Comprehensive Study of the Sanitary Sewer Collection System March 8, 2021OT642 REPORT 3-8-2021
CITY OF OTSEGO
COMPREHENSIVE STUDY OF
THE SANITARY SEWER COLLECTION SYSTEM
I hereby certify that this plan, specification, or report was prepared by me or under my direct
supervision and that I am a duly Licensed Professional Engineer under the laws of the State
of Minnesota.
Signature: Type or Printed Name: Ronald J. Wagner, P.E.
Date: March 8, 2021 License No: 26052
OT642 REPORT 3-8-2021
Adopted by:
THE CITY OF OTSEGO
on
March 8, 2021
City Officials
Jessica Stockamp, Mayor
Tom Darkenwald, Council Member
Tina Goede, Council Member
Brittany Moores, Council Member
Jeff Dahl, Council Member
By:
Hakanson Anderson Associates, Inc.
Engineers
Ronald J. Wagner, P.E.
Brent Larson, P.E.
Graphics
Sam Morse
Dalton Wagner
The Planning Company LLC
Planner
D. Daniel Licht, AICP
TC-1
TABLE OF CONTENTS
I. PURPOSE OF REPORT Page 1
II. SERVICE AREA ANALYSIS Page 3
III. CAPACITY OF EXISTING TRUNK FACILITIES Page 6
IV. FUNDING OF TRUNK SEWER PROJECTS Page 21
V. RECOMMENDED PROJECTS Page 22
VI. RECOMMENDED CAPITAL IMPROVEMENT PROGRAM Page 22
APPENDIX
LIST OF EXHIBITS
Exhibit No. 1, Study Area Map
Exhibit No. 2, Future Land Use Map
Exhibit No. 3, Lift Station Map
Exhibit No. 4, Sanitary Sewer Collection System Index Map for 1’=200’ Detailed Maps: 1-3 of 52
Exhibit No. 4, Sanitary Sewer Collection System 1’=200’ Detailed Maps: 4-52 of 52
Exhibit No. 5, Proposed Lift Station Wet Well Geometries
Exhibit No. 6, Proposed Pump Selection – Pump Curves
LIST OF TABLES
Table No. 1, Population Projection (TPC)
Table No. 2E, East Lift Station Projected REC Summary
Table No. 2W, West Lift Station Projected REC Summary
Table No. 3E, East Lift Station Projected Sanitary Sewer and Forcemain Sizing
Table No. 3W, West Lift Station Projected Sanitary Sewer and Forcemain Sizing
Table No. 4, Existing Lift Station Summary
Table No. 5, Proposed Lift Station Summary
Table No. 6, Recommended Capital Improvements Program
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I. PURPOSE OF REPORT
A. General Purpose
The general purpose of this report is to evaluate the needs of the City of
Otsego’s trunk sewer collection system in order to serve the projected growth of
the City of Otsego over the next 20 years and beyond. Exhibit No. 1, Study
Area Map, shows the entire City of Otsego and the areas anticipated to be
ultimately served by municipal sewer. The City of Otsego has recently
completed two other related long-term plans for municipal services, a
Comprehensive Otsego Drinking Water System Master Plan (January 2020)
and Otsego Wastewater Treatment Facilities Master Plan (February 2018).
B. Service Areas Description
The City of Otsego is topographically divided into two service areas by a
general high point that crosses the City in a south to north direction generally
west of Nashua Avenue. This separation line designates east from west sewer
service areas and was determined by a natural ridge line, along with the desire
to allocate as much sewer as technically and economically possible to the East
Waste Water Treatment Facility (E-WWTF). The E-WWTF has many items in
its favor, including a larger property with easier opportunity for expansion, the
Bios Solids treatment necessary to complete the final step of sewer processing
without the need to transport over road, and more favorable outfall limits than
the West Waste Water Treatment Facility (W-WWTF).
This division is functional for development of two separate gravity-based sewer
collection systems that serve the City. The E-WWTF has a capacity of 1.0
MGD. At this time, the City has initiated the design of expansion of the W-
WWTF to 1.8 million gallons per day (MGD) up from the original capacity of 0.6
MGD. Both east and west systems have their own independent set of sanitary
sewer lift stations, force mains and trunk sewer lines. As a City, the trunk costs
are combined and an overall Sewer Access Charge (SAC) and Sewer
Connection Charge (SCC) are applied to development to fund the City trunk
system.
