HomeMy WebLinkAboutSunrise Lake Water Supply and Hydroelectric Project 1998SUNRISE LAKE WATER SUPPLY
AND HYDROELECT~I~ PROJ~CT
·~ • 4 ' • .: ' • • ' " , __ ' / ••
'\ .·· . ' ' -" -·
ADDENDUM TO __
' FEASIBIUTYSTUDY REPORJ __ .··;· .. ·_
ExPANSION OF THE WRANGELLIS~..na
-WATERSUPPLYSYSTEM
City of Wrangell, Ala
September 1998
R'WfitCK
September 1, 1998
Mr. Scott W. Seabury
City Manager
RIWillECK
City of Wrangell
205 Brueger
P. 0. Box531
Wrangell, AK 99929
Subject: Sunrise Lake Water Supply and Hydroelecbic Project
Addendum to Feasibility Study Report
Wrangell Island Water Supply System
Dear Mr. Seabury:
In general accordance with the terms of our agreement, we respectfully submit herewith a
Addendum to the Sunrise Lake Water Supply and Hydroelectric Project Feasibility Study
Report (Feasibility Study), Wrangell Island Water Supply System, for the City's review and
comment.
The scope of the Feasibility Study that was prepared for the City in early 1998 was confined
to the study of water supply and hydroelectric facilities on Woronkofski Island and the
water supply line across Zimovia Strait to Wrangell Island. Following the completion of this
Feasibility Study, the City recognized the need for the Feasibility Study to take into
consideration the City's water supply system on Wrangell Island in the overall project
planning. Preparation of this Addendum to the Feasibility Study was authorized to address
this need.
It is our sincere hope that the City finds that this Addendum provides the necessary
information with which to make informed decisions regarding their water supply system
on Wrangell Island, as well as with respect to the Sunrise Lake Water Supply and
Hydroelectric project
A summary of our investigation, principal findings, conclusions and recommendations is
presented in the Executive Summary of the report.
If there are any questions regarding this Addendum, please do not hesitate to contact me.
Sincerely,
R. W. ~E~:·¢1 St~.E. ·
Project Manager
Enclosure
RA.K/rhrn
c: Messrs. Todd Glass and Eric Redman, Heller Ehrman White & McAuliffe
Xl10222.353
1001 Fourth Avenue, Suite 2500 Seattle. WA 98154-1004 Phone (206) 695-4700 Fax (206) 695-4701 <V
ENGINEER'S CERTIFICATE
SUNRISE LAKE WATER SUPPLY AND
HYDROELECTRIC PROJECT
The technical material and data contained in this report were prepared under the
supervision and direction of the undersigned whose seal as Professional
Engineer is affixed below:
-~....--~~",, ~t\~··.. ' ,.,q,~. • .....
'·: 49tH * . •1. ' .......... ·.1.& ~ . . . . . . . . . . .
1\1REED A. IIEU.Y ~· ·~ •• No. aD... J' .. . . . ., ,,,~;,
X11~353 8r.UV98 fi'W'~ECK
LETTER OF TRANSMITIAL
ENGINEER'S CERTIFICATE
TABLE OF CONTENTS
CITY OF WRANGELL
SUNRISE LAKE WATER SUPPLY AND
HYDROELECTRIC PROJECT
TABLE OF CONTENTS
EXECUTIVE SUMMARY ....................................................................................... 1
TREATMENT FACILITIES .................................................................................. 1
QUANTITY .................................................................................•..................... 1
MARINE PIPELINE ALIGNMENT ...................................................................... 2
BOOSTER PUMP STATION .............................................................................. 2
TRANSMISSION MAIN .................................................................................... 3
FUTURE WATER SUPPLY SYSTEM IMPROVEMENTS ....................................... 3
Water Treatment Plant ................................................................................... 3
Water System Improvements ......................................................................... 4
SECTION 1 INTRODUCTION ....•................................................•..............•....• 1
BACKGROUND ............................................................................................... 1
PURPOSE AND SCOPE .................................................................................... 1
SECTION 2 IDENTIFICATION AND EVALUATION OF ALTERNATIVES. ••.••.•.• 1
GENERAL ......................................................................................................... 1
TREATMENT CONSIDERATIONS ..................................................................... 1
WATER SUPPLY CONSIDERATIONS ................................................................ 3
Quantity ........................................................................................................ 3
Marine Pipeline Alignment ............................................................................ 3
Hydraulic ...................................................................................................... 5
BOOSTER PUMP STATION LOCATION ALTERNATIVES .................................. 5
Booster Pump Station Design ........................................................................ 6
TRANSMISSION MAIN ALIGNMENT ALTERNATIVES ...................................... 6
EVALUATION OF WATER CONVEYANCE ALTERNATIVES ............................... 7
Capital Costs ................................................................................................. 7
Engineering and Construction Issues ........................................................... 14
ALTERNATIVEs 1Aand 1B ....................................................................... 14
ALTERNATIVE 2 ....................................................................................... 14
Permitting!Environmental Issues .................................................................. 14
X110222.35 8128198 R'vV'~ECK
TABLE OF CONTENTS
ALTERNATIVEs 1A and 1 B ...................................................................... 14
i\LTERNATIVE 2 ...................................................................................... 15
Other Issues ................................................................................................ 15
ALTERNATIVEs 1A and 1 B ...................................................................... 15
Recommended Transmission Main Alternative ............................................ 16
SECTION 3 FUTURE WATER SUPPLY SYSTEM IMPROVEMENTS ................... 1
WATER TREATMENT PLANT EXPANSION REQUIREMENTS ........................... 1
WATER SYSTEM IMPROVEMENTS .................................................................. 1
SECTION 4 ESTIMATED CONSTRUCTION COST AND SCHEDULE. ............. 1
GENERAL ......................................................................................................... 1
BASIS OF COSTS ............................................................................................. 1
Direct Construction Cost. .............................................................................. 1
Contingencies ............................................................................................... 1
Engineering and Owner Administration ........................................................ 2
Total Construction Cost ................................................................................. 2
Escalation ...................................................................................................... 2
Interest During Construction ......................................................................... 2
Total Investment Cost .................................................................................... 2
CONSTRUCTION COST ESTIMATE ................................................................. 2
DESIGN AND CONSTRUCTION SCHEDULE .................................................. 4
General ......................................................................................................... 4
Design and Contract Documents .................................................................. 4
Construction ................................................................................................. 5
LIST OF TABLES
TABLE 2-1
TABLE 2-2 CONSTRUCTION COST ESTIMATE-ALTERNATIVE 1A
TABLE 2-3 CONSTRUCTION COST ESTIMATE-ALTERNATIVE 1 B
TABLE 2-4 CONSTRUCTION COST ESTIMATE-ALTERNATIVE 2
TABLE 4-1 CONSTRUCTION COST ESTIMATE SUMMARY
TABLE 4-1 BACKUP CONSTRUCTION COST ESTIMATE PROJECT
ALTERNATIVE WITH 4.0 MW HYDRO UNIT
LIST OF FIGURES
FIGURE 2-1 PENSTOCK/WATER SUPPLY PIPELINE ALIGNMENT
FIGURE 2-2 PROJECT ALTERNATIVES
ti R. W Beck &'28/98 X110222.35
CITY OF WRANGELL
This report has been prepared for the use of the client for the specific purposes identified in the
report. The conclusions, observations and recommendations contained herein attributed to
R. W. Beck, Inc., ("R. W. Beck") constitute the opinions of R. W. Beck. To the extent that
statements, information and opinions provided by the client or others have been used in the
preparation of this report. R. W. Beck has relied upon the same to be accurate, and for which
no assurances are intended and no representations or warranties are made. R. W. Beck makes
no certification and gives no assurances except as explicitly set forth in this report.
Copyright 1998, R. W. Beck, Inc.
All rights reserved.
X110222.35 8128198 R. W Beck iii
EXECUTIVE SUMMARY
The scope of the Feasibility Report for Sunrise Lake Water Supply and Hydroelectric
Project (Feasibility Study) that was prepared for the City of Wrangell in early 1998
was confined to the study of water supply and hydroelectric facilities on
Woronkofski Island and the water supply line across Zimovia Strait to Wrangell
Island. Following completion of the Feasibility Study, the City recognized the
need for the Feasibility Study to include improvements to the water supply
system on Wrangell Island for expanding or replacing the City's current water
supply with one of superior quality and quantity available from Sunrise Lake.
Following is a summary of our findings and recommendations.
TREATMENT FACILITIES
Instead of constructing separate and redundant treabnent facilities on
Woronkofski Island, we recommend that the City's overall water supply system
scheme take full advantage of its new water treabnent and storage facilities on
Wrangell Island. Making use of these facilities makes sense not only because of
the investment in them, but also because of the level of treabnent uncertainties in
both Sunrise Lake's water quality and in the uncertainties of the City's future
economic growth. Using the new treatment facilities will have the following
advantages over a separate treabnent system:
• Reduces both capital and operational treatment costs.
• Allows the City to collect the necessary water quality data from Sunrise Lake
for a possible waiver from filtration.
• Provides the City the time to determine the water supply needs for economic
growth in the community made possible with the Sunrise Lake Project.
• Provides greater system reliability.
QUANTITY
We recommend that the water supply pipeline capacity from Sunrise Lake be
increased from 1.5 MGD to 3.0 MGD. The incremental cost of the water supply
line to double its capacity is approximately 30 percent. Also, increasing the
supply capacity from Sunrise Lake would allow the City to either abandon its
existing source or use it as an emergency backup service. By shifting the City's
entire water source to Sunrise Lake, the City may be able to use their existing
watershed for other benefits, especially since available developable land in the
vicinity of Wrangell is scarce. Therefore, we recommend that the water supply
line from Woronkofski Island be increased to 16-inch (HDPE nominal OD,
14.5 inch ID).
X110222.353 8128/98 H'vV'~ECK
EXECUTIVE SUMMARY
MARINE PIPELINE ALIGNMENT
The Feasibility Study selected the marine pipeline across Zimovia Strait that had
the shallowest alignment and most direct crossing between Woronkofski and
Wrangell islands (Alternative 1). This alignment was selected without
consideration of the ultimate location of use on Wrangell, although the possibility
of providing this water to serve the area south of Wrangell was a consideration.
