HomeMy WebLinkAboutWWP273536 (9)Engineers... Working Wonders With Water
CITY OF RENTON
2009 WASTEWATER LIFT STATION PRE -DESIGN
WESTVIEW ALTERNATIVES ANALYSIS
FINAL
July 2009
1218 THIRD AVENUE • SUITE 1600 - SEATTLE, WASHINGTON 98101.3032 - (206) 684-6532 - FAX (206) 903-0419
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CITY OF RENTON
2009 WASTEWATER LIFT STATION PRE -DESIGN
WESTVIEW ALTERNATIVES ANALYSIS
TABLE OF CONTENTS
1.0 INTRODUCTION........................................................
2.0 BACKGROUND..........................................................
3.0 LIFT STATION REHABILITATION ALTERNATIVES.
3.1 O&M Staff Concerns .........................................
3.2 Lift Station Rehabilitation Alternative Summary
3.2.1 Alternative 1.......................................
3.2.2 Force Main Re-routing .......................
4.0 GRAVITY SEWER ROUTE ALTERNATIVES ............
4.1 Gravity Sewer Route Alternatives Summary ....
4.1.1 Alternative 2.......................................
4.1.2 Alternative 3.......................................
5.0 COST ANALYSIS.......................................................
5.1 Easement Costs ...............................................
5.2 Total Project Costs ...........................................
5.3 Life Cycle Costs ................................................
5.4 Annual Cost Method Analysis ...........................
6.0 WESTVIEW ALTERNATIVES EVALUATION .............
7.0 RECOMMENDATIONS...............................................
8.0 REFERENCES...........................................................
APPENDIX A Preliminary Geotechnical Evaluation
APPENDIX B Cost Analysis Spreadsheets
LIST OF TABLES
Page
1
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............................................... 6
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................................................9
............................................... 9
............................................. 10
..............................................12
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..............................................16
..............................................17
..............................................17
..............................................19
Table 1 Easement Unit Costs and Requirements....................................................... 13
Table 2 Easement Costs............................................................................................. 13
Table 3 Total Project Cost Summaries (2009 Dollars) ................................................ 15
Table 4 Life Cycle Cost Summaries (2009 Dollars) ..................................................... 16
Table 5 Annual Cost Method Analysis (2009 Dollars) ................................................. 16
Table 6 Evaluation Criteria Comparison...................................................................... 18
LIST OF FIGURES
Figure 1 Lift Station Rehabilitation Layout Alternative 1 Plan ......................................... 3
Figure 2 Lift Station Rehabilitation Layout Alternative 1 Section .................................... 4
Figure 3 Gravity Sewer Route Alternatives, Sheet 1 of 2............................................... 7
Figure 4 Gravity Sewer Route Alternatives, Sheet 2 of 2............................................... 8
July 20, 2009 - FINAL
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July 20, 2009 - FINAL
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City of Renton
WESTVIEW ALTERNATIVES ANALYSIS
1.0 INTRODUCTION
The purpose of this analysis is to evaluate lift station rehabilitation alternatives and perform
a route analysis to determine if the Westview Lift Station may be abandoned and replaced
with a new gravity sewer. One lift station rehabilitation alternative and two gravity sewer
route alternatives have been evaluated to determine the service altemative for the
Westview Area.
2.0 BACKGROUND
The Westview Lift Station is a small submersible station serving 12 homes that was
constructed in 1995. The lift station includes two, 2 horsepower (hp) grinder pumps that
pump sewage north along Monterey Ave. N.E. to a manhole, which eventually leads to the
N.E. 12th St. sewer system. City of Renton (City) operation and maintenance (O&M) staff
have expressed concerns regarding operation difficulties stemming from the facility
configuration and quality of components. Alternatives for lift station rehabilitation and/or
upgrades are presented in this analysis.
The City prefers to serve customers via a gravity sewer pipeline, rather than a lift station
whenever feasible. A gravity system eliminates electricity costs for pumping and equipment
maintenance, which greatly reduces annual O&M costs. Based on survey data, conversion
to a gravity system is possible at this location following private backyards, steep slopes,
and forested, hilly terrain. Alternatives for a gravity sewer are discussed in this analysis.
3.0 LIFT STATION REHABILITATION ALTERNATIVES
An alternative for lift station rehabilitation is presented as a backup alternative if a gravity
system is not deemed feasible. The alternative presented includes minimal upgrades to the
existing lift station, as the Westview Lift Station does not require full replacement. The lift
station was constructed less than 15 years ago and structural features such as the wet well
and access ladders are still in good shape.
3.1 O&M Staff Concerns
City O&M staff have expressed the following concerns with the Westview Lift Station:
Discharge isolation (gate type) and check valves (ball type) located inside the wet
well are corroding and are effectively inaccessible.
Ball -type check valves are not seating effectively. When a check valve fails to seat,
liquid from the force main drains back into the wet well, requiring additional pumping.
July 20, 2009 - FINAL
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• Metal supports and anchors are rusting and need to be replaced with stainless steel
materials to ensure pipes, guide rails, and other components do not fall into the wet
well.
• The pump rail system is aged and pulling of the pumps is difficult.
• Electrical terminations within the junction boxes inside the wet well are corroding and
do not appear to comply with National Fire Protection Association (NFPA) 820 code.
• The lift station does not have a backup level measurement system.
• The wet well is constructed with a flat bottom, thus necessitating monthly washing
and yearly vacuum truck cleaning.
• The force main is routed behind homes making access and maintenance more
difficult.
3.2 Lift Station Rehabilitation Alternative Summary
The lift station rehabilitation alternative is presented in this section as Alternative 1. The
alternative is summarized below. A preliminary layout (plan and section) of the existing wet
well and new valve vault detailing all upgrades are shown in Figure 1 and Figure 2. An
additional alternative to re-route part of the existing force main is also discussed at the end
of this section.
3.2.1 Alternative 1
Alternative 1 includes minimum lift station upgrades to improve O&M operations.
Recommended lift station upgrades and reason for the upgrade are summarized below:
New concrete valve vault located adjacent to the wet well with new isolation (plug
type) and check valves (swing type), instrumentation connections, and sump pump
vault drain back to the wet well.
— Valves will be easily accessible in a separate vault consistent with other City lift
stations. Plug valves and swing type check valves are recommended for
sewage applications. The installation of these valves will provide better isolation
of the force main from the pump station. It is recommended to install a tap with
isolation valve (ball type) upstream and downstream of the check valve on each
discharge line for future instrumentation connection (i.e. pressure gauge). The
sump pump will serve to drain the valve vault by pumping back into the wet
well. The discharge line will be equipped with a check valve and plug valve, and
union for disassembly.
July 20, 2009 - FINAL 2
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EXISTING
GRATING (BELOW)
REPLACE AND RELOCATE
EXISTING JUNCTION BOX \\\
AND CONDUIT
SECTION
(SEE FIGURE 2)
EXISTING
ACCESS
ACCESS
LADDER
EXISTING ACCESS
LADDER (BELOW)
/ 2 HP GRINDER PUMP
(TYP OF 2)
SLOPED BOTTOM WET WELL (TYP)
EXISTING 8' SANITARY
SEWER INFLUENT
FLEXIBLE
CONNECTION (TYP)
1 1 /Y STAINLESS
STEEL DISCHARGE
PIPING (TYP) ,
fC
REPI
REL(
JUNI
CON
1YY PVC
TO WET WELL
STAINLESS
SUBMERSIBLE STEEL
TRANSMITTER/ GUIDE RAIL
LEVELTRANSDUCER SUPPORT
LLEVELSAND AS REQUIREI
EXISTING WATCH STAINLESS STEEL
OPENING (2'-0' X X-V) SUPPORT BRACKET
EXISTING LIFT
STATION WET WELL
Lo
co
N
m
Q
2
a
:1 WTI
D ELECTRIC UNION (TYP)
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TAP AND BALL VALVE FOR FUTURE
INSTRUMENTATION CONNECTION (TYP)
EXISTING 3'
DUCTILE IRON
FORCE MAIN
FLANGED
CONNECTION 4
1 1/2' X 3• m
RECESSED I
RED(TYP)
SUMP II?
ACCESS RUNGS
SUMPPUMP
NEW PRECAST
CONCRETE VALVE VAULT
Figure 1
LIFT STATION REHABILITATION LAYOUT
ALTERNATIVE 1 PLAN
2009 WASTEWATER LIFT STATION PRE -DESIGN
CITY OF RENTON
GRADE EL 239,P- EL TBD
/1K,
STAINLESS STEEL
!I PIPE SUPPORT
STAINLESS STEEL C•
CHANNEL GUIDE RAIL
PIPE SUPPORT
(TYP)
GRATING
STAINLESS STEEL
GUIDE RAIL
SUPPORT (TVP)
5'-0't
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I
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• . _ EL 223.0t (FIELD VERIM
VANES TYPICAL SECTION
Figure 2
LIFT STATION REHABILITATION LAYOUT
ALTERNATIVE 1 SECTION
2009 WASTEWATER LIFT STATION PRE -DESIGN
CITY OF RENTON
i AV+�rw//4%
r-
Replace anchors and supports with stainless steel anchors and supports.
— Stainless steel supports and anchors will have a longer life compared to other
metals in this application. Stainless steel anchors/supports will reduce the
potential for materials falling into the wet well and being sucked up by the
pumps.
Replace stainless steel discharge piping in wet well, as required.
— Discharge piping inside the wet well will require replacement based on new
discharge configuration.
Replace pump guide rail system.
— Pump guide rail system appears to be bent due to age and inadequate support
and installation. A new stainless steel guide rail system with one-piece welded
construction and additional supports should provide better durability and reduce
binding during pump extraction.
Replace junction boxes with NEMA 4X rated junction boxes located outside of the
classified ventilation area per NFPA 820.
— Per current City design standards, junction boxes shall be easily accessible
without entering the wet well.
Replace grinder pumps with similar grinder pumps.
— The existing grinder pumps are nearing their useful life and will require
replacement due to the increased cable length required for locating the new
junction box outside the wet well. Cable will be routed below grade to new
junction box.
Relocate float levels and use as backup level measurement system.
— The floats will require replacement due to the increased cable length required
for locating the junction box outside the wet well. Cable will be routed below
grade to the new junction box. Based on record drawings, it is assumed that the
existing control panel can accommodate backup controls.
Add submersible transmitter/level transducer and use as primary level measurement
system.
— Consistent with other City lift stations, wet well level will be measured using a
transducer. Based on record drawings, it is assumed that the existing control
panel can accommodate the new signals from the transducer for primary level
measurement and pump control.
July 20, 2009 - FINAL 5
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Modify wet well bottom to create slope as existing conditions allow.
— A sloped wet well bottom may reduce frequency of wet well cleaning and
vactodng. A minimum 45-degree slope is recommended with a preferred 60-
degree slope; however, existing wet well volume will dictate degree of slope.