In the 20 or so years since City water and sewer utility systems have been in
service, there has been a significant amount of residential, industrial, and
commercial growth in the City. As a result of this growth, the City
commissioned an update of the City’s Comprehensive Plan in 2012, which has
most recently been amended in 2018. This plan evaluated the growth patterns
and established an orderly growth plan consisting of land use development,
transportation improvements, park improvements, as well as designations of
where urban development should be encouraged and planned for. The
Comprehensive Plan also establishes policies for expansion of utilities for
development in specific sections of the City.
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The purpose of this report is to present the City Council and City staff with an
updated evaluation of the additional trunk collection sanitary sewer
infrastructure improvements necessary to provide for orderly urban
development. This report evaluates approximately 7,137 acres of land that can
be served in the next 40 years. This is in addition to the 7,044 acres of land
that is or can currently be serviced by the existing lift stations.
C. Basic Logic of Study
The cost of the trunk sewer main extensions is financed by the developers as
they subdivide land within the City. If there are trunk oversizing costs for
extension to other properties contiguous to the new development, the City
determines and allows partial credit of the SAC fees generated by the
development back to the developer for these trunk oversizing costs.
Some areas of Otsego have previously been developed into large lots (one acre
or more) prior to the City providing municipal water and sewer services. We
consider these areas unlikely to redevelop or request municipal water and
sewer services within the next 40 years.
Other areas considered unlikely to develop with municipal water and sewer
services in the next 40 years are:
• Areas subject to Wild and Scenic Recreational River Designation in
accordance with Minnesota Rules along the Mississippi River;
• Areas of the City that due to distance to the treatment facilities and the vast
amount of existing developable acreage will remain much as they are today;
• Areas in the northwest or western edge of the City where large lot
development is guided due to challenges of providing municipal sewer;
• DNR owned property, Otsego County Park, and flood way areas of the
Mississippi and Crow Rivers.
Combined these areas constitute 4,735 acres. It is expected that ultimate
development of the City will provide municipal water and sewer services to 75
percent of its 18,916 acres.
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II. SERVICE AREA ANALYSIS
A. Population Projections
Population projections for the entire City of Otsego have been updated by the
City Planner as of November 2020 for the period from 2020 to 2040. These
projections used a 5 and 10 year house hold growth projection rate and the
average number of persons per household to arrive at a population number for
each time period.
These projections are shown in Table No. 1. From past growth rate analysis,
the two WWTF service areas are projected to grow at much the same pace.
It should be noted that the population projection does not provide information on
the projection of industrial, commercial, office, and other non-residential uses.
These types of development are very cyclical in nature and very difficult to
predict. The sewer usage for these non-residential uses has been estimated at
15 percent of the residential for purposes of this report.
B. Residential Equivalent Connection (REC)
1. Sanitary Sewer RECs
The estimated sanitary sewer flow projection for each Lift Station as
shown on Table No. 2E and 2W has been calculated based on the
allocation of specific load factors per acre of area based on designated
land use. This unit of load is called a “Residential Equivalent
Connection” (REC).
In 2004, the City Engineer presented to the Minnesota Pollution Control
Agency (MPCA) information on the actual wastewater flow rates coming
to the WWTFs. This information showed and continues to show, the
actual flow rate was only 150 GPD rather than the design rate of 250
GPD per REC used by the MET Council. The Minnesota Pollution
Control Agency (MPCA) reviewed this flow information and agreed to
lower the treatment allocation rate to 175 GPD per REC. Ongoing
review of flows received at the WWTFs versus the number of RECs
attributed to each WWTF has continued to show 175 GPD per REC is
still a valid ratio. Therefore, for purposes of this report, the 175 GPD per
REC will be used for design purposes for the gravity collection system,
sanitary lift stations force mains and future treatment facility expansions.