In order to bring to bring the water north to the water treatment plant, the
supply line will need to be located either along the Zimovia Highway R.O.W or
along the intertidal zone. Because of the recent reconstruction of Zimovia
Highway (1995), it would be difficult to obtain the Department of
Transportation's approval and contend with all the utilities beneath the Highway.
Installing the water supply pipeline in the intertidal zone is more straightfoward
and significantly less costly. The pipeline would run along the shoreline in a
northerly direction for approximately one mile and then move inland at the
north end of Cemetery Point.
Further evaluation of the route on Woronkofski Island led to a change in the
overall route so that the marine line would run directly from the project jetty on
Woronkofski Island to Wrangell Island and then up the coast to Cemetery Point
as shown in Figure 2-1 (Alternative 2). Also, the pipeline diameter of both
alternative routes increased from a 14-inch to a 16-inch nominal diameter to
account for the additional one-mile distance along the intertidal zone to the
booster pump station.
While Alternative 1 was not appreciably less costly than Alternative 2 ($60,000),
this alternative route eliminates potential environmental impacts to several
streams on Woronkofski Island. However, with the additional one-mile length of
HDPE pipe in the intertidal zone, the direct construction cost of this feature
increased by about $360,000 from that indicated in the Feasibility Study.
BOOSTER PUMP STATION
The powerhouse is proposed to be situated at an elevation that maximizes the
power generation potential while still allowing water to be conveyed to Wrangell
Island by gravity. The elevation of the powerhouse has been established at
around elevation 140 feet MSL, while the treatment plant is located at an
elevation of approximately 265 feet MSL. In order to gravity-flow to the water
treatment plant, the powerhouse would have to be situated at an elevation of
approximately 430 feet MSL, which would result in a considerable loss of power
generation potential. Consequently, a booster pump station is needed. For
reasons similar to those for locating the treatment facilities on Wrangell Island, it
is recommended that the booster pump station also be located on Wrangell
Island, in the general vicinity of Cemetery Point. The cost of this booster pump
station is included with the transmission main.
2 R. W Beck 08128/98 X110222.353
EXECUTIVE SUMMARY
TRANSMISSION MAIN
From the terminus of the marine pipeline at Cemetery Point, three potential
routes to the water treatment plant were investigated. One route runs generally
from the cemetery (cemetery just south of the wastewater treatment plant), up
the drainage of the City's reservoirs to the plant (Alternative 1A). This route
requires the construction of an access road. A variation of this route
{Alternative 1B) is without an access road for maintenance. The other route is
northerly along Zimovia Highway to the water treatment plant/reservoirs access
road (Wood Street), then along the access road to the water treatment plant
(Alternative 2). The direct construction costs for Alternatives 1A, 1B and 2,
including the booster pump station, were determined to be approximately
$1.2 million, $0.9 million, and $1.7 million, respectively. Because Alternative 1A
requires the construction of an access road, it has greater environmental impacts
than Alternatives 1B or 2. Provided that subsequent environmental studies
confirm there are no significant adverse impacts which cannot be mitigated, the
anticipated impacts appear minor and can be minimized with appropriate
mitigation measures. Nevertheless, Alternative 1B is the recommended
alternative because of its least cost and minimal environmental impact.
FUTURE WATER SUPPLY SYSTEM IMPROVEMENTS
WATER TREATMENT PLANT
The water treatment plant has a capacity of 1.3 MGD. Sunrise Lake's water
supply pipeline will have a capacity of 3.0 MGD. This means that the water
treatment plant (or portions thereof) will eventually need to be expanded by
1.7 MGD in order to take full advantage of the water supply.
The results of the initial, albeit limited, water quality data have indicated that
Sunrise Lake water is superior to the City's existing water source and, in fact,
could likely be exempted from filtration. However, the level of required
treatment will be unknown until water sampling and testing is performed for a
one-year period per State of Alaska Department of Environmental Conservation
Regulations.
If the water quality meets the Surface Water Treatment Rules (SWTR) and the
City is successful in obtaining a waiver from filtration, expanding the plant's
disinfection system would not require much space. If filtration were required
and if the same means for filtration were used (i.e., low rate, slow sand filtration),
considerably more space would be needed. The water treatment plant site offers
limited space for plant expansion, and it appears doubtful that the existing site
could feasibly be expanded to accommodate this type of filtration process.
Rather, it is considered much more probable that high rate filtration would be
used to expand the filtration capacity of the plant.
X110222.353 8128198 R. W Beck 3
EXECUTIVE SUMMARY
The preliminary construction costs were estimated for these two treatment
alternatives. In the case where filtration is not required and only the capacity of
the disinfection system needs to be expanded, the cost was estimated to be
around $1.7 million. If the capacity of the disinfection system is expanded and
high rate filtration is used to replace the slow sand filtration system completely to
provide 3.0 MGD of capacity, the cost is estimated to be $5.0 million. This
amount was not included in the cost estimate of the selected arrangement
because treatment expansion can be postponed to a later stage. In fact, the
$200,000 chlorination facility (see Feasibility Study) to have been located on
Woronkofski has been eliminated.
WATER SYSTEM IMPROVEMENTS
Because future demands from economic development and growth are
unpredictable at this time, it is recommended that the booster pump station be
sized to meet the current projected demands and match the capacity of the water
treatment plant of 1.3 MGD. Reasonable provisions can be made in the design of
the booster pump station to allow for future expansion to 3.0 MGD. But, until
the demands are truly established/realized and the demands exceed
approximately 80 percent of the capacity of the plant, it is best to provide a
pumping system that matches, more or less, the actual system demands and head
requirements. When additional capacity is required, the pumping system can be
modified, additional and/or larger pumping units can be installed or perhaps
some combination used.
Other water supply system improvements will be needed as economic growth
occurs and the peak day demand increases above 1.3 MGD as well For example,
the capacity of the plant's finished water pumping facilities will have to be
increased and the capacity of the storage facilities will need to be increased in
order to provide the same level of service for meeting demands and fire
protection.
4 R. W Beck 08128/98 X110222.353
BACKGROUND
SECTION 1
INTRODUCTION
In October 1997, the Oty of Wrangell (Oty) commissioned R. W. Beck to evaluate
the feasibility of using Sunrise Lake, which is located on Woronkofski Island, as a
potential water supply and source of hydroelectric power. In general accordance
with a contract dated October 24, 1997, R. W. Beck submitted a feasibility study
titled Sunrise Lake Water Supply and Hydroelectric Project (Feasibility Study) to the
City in January 1998 (revised version submitted in Apri11998). The scope of the
Feasibility Study was confined to water supply and hydroelectric facilities on
Woronkofski Island and a water supply line across Zimovia Strait to Wrangell
Island. The study of potential water supply system connections and
improvements on Wrangell Island was not included as part of this Feasibility
Study.
At the conclusion of the Feasibility Study, the findings were favorable to the City.
The Oty recognized the need for the Feasibility Study to take into consideration
its water supply system on Wrangell Island in the overall project planning. In
March 1998, the City commissioned the preparation of an addendum to the
Feasibility Study to develop conceptual design and construction cost estimates of
water supply system connections and improvements on Wrangell Island.
PURPOSE AND SCOPE
The purpose of this Feasibility Study Addendum is to investigate and assess the
water supply system improvements needed on Wrangell Island for the Sunrise
Lake Project Because it made good sense to use the new water treatment and
storage facilities, this investigation focused on making the most use of these
facilities in the City's overall water supply scheme. The use of these facilities is
prudent due to the level of treatment uncertainties with Sunrise Lake water.. 11
Consequently, the study focused on the conceptual design of a booster pump
station and transmission main that would convey the water from the terminus of
the marine pipeline on Wrangell Island to the City's new water treatment plant.
This study also, at the suggestion of the U.S. Forest Service (USFS) and the Alaska
Department of Fish and Game (ADFG), investigated an alternative marine
pipeline alignment for conveying Sunrise Lake water from Woronkofski Island to
Wrangell Island.
X110222.353 8128198 fi'\V'~ECK
GENERAL
SECTION 2
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
During the course of the study, various water supply system alternatives were
considered in selection, location and design of major Project features in
conveying water from the power plant on Woronkofski Island to Wrangell Island
and for the treatment of the Sunrise Lake water. We first evaluated the need for
additional treatment facilities by reviewing the City's new treatment plant,
currently under construction. Then, we evaluated several alternatives for
conveying the water to the treatment plant. The evaluation of the water
conveyance arrangement examined three components: 1) marine pipeline route;
2) booster pump location; 3) and transmission main route. The alternative marine
pipeline routes included land segments for conveying Sunrise Lake water by
gravity between the powerhouse on Woronkofski Island and the booster pump
on Wrangell Island. The transmission main considered alternative routes for
conveying water from the booster pump to the treatment plant. Other
evaluations included pipe sizing and booster pump capacity.
TREATMENT CONSIDERATIONS
In the Feasibility Study, a water sample indicated that the quality of Sunrise
Lake's water might qualify for an exemption from filtration. This would mean
that the water would only need to be disinfected. Disinfection of Sunrise Lake's
water could entail either chlorination by itself, or more likely, ozonation coupled
with chlorination. We believe that the latter means of disinfection is needed to
meet the SWTR's Cf requirements and to prevent having potential problems
with taste and odors.
The Feasibility Study considered locating the disinfection system on Woronkofski
Island. However, it is preferred to locate the disinfection system on Wrangell
Island for the following reasons:
• The treatment requirements, including filtration, cannot be established until
fairly extensive and long-term {minimum of one year) water quality testing is
performed. Alaska Department of Environmental Conservation {ADEC)
recently indicated that they will not accept water quality data for purposes of
supporting a waiver from filtration unless it is collected in strict accordance
with their regulations1• Due to the lake's location, obtaining water quality
1 Please refer to correspondence dated May 19, 1998 in Appendix A.
X11~53 Sf.UV98 R'vV'fiECK
SECTION 2
data is costly. Consequently, ADEC s position may preclude the City from
obtaining water quality data that could support a waiver from filtration until
after the water supply facilities are completed. However, the City could
collect water quality data on its own to ascertain whether water quality could
satisfy a waiver. We recommend that the City proceed to obtain water quality
information on Sunrise Lake.