Alternative 1 presents a low impact, low cost solution to upgrade the Westview Lift Station
in comparison to a full station replacement. The proposed upgrades may require minimal
permitting. Additionally, construction activity and impact to the public will be minor.
Alternative 1 will continue to require O&M of the lift station; however, vactor cleaning of the
wet well should be less frequent compared to current operations. This alternative is
estimated to extend the facility useful life until 2029 or 20 years.
The current lift station serves 12 homes in the Westview Area. City staff estimate up to ten
(10) additional new homes for a total of 22 within the service area connecting to the existing
lift station. Based on design flows from record drawings, it is estimated that an additional
ten (10) homes will reduce the lift station storage capacity from its initial two (2) hour design
storage (in -line), to approximately one (1) hour. The City shall determine if one (1) hour of
storage for this lift station is acceptable; otherwise, a new, larger wet well with be required.
Pump horsepower will not be affected by the increase in required pumping flow; however, a
larger impeller diameter will be required. The wet well is sized sufficiently large enough that
pump motor starts will also not be affected by the increase in design flow. Fluid velocity in
the force main will increase, which will produce better cleaning capability.
3.2.2 Force Main Re-routing
Alternative 1 could be enhanced to include extending a new force main up Monterey
Avenue N.E. to N.E. 12th Street rather than behind neighborhood houses. The modification
of the existing force main includes re-routing approximately 250 feet of 3-inch diameter
(ductile iron) force main directly up Monterey Avenue N.E. to a manhole located in N.E.
12th Street to simplify maintenance and access of the force main for O&M staff. Based on
pump performance curves in record drawings, the pump horsepower will not be affected by
the new discharge location; however, a larger impeller diameter on the new pumps will be
required to accommodate the additional head loss. Construction of the new force main may
disrupt access to and from the Westview neighborhood on Monterey Avenue N.E., as well
as require closure of a section of lane on N.E. 12th Street. The construction may be
performed prior to rehabilitation of the lift station; however, new pumps with higher head
capability shall be installed prior to final connection to the existing force main.
4.0 GRAVITY SEWER ROUTE ALTERNATIVES
Two gravity sewer alignments are presented in this section. For comparison with Alternative
1 in this analysis, the sewer route alignments are presented as Alternative 2 and Alternative
3. The proposed alignment of each sewer route is depicted in Figure 3 and continued on
Figure 4. The alternatives are summarized below.
July 20, 2009 - FINAL 6
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PROPERTY lAES
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NOTES:
H=ZOrtu DATUM: KAO 93/9140 MONUEAR ON NE. 1214 ST. PER TM
RAT Of WESTMER. RECP509280404(VOL 174-PAGE 52M)
VERNAL, DATIVE. HOD CITY OF RFNTOM BENCH MARK NO. RDNT57
BRASS DISK N TOP OF COML MDN AT THE MTX OF
ME I Th ST. AND MMODS AVE.
ELEVATION-324,432-NNAW
AL DISTANCES 900 ARE GROUND DISTANGS HMaEs OYHOMS Norm.
THE LOCA71ON AND OCOMPT10N OF ALL SUREY MARKERS 910■N ME FOR ARE BASED ON FFL^.
OBSERVATONS TAIGN M MAY 2M. UNLESS OTHERWISE WOCAIED.
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ALL MONUMENTS —TED AS FOOD WALE RECOYM OKNK' THE CORSE OF INS SURREY AT
THE DATE SHOWN N M SUIVEYQF6 CERTF1CAT, UNLESS OTIEIWSC NOTED.
Figure 3
GRAVITY SEWER ROUTE ALTERNATIVES, SHEET 1 OF 2
2009 WASTEWATER LIFT STATION PRE -DESIGN
CITY OF RENTON
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•
SEE SHEET 1
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ALL 067ACB 910M ARE OIORD 015TANCES UNLESS OTIERMSE IOTEO
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THE LOCATION AOERN OF ALL "VEY MARKERS WIN HEREON ARE RASM ON FEIt
CASERVATCNS TAKEN M MY 2(DL. UNLESS OTIERVISE V DCATED.
WORK POFON11D N COMANC110N W1N TaS SLOWY UIUTHEZED TFOUDNIG EUN EN` AND
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MAOFACRKR< SPEEr1CA7ONS PER WAG 332-130-M, (B) EELD TRAVO� EXCEEDING
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THIS STAKY WAS PERFORM WTINODE-IT
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COITRACIDR/904MIS SHALL VORFY DACT ME AND LOCATION PROR TO CONGTILCTION.
CAL FOR LOCATE: UWTY LDCATON SERA¢: I-IOD-425-5555
AL MONUAOs RpG1ED AS FORD MORE REDDENED W" TIC COURSE OrR M SKY AT
11E wL 9 N TM sLwoLm S CERw1UIR LMESS OIHINwY mi.
• PLASTIC CAP STWEAYPM 1LS. 033130
NOTES:
UNLESS OTHERVFSE STATED.
• TREES ASSUMED TO BE DEMOLISHED
DIRECTION OF FLOW
l P.i. /lam
HOMEOWNER of
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Figure 4
GRAVITY SEWER ROUTE ALTERNATIVES, SHEET 2 OF 2
2009 WASTEWATER LIFT STATION PRE -DESIGN
CITY OF RENTON
4.1 Gravity Sewer Route Alternatives Summary
4.1.1 Alternative 2
Alternative 2 includes a pipeline routed from the existing lift station wet well to a series of
manholes before discharging into existing Manhole No. 5. The pipeline is assumed to be 8-
inch diameter, polyvinyl chloride (PVC) gravity sewer pipe in accordance with American
Society for Testing and Materials (ASTM) D 3034. The gravity sewer pipeline is estimated
to be 780 feet long with 3 intermediate manholes.
The sewer alignment for Alternative 2 follows along high, flat terrain for most of the route
(see Figures 3 and 4). The pipeline will begin at the existing lift station wet well and is
routed just north of an existing 8-inch thick concrete retaining wall. Trench depths are
estimated to be a maximum of 9 feet deep at the pipelines beginning. This routing will need
to be potholed to confirm that there is no interference with the retaining wall and an
easement may be required with the adjacent homeowner for constructability of the pipeline.
If determined not feasible, alternate routing will be required with the potential addition of
another manhole. This section of land in which approximately 80 feet of pipeline is routed is
owned by the Homeowner's Association (HOA). Based on conversations with City staff, it is
assumed that an easement for this property will be easily obtainable.
Beyond the retaining wall, the pipeline enters private property where approximately a third
of the pipeline is routed directly through Homeowner A's backyard (see Figure 3). To
eliminate manholes in the backyard, the pipeline can be longitudinally bent (deflected at the
joints) to accommodate a sweeping S-shaped alignment. To account for construction errors
where the pipe is completely inserted together, a minimum bend radius of 220 feet, or twice
the manufacturer's minimum bend radius, is recommended.
Homeowner A currently uses a 48-inch diameter manhole located in the northwest corner of
the backyard, to which their sewage flows and then is pumped out to the main gravity
system on N.E. 12th Street. It is assumed that Homeowner A will tie into the newly
constructed gravity sewer line near this location and abandon their individual pump and
force main system.
Construction of the pipeline through Homeowner A's backyard will require small excavation
equipment and can be installed with minimum 3-foot cover. A 10-foot clear width through
the backyard is estimated to provide adequate clearance for equipment and pipeline
installation. Construction access will be through the homeowner's driveway. This alternative
will require extensive landscaping rehabilitation and possible reconstruction or construction
of modular block retaining walls for hillside stability as the alignment traverses along the top
of a steep backyard slope (approximately 60 percent slope). Due to the steep slope
adjacent to the pipeline, a critical area permit will be required along with a study prepared
by a geotechnical engineer to determine construction feasibility. Existing underground
electrical, water, and storm drainage utilities may require relocation. An easement in
Homeowner's A property will be required.
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Once the pipeline is routed outside of Homeowner A's property line, the pipeline will enter
Homeowner B's property line as it is routed towards existing Manhole No. 6 into N.E. 12th
Street Right -of -Way. A sloped hillside (approximately 20 percent slope) and open cut trench
depths of.up to 10 feet will increase construction complexity. Overhead power lines may
require temporary relocation during construction. This section of pipeline is anticipated to
require significant clearing, grubbing, and grading. A 20-foot clear width through this area is
estimated to provide adequate safety clearance for equipment and pipeline installation. One
34-inch diameter Fir tree may require removal for pipeline installation.
The remaining section of pipeline will parallel an existing sewer pipeline down an
approximate 25 percent -sloped grassy hill still within Homeowner B's property, but also
within N.E. 12th Street Right -of -Way. Open cut trench depths are estimated to be a
maximum of 10 feet. Two 20-inch diameter Cotton Wood trees may require removal for
pipeline installation. An easement in Homeowner B's property will be required. Construction
and access is not anticipated to cause any difficulties in this reach of pipe; however, the
final connection to existing Manhole No. 5 is within close proximity to Interstate 405 Right of
Way (1-405 ROW). Construction is estimated to be approximately 300 feet from the
centerline of 1-405. A permanent and/or construction easement may be required.
Based on the investigations conducted by HWA Geosciences Inc. (see Appendix A), it is
anticipated that trenching will be within recessional outwash sand materials. It is
recommended that short sections of trench be excavated, line installed, and backfilled prior
to opening the next section. The pipeline can be installed using trench boxes to minimize
trench width and soil disturbance. Groundwater is not anticipated to be of concern for this
routing; however, should this alternative be selected, surface soils and groundwater
conditions will need to be analyzed to determine potential impact on the pipeline.
The City's current operation standard is to have easy truck access to at least every other
manhole. Access to the first manhole approximately 100 feet west of the existing lift station
may be provided via Homeowner A's driveway. A separate easement for access to this
manhole will be required (additional easement cost not included in this analysis). The
manhole next to N.E. 12th Street is easily accessible by truck. The existing manhole to
which the new pipeline will connect is accessible by foot from N.E. 12th Street.
Alternative 2 is estimated to be a high capital cost alternative particularly due to
construction complexity, existing terrain uncertainties, and easement costs. Advantages of
conversion to a gravity system include minimal O&M costs for the life of the pipeline. The
design life of a gravity sewer is estimated to be 80 years, or four times that of lift station
mechanical and electrical equipment.
4.1.2 Alternative 3
Alternative 3 includes a pipeline routed from the same starting and ending locations as
Alternative 2; however, it is estimated that only 2 intermediate manholes will be required for
this alignment. The pipeline is assumed to be 8-inch diameter, PVC gravity sewer pipe in
accordance with ASTM D 3034. The gravity sewer pipeline is estimated to be 720 feet long.
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The sewer alignment for Alternative 3 is similar to that of Alternative 2 for approximately the
first 100 feet, but then follows what may be an old access road, downhill roughly 12 feet
wide. The pipeline is routed at the base of a steep bank in Homeowner A's backyard (see
Figure 3). The pipeline then follows an arced path around a bowl -shaped (approximate 35
percent slope) forested area entering Homeowner B's property to existing Manhole No. 5.
