, if not available.
Immediate C. Clear all persons from the immediate area and
Supervisor notify the office of location and description of
the suspicious object or package.
Supervisor 15. Evaluates available information and makes a decision
on evacuation.
16. Notifies employees of evacuation or all clear.
Employees 17. Employees when directed to evacuate, leave building.
18. Take coats, jackets, purses and briefcases with them
when they leave the work area.
19. Lock Cash Drawers and other valuable items.
'l
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EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Major Power Outage
Assumed Emergency Scenario: Entire city loses power during high power c
demand period (cold weather). `
System Component and Effects Prevention Recommendations
1 . Mains - No immediate effect. 1 . None required.
2. Reservoirs - Extended outage 1 . Monitor levels closely. Use
will cause reservoir drawdown mobile radios if telephone system
in high service areas. is affected.
3. Source - Wells out of service 1 . No action required as pumps will
gravity Supply continued. automatically restart with
restoration of power.
4. Pump Stations - Pump Stations 1. Monitor West Hill reservoir levels
#3 & #4 out of service. #5 carefully; monitor James St. tank
provides water to East Hill level to insure adequate supply for
automatically East Hill area. Close valve from
James St. tank to Valley system if
necessary.
5. Personnel - Routine mainte- 1 . All personnel should at a
nance will be ignored while minimum be on standby status to
staff monitors system condi- assist with emergency lighting
tion. and power distribution.
6. Communications - Telephone 1 . Maintain all mobile radio units
circuits operable, but over- in excellent condition.
crowded.
2. Consider requesting help from
police or fire departments in
notifying key personnel if
telephones and radio are inoper-
able.
7. Power Supply - Power off. 1. Check status of diesel unit at
Emergency power required. Pump Station #5. Be ready to
respond to demand.
2. After power is restored, inven-
tory all electrical equipment and
check for return of normal
operations.
8. Repair Inventory Demand for i . Stock and maintain supply of
lantern batteries. portable lights.
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EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Accident or Illness to Personnel
Assumed Emergency Scenario: A member of the City's staff becomes
serious ill or suffers an accident resulting in inability to work.
Note: All accidents occuring on the job, no matter how minor, must be
reported to the appropriate supervisor.
System Component and Effects Prevention Recommendations
1 . Mains - No immediate effect. 1. Provide more than one staff
Routine maintenance may be member with knowledge of an
delayed. access to necessary maintenance
information.
2. Reservoirs - No immediate 1 . Same as Mains.
effect. Routine maintenance may
be delayed.
3. Source & Pump Stations - No 1. Same as Mains.
immediate effect. Routine main-
tenance may be delayed.
4. Personnel - Staff will possibly 1 . In the event of any serious
be faced with situation requir- accident, immediately call or
ing first aid. Long term effect radio for a doctor or ambulence.
will be short-handed staff. Give name, location and brief
i description of incident.
2. Have all staff trained in first
aid and cardiopulmanary recessi-
tation (CPR).
3. Have chain of command clearly
displayed and frequently updated.
4. Have at least two staff members
1 trained in each critical main-
tenance function.
5. Communications - No immediate or 1 . Maintain all mobile radios in
long range effect. May be good condition.
needed in the event of an
accident.
6. Power Supply - No effect. 1 . None Required.
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TYPE OF EMERGENCY: Accident or Illness to Personnel
System Component and Effects Prevention Recommendations
7. Repair Inventory - No irmediate 1 . Provide more than one staff
effect. Routine restocking may member with knowledge of and
be delayed. access to necessary information. -
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EMERGENCY RESPONSE PLAN
CITY OF KENT
TYPE OF EMERGENCY: Subzero Weather
Assumed Emergency Scenario: Extended freezing weather has promoted deep
frost penetration in the soil, especially under cleared streets. Local
service connection lines are freezing, especially on isolated runs. Water
demand high due to tap running. Condition will be similar throughout
State affecting all neighboring water suppliers.
System Component and Effects Prevention Recommendations
1 . Mains - Effects are unlikely. 1 . Fill meter boxes with insulating
Routine maintenance will likely material to resist pipe freezing.
be disrupted by repair of frozen
service lines. 2. Areas of widespread problems
should be documented and examined
for preventative measures such
as deeper mains, insulated meter
boxes, special customer notifica-
tion of problem and solutions
and so forth.
2. Reservoirs - No immediate 1. Monitor levels closely.
effect. Demand may result in
excessive drawdown.
3. Source - No immediate problem. 1 . Check condition of space heaters
High demand will cause longer prior to winter cold weather
than normal operation. period.
Power outage or space heater
failure could threaten source 2. Schedule normal maintenance
piping. prior to periods of possible
cold weather.
3. Maintain sources of emergency
space heating at the District.
Rentals cannot be relied on
because of the heavy demand on
heaters throughout the region.