• In the spring of 1999, the City will have commissioned a new 1.3-MGD water
treahnent plant and 400,000-gallon storage tank on Wrangell Island. This
plant has the ability to both disinfect (using ozone and chlorine) and filter
water (slow sand filtration). Due to the uncertainties regarding Sunrise Lake's
water quality and, hence, treahnent requirements, it makes sense for the City
to use these new treahnent facilities rather than having separate and
redundant treahnent facilities on Woronkofski Island. Using the new
treahnent facilities will be more cost effective and, in addition, will provide
some flexibility and advantages to the City. For example, using the new
treahnent facilities will allow the City to use Sunrise Lake's water while
collecting the necessary water quality data to potentially satisfy a waiver from
filtration. If a waiver is later obtained, the City can either bypass filtration or
continue to filter the water as an additional treahnent (precautionary)
measure. Then, when water demands exceed the 1.3-MGD plant capacity,
expansion of the plant's filtration capacity will not be needed. In the event
Sunrise Lake's water quality does not qualify for an exemption, the filtration
system is already there and will be used, then expanded when it becomes
necessary.
• Even though the treahnent facilities can be remotely monitored and
controlled using telemetry (i.e., Supervisory, Control and Data Acquisition, or
SCADA), it will still be necessary for O&M personnel to visit the facilities on a
fairly routine basis (e.g., three or four days a week) to check, repair, adjust and
maintain the plant's equipment. Consequently, maintaining and operating
treahnent facilities on Woronkofski Island, because of its remote location
would be more costly than if located on Wrangell Island.
• Locating the treahnent facilities on Woronkofski Island would place a great
deal of reliance on telemetry for monitoring and controlling the treahnent
facilities. The ability to troubleshoot and quickly resolve the inevitable
problems would be much more difficult than if the treahnent facilities were
close by and readily accessible. It is absolutely essential for the City to have a
safe and reliable potable water supply. Reliability would be compromised if
the facilities were located on Woronkofski Island.
For the above reasons, treahnent facilities on Woronkofski Island are not
recommended; no further consideration is given to treahnent facilities on
Woronkofski Island. Instead, this study focuses on treahnent on Wrangell Island.
2-2 R. W Beck 8/28,198 X110222.353
WATER SUPPLY CONSIDERATIONS
QUANTITY
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
In the original study, the development of the Sunrise Lake Basin was intended to
provide an additional water supply source for the City's future economic
development and growth. Because the City believes that the firm yield of its
existing source has reached capacity and that its limited water source would
discourage industry to come to Wrangell, the amount of water that would be
supplied by Sunrise Lake was "established" at 1.5 MGD. The basis for this figure
was that it would be sufficient to satisfy the demands of the City well beyond the
year 2020, based on its historic growth rate of 1 percent.
It is now recommended that the supply from Sunrise Lake be increased from 1.5
MGD to approximately 3.0 MGD. As the firm yield of Sunrise Lake is
significantly greater than that of the existing source, the City can place greater
confidence on the reliability of this water supply and on the lake providing
additional water expansion as the City's future demands increase above 3.0
MGD. Increasing the supply from Sunrise Lake would provide the City the
option of "abandoning'' its existing source or in using it as an emergency backup.
As the water quality of Sunrise Lake is much better than the existing source,
reduced operating costs would also likely be realized. Another potential benefit
to the City could be in using the existing watershed for other purposes, such as
housing development since available developable land in Wrangell is scarce.
This additional 1.5 MGD supply can be obtained at a relatively modest cost. The
additional cost will be essentially the difference in the cost of the pipe. The
pipeline, instead of being a nominal pipe size of 12 inches for a capacity of 1.5
MGD, would be a nominal pipe size of 16 inches (14.5-inch I.D., SDR 21, HDPE)
for 3.0 MGD(l). The incremental cost increase is estimated to be about 30 percent
($540,000).
MARINE PIPELINE ALIGNMENT
Two alternative alignments were considered for the pipeline between the
proposed powerhouse and Wrangell Island. Alternative No. 1 alignment {see
Figure 3.2 in April 1998 Feasibility Report) is comprised of an overland route
alongside the existing Tyee transmission line on Woronkofski Island,
then crossing the Zimovia Strait at the shallowest and shortest crossing to the
beach head on Wrangell Island about one mile south of Cemetery Point near the
Wrangell Institute. No.2 alternative alignment {see Figure 2-1) is comprised of a
(I) The capacity will be in the 2.8-3.0 MGD range depending on final design parameters of
powerhouse and pump station elevations and coefficient of friction used for final design.
X110222.353 9/1/98 R. W. Beck 2-3
SECTION 2
longer marine pipeline crossing from the proposed marine jetty on Woronkofski
Island to a beach head at about the same location on Wrangell Island.
For both alternatives, a nominal pipeline diameter of 16 inches is being assumed
rather than a 14-inch pipe, as reported in the Feasibility Study. The reason for the
increased size was primarily to account for the location of the booster pump
station, which is to be located in the City Park at Cemetery Point, rather than at
the beach head a mile to the south. Instead of locating the transmission main in
Zimovia Highway on Wrangell Island, we recommend that it be located in the
intertidal zone. The reason for this recommendation is that the Zimovia
Highway was recently reconstructed (1995) and many utilities are located within
the roadway (storm drain, water and sewer), making the construction of the
transmission main in Zimovia Highway difficult and costly. During a conference
call on June 24, 1998, with USFS and ADF~, the resource agencies did not voice
any particular environmental concern that would prohibit construction the water
pipeline in the intertidal zone.
The cost estimates of the alternative pipeline alignments are summarized in the
following table:
TABLE 2-1
SUNRISE LAKE WATER SUPPLY AND HYDROELECTRIC PROJECT
COST COMPARISON OF ALTERNATIVE ROUTES PROJECT
Item
Procure and Install HDPE
Buried Pipeline-Woronkofski (36" Dia.)
Buried Pipeline-Woronkofski (16" Dia.)
Marine Pipeline (16" Dia.)
Buried Pipeline-Intertidal Zone (16" Dia.)
Valve Vault-Woronkofski
Stream Crossings-Woronkofski
Total
Marine Pipeline
Alternative 1
0
760,000
1,264,000
270,000
0
110,000
2,404,000
Marine Pipeline
Alternative 2
$144,000
0
1,880,000
270,000
50,000
0
$2,344,000
The total estimated costs are not appreciably different between the two
alternatives. However, there is a difference in their potential affect to the streams
on Woronkofski Island. For Alternative 1, eight streams on Woronkofski Island
would be crossed by the pipeline. With each of these streams showing evidence
of salmon habitat, care would be needed in the construction of the pipeline
through these streams. Additionally, Alternative 1 would have a potentially
significant impact on one of the streams where power plant discharges of up to
32 cfs would substantially increase the stream flow. Alternative 2 avoids the
stream crossings by directing the pipeline along the proposed access to the
marine jetty. Additionally, this pipeline segment would convey the plant
discharge, in excess of the City's water needs, into the Zimovia Straight rather
than into a stream.
2-4 R. W Beck 9/1/98 X110222.353
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
Based on both cost and environmental considerations, Alternative Alignment
No. 2 is recommended for pipeline construction.
HYDRAULIC
The powerhouse is proposed to be situated at an elevation that maximizes the
power generation potential but still allows the water to be conveyed to Wrangell
Island by gravity. The elevation of the powerhouse was initially established at an
elevation of 140 feet MSL, while the water treatment plant is located at an
elevation of approximately 265 feet MSL. In order to gravity-flow to the water
treatment plant, the powerhouse would have to be located approximately at
elevation 430 feet MSL. This would result in a considerable loss of power
generation potentiaL Furthermore, a HDPE marine pipeline would need to be at
the upper limits of its pressure classification and would be costly to procure and
construct. Consequently, a booster pump station is recommended for
development because it results in less Project Development cost and allows for a
maximum of power potential for the 4.0-MW hydro station.
The final elevation of the powerhouse depends on the location of the booster
pump station. Assuming the booster pump station is at an elevation of 30 feet
MSL on Wrangell Island, the powerhouse will need to be at an elevation of about
140 feet MSL in order to ensure that a flow of 3.0 MGD can be conveyed in a
16-inch (nominal OD) HDPE pipeline. If the pump station is at a higher
elevation, or the powerhouse is at a lower elevation, then the hydraulic capacity
at the water supply pipeline will be reduced.
BOOSTER PUMP STATION LOCATION ALTERNATIVES
There are several potential locations for a booster pump station in the general
vicinity of the proposed beach head of the marine pipeline: in Oty Park, at the
wastewater treatment plant or at the end of (or just beyond) the access road
which is along the northerly boundary of the cemetery.
The selection of a preferred site will need to consider aesthetic and
environmental impacts. Hydraulic considerations will be important as well
because the booster pump location will either affect the capacity of the 16-inch
water supply pipeline or affect the siting of the powerhouse and/or sizing of the
water supply pipeline. As mentioned earlier, the powerhouse is proposed to be
situated at about elevation 140 feet for power generation and cost reasons.
Consequently, the elevation of the booster pump station and the size of the water
supply line need to be considered together and properly balanced.
Another engineering consideration is the establishment of an appropriate
elevation that provides protection from extreme tidal events. It is, therefore,
important to locate the booster pump station well above an elevation that has the
potential of being flooded (say five to ten feet above high tide level).
X110222.353 9/1/98 R. WBeck 2-5
SECTION 2
As mentioned earlier, assuming that the booster pump station on Wrangell Island
is at an elevation of 30 feet MSL, the elevation of the powerhouse would need to
be at approximately 140 feet MSL to assure that 3.0 MGD can be conveyed to
Wrangell Island by gravity in a 16-inch (nominal OD) HOPE pipeline.
The location chosen for conceptual design purposes is a site at the west end of
the existing ceme.tery access road (See Figure 2-2). The elevation of the general
area where the booster pump station could be located varies from approximately
30 to 50 feet MSL. At this location, the effect of noise would be less than if the
pump station were located in City Park.
BOOSTER PUMP STATION DESIGN
Until the City's water demands exceed approximately 80 percent of the capacity
of the plant, it is best to provide a pumping system that more or less matches the
actual system demands and head requirements. The proposed pumping system
would consist of three pumps, each with a capacity of approximately 0.7 MGD.
Two of the pumps would, therefore, be capable of meeting the currently
projected peak day demand. One pump would be standby. Each pump would
have a variable frequency drive that would allow the pumps to match the
variations in flow.