The pipeline can be longitudinally bent similar to as discussed in Alternative 2 to
accommodate a sweeping S-shaped alignment. An easement in both homeowners'
property will be required. It is anticipated that a critical area permit will be required due to
the steep slopes associated with the pipeline alignment. Additional geotechnical evaluation
is needed to determine construction feasibility.
Construction of the pipeline will require large cuts to be made into the sloped hillside for
construction equipment access and pipeline installation. Excavation depths are estimated to
be an average of 9 feet deep. Approximately 15 trees of diameter 6-inch and larger will
need to be removed for the proposed alignment. A 20-foot clear width through the forested
area is estimated to provide adequate safety clearance for equipment and pipeline
installation. Extensive clearing and grubbing will be required, as well as landscape
rehabilitation within Homeowner A's property. Existing underground electrical, water, and
storm drainage utilities may require relocation within Homeowner A's property. Overhead
power lines crossing through Homeowner B's property may require temporary relocation
during construction. Similar to Alternative 2, a permanent and/or construction easement
may be required based on 1-405 ROW margins.
Construction access will be near existing Manhole No. 6 and construction activities will
begin at existing Manhole No. 5 and work back up the proposed alignment to minimize or
eliminate equipment access through Homeowner A's driveway. Unlike Alternative 2, it may
not be feasible for Homeowner A to tie into the new gravity sewer given their existing
sewage discharge location and the steep bank (approximately 60 percent slope) between
the discharge and new pipeline. Options for Homeowner A to connect to the new gravity
pipeline will require further investigation if Alternative 3 is selected.
Similar to Alternative 2, it is recommended that short sections of trench be excavated, line
installed, and backfilled prior to opening the next section. The pipeline can be installed
using trench boxes to minimize trench width and soil disturbance. Groundwater may be
encountered in the forested area of the pipeline. If this alternative is selected; surface soils
and groundwater conditions will need to be analyzed to determine potential impact on the
pipeline.
In accordance with the City's Standard, the only manhole with truck access for Alternative 3
is the first manhole approximately 100 feet west of the existing lift station. Similar to
Alternative 2, an easement for Homeowner A's driveway will be required to access this
manhole (additional easement cost not included in this analysis). The final two manholes
(one new and existing Manhole No. 5) at the end of the alignment will be accessible by foot
from N.E. 12th Street.
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Alternative 3 is estimated to be a high capital cost alternative particularly due to
construction complexity, existing terrain uncertainties, and easement costs. However, this
alternative is estimated to be less costly than Alternative 2 based on a smaller amount of
uncertainty associated with pipeline alignment and slope stabilization requirements.
Advantages of this alternative are similar to those discussed in Alternative 2.
5.0 COST ANALYSIS
The cost analysis for the lift station rehabilitation and sewer route alternatives include total
estimated construction and project costs and 25-year life cycle costs (expected accuracy
range of +50 percent to -30 percent). Each alternative is also evaluated by the annual cost
method described at the end of this section. See Appendix B for detailed cost estimate
spreadsheets.
5.1 Easement Costs
Easement costs are required for Alternatives 2 and 3. Both alternatives will require an
easement from Homeowner A, Homeowner B, and the HOA parcel. It is not anticipated that
an easement cost will be required for rehabilitation of the lift station for Alternative 1. The
easement costs are based on 25 percent of the appraised land value on a dollar per square
foot basis multiplied by the required easement area, as recommended by City Staff. A
summary of this method to determine a unit cost and the required square footage for each
easement is summarized in Table 1. Easement costs for the three alternatives are
summarized in Table 2. As stated earlier, it is assumed there is no easement cost for
Alternative 1. Easement costs for Alternatives 2 and 3 are estimated to be $10,000 and
$12,000, respectively. These costs have the potential to vary based on developed and
undeveloped areas and should be given further analysis if a gravity sewer alternative is
chosen for pre -design.
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Table 1 Easement Unit Costs and Requirements
2009 Wastewater Lift Station Pre -Design
City of Renton
Alternative 1
Alternative 2
Alternative 3
Appraised Approx. 25 Percent of
Unit
Easement
Easement
Easement
Land Lot Size Appraised
Cost
Requirement
Requirement
Requirement
Easement Required Value(') (ft2) Land Value
($/ft2)
(ft2)
(ft)(3)
(ft)(3)
Homeowner A $189,000 64,000 $47,300
0.74
N/A
3,100
6,000
Homeowner B $211,000 54,000 $52,800
0.98
N/A
6,700
6,000
HOA Parcel N/A N/A N/A
0.86(2)
N/A
800
800
Notes:
(1) Appraised November 2008 through King County Assessors (KCA) Record Search.
(2) Assumes average unit cost of Homeowner A and Homeowner B.
(3) Assumes 10-foot easement width in open areas and 20-foot easement width in forested areas.
Table 2 Easement Costs
2009 Wastewater Lift Station Pre -Design
City of Renton
Alternative Homeowner A
Homeowner B
HOA Parcel
Total Easement Cost (2)
Alternative 1 - Lift Station Rehabilitation N/A
N/A
N/A
$0
Alternative 2 - Gravity Sewer Route $2,300(')
$6,600(')
$700(')
$10,000
Alternative 3 - Gravity Sewer Route $4,500(')
$5,900(')
$700(')
$12,000
Notes:
(1) Calculated by multiplying the unit cost by the required easement area summarized in Table 1.
(2) Rounded up to nearest thousand dollars.
5.2 Total Project Costs
The construction costs for each alternative were calculated assuming the following:
• Contingency = 20 percent for Alternative 1.
• Contingency = 30 percent for Alternatives 2 and 3.
• Contractor overhead, profit, and risk = 10 percent.
• Sales Tax = 9.5 percent.
• General conditions = 5 percent.
• Costs associated with environmental and permitting measures not included.
• The cost estimate herein is based on our perception of current conditions at the project
location. This estimate reflects our professional opinion of accurate costs at this time
and is subject to change as the project design matures. Carollo Engineers have no
control over variances in the cost of labor, materials, equipment; nor services provided
by others, contractor's means and methods of executing the work or of determining
prices, competitive bidding or market conditions, practices or bidding strategies.
Carollo Engineers cannot and does not warrant or guarantee that proposals, bids or
actual construction costs will not vary from the costs presented as shown.
The total project cost includes an additional 30 percent of the construction cost to account for
all allied costs (i.e. construction and engineering) in addition to the easement costs
discussed earlier. The total project cost for each alternative is shown in Table 3. The total
project cost for Alternatives 1, 2, and 3 is $110,000, $460,000, and $410,000, respectively.
Alternative 1 could be enhanced to include extending a new force main up Monterey Avenue
N.E. to N.E. 12th Street rather than behind neighborhood houses. This would increase
construction costs an additional $40,000 ($52,000 total project cost). The cost includes re-
routing of approximately 250 feet of 3-inch diameter (ductile iron) force main directly up
Monterey Avenue N.E. to a manhole located in N.E. 12th Street. This effort could be
completed by City O&M staff prior to the lift station upgrade as long as the final connection to
the existing force main is made after the new pumps are installed.
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Table 3 Total Project Cost Summaries (2009 Dollars)
2009 Wastewater Lift Station Pre -Design
City of Renton
Alternative 1 -
Alternative 2 -
Alternative 3 -
Lift Station
Gravity Sewer
Gravity Sewer
Estimated Costs Rehabilitation
Route
Route
Construction(') $80,000
$340,000
$300,000
Allied (30 percent) $24,000
$102,000
$90,000
Easement (Table 1) $0
$10,000
$12,000
Total Project Cost(') $110,000
$460,000
$410,000
Notes:
(1) Rounded up to nearest ten thousand dollars.
5.3 Life Cycle Costs
Life cycle costs for each alternative were calculated over a 25-year period. The following
assumptions were made in calculating the costs for all alternatives:
• Interest Rate = 5 percent.
• O&M staff hourly rate = $40 per hour.
• Rate of inflation = 3 percent per year.
The following assumptions were made for calculating the life cycle costs for Alternative 1:
• Mechanical, electrical, and instrumentation equipment life = 20 years.
Assumes control panel and telemetry unit replacement in years 2014 and 2024
(based on installation in 1995).
• Electrical power costs = $0.06/kW-hr.
• Grinder pump efficiency = 25 percent.
• Lift station operation = 8 hours per day.
• Routine maintenance and wet well washing = two O&M staff at 8 hours per month.
• Vactor cleaning reduced to four times per year.
• Miscellaneous yearly equipment replacement = 1 percent of rehabilitation capital cost.
• Structural modifications to concrete wet well in 25-year life span not included.
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The following assumptions were made for calculating the life cycle costs for Alternatives 2
and 3:
Routine maintenance = two O&M staff at 16 hours each per year.
The 25-year life cycle cost for each alternative is shown in Table 4 along with the total
project cost for reference. Lift station rehabilitation Alternative 1 is roughly a quarter of the
total project cost of the other two alternatives. In a 25-year life cycle cost analysis,
Alternative 1 is still lower compared to gravity sewer Alternatives 2 and 3. The 25-year life
cycle cost for Alternatives 1, 2, and 3 are $340,000, $490,000, and $440,000, respectively.
Table 4 Life Cycle Cost Summaries (2009 Dollars)
2009 Wastewater Lift Station Pre -Design
Citv of Renton
Alternative 1 -
Alternative 2 -
Alternative 3 -
Lift Station
Gravity Sewer
Gravity Sewer
Cost Rehabilitation
Route
Route
Total Project Cost $110,000
$460,000
$410,000
25-Year Life Cycle Cost $340,000
$490,000
$440,000
5.4 Annual Cost Method Analysis
The annual cost method (also called the annual return method or capital recovery method) is
used to compare alternatives with unequal lives. This method assumes that each alternative
will be replaced by an identical twin at the end of its useful life. The alternatives are ranked
by calculating an equivalent uniform annual cost (EUAC). Annual O&M costs are based on
the same assumptions discussed previously for the life cycle cost analysis. The EUAC for
each altemabve is listed in Table 5.
Table 5 Annual Cost Method Analysis (2009 Dollars)
2009 Wastewater Lift Station Pre -Design
City of Renton
Alternative 1 - Alternative 2 -
Alternative 3 -
Lift Station Gravity Sewer
Gravity Sewer
Rehabilitation Route
Route
Design Life 20 80(2)
80(2)
Total Project Cost $110,000 $460,000
$410,000
Annual Estimated O&M Cost $5,700 $1,300
$1,300
EUAC(') $15,000 $25,000
$23,000
Notes:
(1) Interest rate assumed 5 percent.
(2) Based on City of Renton Long -Range Wastewater Management Plan, Planning
Considerations and Design Criteria, Review Draft January 2009, Carollo Engineers.