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C. Lift Station Designation
The City of Otsego land mass has been divided into lift station service areas so
that detailed analysis can more easily be performed as each lift station service
area has a viable sewer shed area that affects the extension of sewer service to
those areas. The division of the service area according to topographical
features such as ridge lines and drainage basins is very critical for sanitary
sewer analysis.
Of almost equal importance is the breakdown of each lift station area by
potential development within each area. The projection of future lift station
development has been identified through discussions with property owners and
planned development. This is especially important in the timing of the expected
development and the expected demand for sewer services based on the
separate planned developments.
Using the above information, nine proposed lift station areas were identified.
These proposed lift stations were evaluated and lettered A-I with the letter
indicating staff’s estimation of likely construction order. The actual sequencing
of lift station development will be determined at the discretion of the City
Council in accordance with the growth management policies established by the
Comprehensive Plan. Property owners have no entitlement to development
based on the lift station sequencing indicated by this study. An overall view of
these Lift Station areas is shown on Exhibit No.3, Lift Station Map.
D. 1” = 200’ Detailed Mapping
In order to analyze the preliminary engineering details of the Trunk Sanitary
Sewer Collection design for the sewer collection facilities, forty-nine 1” = 200’
scale maps numbered 4 of 52 to 52 of 52 were prepared to collectively form
Exhibit No.4. Exhibit No. 4 includes index maps showing the summary of the
forty-nine 1” = 200’ scale maps for help in locating particular sections of the
overall service area.
A very extensive part of the design effort was development of trunk sewer line
segment locations and profiles for each individual line segment to ensure that
each existing property or parcel within the service area could have access to
the trunk sewer lines by extension of smaller lateral sewer lines. The details of
the line profiles are included on the forty-nine 1” = 200’ maps included in Exhibit
No. 4 as described above. The distance between each manhole, ground
elevation, invert elevation, pipe size and gradient are drawn on these maps.
These maps will be the primary resource for the City when responding to
developers’ questions about what do they need to provide to serve others
besides themselves. This preliminary design information will assist the City
Engineer and developers plan their projects knowing that the upstream and
downstream requirements have already been analyzed.
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E. Land Use Designations
The proposed land use that the City has guided in its 2012 Comprehensive
Plan for this eastern study area is shown on Exhibit No. 2, Future Land Use
Map. The acreage breakdown of the proposed land use of the ultimate service
area is shown in the table below.
As stated earlier in this report, the redevelopment of existing large lot low
density residential areas into smaller lots is quite unlikely. The use of individual
septic tanks and private small wells is a perfectly good way to service these
subdivisions and municipal services is not projected to occur into these
neighborhoods unless required by the MPCA due to environmental concerns or
is requested by the neighborhoods themselves.
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III. CAPACITY OF EXISTING TRUNK FACILITIES
A. Land Use Potential Projections
The City’s 2012 Comprehensive Plan defines the typical low-density residential
development, with public water and sewer available, would have a density of
2.5 single-family units per developable acre. Therefore, all land designated
Low Density Residential will be allocated 2.5 RECs per acre.
The 2012 Comprehensive Plan also defines Low/ Medium Density Residential
land uses as 3 to 6 units per acre and Medium-High Density Residential land
uses as land developed with 7 to12 residential units per acre. Therefore, all
land designated as Low/ Medium Density Residential will be allocated 5 RECs
per acre and Medium-High Density Residential will be allocated 9 RECs per
acre.
Commercial, Office and Industrial uses, excluding any manufacturing that would
have a large water usage and thus generate larger sewer volumes, are
expected to generate an average waste water flow of 1,000 GPD per acre of
developed land. Therefore, all land designated as Commercial, Office or
Industrial will be allocated 6.0 RECs per acre.
Institutional areas (parks, schools, city campus, and other government lands)
are treated as 2.5 RECs per acre. These areas are generally associated with
large tracks of lands with shorter durations of use during non-peak hours for
sewage generation.
Areas that are not easily served by City sewer services and/or are within the
designated Wild and Scenic areas of the Mississippi River will be limited to one
unit per two acres for Residential Cluster guided areas or one per 10 acres for
other areas and be serviced by well and septic until such time as the municipal
service area grows to its boundaries. Due to the fact these areas are either are
outside of the 40year projection window of the report, those areas are not
included as serviced in the report.