Reasonable provisions can be made in the design of the proposed booster pump
station to allow for future expansion to 3.0 MGD. These provisions include:
• Allow space/provisions for a future pump
• Size and configure piping for future flow
• Select pumping equipment (pumps/motors/variable frequency drives) that
offers some capacity expansion capability (with relatively minor
modifications).
• Size standby power for future load
The booster pump station would be housed in a pre-engineered metal building.
TRANSMISSION MAIN ALIGNMENT ALTERNATIVES
From the pump station, there are two potential routes to the water treatment
plant. One route (Alternative 2) is northerly along Zimovia Highway to the
water treatment plant access road (Wood Street) and then along Wood Street to
the water treatment plant. The other route (Alternatives 1A and 1B) is northerly
along the west side of Zimovia Highway for a short distance, then east along the
cemetery access road and cross-country in a forested area to the water treatment
plant. This alternative was evaluated with and without an access/maintenance
road for the cross-country portion of the pipeline. The alignment of these
alternatives are shown schematically on Figure 2-2.
2-6 R. W Beck 9/1/98 X110222.353
f ,,
,;~-,
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
EVALUATION OF WATER CONVEYANCE ALTERNATIVES
CAPITAL COSTS
Direct construction costs were estimated for each alternative. It is important to
understand that the following cost estimates were based on a "conceptual
design" and without benefit of detailed mapping and geotechnical investigations.
Although every reasonable effort was made to ascertain the system construction
requirements and their associated costs, these estimates are based on
reconnaissance-based information.
Costs were estimated using a variety of sources, including bids, equipment and
material suppliers, contractors and published construction cost data (e.g., Means),
in addition to applying considerable professional engineering experience and
judgment.
The following items/costs have been excluded from this estimate:
• Land/easement acquisition costs
• Phased construction
• Future inflation beyond 1998
• Increasing the capacity of the water treatment plant
• Marine pipeline
Pipe costs include trench excavation, hauling and disposal of unsuitable material,
bedding and backfill. Trench restoration includes saw cutting. The estimates
assume a batch plant is in the Wrangell area. Road excavation/fill includes
drainage ditches. The following additional assumptions were made for the cost
estimates:
• For pipe in Zimovia Highway, all excavated material is unusable. Material is
hauled and disposed off-site. A disposal site is located within 1 to 2 miles of
the project area
• For pipe in Zimovia Highway, all bedding and backfill is imported material
• For both trench and road excavation, it was assumed that all rock can be
excavated/ripped and blasting of rock would not be required (or is minimal)
• For the access road to the WTP, it was assumed that cuVfill is essentially
balanced and in-situ soils are generally suitable for the road's construction
• For the access road to the WTP, it was assumed that the in-situ soils along the
alignment will generally be suitable for the road's foundation (i.e., minimal
muskeg); as such, it will not require the placement of excess shot rock to
stabilize the road's foundation
Xl10222.353 8128/98 R. W. Beck 2-7
SECTION 2
• For the pipe in the access road to the WTP, bedding material is imported; the
majority (50+ percent) of the excavated material was suitable for use as
backfill
• Improvements/modifications required at the WTP to consist of connecting the
16-inch transmission main to the 12-inch influent supply line just outside the
control building
As shown in Tables 2-2, 2-3 and 2-4, the direct construction costs for
Alternatives lA, lB and 2 are approximately $1.21 million, $0.96 million, and
$1.74 million, respectively. The difference in cost between Alternative 1B over the
other alternatives is approximately $0.25 million and $0.78 million.
TABLE 2-2
CONSTRUCTION COST ESTIMATE
TRANSMISSION MAIN ALTERNATIVE 1~1 J
Itenv'Description Unit Qty. Unit Cost Total Cost
CIVIL
16" HOPE Zimovia Highway (Marine Pipeline toP. Sta. Access LF 350 $ 100 $ 35,000
Road)
16" HOPE Pump Station Access Road LF 250 85 21,250
Trench Restoration Zimovia Highway (2" AC/4" ATB/8" SB) SF 1,750 4 6,125
Pump Station Site Clearing & Grubbing AC 0.25 12,000 3,000
Pump Station Access Road Clearing & Grubbing (250 LF x 60') AC 0.35 12,000 4,200
Pump Station Site Grading & Drainage LS 1 15,000 15,000
Pump Station Access Road Grading & Drainage (250 LF 14' LS 1 10,000 10,000
Gravel Rd)
Pump Station Foundation Structural Excavation CY 250 25 6,250
Pump Station Foundation (12" Gravel/3" Sand) CY 140 30 4,200
P. Sta. Potable Water Service Conn. & Piping (250 LF 2" to LS 1 7,000 7,000
Bldg.)
P. Sta. SS/Drain Sewer Service Conn. & Piping (250 LF 6" in to LS 1 9,000 9,000
Bldg.)
P. Sta. Cyclone Fencing (6') LF 400 25 10,000
WTP Access Road Clearing & Grubbing (2600 LF x 60') AC 4 5,000 20,000
WTP Access Road Grading (Excavation/Fill for Subroad) CY 15,000 5 75,000
16" HOPE WTP Access Road LF 2600 60 156,000
16" Gate Valves EA 5 2,000 10,000
Combination Air/Vacuum Valves EA 2 5,000 10,000
6" Drain Valve/Line EA 2 1,500 3,000
Connect to WTP 12-in Influent Supply Line LS 1 3,500 3,500
WTP Access Road Drainage (18"/24" Culverts@ 250' Spacing) LF 360 50 18,000
WTP Access Road Creek Crossing (12' x 5' Multi-plate Arch LF 30 300 9,000
Culvert)
WTP Access Road Culvert Inlet/Outlet Ri_e Ra_e CY 750 15 11,250
(l) Alternative methods cost of booster pump
2-8 R. W Beck 8/W98 Xll0222.353
r·
TABLE 2-2 (Continued)
Item/Description
WTP Access Road Foundation (14' Wide/3' Shot Rock, 24 8")
WTP Access Road Surfacing (14Ft Wide/12-in AB)
WTP Access Road Erosion Control
Subtotal Civil
STRUCTURAL
Pump Station Reinf. Slab-On-Grade (8")
Pre-Engr. MetatBldg. (40' x 60')
8' Interior Walls (Steel Studs/Sheet Rock)
Interior Appurtenances (Doors, Wall Finishes)
Subtotal Structural
MECHANICAL
Pumping Equip. { -0.7MGD, 50 HP Horiz. Split Case Pumps &
Motors)
Pump Station 16" SteeVDI Piping
Pump Station Valves & Appurtenances
Pump Station Aow Meter
Pump Station Hoist (1 Ton TroUey Type)
Pump Station HeatinWVentilation System
Pump Station Sanitary/Drain Sewer Piping & Appurtenances
Pump Station Potable Water Piping & Appurtenances
Standby Engine Generator Fuel Tank
Subtotal Mechanical
ELECTRICAL
Pump Station Building Power & Ughting
Pump Station Pumping Equipment VFDs (50 HP)
Pumping Equipment MCC'Panel
Pumping Equipment Instrumentation & Controls
Pumping Equipment SCADNTelemetry
Pumping Equipment Standby Power {200 kW)
Subtotal Electrical
MISaLLANEOUS
Pump Station Painting (Equipment, Piping, Aoors, Interior
Walls)
Start-Up, Testing & Warranty Items
Mobilization, Bonds & Insurance
Construction Surveying
Traffic Control
Subtotal Miscellaneous
DIRECT CONSTRUCTION COST (rounded)
X110222.353 8128198
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
Unit Qty. Unit Cost Total Cost
CY 4,500 12 54,000
CY 1,500 25 37,500
LS 1 10,000 10,000
$ 548,275
CY 25 $ 325 $ 8,125
SF 2,400 60 144,000
LS 1 5,000 5,000
LS 1 7,500 7,500
$ 164,625
EA 3 12,000 36,000
LF 150 125 18,750
LS 1 35,000 35,000
LS 1 5,000 5,000
LS 1 15,000 15,000
LS 1 15,000 15,000
LS 1 4,000 4,000
LS 1 3,000 3,000
LS 1 5,000 $ 5,000
136,750
LS 1 15,000 15,000
EA 3 25,000 75,000
LS 1 15,000 15,000
LS 1 15,000 15,000
LS 1 20,000 20,000
LS 1 75_000 $ 75,000
215,000
LS 1 25,000 25,000
LS 1 20,000 20,000
LS 1 80,000 80,000
LS 1 20,000 20,000
LS 1 2,000 2,000
$ 147,000
$1,212,000
R. W. Beck 2-9
SECTION 2
TABLE 2-3
CONSTRUCTION COST ESTIMATE
TRANSMISSION MAIN ALTERNATIVE 1 B(l)
Item/Description Unit Qty. Unit Cost Total Cost
CIVIL
16" HOPE Zimovia Highway (Marine Pipeline to P. Sta. Access LF 350 $ 100 $ 35,000
Road)
16" HOPE Pump Station Access Road LF 250 85 21,250
' Trench Restoration Zimovia Highway (2" AC/4" ATB/8" SB) SF 1,750 4 6,125
Pump Station Site Clearing & Grubbing AC 0.25 12,000 3,000
Pump Station Access Road Clearing & Grubbing (250 LF x 60') AC 0.35 12,000 4,200
Pump Station Site Grading & Drainage LS 1 15,000 15,000
Pump Station Access Road Grading & Drainage (250 LF 14' LS 1 10,000 10,000
Gravel Rd) ;-
Pump Station Foundation Structural Excavation CY 250 25 6,250
Pump Station Foundation (12" Gravel/3" Sand) CY 140 30 4,200
P. Sta. Potable Water Service Conn. & Piping (250 LF 2" to Bldg.) LS 1 7,000 7,000
P. Sta. 55/Drain Sewer Service Conn. & Piping (250 LF 6" in to LS 1 9,000 9,000
Bldg.)
P. Sta. Cyclone Fencing (6') LF 400 25 10,000
WTP Clearing & Grubbing (2000 LF x 60') AC 2.5 5,000 12,500
16"HDPEWTP LF 2000 60 120,000
16" Gate Valves EA 5 2,000 10,000
Combination AirNacuum Valves EA 2 5,000 10,000
6" Drain Valve/Line EA 2 1,500 3,000
Connect to WTP 12-in Influent Supply Line LS 1 3~0 3,500
Erosion Control LS 1 10,000 6,000
l .