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Lift station rehabilitation Alternative 1 yields the lowest estimated EUAC at $15,000;
however, the EUAC for gravity sewer Alternatives 2 and 3 is only slightly higher at $25,000
and $23,000, respectively.
6.0 WESTVIEW ALTERNATIVES EVALUATION
The alternatives discussed for lift station rehabilitation and gravity sewer conversion were
further compared using qualitative ranking criteria of positive (+), neutral (0), or negative (-)
for the evaluation criteria (listed in alphabetical order) described below:
• City Preference: the perceived preference by City staff.
• Cost: includes three costs for analysis.
— Total project cost.
— 25-year life cycle cost.
— Equivalent uniform annual cost.
• Environmental/Permitting: number of required permits and environmental impacts.
• Operational Complexity: technical and physical complexity of the alternative. Ease of
operation and maintenance.
• Public Opinion: the anticipated public opinion.
• System Complexity: technical and physical complexity of the alternative. Ease of
construction. Absence of unknown potential conflicts.
• Use of Existing Assets: potential for existing facilities to be used.
The rankings are shown in the summary comparison in Table 6. Based on the evaluation
criteria previously discussed, Alternative 1 is ranked as the most desirable among the three
alternatives.
7.0 RECOMMENDATIONS
Based on the investigations performed in this analysis, Alternative 1 is recommended for
implementation at the Westview Lift Station site. Alternative 1 ranked the highest among the
evaluation criteria, as well as having the lowest overall cost with respect to total project cost,
25-year life cycle cost, and equivalent uniform annual cost. This alternative will have the
lowest construction impact on the Westview Area and can be implemented much sooner
than the gravity sewer alternatives. It is recommended that the City select Alternative 1 for
pre -design.
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Table 6 Evaluation Criteria Comparison
2009 Wastewater Lift Station Pre -Design
City of Renton
Westview Lift Station Site Alternative
Criteria
Alternative 1 - Lift Station
Alternative 2 - Gravity
Alternative 3 - Gravity
Rehabilitation
Sewer Route
Sewer Route
1)
City Preference -1
+1
+1
2)
Cost --
--
--
a) Total Project Cost +1
-1
-1
b) 25-Year Life Cycle Cost 0
-1
-1
c) Equivalent Uniform Annual Cost +1
0
0
3)
Environmental/Permitting 0
-1
-1
4)
Operational Complexity -1
+1
+1
5)
Public Opinion 0
-1
0
6)
System Complexity +1
-1
0
7)
Use of Existing Assets 0
0
0
SCORE +1
-3
-1
RANK 1
3
2
Notes:
(1)
Ranking:
" +1 " connotes: positive, more, or more desirable attributes
" -1 " connotes: negative, fewer, or less desirable attributes
" 0 " connotes: neutral determination
8.0 REFERENCES
Carollo Engineers. January 2009. City of Renton Long -Range Wastewater Management
Plan, Planning Considerations and Design Criteria, Review Draft.
City of Renton. 2008. Renton Municipal Code. Title IV Development Regulations, Chapter 6
Street and Utility Standards.
HWA Geosciences Inc. July 9, 2009. Preliminary Geotechnical Evaluation, Task 1.
Westview Lift Station, Renton, Washington.
Uni-Bell PVC Pipe Association. August 2001. Handbook of PVC Pipe, Design and
Construction.
Washington State Department of Ecology. August 2008. Criteria for Sewage Works Design.
July 20, 2009 - FINAL 19
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APPENDIX A
PRELIMINARY GEOTECHNICAL EVALUATION
rm
HWA�GEOSCIENCES! INC.�r�? ��t�,�,r, �r��,,,,,�,�r �, Inspection �E«;,r
Engineering X g) P S
July 09, 2009
HWA Project No. 2009-05 8-2 1 /Task 1
Carollo Engineers
1218 3rd Avenue, Suite 1600
Seattle, Washington 98101
Attention: Ms. Lara Kammereck, P.E.
SUBJECT: PRELIMINARY GEOTECHNICAL EVALUATION
Task 1. Westview Lift Station
Renton, Washington
Dear Ms. Kammereck;
As authorized in an Agreement for Professional Services, dated April 24, 2009, HWA
GeoSciences Inc. (HWA) completed a preliminary geotechnical evaluation for the proposed
Westview Lift Station improvements, as part of the 2009 Wastewater Lift Station Pre -Design
Contract that Carollo Engineers (Carollo) has entered into with the City of Renton. Task 1 of
three tasks authorized by the Agreement for Professional Services is reported herein, with the
remaining two submitted under separate cover and dealing with the Lake Washington Lift
Station (Task 2.) and the East Renton Lift Station (Task 3.).
In general conformance with the scope of work, described for Task 1 of our Agreement for
Professional Services with Carollo, this report presents our preliminary geotechnical evaluation
related to pre -design efforts for the subject facility.
PROJECT DESCRIPTION
We understand that the Westview Lift Station is a small station that presently serves only
12 homes from its location near the south end of Monterey Avenue NE. It was constructed in
1995 and is currently in need of rehabilitation and upgrading. In addition to evaluation of
alternatives for station upgrades, replacement of the lift station with a gravity line, extending
northwesterly to an existing manhole on the alignment of NE 121h Street, is part of the pre -design
task. The potential gravity sewer alignment alternatives entail of the order of 700 to 800 feet of
new sewer line and a number of new manhole structures between the lift station site and either of
two available tie-in manholes.
The project location is indicated on the Vicinity Map, Figure 1, attached. Figure 2, Site and
Potential Sewer Alignment Plan, shows the lift station location and two possible 19730 - 64th Avenue W.
alternative gravity sewer alignments (Alternatives 2 and 3) along with site suite 200
Lynnwood, WA 98036.5957
Tel: 425.774.0106
Fax: 425.774.2714
www.hwageo.com
July 09, 2009
HWA Project No. 2009-05 8-2 1 /Task 1
topography, which was developed by Carollo through survey of the immediate site area.
SITE CONDITIONS
The subject sewer lift station is situated on the west side of Monterey Avenue NE, at the entrance
to a cul-de-sac, which is the local terminus of this neighborhood roadway. Presently, the 3-inch
forcemain from this station extends northward along Monterey Avenue NE and takes a couple of
jogs before terminating in a manhole comprising part of another system and lying south of
NE 121h Street east of its intersection with Monterey. From that manhole, it appears that gravity
flow occurs to another manhole existing Within NE 12th Street. We understand that this latter
manhole is designated MH417 and sewer flow from here proceeds west successively through
manholes MH#7, MH#6 and MH#5. Manhole MH#6 lies at the top of a steep slope and the local
western terminus of NE 121h Street; with MH#5 lying some 250 feet horizontal distance down
slope and approximately 60 feet lower in elevation, based on plans and topographic mapping
provided by Carollo. We understood initially that either of these manholes represent points at
which a new replacement gravity sewer line would terminate. However, the alternatives
illustrated on Figure 2, suggest that a tie-in at MH#6 is probably not viable from a gradient
perspective, and it appears that Alternative 2 includes a new manhole at the top of the slope, near
MH#6, and a new segment of line almost parallel to the existing sanitary line and extending to
another new manhole beside MH#5. Alternative 3 alignment will also tie-in to this new manhole
adjoining MH#5 before the final connection with it.
From the topographic mapping provided by Carollo (see Figure 2), it is apparent that the ground
elevation at the existing lift station is approximately 239 feet, which is approximately the same
as the ground elevation at the rim of MH#6. Between the two locations, both of which lie
roughly on the crest of the steep slope that descends from this localized height of land, the
ground elevation along the slope crest appears to vary between about 232 and 234 feet elevation.
Alternative 2 would approximately parallel the slope crest in order to remain as far removed as
possible from the existing residential developments that exist along this upland perimeter area.
The other alignment alternative, Alternative 3, would descend the slope transversely,. in part
following what appears to be an old pioneer trail that traverses a part of the slope, and terminate
in MH#5 whose rim lies at about elevation 180 feet. Clearly, grade differentials for the
Alternative 2 alignment appear to be challenging in respect to development of suitable gravity
flow conditions to MH#6, and has likely prompted inclusion of a new manhole nearby, as
indicated on Figure 2. The Alternative 3 alignment has no potential constraints in this regard.
The slope profile within the vicinity of the two alignment alternatives is variable over the area of
consideration. Random cross -sections (A -A through D-D), which are shown on Figure 3
indicate that the upper section of the slope below the crest is steepest and lies at a gradient of
about 1.5 to 1.7H:1 V (about 60 to 67%), or approximately 30 to 34 degrees from the horizontal.
Below the upper steep crest, the slope is flatter and variable within the area of the survey, as
evident from the contours on Figure 2 and the random cross -sections displayed on Figure 3. In
general, the slope surface in the area of consideration is well treed and vegetated, with the
Final Letter Report Task 1 2 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. 2009-058-21/Task 1
exception of the existing sewer line alignment westward along NE 121h Street and its right of way
extension below the slope crest. This sloping section of right-of-way is also occupied by a
power transmission line and surface vegetation is limited to grasses and small shrubs.
Other site features that have a bearing on the alignment selection include several retaining wall
elements, the first of which comprises a cast -in -place concrete wall that extends both west and
south in an L-shape configuration from the lift station site. This wall supports the adjoining
ground of the lot immediately to the north and the cul-de-sac to the east, as indicated on Figure 2.
The ground elevation above the wall is roughly 239 feet and below the wall it is about 234 feet; a
vertical difference of 5 feet. The lower area defined by the wall appears to be a stormwater
management feature that was developed locally some time in the past. Of necessity, either of the
replacement gravity line alternatives will have to traverse the area north of and immediately
behind the wall, as indicated in Figure 2. Since the concrete wall construction details are
unknown at this time, there is a possibility that some structural elements associated with the wall
design and/or construction could exist in this area and could present and impediment to either of
the line alternatives. Another retaining wall that is part of previous residential landscaping and
grading work is present on one of the lots in the approximate central section of Alternative 2,
whose alignment will have to traverse up gradient or east of this modular block wall. As
indicated on Figure 2, the Alternative 2 alignment is close to the wall and it is not known
whether there are any supports or structural elements associated with the wall that may exist in
this alignment location. It is possible that there may be some support system that could be
adversely impacted by installation of a sewer line in such close proximity to the wall. The
design details of the modular block wall are also unknown and its adequacy for support of the
soils in this localized area is also a consideration in our view. Lastly, a small, "14-inch concrete
wall", is shown on Figure 2 about 50 feet north of the modular block wall. This small wall also
appears to be largely associated with residential landscaping activity and will have to be removed
as the Alternative 2 alignment conflicts with it. Removal should not be problematic, however, as
the wall appears to be associated largely with a planter in this area of the alignment, but will
represent a restoration consideration.
Although HWA's reconnaissance of the slope area and general alignments of Alternatives 2
and 3 was brief and limited, we did not see any immediately apparent evidence of slope
instability at this time. Though the upper slope section is steep and is retained by walls in
specific locations, as indicated above, there was no evidence of distress associated with recent or
incipient soil movements. There also were no significant indications that surficial runoff and
erosion instability are presently a problem on this area of the slope.