B. Trunk Sanitary Sewer Facilities
Table No. 2E and Table No. 2W of the report provides data on the projected
potential sewer demands for the E-WWTF and W-WWTF to serve the entire
16,068-acre ultimate fully-developed service area using 175 GPD per REC.
C. Trunk Gravity Sewers
Typically, the most cost-effective sewer collection systems are designed to
follow the downhill gradients provided by the natural drainage topography. To
make best use of natural gradient, the major trunk sewers should generally
follow the defined streams within the natural drainage basin and then branch
out into smaller sub-trunk lines to provide service to properties. Therefore, the
preliminary location of the proposed trunk facilities in this study will follow the
natural drainage channels. The actual location is expected to be modified to
suit the developer’s plans while still maintaining the service elevations required
for adjacent or upstream properties.
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EAST WASTE WATER TREATMENT FACILITY COLLECTION SYSTEM
EXISTING EAST WASTE WATER SYSTEM
1. East Waste Water Treatment Plant
a. Existing Capacity
The E-WWTF has a capacity up to 1.0 MGD and is currently treating
approximately 0.38 MGD. A minor amount of this flow is from the
original village area of neighboring Dayton.
b. Capacity Upgrade Schedule
The expected wastewater flows to be received by the facility increase
to about 1.0 MGD by 2030. It is therefore recommended that the next
facility expansion be initiated prior to 2030. This project is included in
the Table No. 6, Capital Improvements Program at the end of this
report.
2. Lift Station #1 (Quaday Avenue)
a. Existing Capacity
Lift Station #1 is the major lift station in eastern Otsego. This lift
station will ultimately service 5,572 acres of the East Sewer District’s
8,952 developable acres or 62%. Wastewater from Lift Station #8, C,
D, E, Y and Z will all flow through Lift Station #1.
This lift station consists of a 42-foot deep, 12-foot diameter wet well.
Currently there are two 50 HP and one 40 HP submersible pumps
operating. These pumps lift sewage through a 12-inch and 16-inch
forcemains that are approximately 17,500 feet long and traverses a
98-foot crest on its way to the EWWTF.
Currently the City is using only the 12-inch force mail with a maximum
capacity of 650 GPM. The lift station is handling around 335,000
GPD or 1,915 RECs or 87.5 percent of the E-WWTF existing flows
Since the typical design of lift station pumps are to match the peak
flow rate GPM expected at the lift station at any hour of the day, this
current set up is near capacity.
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b. Projected Flow Rates
The projected flow rates to Lift Station #1 are:
2020 335,000 GPD
2030 600,000 GPD
2040 865,000 GPD
It is recommended to approach the increasing of flow capacity in a
phased plan.
c. Phase I
When the last 40 HP pump needs replacement, it is to be upgraded
to a 50 HP pumps to match the others. Switching to the 16-inch force
main from the 12-inch force main will increase capacity approximately
80 percent to around 540,000 GPD, or a total of 3,085 RECs for an
additional 1,170 REC allowing between 8 to 12 more years of growth.
At some point, the pair of force mains could be used and would allow
each 50HP pump to reach about 1,000 GPM, or with both pumps
running, 1,200 GPM. The 1,200 GPM peak flow rate equates to an
average daily flow of 560,000 GPD or a total of 3,200 RECs for an
additional 1,285 RECs allowing between 10 to 12 more years of
growth. This would allow for development within the East Sewer
District until at least 2030 before additional upgrades would be
necessary. An on-site generator must be added to this important lift
station at this time, capable of handling all future upgrades.
d. Phase II
The 12-inch and 16-inch force mains should be able to handle
considerable amount of flow before the increased head loss through
the system eventually requires placement with a 21-inch force main.
Replacement of the 50 HP pumps with larger horsepower pumps will
be necessary during Phase II.
e. Ultimate
Ultimately, Lift Station #1 will need to handle over 2.5 MGPD. This
will require a small surface building over the lift station housing three
100 HP suction pumps and the addition of a third 21-inchdiameter
force main.