Subtotal Civil $ 260,025
STRUGURAL
Pump Station Reinf. Slab-On-Grade (8") CY 25 $ 325 $ 8,125
Pre-Engr. Metal Bldg. (40' x 60') SF 2,400 60 144,000
8' Interior Walls (Steel Studs/Sheet Rock) LS 1 5,000 5,000
Interior Appurtenances (Doors, Wall Finishes) LS 1 7,500 7,500
Subtotal Structural $ 164,625
MECHANICAL
Pumping Equip. (-0.7MGD, 50 HP Horiz. Split Case Pumps & EA 3 12,000 36,000
Motors)
Pump Station 16" Steel/DI Piping LF 150 125 18,750
Pump Station Valves & Appurtenances LS 1 35,000 35,000
Pump Station Flow Meter LS 1 5,000 5,000
Pump Station Hoist (1 Ton Trolley Type) LS 1 15,000 15,000
Pump Station HeatingNentilation System LS 1 15,000 15,000
Pume Station Sanitary/Drain Sewer Pieing & Appurtenances LS 1 4,000 4,000
(I) Alternative methods cost of booster pump
2-10 R. W Beck 8/28198 Xll0222.353
TABLE 2-3 (Continued)
I tem!Description
Pump Station Potable Water Piping & Appurtenances
Standby Engine Generator Fuel Tank
Subtotal Mechanical
ELECTRICAL
Pump Station Building Power & lighting
Pump Station Pumping Equipment VFDs (50 HP)
Pumping Equipment MCCIPanel
Pumping Equipment Instrumentation & Controls
Pumping Equipment SCADNfelemetry
Pumping Equipment Standby Power (200 kW)
Subtotal Electrical
MISCELLANEOUS
Pump Station Painting (Equipment, Piping, Floors, Interior
Walls)
Start-Up, Testing & Warranty Items
Mobilization, Bonds & Insurance
Construction Surveying
Traffic Control
Subtotal Miscellaneous
DIRECT CONSTRUCTION COST (rounded)
Xll0222.353 812&'98
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
Unit Qty. Unit Cost Total Cost
LS 1 3,000 3,000
LS 1 5,000 5,000
$ 136,750
LS 1 15,000 15,000
EA 3 25,000 75,000
LS 1 15,000 15,000
LS 1 15,000 15,000
LS 1 20,000 20,000
LS 1 75,000 75,000
$ 215,000
LS 1 25,000 25,000
LS 1 20,000 20,000
LS 1 80,000 80,000
LS 1 20,000 20,000
LS 1 2,000 2,000
$ 147,000
$ 923,000
R. W Beck 2-11
SECTION 2
TABLE 2-4
CONSTRUCTION COST ESTIMATE
TRANSMISSION MAIN ALTERNATIVE i 1 l
Item/Description Unit Qty. Unit Cost Total Cost
CIVIL
16" HOPE Zimovia Highway (Marine Pipeline toP. Sta. Access LF 350 $ 100 $ 35,000
Road)
16" HOPE Pump Station Access Road (to P. Sta.) LF 250 85 21,250 r --.
Trench Restoration Zimovia Highway (2" A Cf4" ATB/8" SB) SF 1,750 4 6,125
Pump Station Site Clearing & Grubbing AC 0.25 12,000 3,000
Pump Station Access Road Clearing & Grubbing (250 LF x 60') AC 0.35 12,000 4,200
Pump Station Site Grading & Drainage LS 1 15,000 15,000
Pump Station Access Road Grading & Drainage (250 LF 14' LS 1 10,000 10,000
Gravel Rd)
Pump Station Foundation Structural Excavation CY 250 25 6,250
Pump Station Foundation (12" Gravel/3" Sand) CY 140 30 4,200
P. Sta. Potable Water Service Conn. & Piping (250 LF 2" to Bldg.) LS 1 7,000
P. Sta. SS/Drain Sewer Service Conn. & Piping (250 LF -6" to LS 1 9,000 9,000
Bldg.)
P. Sta. Cyclone Fencing (6') LF 400 25 10,000
16" HOPE Pump Station Access Road (from P. Sta.) LF 250 85 21,250
16" HOPE Zimovia Highway LF 5,100 100 510,000
16" HOPE Exist WTP Access Road LF 3,400 60 204,000
Trench Restoration Zimovia Highway (2" ACf4" ATB/8" SB) SF 25,500 4 89,250
16" Gate Valves EA 10 2,000 20,000
Combination AirNacuum Valves EA 4 5,000 20,000
Drain Valves/Piping EA 3 1,500 4,500
Connect to WTP 12" Influent Supply Line LS 1 3,500 3,500
Subtotal Civil $1,003,525
STRUCTURAL
Pump Station Rein£. Slab-On-Grade (8") CY 25 325 8,125
Pre-Engr. Metal Bldg. (40' x 60') SF 2,400 60 144,000
8' Interior Walls (Steel Studs/Sheet Rock) LS 1 5,000 5,000
Interior Appurtenances (Doors, Wall Finishes) LS 1 7,500 7,500
Subtotal Structural $ 164,625
MECHANICAL
Pumping Equip. ( -0.7 MGD, 50 HP Horiz. Split Case Pumps & EA 3 $12,000 $ 36,000
Motors)
Pump Station 16" Steei/DI Piping LF 150 125 18,750
Pump Station Valves & Appurtenances LS 1 35,000 35,000
Pump Station Flow Meter LS 1 5,000 5,000
Pump Station Hoist (1 Ton Trolley Type) LS 1 15,000 15,000
Pump Station HeatingNentilation System LS 1 15,000 15,000
Pume Station Sanitary/Drain Sewer Pieing & Af!eurtenances LS 1 4,000 4,000
(l) AJtemative methods cost of booster pump
2-12 R. W. Beck 8/28198 X11 0222.353
TABLE 2-4 (Continued)
Item/Description
Pump Station Potable Water Piping&: Appurtenances
Standby Engine Generator Fuel Tank
Subtotal Mechanical
ELECTRICAL
Pump Station Building Power&: Ughting
Pump Station Pumping Equipment VFDs (3-50 HP)
Pumping Equipment MCOPanel
Pumping Equipment Instrumentation &: Controls
Pumping Equipment SCADA/felemetry
Pumping Equipment Standby Power (200 kW)
Subtotal Electrical
MISCELLANEOUS
Pump Station Painting (Equipment, Piping, Floors, Interior
Walls)
Start-Up, Testing & Warranty Items
Mobilization, Bonds & Insurance
Construction Surveying
Traffic Control
Subtotal Miscellaneous
DIRECT CONSTRUCTION COSf(rounded)
X110222.353 8128198
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
Unit Qty. Unit Cost Total Cost
LS 1 3,000 3,000
LS 1 5,000 5,000
$ 136,750
LS 1 15,000 15,000
EA 3 25,000 75,000
LS 1 15,000 15,000
LS 1 15,000 15,000
LS 1 20,000 20,000
LS 1 75,000 75,000
$ 215,000
LS 1 25,000 25,000
LS 1 30,000 30,000
LS 1 125,000 125,000
LS 1 12,000 12,000
LS 1 30,000 30,000
$ 222,000
1,742,000
R. W Beck 2-13
SECTION 2
ENGINEERING AND CONSTRUCTION ISSUES
Potential and foreseen engineering and construction issues associated with each
of the alternatives are as follows:
ALTERNATIVES 1A AND 1 B
• Construction of the access road (for Alternative 1A) and transmission main
may involve rock excavation that could require blasting in certain areas. If
extensive blasting were required the construction costs would be higher than
estimated.
• Construction along a more direct route
(Alternative 1B) will still require clearing of
construction equipment.
ALTERNATIVE 2
without an access road
the forest and access for
• Construction of the transmission main in the highway could require blasting
in certain areas. Except in residentiaVcommercial areas, blasting is not
considered to be a major issue. If needed in residentiaVcommercial areas,
appropriate measures and precautions would have to be taken. If extensive
blasting were required the construction costs would be higher than estimated.
• Because extensive utilities are present in Zimovia Highway (i.e., sewer, water
and storm drains), construction in the highway would be more difficult and
present more challenges than constructing the pipeline in Alternative 1.
PERMITTING/ENVIRONMENTAL ISSUES
Potential and foreseen permitting and environmental issues associated with each
of the alternatives are as follows:
ALTERNATIVES 1A AND 1 B
• Construction of the booster pump station, pipeline and access/maintenance
road from the booster pump station to the water treatment plant will likely
require a U.S. Army Corp of Engineers 404 permit because of the potential for
impacting wetlands and disposal of waste materials.
• In order to construct the pipeline and possibly an access road to the water
treatment plant, a fairly major stream (Robins Creek) will have to be crossed.
Given that culverts presently exist on this stream (under Zimovia Highway,
downstream from the proposed crossing), it is believed that fish passage
mitigation measures will not be a major issue. Alaska Department of Fish and
Game approval will be required for construction activities in this stream
crossing.
• Construction of the transmission main in Zimovia Highway will require
approval and a permit from the Alaska Department of Transportation
(ADOT). Because Zimovia Highway was recently reconstructed (1995),
2-14 R. W Beck 8/2&'98 X110222353
r·-.
!.
r·
IDENTIFICATION AND
EVALUATION OF ALTERNATIVES
ADOT has a standard policy of not allowing construction in the road for a 5-
year period (essentially a moratorium). Because the length of pipeline in the
highway is limited (-300 feet) and because construction will occur just after
this five-year moratorium period, it is anticipated that gaining permission for
this construction will not be a major issue.
• Preliminary information has not identified any eagle nests in the project area.
If an eagle nest tree is found in the area, the location of the booster pump
station or the access road will be adjusted or other appropriate mitigation
measures will be provided during construction. The presence of an eagle nest
in the area should not be a major issue.
• A wetlands survey of the route will need to be conducted to determine
whether the booster pump station site or pipeline/access road will impact
wetlands. It is thought that by adjusting either the location of the booster
pump station or the pipeline/access road, those areas where wetlands exist
could be avoided.
• A survey will need to be conducted along the route to determine whether
cultural resources are present in the project area.
• An endangered plant and animal survey will need to be conducted along the
route to determine whether endangered plants or animals are in the project
area. Areas where such plants exist can be avoided by adjusting either the
location of the booster pump station or the pipeline/access road. Because of
the nearby construction of the water treatment plant and roads as well as the
presence of the highway, quarry, treatment plant, park, etc., the likelihood of
a problem with endangered animals in the project area is considered remote.