GEOLOGY
According to the Geologic Map of King County, Washington, by Derek P. Booth and Aaron P.
Wisher (Booth et al, 2006), a portion of which is reproduced on Figure 4, the site is underlain by
glacial recessional outwash soils (Qvr on the map) consisting of silty sand with gravel deposited
from the receding Vashon glacial ice sheet. This soil has not been consolidated by the weight of
Final Letter Report Task 1 3 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. 2009-058-21/Task 1
glacial ice and is typically medium dense in nature. We expect that the existing lift station and
all of the Alternative 2 alignment are underlain by this deposit. However, we also expect that
this deposit overlies Vashon glacial till at depth, which is a heterogeneous mixture of silt, sand
and gravel, with cobbles and boulders. The glacial till has been over -ridden by glacial ice and is
very dense and concrete -like as consequence, in its un-weathered state. When exposed in natural
slopes, however, the upper 3 to 5 feet is commonly weathered. As evident from the site location
(WV) indicated for Westview on Figure 4, it is possible that some portion of the lower slope that
is traversed by Alternative 3 may be underlain by glacial till at surface or within the probable
depth interval of the sewer line.
REVIEW OF EXISTING DATA
For the purposes of this assessment, HWA also reviewed existing lift station as -built and design
drawings, and subsurface data derived from previously conducted geotechnical investigations
within the local area, as referenced below:
Tract "A ", Detention Pond Notes and Details, Westview Plat; Sanitary Sewer Plan and Profile,
Westview Plat; and Pump Station Plan, Westview Plat.
Preliminary Geotechnical Report, Edmonds Avenue Site, Edmonds Avenue NE and Sunset
Boulevard NE, Renton, Washington, consultant report prepared for Cambridge Homes (Terra
Associates, Inc., 2000).
A number of explorations have been conducted in the general area east of the site (Edmonds
Avenue NE) in the past for proposed residential developments. The logs of the subsurface
explorations considered pertinent to this assessment were reviewed, but since they are somewhat
distant from the site are not included herein. Nevertheless, they do provide some indication of
soil conditions within the mapped geologic units identified on Figure 4, and probable ground
water conditions that may exist on and in close proximity to the lift station site.
SUBSURFACE CONDITIONS
Review of the exploration data, presented in the report referenced above, indicates that in general
the area of the existing lift station and the two sewer alignment alternatives is most likely
underlain by a sequence of recessional outwash, comprised of sand to sand with silt and
occasional gravel particles. However, it is anticipated that in the vicinity of the lift station and
along the Alternative 2 alignment, there could be significant amounts of surficial and
near -surface fill that may have been derived from construction of the local streets, services and
the residential developments. Additionally, the surficial layer may comprise significant amounts
of topsoil and/or organics, particularly along the Alternative 3 alignment where a significant
amount of forest duff may have accumulated on the slope surface. The recessional outwash and
any fill are anticipated to be loose to medium dense in terms of relative density.
As indicated previously, glacial till may exist at lower reaches of the slope and may be
encountered within the depth of a gravity sewer constructed along the alignment of Alternative 3.
Final Letter Report Task 1 4 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. ,2009-058-21/Task 1
Except for the upper 3 to 5 feet of soils along the Alternative 3 alignment, the soils are
anticipated to be medium dense to dense to very dense if till is encountered. The upper
weathered zone of slope soils are anticipated to be loose to medium dense, consistent with
weathering effects.
Test pit explorations within the upper recessional outwash (Terra Associates, Inc., 2000)
revealed no ground water seepage within depth intervals from 8 to 12 feet below grade.
However, these observations were made in late summer when the seasonal ground water
conditions would be at their lowest levels, and water conditions could be higher during
seasonally wet periods. Additionally, if glacial till is present it can serve as a perching layer and
ground water may be encountered at or near its surface contact with overlying more pervious
recessional outwash. In general, however, we do not expect problems with ground water
presence and seepage into trench excavations in the uplands areas associated with both options.
Along the lower reaches of Alternative 3, ground water may be present within the trench
excavation if it is based in or near the outwash-till contact. Some ground water management
may be required if this situation is encountered in open trench excavations.
CONCLUSIONS AND RECOMMENDATIONS
In view of existing topographic and subsurface conditions at the Westview Lift Station site, it is
our opinion that improvements may take the form of either modification of the existing station,
or replacement with a new gravity line including a number of new manhole structures.
Either Alternative 2 or Alternative 3, as indicated on Figure 2, is considered suitable for
construction from a geotechnical perspective. However, Alternative 2, in addition to being
roughly 60 feet longer, is considered to be somewhat more vulnerable to potential slope
instability that might occur in the upper steeper section of the existing slope below the existing
slope crest. Since the Alternative 2 alignment lies immediately back of the slope crest, it could
be impacted by a future small slide in the upper section of the slope. Such small slides could
also be regressive in nature and work their way inland from the crest if not properly stabilized.
We also have some concerns that installation of a line at the crest of the slope could cause some
destabilization of the existing slope and perhaps some of the landscaping developments that have
been constructed by existing home owners. In particular, the modular block wall development
could be adversely impacted by Alternative 2, and it would be necessary to examine design and
construction details of this wall in more depth to assess potential impacts on it or by it relative to
the proposed sewer line.
The Alternative 3 alignment also will be influenced by sloping ground considerations as it
traverses the slope obliquely in its descent to MH45. Ideally, pipe alignments should follow the
dip or fall -line of a slope to present the least amount of exposure to potential instability effects.
However, the cross -sections indicated on Figure 3, show that the slope area traversed by this
alignment is flatter than the upper part of the slope, which we believe to be near the angle of
repose of recessional outwash sand deposits (i.e. between 30 and 34 degrees). This means that
the existing factor of safety of these flatter slope areas, assuming recessional outwash subsurface
Final Letter Report Task 1 5 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. 2009-05 8-2 1 /Task 1
soils also exist, would tend to be higher and the slope areas more stable. If the slope profile
contains glacial till soils, its stability could be even higher due to increased soil strength in this
material. However, glacial till could also focus perching of ground water, which is to be
considered a slope destabilizing condition that needs to be considered further prior to route
selection. Regardless of sewer line alignment, it is our recommendation that short sections of
trench be excavated, line installed and backfilled prior to opening the next section. This is
particularly important for Alternative 3 on the slope to reduce potential instability in localized
sections of slope above the line.
Pipeline profiles are presently unknown for both alternatives, but it is anticipated that trench
depths between 4 and 10 feet will generally be associated with construction along either
alignment. Because of the degree of ground disturbance associated with sloped -back excavation
walls, we recommend that shoring or trench boxes be employed to limit the trench widths and
amount of soil disturbance, while maintaining safe conditions for workers. This will be
particularly important if seepage water is encountered in any portions of the open trench.
Suitable dewatering methods will need to be employed to maintain trench and localized slope
stability. At this time, we anticipate that ground water conditions will not be a major
consideration, but this needs to be confirmed by an appropriate level of subsurface investigation
in advance of detailed design of any portion of this project.
Typically, pipes should be bedded and trenches backfilled with the appropriate materials meeting
the requirements stated in the 2008 WSDOT Standard Specifications for Road, Bridge, and
Municipal Construction. However, if suitable recessional outwash soils are confirmed by later
investigation of either of the alignment alternatives, it may be possible to use these materials as
trench backfill. Beneath roadway areas, areas to be paved or areas where settlement is a concern,
backfill placed above the pipe zone and to within 2 feet of the ground surface should be
compacted to at least 90 percent of the Modified Proctor maximum dry density (MDD), and
backfill placed within 2 feet of the ground surface should be compacted to at least 95 percent of
the Modified Proctor MDD. In general, we believe it desirable to adopt this level of compaction
as a minimum standard for all sections of pipe in close proximity to or on the slope for this
proj ect.
We recommend that a suitable level of subsurface investigation be performed for this project
prior to completion of detailed design, once it is determined what improvements will be
performed and their most probable site configurations.
CLOSURE
We have prepared this assessment for Carollo Engineers and the City of Renton for use in
preliminary design of this project. The conclusions and interpretations presented in this report
are based upon review of pre-existing field data and should not be construed as our warranty of
existing subsurface conditions. No subsurface investigation was conducted as part of this
assessment. Experience has shown that soil and ground water conditions can vary significantly
Final Letter Report Task 1 6 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. 2009-05 8-2 1 /Task 1
over small distances. Inconsistent conditions can occur between exploration locations and may
not be detected by a geotechnical study of this nature. If, during future site operations,
subsurface conditions are encountered which vary appreciably from those described herein,
HWA should be notified for review of the recommendations of this report, and revision of such
if necessary.
Sufficient geotechnical monitoring, testing, and consultation should be provided during detailed
design and subsequent construction to confirm that the actual conditions encountered are
consistent with those indicated by the explorations, to provide recommendations for design
changes should conditions revealed during construction differ from those anticipated, and to
verify that geotechnical aspects of construction comply with the contract plans and
specifications.
Our work scope did not include environmental assessments or evaluations regarding the presence
or absence of wetlands or hazardous substances in the soil, surface water, or ground water at this
site.
We appreciate the opportunity to provide geotechnical services on this project.
Sincerely,
HWA GEOSCIENCES INC.
Lorne A. Balanko, P.E.
Geotechnical Engineer, Principal
Attachments:
Figure 1 Vicinity Map
Figure 2 Site and Potential Sewer Alignment Plan
Figure 3 Cross -sections A -A', B-B', C-C' and D-D'
Figure 4 Geologic Map
Final Letter Report Task 1 7 HWA GeoSciences Inc.
July 09, 2009
HWA Project No. 2009-058-21/Task 1
REFERENCES
Booth, Derek P and Wisher, Aaron P, 2006; Geologic Map of King County, Washington.
Terra Associates, Inc., 2000; Preliminary Geotechnical Report, Edmonds Avenue Site, Edmonds
Avenue NE and Sunset Boulevard NE, Renton, Washington, consultant report prepared for
Cambridge Homes.
Final Letter Report Task 1 8 HWA GeoSciences Inc.
(-lc ED C N I T n fi
=0 � HWAGEOSCIENCES INC.
VICINITY MAP
WESTVIEW LIFT STATION
RENTON, WASHINGTON
FE
A
NOT TO SCALE
FIGURE NO.
DRAWN BY EFK
CHECK BY LB
--
PROJECT NO.