4. Personnel - Routine maintenance 1 . Make staff aware of proper cold
will be slowed due to cold weather work clothing and
working conditions and staff symptoms of frostbite.
needed to thaw out service
lines. 2. Establish system of priority for
thawing service lines so that
field staff will not have to make
decisions without guidance.
119
TYPE OF EMERGENCY: Subzero Weather
System Component and Effects Prevention Recommendations
5. Communications - No iiiTnediate 1 . NIo action required.
effect.
6. Power Supply - Outages due to 1. Inform power company immediately
overloading or power pole of any supply problems.
accident likely.
2. Check status of all emergency
power and heat units.
7. Repair Inventory - Repairs to 1. Check items used in frozen line
frozen service lines and emer- repair, fuels and equipment
gency heating will require for emergency power prior to
adequate inventories. cold weather season. During
cold weather, suppliers will
likely be out of stock.
120
CHAPTER XI
DEVELOPER CRITERIA AND STANDARDS
The following description of minimum criteria and standards
is recommended- for adoption by the City of Kent as a requirement
to be met by developers.
A. MATERIALS
A. 1 Standards
Pipe, fittings, valves and fire hydrants shall conform
to the latest standards issued by the AWWA, and be
acceptable to the City Engineer. The City accepts only
Cast Iron or Ductile Iron pipe Class 52.
A.2 Joints
Ll Packing and jointing materials used in the joints of
pipe shall meet the standards of the AWWA and the
City Engineer. Pipe having mechanical joints or
slip-on joints with rubber gaskets is preferred.
B. WATER MAIN DESIGN
t The normal working pressure in the distribution system
J should be approximately 60 psi and not less than 35 psi .
B. 1 Pressure
All water mains, including those not designed to
provide fire protection, shall be sized after a hydrau-
lic analysis based on flow demands and pressure
requirements . The system shall be designed to maintain
a minimum pressure of 20 psi at ground level at all
�J points in the distribution system under all conditions
{, of flow.
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i
B. 2 Diameter
The minimum size off water main for providing fire
protection and serving fire hydrants shall be six inch
diameter for circulating mains and eight inch diameter
for dean-end mains. Larger size mains will be required
if necessary to allow the withdrawal of the required
fire flow while maintaining the minimum residual
pressure specified in Section B. 1 .
B.3 Fire Protection
When fire protection is to be provided, system design
should be such that fire flows and facilities are in
accordance with the requirements of the Washington
Surveying and Rating Bureau.
BA Small Mains
Any departure from minimum requirements shall be
justified by hydraulic analysis and future water use,
and can be considered only in special circumstances.
B. 5 Hydrants
Water mains not designed to carry fire-flows shall not
have fire hydrants connected to them.
B.6 Dead Ends
Dead ends shall be minimized by looping of all mains
whenever practical.
B.7 Flushing
Where dead-end mains occur they shall be provided with
a fire hydrant if flow and pressure are sufficient, or
with an approved flushing hydrant or blow-off for
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flushing purposes. No flushing device shall be directly
connected to any sewer.
C. VALVES
Sufficient valves shall be provided on water mains so that
inconvenience and sanitary hazards will be minimized during
repairs. Valves should be located at not more than 500 foot
intervals in commercial districts and at not more than one
block or 800 foot intervals in other districts.
D. HYDRANTS
D. 1 Location and Spacing
Hydrants should be provided at each street intersection
and at intermediate points between intersections as
recommended by the Washington Surveying and Rating
Bureau. Maximum hydrant spacing shall be 600 feet in
llsingle-family zoned areas and 300 feet in commercial,
_J industrial and apartment areas. Duplexes, churches and
schools shall be considered as commercial.
D. 2 Valves and Nozzles
Fire hydrants should have a bottom valve size of at
�J least five inches, one 4-1/2 inch pumper nozzle and two
2-1/2 inch nozzles.
D.3 Hydrant Leads
The hydrant lead shall be a minimum of six inches in
diameter. Auxiliary valves shall be installed in all
hydrant leads.
r�
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rJ
D A Drainage
Hydrant drains should be plugged. When the drains are
plugged the barrels should be pumped dry during freezing
weather. Where hydrant drains are not plugged, a
gravel pocket or dry well shall be provided unless the
natural soils will provide adequate drainage. Hydrant
drains shall not be connected to or located within 10
feet of sanitary sewers or storm drains.
E. AIR RELIEF VALVES; VALVE, METER AND BLOW-OFF CHAMBERS
E. 1 Air Relief Valves
At high points in water mains where air can accumulate
provisions shall be made to remove the air by means of
hydrants or air relief valves. Automatic air-relief
valves shall not be used in situations where flooding
of the manhole or chamber may occur.
E. 2 Air Relief Valve Piping
The open end of an air relief pipe from automatic
valves shall be extended to at least one foot above
grade and provided with a screened, downward-facing
elbow. The pipe from a manually operated valve should
be extended to the top of the pit.