ALTERNATIVE 2
Construction of the transmission main in Zimovia Highway will require approval
and a permit from the Alaska Department of Transportation (ADOT). Zimovia
Highway was recently reconstructed (1995), and ADOT has a standard policy of
prohibiting construction in the road for a 5-year period (essentially a
moratorium). Because the length of pipeline in the highway is considerable
(-5100 feet), gaining ADOT's permission for the construction of this portion of
the pipeline may be a major issue. However, construction of this pipeline would
occur after the five-year ADOT moratorium period.
OTHER ISSUES
ALTERNATIVES 1AAND 18
• The City owns the land where the proposed booster pump station and
pipeline/access road are situated. Consequently, easements or land
acquisition will not be required.
Xll0222.353 8128198 R. W Beck 2-15
l
t
' f
f
i
t
t
I
SECTION 2
• Based on the USFS quadrangle map, the pipeline/access road route appears to
be well outside the US Forest Service boundary, so a Special Use Permit from
the Forest Service will not be required for construction.
RECOMMENDED TRANSMISSION MAIN ALTERNATIVE
Alternative lA and 1B are estimated to cost less than Alternative 2.
Because Alternative lA involves the construction of an access road, it has greater
environmental impacts than Alternative 2. The environmental impacts, while
impossible to eliminate entirely, can be mitigated. For example, the City may
elect not to have an access road along the pipeline for maintenance
(Alternative lB). This would not only reduce environmental impacts by reducing
the effect on lands and minimizing the effect of a stream crossing, but also reduce
the total construction costs by about $460,000 over Alternative lA.
Therefore, Alternative lB is the recommended alternative.
2-16 R. W Beck 8/28198 Xl10222.353
r
•
-..:_;
......
;:::·-'"
:~~
I •
~ .. : ....
n.
0
0
0
' ' \ i u
.. · .. -. '; ·.•. ~
': ·.--· :.-
LEGEND
e • • • • • • • • EXISTING 138KV TRANSMISSION LINE
----MARINE PIPELINE
PROPOSED PENSTOCK ALIGNMENT
PROPOSED POWERHOUSE LOCATION
MAP SOURCE: U.S.G.S. QUADRANGLE, PETERSBURG, B-2, 1965 .. · -.:----:-. --:-.·-·-
., ..
.. :~·
~·
.:·
.:
-.
· ... -. :-·' ..
'· ::-··
,; -: .. ! ..... _~. ';!.·.~~."/.
..... ·-),. .. _ ... ;oo. ._ ...... ' ---<
>·
--~~~-: .:;._.:~~:-·~ =-~-~~~~t·
'·~. ~ J ~, • : .. ~-:~·:·-~;-~;~;~:{~.,~
. -:_.; . •J: !~ ,~-~-;~ :::-
,~16~ .:'}~:~,_'~·:·:' · ..
' ••... !. -~; ... -.... 0 :
-.. ~-.o_ .. ...~~ :f: -~ f" -~·.. • • . ;,.. .... _ ... ::: .... ·· -_ .. ~ ··~--~~~/: .~ ~;~~~:·~~~:; ~~j ~:~~~:r:;:'
-.:. ... # ~"" .. -..... • __ ..
-~---·-.. ""'(~ .. -... = •·..; "'·-·~ ~ ·: ~ \ .. -=:__ • ...,.-; :
-· ..... -. ... ~-~·-. ; ... · ..
. ··;
·:.;,..·
.. --~· '.··~-_-: ... ·.: .:
·.· .. -,. ,, "->~~t: .> ~/'!': ,: 'J~~L£~~,;;;:;~£~~r:~~;;~~-:
' ·.·;:·."'-' ------~-·. •.· •.•. ,_ ·····:>-: .-... ·.-·--· • ··,-.;;..-~--.• . ·--~:· ·-·~· -·-':~;.!;''""_:"'':;.~ •· .. · .·.
. . . . _a ~.':~\:.... . • -. .; . ~ , MARU<E>·pn;~~j~:~o·s'
t/ X -~·.::-;: ·---·=·:-"::::~~.:~.,.;~-~~: . ··'--~""'--
, ·.:: ,. ·." . :~ :(-::~; ':'7'"
-.,? .-.-.-
. .._f.__._ .. ..:_ .-;__! ---,"'"':._•
,..,·.:.
;~ ......
'.
~
.. ;~_~fit§{~--:-.. ~' ·-.~~-
.. : .. l
····~ -... ::~ ~: ..
.... -:..:; .....
·I'_;
SCALE: 1-..;,1!2 Mile '±
~ -·· .
FIGURE2-1
CITY OF WR.~NGELL, ALASKA
PENSTOCK/WATER SUPPLY
PIPELINE ALIGNMENT
S3Ail VN~3.L 1V
.L03ro~d
V>ISV"lV '1'139NWM :K) A.LIO
~-~3l::ln~
~ 3J\LLVN1::13.L 1V 'lN3.,N911V
Nlvr4 NOISSir,tSNW.l1::13.LVM
" ""------"··--------,
' ,_
' , _
_ ,
' '
I
' '
113/DN'V&/M
'·-·-....
"V ~ 3J\LL vN~.i 1V NVH.i 3.Ln01::1
.1031::110 31::1~ V SYH 'OVOl::l SS300V
NV .LnOH.UM Sl HOIJ;IM '8 ~ 3/ill.VN1::13.L lV
\_ =3.LON
'•, ........ ~ ....... _ ......
..............
'• ·,
'\
' /
'
/
/ ______ ,
/
J
0
D .:
I
I
: I -
•
~ .
•
SECTION 3
FUTURE WATER SUPPLY SYSTEM IMPROVEMENTS
WATER TREATMENT PLANT EXPANSION REQUIREMENTS
The water treatment plant has a capacity of 1.3 MGD. Sunrise Lake's water
supply pipeline will have a capacity of 3.0 MGD. This means that the water
treatment plant (or portions thereof) would eventually need to be expanded by
approximately 1.7 MGD to take full advantage of Sunrise Lake's water supply.
In terms of space, the existing site offers limited expansion capability. There is
very little extra buildable space at the water treatment plant site, and the
topography in the general vicinity is such that fairly significant cutting and filling
would be required to develop additional space.
If the water quality of Sunrise Lake meets the SWTR and the City is successful in
obtaining a waiver from filtration, expanding the plant's disinfection system
capacity (ozone and chlorination systems) would be possible at the existing site.
If filtration is required, and low-rate sand filtration were to be used, a
considerable amount of space would be needed. It is doubtful that the existing
site could feasibly be expanded to accommodate this type of filtration process.
Rather, it is more likely that high rate filtration would be used. If this is done,
there are two design approaches. The first would continue to use the existing
low-rate, slow sand filtration facilities and add new high rate filtration to meet
future demands. The second approach would replace the low rate, slow sand
filtration facilities completely because of the difficulties in operating and
maintaining two very different kinds of filtration facilities. Accordingly, the high
rate filtration system would be sized to have a capacity of 3.0 MGD. In the latter
approach, expanded facilities would use the area that the slow sand filtration
system occupies. Alternatively, the site could be expanded and the slow sand
filtration facilities used as roughing or polishing filters and as emergency backup
filtration.
For the purposes of this study, the costs for two potential treatment alternatives
were investigated: expanding disinfection, and expanding with disinfection and
high rate filtration. In the latter case, it was assumed that the low rate, slow sand
filtration system would be used as roughing or polishing filters, and the site
expanded to accommodate 3.0 MGD high-rate filtration plant. We estimated the
construction costs would be about $1.7 million for disinfection only, and
$5.0 million for disinfection and high-rate filtration.
WATER SYSTEM IMPROVEMENTS
In addition to the new treatment plant, the Water system improvements being
constructed this year include a new 400,000 gallon water tank, finished water
pumps, a pipeline to the new tank, and a new main to the City's existing·
Xll 0222.353 8/2!V98 fi'\V·~ECK
SECTION 3
distribution system. All these facilities are sized to provide approximately
1.3 MGD of treatment capacity. In order to supply 3.0 MGD, certain
improvements will be required:
• Booster Pump Station. The proposed booster pump station on Cemetery
Point will be sized to pump a maximum of 1.3 MGD. When actual water
demands exceed approximately 80 percent of the capacity of the treatment
plant, it is recommended that additional pumping capacity be added to the
station.
• Storage. The City's new 400,000 gallon water tank together with distribution
storage that already exists meets the City's current and projected finished
water storage requirements up to demand o 1.3 MGD. When demand
increases above 1.3 MGD, consideration should be given to providing more
finished water storage.
The new 400,000 gallon tank will be connected to the city's distribution
system by a 12-inch water main. As demand increases the capacity of this line
may become inadequate. At that time, it is recommended that a water system
analysis be under taken to determine the best means of increasing water main
capacity between the treatment plant and the finished water tank and the
distribution system.
• Plant Finished Water Pumping. The new Plant's finished water pumping
station conveys water from the treatment plant to the new 400,000 gallon
tank. When demand starts to exceed the 1.3 MGD design capacity, additional
finished water pumping will be required.
• Main from Plant to Town. When the City's hydraulic model is updated and
completed, the capacity of the 12-inch HDPE water supply line that runs from
the water treatment plant to town can be determined. When its full capacity
is utilized, a parallel supply line will need to be installed.
3-2 R. W. Beck 8128198 X110222.353
. ,
JL'-I I'-·""' -r
ESTIMATED CONSTRUCTION COST AND SCHEDULE
GENERAl
Cost estimates for the Project were prepared for the selected project arrangement
based on the preliminary conceptual design layouts and details shown in Fig. 2-1
of this addendum and Figs. 5-1 through 5-4 of the Feasibility Study, and based on
our opinion of geotechnical site conditions. The estimated project cost was
determined by preparing a Direct Construction Cost estimate, applying indirect
costs to arrive at the Total Construction Costs, applying interest during
construction to determine the Total Investment Cost and making a final
adjustment for escalation to arrive at the Total Investment Cost for the scheduled
on-line date of December 31, 2000.
BASIS OF COSTS
DIRECT CONSTRUCTION COST
This cost includes the total of all costs directly chargeable to the actual
construction of the project, which, in essence, represents a contractor's bid based
on a January 1998 bid price level.