DATE
06.17.09
2009-058-21
EXISTING 48" DIA MH N0. 5 EXISTING 48" DIA MH N0. 6
N_F 12—HST
SS
48" DIA MH(4')
P..._
ALTERNATIVE 2
EXISTING 48" DIA MH
!--
ALTERNATIAVE 3
• B _ ^^ a..«. A�41
ALTERNATIVE 2 SrhF
ALTERNATIVE 3 h
I ( a
MODIFIED WET WELL OR NEW MH
\ 48 DIA MH (TYP)
Al
Poo —
LEGEND
A A'
ALTERNATIVE 2 LINE
ALTERNATIVE 3 LINE
CROSS SECTION DESIGNATION AND LOCATION
HWAGEOSCIENCES INC
WESTVIEW LIFT STATION
RENTON, WASHINGTON
0' 40' 80' 160'
FIGURE NO.
DRAWN BY EFK /�
SITE AND POTENTIAL L]
SEWER ALIGNMENT CHECK BY LB
PRON:R N0.
PLAN DATE
06.17.09 2008-058-21
CROSS SECTION M N
A -A' > >
Z Z
0 20 40 60 80 100 120 140 180
N
W
CROSS SECTION >
C-C' z
0 20 40 60 80 100 120 140 180
0' 15' 30' 60'
rum. �
SCALE: 1:1 HWAGEOSaENCES INC.
J ����LLLL..JJII
cr
CROSS SECTION z z
Q Q1 7 0 N
0 20 40 60 80 100 120 140
CROSS SECTION
, D-D' N
w
z
240 240
W Q
230 > N.E. 12th Street R/W 230
Z.
220 ce �" 220
210 210
200 200
190 190
180 180
170 170
160 160
150 150
0 20 40 60 80 100 120 140 180
FIGURE NO.
DRAWN BY EFK
WESTVIEW LIFT STATION CROSS SECTION
RENTON, WASHINGTON A -A', B-B',C-C',D-D' CHECK BY LB PROJER NO.
DATE
06.17.09 2008-058-21
LAKE
WASHINGTON
r
tr
' NOT TO SCALE rC
Description of Map Units
Nonglaclal Deposits (Holocene)
O Qw - Wetland deposts
0 Qat - Altuvlum
O m or of - Modified lands/Artifica( flit
Deposit of Fraser Glaclatlon (Pleistocene)
O Qvr - Vashon recesslonat outwash deposits
O Qvt -Vashon sulogtaciat meltout till
Older glacial and nonotaclal deposits (Pleistocene)
0 Qpf - Pre -Fraser deposits, undifferentiated
Bedrock
�11 Tpt - Tukwila Formation
This section is from "Geologic map of King County"
by Derek, P. Booth & Aaron P. Wisher - February 2006
UVA I � HWAGEOSCIENCES INC
GEOLOGIC MAP DRAWN BY EFK FIGURE N0.
CHECK BY LB 4
WESTVIEW LIFT STATION PROJECT NO.
RENTON, WASHINGTON DATE
06.17.09 2009-058-21
58 WV DWG (FIG 4 WV> Plotted. 7/7/2009 225 PM
APPENDIX B
COST ANALYSIS SPREADSHEETS
COST ANALYSIS SUMMARY SHEET - WESTVIEW LIFT STATION ALTERNATIVES ANALYSIS
Total
Direct
Cost
Contingency
General Contractor
Overhead, Profit, and
Risk
Sales
Tax
General
Conditions
Total
Construction
Cost
Allied
Costs
Easement
Costs
Total Project
Cost
25- Year
Life Cycle
Cost
Cost Factors
--
30%
10%
9.5%
5%
--
30%
--
--
--
Project Alternatives
Alternative 1 - Lift Station Rehabilitation""
$52,500
$10,500
$6,300
$6,600
$3,800
$80,000
$24,000
$0
$110,000
$340,000
Optional Force Main Re -Routing
$22.600
$6,800
$3,000
$3,100
$1.800
$40,000
$12,000
$0
$52,000
—
Alternative 2 - Gravity Sewer Route
$201,900
$60,600
$26,300
$27,500
$15,900
$340,000
$102,000
$10,000
$460,000
$490,000
Alternative 3 - Gravity Sewer Route
$180 300
$54 100
$23,500
$24 600
$14 200
$300 000
$90 000
$12 000
$410 000
$440 000
Notes
(1) Contingency = 20 percent.
The cost estimate herein is based on our perception of current conditions at the project location. This estimate reflects our professional
opinion of accurate costs at this time and is subject to change as the project design matures. Carollo Engineers have no control over
variances in the cost of labor, materials, equipment, nor services provided by others, contractor's means and methods of executing the
work or of determining prices, competitive bidding or market conditions, practices or bidding strategies. Carollo Engineers cannot and
does not warrant or guarantee that proposals, bids or actual construction costs will not vary from the costs presented as shown.
c
Project: City of Renton Wastewater Lift Stations
Job #: 8235A00
Location Renton, WA
Element: 01 Westview Upgrades
DETAILED COST ESTIMATE
Date : June 4, 2009
By : Tyler Whitehouse
Reviewed: Brian Casey
SPEC. NO.
DESCRIPTION
QUANTITY
UNIT
UNIT COST
SUBTOTAL
TOTAL
Division 02 - Site Construction
02000
02000
02220
02220
02220
Misc Site Restoration Allowance
Mob/DemobAllowance
Core Drilling, 3" Diameter
Asphalt Pavement Cutting30.00
Non-Reinf Conc Pavement Cutting - _
1.00
8.00
2.00
192.00
LS
HR
LF
WFT
inFT
$2,300.00
$300.00
$43.64
$.78
$1.33
$2,300.00
$2,400.00
$87
$23
$255
-
02220
Remove 2"-3"Asphak Pavement
5.00
SF
$.37
$2
02220
Remove Non Reinf Conc Pavement To W Thk
60.00
SF
$1.01
$61
02220
Concrete Curb/Gutter Demolition
10.00
LF
$5.02
$50
02220
Demo D.I. Pipe From Trench, 4" - 18' Incl. Fitdngs
20.00
LF
$7.59
$152
02220
Asphalt Pavement Cutting
120.00
inFT
$.78
$94
02220
Remove 2'-3" Asphalt Pavement
60.00
SF
$.37
$22
02220
V High Chain Link Fencing Demolition
30.00
LF
$2.91
$87
02240
02240
02300
02300
02300
02300
02300
2Hp Submersible Pump, 2" Elect.
2Hp Submersible Pump, 2' Elect.
Cat 225 Trackhoe, 3/4Cy Bucket, Class B (Medium
Digging), 0-16' D
10 Cy Dump Truck, 20 Miles/Round Trip
Tractor/Backhoe, 12" Bucket Class B (Medium Digging), 0-
5' D
Native Trench Backfill/Uncorfined Struct. Bf, Class B
Material
Tractor/ Backhoe, 12" Bucket Class B (Medium Digging), 0-
5' D
20.00
20.00
23.70
23.70
0.74
0.74
7.41
DAY
DAY
CY
CY
CY
CY
CY
$88.32
$88.32
$6.83
$15.03
$43.80
$17.31
$43.80
$1,766
$1,766
$162
$358
$32
$13
$325
02300
Imported Pipe Bed & Zone/Confsued Structure Backfill,
Class B Material
2.22
CY
$68.64
$152
02300
10 Cy Dump Truck, 20 Miles/Round Trip
2.22
CY
$15.03
$33
02742
3' Pavement Replacement On 4" Abc Over Trench
5.00
SF
$5.75
$29
02742
3" Pavement Replacement On 6' Abc Over Trench
60.00
SF
$6.18
$371
02772
6" Thick Concrete Sidewalk
60.00
SF
$5.61
$337
02772
4' Gravel Base a Sidewalk
36.00
SF
$1.05
$38
02772
24" W Straight Conc Curb And Gutter, Hand Formed
10.00
LF
$13.33
$133
Total
$11,047
Division 03 - Concrete
03000
Precast Concrete Valve Vault
1.00
LS
$5,195.00
$5.195.00
03000
Miscellaneous concrete formwork in wet well
1.00
LS
$2,846.86
$2,846.86
Total
$8,042
Division 08 - Metals
050DO
Miscellaneous stainless steel anchor replacement
1.00
LS
$1,475.38
$1,475.38
Total
$1,475
Division 11 - Equi ent
11000
Barnes XSGV2042L Grinder Pump
2.00
EA
$3.435.81
$6,871.63
11000
Vault Sump Pump and Accessories
1.00
LS
$1,059.78
$1,059.78
Total
$7,931
Division 15 - Mechanical
15000
1-1/2" Flexible Coupling
4.00
EA
$73.60
$294.41
15000
Barnes SS Duplex Guide Rai System
1.00
LS
$2.891.12
$2,891.12
15000
Miscellaneous pipe/equipment surts
1.00
LS
$1,994.88
$1,994.88
15000
Barnes Moveable Discharge Fitting Assembly
2.00
EA
$1.320.26
$2,640.51
15000
Miscellaneous Mechanical
1.00
LS
$1,246.80
$1,246.80
15000
1-1/2" Dezurik Eccentric Plug Valve, Threaded
3.00
EA
$220.31
$6W.93
15000
Misc Mechanical Bypass Pumping
1.00
LS
$374.04
$374.04
15114
1-1/2" 1258 Bronze Thrd Check Valve
2.00
EA
$137.19
$274
15116
3" Fxf Cast Iron Plug Valve W/Handwheel Op
1.00
EA
$643.26
$643
15251
3' Fig Ck6 Pipe In Open Trench
20.00
LF
$35.75
$715
15255
1-1/2' 40S 316L Threaded Sst Pipe
10.00
LF
$53.54
$535
Total
$12,271
fm W*SM LS R- Calf Ea -M• AC 1 .I1-01 'W,iMtiv Upy" n Page 1 of 2 FM„ Ibr ICO.IIM
DETAILED COST ESTIMATE
Project:
City of Renton Wastewater Lift Stations
Job #:
8235A00
Date:
June 4, 2009
Location:
Renton, WA
By :
Tyler Whitehouse
Element:
01 Westview Upgrades
Reviewed:
Brian Casey
SPEC. NO.
DESCRIPTION
QUANTITY
UNIT
UNIT COST
SUBTOTAL
TOTAL
Division 16 - Electrical
16000
Junction Box
2.00
EA
$1,101.34
$2,202.68
- -
16000
Miscellaneous Electrical
1.00
LS
$1,454.60
$1,454.60
16000
Trenched Conduit Allowance
1.00
LS
$2,078.00
$2,078.00
1.5' Sch 40 Pvc Rigid Conduit Run, In A Bldg W/Unlimded
16130
Fit
150.00
LF
$8.14
$1,220
Total
$6,956
Division 17 - Instrumentation and Controls
17000
Backup Level Float System
1.00
LS
$1,475.38
$1,475.38
17000
Level Transducer
1.00
LS
$2,202.68
$2,202.68
17000
Misceganeous Instrumentation
1.00
LS
$1.039.00
$1,039.00
Total
$4,717
Grand Total
$52,440
fm w.�-LS R.— c.11 Ew M. AA I .I"I IV.v.,w. U99— Page 2 of 2 Fom R- 2008-e
DETAILED COST
ESTIMATE
Project:
City of Renton Wastewater Lift Stations
Job #:
8235A00
Date :
June 4, 2009
Location:
Renton, WA
By :
Tyler Whitehouse
Element:
01 Force Main Re -Routing
Reviewed:
Brian Casey
SPEC. NO.