E.3 Chamber Drainage
Chambers, pits or manholes containing valves, blow-offs,
meters, or other such appurtenances to a distribution
system, shall not be connected directly to any storm
drain or sanitary sewer, nor shall blow-offs or air
relief valves be connected directly to any sewer. Such
124
chambers or pits shall be drained to the surface of the
ground where they are not subject to flooding by
surface water, or to absorption pits underground.
F. INSTALLATION OF MAINS
F. 1 Standards
Specifications shall incorporate the provisions of the
AWWA standards and/or manufacturer' s recommended
installation procedures.
F. 2 Bedding
A continuous and uniform bedding shall be provided in
the trench for all buried pipe. Backfill material
shall be tamped in layers around the pipe and to a
sufficient height above the pipe to adequately support
and protect the pipe. Stones found in the trench shall
be removed for a depth of at least six inches below the
bottom of the pipe.
F.3 Cover
All water mains shall be covered with sufficient earth
�J or other insulation to prevent freezing.
_J FA Blocking
All tees, bends, plugs and hydrants shall be provided
with reaction blocking, tie rods or joints designed to
prevent movement.
i F.5 Pressure and Leakage Testing
The installed pipe shall be pressure tested and leakage
' tested in accordance with AWWA Standard C600.
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F.6 Disinfection
All new, cleaned or repaired water mains shall be
disinfected in accordance with AWWA Standard C601 . The
specifications shall include detailed procedures
for the adequate flushing, disinfection, and microbio-
logical testing of all water mains.
G. SEPARATION OF WATER MAINS AND SEWERS
G. 1 General
The following factors should be considered in providing
adequate separation:
a. materials and type of joints for water and sewer
pipes,
b. soil conditions,
C. service and branch connections into the water main
and sewer line,
d. compensation variations in the horizontal and
vertical separations,
e. space for repair and alterations of water and
sewer pipes,
f. off-setting of pipes around manholes.
G.2 Parallel Installation
Water mains shall be laid at least 10 feet horizontally
from any existing or proposed sewer. The distance
shall be measured edge to edge. In cases where it
is not practical to maintain a ten foot separation, the
126
City Engineer may allow deviation on a case-by-
case basis, if supported by data from the design
engineer. Such deviation may allow installation of the
water main closer to a sewer, provided that the water
main is laid in a separate trench or on an undisturbed
earth shelf located on one side of the sewer at such an
elevation that the bottom of the water main is at least
18 inches above the top of the sewer.
G.3 Crossings
Water mains crossing sewers shall be laid to provide a
minimum vertical distance of 18 inches between the
outside of the water main and the outside of the sewer.
This shall be the case where the water main is either
above or below the sewer. At crossings, one full
length of water pipe shall be located so both joints
will be as far from the sewer as possible. Special
structural support for the water and sewer pipes may be
required.
GA Exception
_. The City Engineer must specifically approve any variance
from the requirements of Sections G.2 and G.3 when it
is impossible to obtain the specified separation
distances.
G. 5 Force Mains
JThere shall be at least a 10 foot horizontal separation
Ibetween water mains and sanitary sewer force mains.
' There shall be an 18 inch vertical separation at
crossings as required in Section G. 3 .
127
G.6 Sewer Manholes
No water pipe shall pass through or come in contact -
with any part of a sewer manhole.
H. SURFACE WATER CROSSINGS
Surface water crossings, whether over or under water,
present special problems. The City Engineer should be
consulted before final plans are prepared.
H. 1 Above-Water Crossings
The pipe shall be adequately supported and anchored,
protected from damage and freezing, and accessible for
repair or replacement.
H. 2 Underwater Crossings
A minimum cover of two feet shall be provided over the
pipe. When crossing water courses which are greater
than 15 feet in width, the following shall be provided:
a. the pipe shall be of special construction, having
flexible watertight joints,
b. valves shall be provided at both ends of water
crossings so that the section can be isolated for
testing or repair; the valves shall be easily
accessible, and not subject to flooding; and the
valve closest to the supply source shall be in a
manhole;
C. permanent taps shall be made on each side of the
valve within the manhole to allow insertion of a
small meter for testing to determine leakage and
for sampling purposes.
128
I
I . CROSS CONNECTIONS AND INTERCONNECTIONS
I. 1 Cross Connections
ection between the distribution
There shall be no conn
system and any pipes, pumps, hydrants, or tanks whereby
unsafe water or other contaminating materials may
1 be discharged or drawn into the system.
I . 2 Cooling Water
condensate nor cooling water from engine
Neither steam
returned
jackets or other heat exchange devices shall be
to the potable water supply.
I.3 Interconnections
The approval of the City Engineer shall be obtained for
lies.
interconnections between potable water supp
J. WATER SERVICES AND PLUMBING
J. 1 Plumbing
Water services and plumbing shall conform to relevant
Washington State plumbing codes and City of Kent.
J. 2 Booster Pumps
Individual home booster pumps shall not be considered
or required for any indi
vidual service from the public
water supply mains.
K. SERVICE METERS
` Each service connection should be individually metered.
129
1