The Direct Construction Cost was developed based on unit prices from actual
contractor's bids on similar projects, adjusted to reflect location, project size and
bid price level and applied to quantities estimated for the major construction
features. Costs for turbine, generator and pipeline procurement were based on
preliminary quotations from equipment suppliers, catalog values and adjusted
with experience costing data. The estimated direct construction cost for the civil
features (with the exception of the water pipeline) were verified by an
independent estimate prepared by a cost estimating consultant experienced in
preparing estimates for contractors on hydroelectric projects and other major
civil works projects.
CONTINGENCIES
To allow for unforeseen difficulties during construction and items not reflected in
the estimate, a 25 percent contingency allowance was applied to the Direct
Construction Cost. If the Project were developed under a two-season
construction schedule, as described under "Design and Construction Schedule"
of this report, then we feel that the construction contingencies could be reduced
to 20 percent. With a compressed schedule, we anticipate more claims and
change orders to the civil works contracts.
XI10222353 8128198 fi'W'~ECK
SECTION 4
ENGINEERING AND OWNER ADMINISTRATION
The Engineering and Owner Administration Costs are based on actual experience
with costs for similar work. This item includes all preliminary engineering work,
project feasibility and environmental studies; field investigations, processing of
required permits and licenses; final design and preparation of construction
contract documents; inspection of construction; and owner administration. An
allowance of 20 percent of the sum of the Direct Construction Cost plus
contingencies is considered a reasonable estimate for this item.
TOTAL CONSTRUCTION COST
The Total Construction Cost includes the Direct Construction Cost plus
contingencies and Engineering and Owner Administration.
ESCALATION
As discussed previously, the Total Construction Cost is based on a January 1998
bid price level and includes assumed escalation of prices expected during the
construction period. Since the earliest practical date for bidding major contract
items for the Project is January 2000, escalation is applied for the intervening
period of one year to adjust the estimated Total Construction Cost to the actual
bid date. Escalation was assumed at an average of 3 percent per year for the
purpose of this estimate.
INTEREST DURING CONSTRUCTION
Interest During Construction was determined from an empirical formula that
considers cash flow expenditure for a typical hydroelectric project, the project's
construction duration and the prevailing interest rate. The interest rate during
the construction period was assumed at 6 percent per year:, which is the same rate
assumed for a long term revenue bond.
TOTAL INVESTMENT COST
The Total Investment Cost is the sum of the Total Construction Cost plus Interest
During Construction. Total capital requirements are based on a 30-year, 6 percent
tax-deferred revenue bond. The total capital requirements include the Total
Investment Cost plus a reserve fund equal to one year of debt service.
CONSTRUCTION COST ESTIMATE
A cost estimate summary is shown in Table 4-1. Detailed Direct Construction
Cost estimates are shown in Appendix 2. The estimated Total Construction Cost
for the Project with a bid date of January 2000, corresponding to a construction
completion in December 31, 2000, is $15,970,000.
4-2 R. W. Beck 8128198 X110222.353
f '
"
. ...
r"~
I
t
ESTIMATED CONSTRUCTION COST AND SCHEDULE
TABlE 4-1
SUNRISE LAKE WATER SUPPlY AND HYDROElECTRIC PROJECT
CONSTRUCTION COST ESTIMATE SUMMARY
FERC Total
Account Project Water Hydro
Code Description Cost Component Component
60 MOBILIZATION $ 335,000 $ 188,000 $ 147,000
330 LAND AND LAND RIGHTS
331 STRUCI1JRES AND IMPROVEMENTS
331.1 Powerhouse 519,000 52,000 467,000
331.2 Switch yard 100,000 100,000
332 RESERVOIR, DAM AND WATERWAY
3321 Reservoir 44,000 44,000
332.2 Dam, Concrete-Faced Rockfill 278,000 278,000
332.3 Waterway
33231 Siphon Intake 295,000 249,000 46,000
33232 Penstock 1,982,000 1,216,000 766,000
. 332.33 Water Supply/Marine Pipeline 2,344,000 2,344,000
33234 Booster Pump and Transmission Main 923,000 923,000
333 TURBINES AND GENERATORS 1,220,000 1,220,000
334 ACCESSORY ELECTRICAL EQUIPMENT 110,000 40,000 70,000
335 MISCELLANEOUS POWER PLANT 190,000 100,000 90,000
EQUIPMENT
336 ROADS, JETTY 299,000 299,000
380 TRANSMISSION & INTERCONNECTION 1,395,000 20,000 1,375,000
DIRECT CONSTRUCTION COST (Bid 1198) $10,030,000 $5,750,000 $4,280,000
(rounded)
Contingencies 2,510,000 1,440,000 1,070,000
Engineering & Owner Administration 2,510,000 1,440,000 1,070,000
TOTAL CONSTRUCTION COST (Bid 1/98l $15,050,000 $8,630,000 $6,420,000
Escalation 920,000 530,000 390,000
TOTAL CONSTRUCTION COST (Bid 1/00) $15,970,000 $9,160,000 $6,810,000
Interest During Construction 230,000
TOTAL INVESTMENT COST (BQ1JI'l<.ied) $7,040,000
X110222.353 8128198 R. W. Beck 4-3
SECTION 4
DESIGN AND CONSTRUCTION SCHEDUlE
GENERAL
A design and construction schedule developed for the project is shown in
Fig. 4-1. This schedule contemplates commercial operation of the hydro turbine-
generating unit by December 31, 2000, which is considered to be the earliest
possible date considering the time required for additional feasibility
investigations, preparation and processing of the FERC License Application,
design and construction. This is a year later than what had been reported in the
Feasibility Study. However, USFS and ADFG are requesting fish surveys and
instream flow study of Sunrise Creek that could take one year to complete.
If notices to proceed by the dates indicated are not met soon, then project
construction would likely be delayed into the next season. The staging of the
contracts is based on necessary lead times for fabricating the turbine-generator
equipment, the marine pipeline, the penstock pipe and the powerhouse building.
As shown in Fig. 6-1, the start of procurement activities would need to commence
before FERC issues an exemption order, which is financially risky. Furthermore,
the schedule contains a large number of critical work activities that will likely
cause higher costs for design and construction due to additional change orders
and claims.
If the schedule was given an additional year to complete, then it would be
desirable to delay award of contracts until the FERC issues the license order.
Also, it would be very desirable to have a two-season construction period, where
in the first season, a limited civil works contract would be issued to construct the
access road, excavate the powerhouse foundation, install the port facility, and
clear the timber along the penstock right-of-way. Then, the civil works
contractor can readily be underway at the outset of the following year. He would
have more lead time to plan his work and procure materials. His work scope
would be better defined, since the powerhouse structure's excavation work is
completed. With more float time in the performance of each work activity, the
contract price would invariably be lower.
DESIGN AND CONTRACT DOCUMENTS
Final design activities would need to commence on about July, 1999 (see Fig. 4-1)
in order to complete the Project construction during the year 2000 season. The
work would be divided up into three contracts, which are as follows:
• Contract !-Procurement of Turbine-Generator equipment
• Contract 2-Civil Works (includes, headworks, powerhouse, penstock,
installation of turbine-generator, miscellaneous mechanical and electrical
equipment, and telemetry)
• Contract 3--Water Supply Pipeline (including booster station)
4-4 R. W. Beck 8/28198 X110222.353
r
-
'~
r-
, . ' u
.. ,
r
l.J
t
••
i • .......
ESTIMATED CONSTRUCTION LOST AND SCHEDULE
CONSTRUCTION
Figure 4-1 shows a schedule of the construction activities for completing the
Project by January 2001. Fabrication of the turbine-generator equipment would
commence on November 1, 1999, which is well ahead of when the FERC could
issue the license order. The suppliers have indicated a 12-month lead time before
the last turbine-generator component is delivered. However, we are assuming
that initial embedded turbine parts would arrive before September 1, 2000.
Other construction activities that would need to commence prior to the license
order include fabricating the penstock, fabricating the powerhouse
superstructure, constructing the marine jetty and access road to the powerhouse
and initiating the construction of the water pipeline. Should the FERC dictate
design changes to the Project, cost implications to both design and construction
could very well occur.
Construction of the primary structures (dam and intake siphon, penstock and
powerhouse) is assumed not to start until June 1, 2000, when it is assumed that
the FERC would issue the license order. The major civil works construction
activities would be completed by October 31, 2000, leaving 2 months to install the
remainder of the powerhouse mechanical and electrical equipment and to
.Perform all necessary start-up and commissioning tests.
X110222.353 8/28198 R. W Beck 4-5
s_vs H:\YAA\Y,t.,,t.,01JI8 8-21·-01 0 U·J8
r---------------------------------------------------------····---------.
FIGURE 4·1
SUNRISE LAKE WATER SUPPLY AND HYDROELECTRIC PROJECT
DESIGN AND CONSTRUCTION SCHEDULE
ACTIVITY
LICENSING PHASE
first Stage Consultation.
Second Stage Consultation .. .
Third Stage Consultation ................... .
bmit l'illol Jicense Applidotion
, ; ' · ! ,_;.__ ls$ue !>I license Order ................. .
Preliminary Design... . ........ . ...~l,..
i i
DESIGN PHASE
Contract 1
(Turbine/Generator Procurement) ............. .
Contract 2 (Marine Pipeline). . . .. . . . .. .. ... , ..
I
I I ' ., ' I I I ! 1 ! 1 j ; i i u..J lssJe ! :
.. j... I i I '1
1 I l lssJe 1
• I I I ' I ;
Contract 3 (Civil Works) ............................ ..
"l'"i·---~---r .. ! tIssue ... , .... f.... ..... . , ! I I
CONSTRUCTION PHASE
Access Rood/Pier .. . . . .. . .. . ...
Mobilization ..... .
Heodworks facility .................... ..
Powerhouse Excavation ....
Powerhouse Concrete .....
Turbine/Generator ....... .
Install Powerhouse Building ............ .
Penstock ..... .
Water Pipeline. .. . . .. .. . . .....
Transmission Interconnection.