DESCRIPTION
QUANTITY
UNIT
UNIT COST
SUBTOTAL
TOTAL
Division 02 - Site Construction
02000
Connection Allowance
1.00
LS
$519.50
$519.50
02000
Misc Site Construction
1.00
LS
$Z078.00
$2.078.00
02220
Asphalt Pavement Cutting
1,500.00
inFT
$33
$1,169
02220
Remove 2'-3' Asphatt Pavement
875.00
SF
$ 37
$326
Tractor/Backhoe, 12" Bucket Class B (Medium Digging), 0-
02300
6 D
55.56
CY
$43.80
$2,434
Imported Pipe Bed 8 Zone/Confined Structure Backfdl,
02300
Class B Material
13.89
CY
$68.64
$953
02300
5 Cy Dump Truck, 10 Miles/Round Trip
13.89
CY
$12.67
$176
02742
3" Pavement Replacement On 4' Abc Over Trench
875.00
SF
$5.75
$5,027
Total
512,88:i
Division 15 - Mechanical
15000
Misc Mechanical
1.00
LS
$935.10
$935.10
15251
3' FIg Ckfi Pipe In Open Trench
250.00
LF
$35.75
$8,936
Total
$9,872
Grand Total
$22,1555
fm Wts Force Man AC r Cost Es ate AN 1 r1a 01 F=* Man R►AtWmg Page 1 of 1 Fo m Rev. 2009,N
--y
Project: City of Renton Wastewater Lift Stations
Job #: 8235A00
Location: Renton, WA
Element: 01 Westview Gravity Alt 2
DETAILED COST ESTIMATE
Date :
By :
Reviewed:
June 4. 2009
Tyler Whitehouse
Brian Casey
SPEC. NO.
DESCRIPTION
QUANTITY
UNIT
UNIT COST
SUBTOTAL
TOTAL
02000
02000
02000
02000
Division 02 - Site Construction
DiKcukAccess Allowance
Misc Site Restoration Allowance
Misc Geotech Allowance
Additional Demo-Repl Mods Q Wet Well
1.00
1.00
1.00
1.00
LS
LS
LS
LS
$10.000.00
$10.000.00
$20,000.00
$2.000.00
$10,000.00
$10,000.00
$20.000.00
$2,000.00
02000
Exst Utilities Relocation Allowance
1.00
LS
$5,000.00
$5,000.00
02220
Demo Concrete Walls, Heavy Reber, 6'
285.00
SF
$13.92
$3.969
02240
10Hp Submersible Pump, 3" Elea
20.00
DAY
$144.42
$2,8W
02260
Trench Bracing, Y W X 10' D, Wood Planks & X-Braciing
780.00
LF
$16.62
$12,967
02260
12' D X 12' W Trench And Manhole Boxes
30.00
DAY
$72.73
$2.182
02300
Cut & Remove Tree, 8" Diameter
1.00
EA
$415.60
$418
02300
Cut & Remove Tree, 24" Diameter
3.00
EA
$675.35
$2,026
02300
Clearing & Grubbing Equipment Move -On Cost
1.00
LS
$1,555.50
$1,559
02300
Imported Pipe Bed & Zone/Cortfxhed Structure Backfill,
Class B Material
144.73
CY
$68.84
$9,935
02300
Remove Grass & Shrubs, 4" Depth To 1 Acre
0.22
AC
$1,106.49
$243
02300
Cat 225 Trackhoe, 314Cy Bucket, Class B (Medium
ing), 0-16 D
520.00
CY
$6.83
$3,552
02300
Cat 225 Treckhoe, 3/4Cy Bucket, Class B (Medium
Digging), 0-19 D
106.67
CY
$6.83
$729
02300
10 Cy Dump Truck, 20 Miles/Round Trip
144.73
CY
$15.03
$2,175
02300
D4 Dozer, Class B (Medium Dig), Grade, Cut, Fill &
Compact, 30U' Haul
592.59
CY
$17.74
$10,514
02300
Native Trench BackfdUUnconfined Stnrct. Bf, Class B
Material
375.27
CY
$17.31
$6,497
02300
Slope Protection Akowance
2,250.00
SF
$20.78
$46,755
02300
02580
10 Cy Dump Truck, 20 Miles/Round Trip
48" X 8' Deep Precast Manhole, No Ring & Cover, No
Earthwork
165.37
4.00
CY
EA
$15.03
$1.793.10
$2,486
$7,172
02590
48" Manhole Precast Slab Top Or Bottom, $" Thick
4.00
EA
$317.73
$1,271
025M
Galy. Steel Standard Ste (Precast In Manhole)
36.00
EA
$16.21
$584
02580
24" Div. X 350 Lb Watertight Manhole Frame & Cover
4.00
EA
$555.53
$2,222
02580
2" Precast Grade Ring, 4-Piece, 20" - 26" Diameter
4.00
EA
$522.45
$2.090
02580
Concrete Manhole Invert, Single Channel
4.00
EA
$305.66
$1,223
02820
GaN. Chain Link Fence, V W/Barbed Wire, No Gates
80.00
LF
$48.31
$3,WS
02900
Sodding
2,500.00
SF
$.91
$2,2W
02900
Landscaping, High Visual lrnpscl, Medium Areas
2,500.00
SF
$6.49
$16,234
02900
Imported Topsoil, Furnish & Place, 4" Deep
2,500.00
SF
$.42
$1,039
Total
$183,871
Division 18 - Mechanical
15000
Misc Mechanical
1.00
LS
$831.20
$831.20
15265
Be Sdr-26 Pvc Sewer Pipe, In Trench
780.00
LF
$9.19
$7,188
Total
$7,999
Grand Total
$201,876
rm West -Gr@, y Cosi Est-lo An 2.u-01 W-M+ G-*y An 2 Page 1 of 1 F-r-lpp�yy
Project: City of Renton Wastewater Lift Stations
Job #: 8235A00
Location: Renton, WA
Element: 01 Westview Gravity Alt 3
DETAILED COST ESTIMATE
Date:
By :
Reviewed:
June 4, 2009
Tyler Whitehouse
Brian Casey
SPEC. NO.
DESCRIPTION
QUANTITY
UNIT
UNIT COST
SUBTOTAL
TOTAL
02000
02000
02000
Division 02 - Site Construction
Difficult Access Allowance
Misc Site Restoration Allowance
Misc Geotech Allowance
1.00
1.00
1.00
LS
LS
LS
$5.000.00
$10.000.00
$10,000.00
$5,000.00
$10,000.00
$10,000.00
02000
Additional Demo -Re I Mods @ Wet Well
1.00
LS
$2,000.00
$2,000.00
02000
Exst Utilities Relocation Allowance
1.00
LS
$1,000.00
$1,000.00
02220
Demo Concrete Walls, Heavy Rebar, 8'
285.00
SF
$13.92
$3,969
02240
10Hp Submersible Pump, 3' Elect.
60.00
DAY
$144.42
$8,665
022W
Trench Bracing, 3 W X VY D, Wood Planks & X
720.00
LF
$16.62
$11,969
0226D
17 D X 17 W Trench And Manhole Boxes
30.00
DAY
$72.73
$2,182
02300
Cut & Remove Tree, 8" Diameter
16.00
EA
$415.60
$6,650
02300
Cut & Remove Tree, 24" Diameter
1.00
EA
$675.35
$675
02300
Clearing & Grubbing Equipment Move -On Cost
1.00
LS
$1,558.50
$1.559
02300
Imported Pipe Bed & Zone/Confined Structure Backfill,
Class B Material
133.00
CY
$68.64
$9,171
02300
Remove Grass & Shrubs, 4' Depth To 1 Acre
0.24
AC
$1,106.49
$266
0230D
Cat 225 Trackhoe, 314Cy Bucket, Class B (Medium
Digging), 0-16 D
720.00
CY
$6.83
$4,918
02300
Cat 225 Trackhoe, 3f4Cy Bucket, Class B (Medium
Digging), 0-16 D
84.44
CY
$6.83
$577
02300
02300
10 Cy Dump Truck, 20 Miles/Round Trip
D4 Dozer, Class B (Medium Dig), Grade, Cut, Fill &
Compact, 300' Haul
133.60
1.570.37
CY
CY
$15.03
$17.74
$2,008
$27,862
02300
Native Trench BacIffAUUnconfined Strud. Bf, Class B
Material
586.40
CY
$17.31
$10,153
02300
Slo Protection Allowance
1,500.00
SF
$20.78
$31,170
023M
10 Cy Dump Truck, 20 Miles/Round Trip
130.92
CY
$15.03
$1,908
02580
48' X V Deep Precast Manhole, No Ring & Cover, No
Earthwork
3.00
EA
$1,793.10
$5,379
025W
48" Manhole Precast Slab Top Or Bottom, 8' Thick
3.00
EA
$317.73
$953
025W
Galy. Steel Standard Steps (Precast In Manhole)
56.00
EA
$16.21
$908
025W
ZC Dia. X 350 Lb Watertight Manhole Frame & Cover
3.00
EA
$555.53
$1,667
025W
2" Precast Grade Ring, 4-Piece, 20" - 26" Diameter
3.00
EA
$522.45
$1,567
02580
Concrete Manhole Invert, Single Channel
3.00
EA
$305.66
$917
02820
GaIv. Chain Link Fence, 8' WBarbed Wire, No Gates
80.00
LF
$48.31
$3,865
02900
Sodding
2,000.00
SF
$.91
$1,829
02900
Landscaping, High Visual Impact Medium Areas
500.00
SF
$6.49
$3247
029M
Imported Topsoil, Furnish & Place, 4' Deep
2,000.00
SF
$.42
$831
Total
$172,923
Division 15 -Mechanical
15000
Misc Mechanical
1.00
LS
$727.30
$727.30
15265
8" Sdr-26 Pvc Sewer Pipe, In Trench
720.00
LF
$9.19
$6,616
Total
$7,344
Grand Total
$190
fM W.S C- y C.0 EU1 M. All 3 ♦b-Ot W.� G-4y AN 3 Page 1 of 1 Fee Mr. 1ooRMw
WnI—LRI Slat— RWu501t—,
ARrandl- I - LYl St b,,I RWIY ad,0—
365
• Pw.y �1av� >1a1 U.0: yr� reY 350 7
WIP SIaR wells prr rrar 511+
p_I 5tam CYf51 JIaY Mrvvaaa. 6
C6M-1Yxr wx1NI-II(srt111s m00 Px Tt6D
Ek�1C)I I—,c—'sAw.Mr)s 006 IMW=1 NW
Parry Operaorp W.-,.ry 0W.... CY<
rLAk
YERICO
C A►ITAL COSTS
.rpa0es nx anhr 91arMa 1
ww� ol,rr.w
SlaSon Mvubr Maa3xwrlre
a Deal+W
crlanrw.s EQupnmt
RISK
u 96 O11rW
PIEBRIT VALUE a COSTS
PRES EW VALUE a BENEFIT
CUMULATIVE POMBENT VALUE of COSTS
CWILATIVE PIIESENT VALUE a BENEFITS
YTIV CLLAE P1Kl31T VALLE A41
*RETEST RATE
TOTAL PRESENT VALUE of COSTS
TOTAL PRESENT VALLE a M ER78
BENEFIT 10 COST RATIO
NET PIIBS6M VALUE W%
0 1 2 3 4 6 6 7 / e 10 11 12 13 14 16 A 17
et 10A00
23.105
I t0 000 0 0 0 0 M.105 0 0 0 0 0 0 0 0 0 0 0 0
73 M 7a Sa 77 3P :W b Y3 +5 +i +0 m 51 61 54
]B10 1. +,07� 1,1oo e,322 +!52 �685 /.133 1— 11016 5.161 5315 5+11 5b39 2AOe 5.M3 uet e.3e7
I no I31S lme 1321 I,ml 1m4 1570 15i� 10:1 I$ a 1730 1 772 1 015 1 NO I= IAeb 2Am 7,11e
550 Y! N3 SOi 116 all 551 Lis d5) 116 131 i51 111+ .8 122 e57 e13 No
115.M SAm 5.46e 5.3e3 5.200 13am 5.091 2,964 4.609 +.M !705 +915 4527 2,M1 4,351 4,112 2,192 4,112
115.703 171]61 lalm 133,157 137,N0 WIN 156,975 110.m 17514 1005+0 I05251 INNii /m]e7 198.6m M.1e1 A7.406 211,057 113770
115,7W - 171297 - 130,761 133.1E - 137,W . Im.18. 155975 . 1M= 1751+9 - 190515 - IB5151 . INM . INXI - Ibe.633 . 363.191 - 207.456 . 211 M67 - 315170
U16 5A15 70k
e e11i11 s 333T1+ 1 291,405
6 5 s
682 0 w 0 w
Kum 333,214 .5 161,m5
wYst— Lin 51411pn RMupiMa11M1
AOwn40re 1 -Lin Slaflon R4B1iSfEi�P11
�:)yri ra`Y Drysler'ie
.r m Sun DM per rear
`WfP SUBV pertear
RriP SW41 CAPYEu1SeiPntnl41 CM UNi/
IrBt1w)
Porr CnISw)
3eeeq Dm
MrvOry
10
COSTS
rYrfLBn rw SYoBR PYrryel
.,ten
SENT VALLE d COSTS
SENT VALUE E BENEFIT
LLA7NE PRESENT VALUE of COSTS
ILLATIVE PRESENT VALUE of DENMTS
LIATIVE PRESENT VALUE (E•C)
T3ESTRATE
AL PRESENT VALUE of COSTS
AL PRESENT VALUE of BENEFI rS
EAT to COST RATIO
PRESENT VALUE wV)
0 0 INA72 _ 0 _ 0 —15
� Si 5Y 61 83 65 fE B5
5 537 6 '33 6 Y:tl I tM I,358 151Y i 806 B Y1Y
±.ti5 2244 ±117 2lBl 1,451 2528 ).BPI 2AB0
976 BB4 9Bl t0:i 1054 IABS I.ttB 1.152
- I I I 1 -- -- I _ 1- -_
4" 3.451 IB,iRI 3.m 3.136 3.014 3-594 15.11Y2 - - - - -
21 YA0U 223.7E1 MIA 300328 310O63 313,/29 317.3n 333,214 333.214 333,214 333,2i4 333%4 WU 14 333,24 T33,214 M3,214 333,214 MU14 333,2/4
21 DAN - 223.761 . 302.520 - 30.328 - MAN - 313,726 - 311.322 - 333,214 - 333.244 - 333.214 . 333,114 . 333.214 - 333.214 - 333,21. - 333.214 - 333,714 - 333214 333214 - 333214
Pq. 2J3
W..trl..v Lm SI-- R.Iw6r1r1E
All h-2-OlaWty 0NmirGoole
.M......... belles ltnel t M UPn Tea(..
YEAR
OtA3/
01/10
OW
602
OIA3
01/14
0V16
01/I6
OV17
Ot/16
Ot/N
Otm
CIM
OtA2
Owu
OVA
Oto
OVA
PERIL we
0
1
2
3
6
6
6
7
6
1
10
11
12
13
N
16
16
17
CAPITAL COSTS
.. ee nyre 2
t4%000
1� A.y,ewn
{103B0
TOTAL PRMCT COOK
450"
0
0
0
a
a
a
0
a
a
o
a
0
a
0
0
0
0
Oromm"•mllk�COE11
0-*sw-p rMa./fnac.
1210
till
051
12t/
iN1
1.464
1We
IA7.
I,621
'Ale
1.T70
1,772
IA25
IAM
1A3/
IAW
2AW
2.115
TOTAL OPERATM COSTS
I No 1
1318 1
358 I
"Ng I
1 Nd
1,6211
157.1
IA21 1
1 670 1
11201
1,1721
1,8251
I No I
I we I
1 m 1
205.1
2116
01911( 18
TOTAL RISK COSTS
TOTAL COE111
.e1M
1310
1358
1W.
iHl
1,4/4
1,528
1574
1021
1670
1720
1712
1B25
1,900
1038
1Ap.
2.05.
1116
RAM
K Et)MR7f
u z C11nArlwl.
PRESENT VALLIE of COSTS
4a1N0
125e
1.712
I'm
1.185
1163
II.I
1.110
1007
1077
105e
Ime
1016
a
979
%9
NI
923
PRE SENT VALLE al BENEFIT
-
CI,MIAATIVE PRESENT VALLE of COSTS
4611B2
.e253fi
163.747
.e.AM
.00,161
4e7$3
.1945.
409.W)
.]O.Ma
471767
412AI3
173,W
114 etl5
415.1
.Ie—
4171%
.1..IQ
.71Ae3
LUAU THE PRESENT VALUE of BENEFITS
-
-
-
-
-
-
CLULLATNEPRESENT VANEI&CI
.91m
.925A
N11/7
101.1170
411111.1111
.97.323
.BS,.BI
44111.583
470AN
471757 -
112AI3
473 AN -
47..Be5 -
.75082
416,W
477188
.78.1.0
472 A83
INTEREST RATE
i,AL
S OSi
7 0%
TOTAL PRESENT VALUE of COSTS
/
MAN 1
199 M2 1
191,525
TOTAL PRESENT VALLE of BENEFITS
/
0 1
8EEFITI. COST RATI O
SA/
000
ow
IrT PllfffilT VALUE pPVI
♦
MMY
�Be,..2 It
.81,526
Inp 2— Pape 1. 3
Wg,,IAi— LIR Stall R�.
ARWii.b-2 9... By S—R6IS6
LA1.
PERIOD NO
CAPITAL COSTS
1
n r.6r ''+e..a RpMBwlrlacl
2,IA
2,2N4
2.112
2.311 2662
2.525
2,011!
2,6W
OPERATING COSTS
2,1i0�
2,2M�
2
2453L
:s.
2.6621
2586� -
(TOTAL
A" COSTS
TOTAL RISK COSTS-
OTAL Cos Ts-
2110
2 2M
2,312
2,381 2,453
2,620
1002
2.6w
B�iPRs
-
TOTAL BBII ...
u % CAIr4Yar
PRESENT VALUE dCOSTS
605
m
071
%5 sm
m
607
701 - - - - -
PRESENT VALUE ofBENEFIT
-
-
CIMLATNE PRESENT VALUE of COSTS
N60566
WAS?
NO] 320
43.163 MN 021
4".8"
306A60
.0,142 46.1.2 A06M7 40S442 N66,M2 NBO.A42 45,442 466AA2 06M2 K8,442 0O.M2
CUMULATIVE PRESENT VALUE of BENEFITS
-
CLYLATNE PRESENT VALUE (BC)
N00560
41A67
M2.326 -
K3.IW 44221 -
N ,w
Q5.6 0 -
N118 AN2 40SM2 NBOM2 - 46,442 - 41116,442 N .4,Q 06,M2 N6M2 - Y .M2 46,442 NB6.M2 - NO.AA2
INTEREST RATE
TOTAL PRESENT VALUE ofCOSTS
TOTAL PRESENT VALUE ofBENEFITS
BENEFIT to COST RATIO
NNBR PMSI NT VALLM BI►VI
P606 203
Wes Ai -LA SIY1en Rs414n111t411en
Alt, n4tNvs 3 - 014v1ty Si—, Routs
ILA"
It 111W Nf]
CAIITAL COSTS
IITOTAL PROJECT COSTS _ I
OM"A7 a 16A61711ANCE cosh -
01,09 01— a1111 u1:1: 01,13 OIH4 OV16 0VK 01117 01N6 Oil" Oim aim aim 01/23 01M Was Oim
0 1 2 3 ♦ 6 6 T 6 6 10 11 12 16 14 16 16 17
u o 0 0 0 a 0 0 0 0 0 0 U a 0 0
IA21 1A70 1.720 1./72 IS26 1p0 1A36 LBW 2A64 2.115
,-1 1 .01 _1— 1 1,4 1 1yt j_ _'025 _ _ 1Boo I IB361 I —I 2a541 3116
hrQLL GOSfi 1 4113Ba 1318 136E 1399 1.44. 1.464 1A26 fA74 1,621 I.AO 1,720 1772 1,675 1,000 108 1M 21164 3115
SENT VALUE d COSTS
SENT VALUE of BENEFIT
CLAKILATIVE PRESENT VALUE of COSTS
CIARLATIVE PRESENT VALUE of 004ER TS
CLLILA TIVE PRESENT VALUE tB-C3
;INTEREST RATE
(TOTAL PRESENT VALUE of COSTS
TOTAL PRESENT VALUE of BENEFITS
BENEFIT to COST RATIO
Ns7 ►I uff VALVE 04rM
.I,.= 1366
1332
I,1W Mn
1,163
1.1.1
I,IIB
I07
IA77
I'M IA36 IA16 W7 0111
No WI 03
.11.290 417538
413767
.14,976 415,111
417A23
418,454
419,618
420AR1
421.767
.22.813 423,640 42"Wis 125.802 4711.11I0
427,790 426.740 429.M
41 I.M 412AM
113767
.14,076 - 41e191 -
417= -
418,4W
419.603 -
420AS
421,757
422A13 In" - 4AA66 Q3.662 - 420.140
427.710 421.740 - 42MA63
6 ARM 1
43B.M2 1
431526
6
0 1
64►
0 Bo
0 w
4 40WO
.36.442 -S
431,525
Rye 1a3
wnt— Lift SINon RYRatlYtldwn
AR—t— 3 - G—y Si,—, Rout
—u 9 Ppa 2d3