J F M A M J
i'
I I 'I I i I l I i
I I I I i I I ! I I l J : ; ! . :
l \ \ I l ~ \ ~. l l Awor<l
j'ji il 1,~:·
"1"" .... '"'1''" --·+·+·· .... , ... .V. .. j ... -..;-
1 I i ' I I I I
,Wor~s
·····l•···rt·.·.·.r·····r···l····· ·······I•··i·.·.··I···~····!·.·J : i
. .. 'I' .... , ... ·l· . T... . .. r .. ·!",\~~;d· '!~~b~~~i~~~~~~J .Pr6~~;.merlt •
···!····l····l····l···· .... V.T. -···1-···i····l····'···-~-·-······'·····• -•. ·--~
. .. J.. .. : ... ; ..... '.. ; ... 1. ...... J.. _!Fobflcot¢ B~ilding .· =
:Unit on -Line
I i I : ! irabfleot~ Pi~e !~stall Penst~k
···l···l .. j ••• J ••••••• ····f··· ····: ' . ' . : . :
I i i j ! Avl.ord ~lpe!lne i ln~talli Plp•llne i
--··i····l···-1-··"i'''' ... ····:········f"'l'"'l"'' •, .. , --·
...L.L.L.L. .... L ..... LJJ .. : .. J.., . ....-.
M J J A S 0 N 0 J F M A M J J A S 0 N D
~ ... ,
.J ; :J ..,
,J &
. ~11&11[ @~ ~~~~~[~~
DEPT. OF ENVIRONMENTAL CONSERVATION
DIVISION OF ENVIRONMENTAL HEALTH
DRINKING WATER and WASTEWATER PROGRAM
410 WILLOUGHBY AVENUE, SUITE 105
JUNEAU, ALASKA 99801 RECEIVED
May 19, 1998
RWBeck
Mr. Reed Kelly,P.E.
1001 Fourth Avenue, Suite 2500
Seattle, WA 98154-1 004
MAV 2 2 1998
A.W. BECK
SEATTLE. WA
TONY KNOWLES, GOVERNOR
Telephone: (907) 465-5335
FAX: (907) 465-5362
Re: Sunrise Lake Water Quality Program, Wrangell, Alaska
Dear Mr. Kelly:
Thank you for your E-mail dated May 15, 1998. The department appreciates the
opportunity to clarify the issues regarding your request to purchase and use a
turbidimeter, which we discussed, does not meet water standards referenced in the
drinking water regulations.
The Department of Environmental Conservation's Drinking Water Regulation 18 AAC
80.255 states:
(d) Only the analytical methods set out in this subsection may be used to
demonstrate compliance with the requirements of 18 AAC 80.500-18 AAC
80.590 (Surface Water Treatment Rule) ... The following procedures must be
performed in accordance with the publications listed for each procedure, the
provisions of which are incorporated by reference in this chapter:
(1) Turbidity: by Method 214A (Nephelometric Method-Nephelometric Turbidity
Units) as set out at pp. 134-136 of Standard Methods for the Examination of
Water and Wastewater, 1985, American Public Health Association, 16th edition.
The City of Wrangell has the right to purchase and use any turbidimeter they choose.
Wrangell also has the opportunity to pursue the establishment of a new water source
and apply for filtration avoidance following the Criteria for Avoiding Filtration as set out
in 18 AAC 80.520.
The department will base its filtration avoidance decision on information collected with
an instrument which meets specific standards and with data which has been collected
per the state regulations as we have done for other systems.
printed on recycled paper by C. D.
RW Beck and the City of Wrangell are invited to call me if they have questions about
the state regulations regarding filtration avoidance. I can be reached at (907) 465-
5335. A copy of the state drinking water regulations and also the standard methods for
turbidity measurement are enclosed for your convenience.
Sincerely,
~c£5r-
Kathleen Saga
Environmental Specialist
Drinking Water and Wastewater Program
cc: City of Wrangell, Bob Caldwell
enclosure: State of Alaska Drinking Water Regulations
Standard Methods, section 2130 B
""
!1-t
!'l
... ..
r· I ;
r1
'
,:'~-
r~ ...
r
i
60
331
331.1
331.2
332
332.1
332.2
332.3
CONSTRUCTION COST ESTIMATE
BACKUP FOR TABLE 4-1
SUNRISE LAKE WATER SUPPLY AND HYDROELECTRIC PROJECT
CONSTRUCTION COST ESTIMATE
PROJECT ALTERNATIVE WITH 4.0 MW HYDRO UNIT
Unit
Item/Description Quantity Unit Price Amount
MOBIUZA TION LS 335,000
STRUCfURES AND IMPROVEMENTS
Powerhouse
.01 Oearing LS 10,000
.02 Excavation
a. Common 1,200 CY 20.00 24,000
b. Rock 380 CY 90.00 34,000
.03 Concrete Substructure 340 CY 600.00 204,000
.04 Reinforcing Steel 34,000 LBS 1.50 51,000
.05 Prefabricated Metal Bldg. 2,200 SF 80.00 176,000
.06 Architectural LS 20,000
Switchyard Structures LS 100,000
RESERVOIR. DAM AND WATERWAY
Reservoir
m Oearing 11 AC 4,000.00 44,000
Dam. Concrete-Faced Rockfill
.01 Diversion&: Care of Water LS 30,000
(Use of siphon to lower lake)
.02 Foundation Excavation
a. Unclassified 740 CY 20.00 15,000
b. Rock Trench 150 CY 50.00 8,000
.03 Foundation Treatment
a. Curtain Grouting 440 LF 70.00 31,000
.04 Rockfill
a. From Feature Excavation 2,500 CY 5.00 13,000
b. From Borrow -CY
.05 Concrete Facing
a. Bedding Material 940 CY 50.00 47,000
b. Concrete Face 95 CY 800.00 76,000
c. Concrete Toe 35 CY 800.00 28,000
d. Reinforcing 13,000 LBS 1.50 20,000
Waterway
Total
Cost
335,000
519,000
100,000
44,000
278,000
Xll0222.353 i\12&198 fi'VV'~ECK
r..r .-I:I'IUIA D
..
Unit Total
Item/Description Quantity Unit Price Amount Cost
332.31 Siphon Intake 295,000 ..-
.01 Diversion & Care of Water LS 5,000
.02 Excavation, (trench for pipeline)
a. Common 600 CY 10.00 6,000
b. Rock 2,500 CY 25.00 63,000
.03 Concrete cutoff wall 10 CY 1,000.00 10,000
.04 Siphon Piping, HDPE, 24" I.D.
a. Lake pipe 420 LF 150.00 63,000
b. Buried to Vacuum House 100 LF 20.00 2,000 . ~-,
.05 Backfill 2,000 CY 20.00 40,000
.06 Screen Intake LS 6,000
.07 Control Building, pre-fabricated LS 25,000
.08 Siphon, Valve and controls LS 75,000
332.32 Penstock 1,982,000
.01 Gearing 9 AC 8,000 72,000
.02 Erosion Control LS 20,000
.03 Rock Excavation 200 CY 500.00 100,000
.04 Steel Pipe Procurement, 24" I.D.
a. 3/16" plate thickness 3,500 LF 52.00 182,000
b. 1/4" plate thickness 1,550 LF 62.00 %,000
c. 3/8" plate thickness 1,650 LF 84.00 139,000
d. 1;2" plate thickness 1,180 LF 107.00 126,000
.05 Install Pipeline
a. Above Ground 4,530 LF 170.00 770,000
b. Buried 3,350 LF 48.00 161,000
.06 Supports, Anchored 83 EA 2,400.00 199,000
.07 Concrete Anchor/Thrust Blocks 9 EA 13,000.00 117,000
332.33 Water Supply Pipeline/Marine Pipeline 2,344,000
.01 Gearing -AC 8,000.00
.02 Procure and Install HOPE
a. Buried Pipeline 1,200 LF 120.00 144,000
(27" nominal dia.)
b. Marine Pipeline 18,800 LF 100.00 1,880,000
(16" nominal dia.}
c. Buried Pipeline in Intertidal Zone 5,400 LF 50.00 270,000
(16" nominal dia.)
332.34 Booster Pump and Transmission Main 923,000
.01 Civil 260,000
.02 Structural 164,000
.03 Mechanical 137,000
.04 Electrical 215,000
.OS Misc. 147,000
B-2 R. W. Beck 8,12&'98 X110222.353
\...UN:) I KU'l.. II'-''" .._....,..., • --• •· · •· ---
Unit Total
Item/Description Quantity Unit Price Amount Cost
333 TURBINES AND GENERA TORS 1,220,000
.01 Procure Turbine and Governor LS 330,000
.02 Procure Generator and Exciter LS 460,.000
.03 Procure Spherical Valve LS 65,000
.04 Install Turbine and Governor LS 75,000
.05 Install Generator and Exciter LS 75,000
.06 Install Spherical Valve LS 15..000
.07 Procure and Install300 kW Pelton 200,000
Unit
334 ACCESSORY ELECTRICAL EQUIP. 110,000 110,000
335 MISC. POWER PLANT EQUIPMENT LS 190,000
.01 Powerhouse Mechanical Systems LS 120,000
.02 Hoisting Equipment LS 70,000
336 ROADS, JETTY 299,000
.01 Marine Pier
a. Native graveVrockfill 2..000 CY 10.00 20,000
b.Sheetpiling 5,000 SF 25.00 125,000
.02 Access Road to Powerhouse
a.Oearing 0.5 AC 8,000.00 4,000
b. Permanent Road, with course 0.3 MI 500,000.00 150,000
material surface
353 SUBSTATION EQUIPMENT 930,000
.01 Powerhouse Switchyard
a. Transformer LS 150,000
b. Circuit Switcher 'LS 40,000
c. Relaying Control LS 75,000
d. Bus Work/Line Taps LS 25,000
e. Conduit Wiring LS 20,000
f. Grounding LS 20,000
.02 Tyee-Wrangell Switchyard
Modifications
a. New Bus Position LS 350,000
b. New Transformer LS 150,000
69/138-24.9 kV
.03 Wrangell Substation Modification LS 100,000
354 TOWERS AND FIXTURES
354.1 Transmission Line LS 150,000
354.2 Wrangell Feeder 4 Upgrade 315,000
.01 Feeder 4 tap LS 75,000
.02 Upgrade Feeder 4 to 24.9 kV 16 MI 15,000.00 240,000
TOTAL DIRECT CONSTRUCilON COST (!cl_1.1!1ded) $10,030,000
X110222.353 8/2SI98 R. W. Beck B-3