The 4,530 GPM peak flow rate equates to an average daily flow of
2,562,000 GPD or approximately 14,640 RECs. This includes the
providing sewer service to proposed lift stations B, C, and D, as well
as long term service to areas by Lift Stations Y and Z, where on-site
septic systems are used. These long-term lift stations are not
expected to be constructed within the 40-year report period.
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3. Lift Station # 2 (Riverpointe)
a. Existing Capacity
Lift Station #2 serves the isolated area of development in the
southeastern corner of the City along the Crow River between TH101
and the EWWTF.
This lift station consists of a 40-foot deep, 10-foot diameter wet well.
Currently there are two 12 HP submersible pumps operating.
Currently there is a pair of 6-inch force mains that run about 2,650
feet long that traverses a 53-foot crest on its way to the E-WWTF.
From the pump system curves, each of the two current 12 HP pumps
can pump approximately 250 GPM through the two existing 6-inch
force main when acting alone or about 340 GPM with both pumps
running.
Since the typical design for duplex lift stations is for each pump to
match the peak flow rate GPM expected at the lift station at any hour
of the day, this station currently has capacity for an average daily flow
of 92,400 GPD.
b. Projected Flow Rates
The projected flow rates to the Lift Station #2 are:
2020 51,210 GPD
2030 68,075 GPD
2040 68,075 GPD
Ultimate 122,465 GPD
It appears that the current lift station with 12 HP pumps the pair of 6-
inch force mains will meet the future demands until the year 2040.
The second pump would come on if the flow rate exceeds the
capacity of the single pump running. This would occur very rarely.
Therefore, the lift station would be considered sufficient.
When the flow rates exceed the year 2040 projection, the two 12 HP
pumps will need to be replaced. This station was designed and
constructed to allow upgrading the pumps to 25 HP in the future as
needed. The future 25 HP pumps will be capable of about 450 GPM
or the equivalent average daily flow of 180,000 GPD. This exceeds
the project ultimate fully developed service area for this lift station.
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4. Lift Station #5 (Riverplace)
a. Existing Capacity
Lift Station #5 serves the area just east of the Lift Station #2 service
area in the far southeastern corner of the City along CSAH 36 and
the Crow River but east and north east of the EWWTF.
This lift station consists of a 42-foot deep, 10-foot diameter wet well.
Currently there are three (3) 25 HP submersible pumps operating. A
6-inch and 10-inch force main each approximately 1,700 feet long
traverse a 70-foot crest on its way to tie into the two 6-inch force
mains from Lift Station #2.
From the pump system curves, each of the three current 25 HP
pumps can pump about 350 GPM through the existing 6-inch and 10-
inch force main when acting alone or about 440 GPM with two pumps
running.
Since the typical design for a triplex lift station is for two pumps
running together to match the peak flow rate GPM expected at the lift
station at any hour of the day, this station currently has capacity for
an average daily flow of 176,000 GPD
b. Projected Flow Rates
The projected flow rates to the Riverpointe Lift Station are:
2020 232,600 GPD
2030 159,434 GPD
2040 246,991 GPD
Ultimate 334,548 GPD
It appears that the current lift station with 25 HP pumps and the 6-
inch and 10-inch force mains will meet the future demands to near
the year 2040.
When the flow rates increase beyond the 176,000 GPD flow rate, the
three 25 HP pumps will need to be replaced. This station was
designed and constructed to allow upgrading the pumps to 40 HP in
the future as needed. The 40 HP pumps will be capable of about
1,750 GPM or the equivalent average daily flow of 850,000 GPD.
This exceeds the project ultimate fully developed service area for this
lift station. At the time of this upgrade, an on-site generator should be
assessed.
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5. Lift Station #8 (Waterfront)
a. Existing Capacity
Lift Station #8 serves the area just east of Trunk Highway 101 south
of 90th Street and includes the Mississippi Riverwood Association (a
summer seasonal area) along with the area just to the north that is
guided for mixed uses consisting of commercial and/or high-density
residential land uses.
This lift station consists of a 12-foot deep, 4-foot diameter wet well.
Currently there are two, 3 HP submersible grinder pumps operating.
A 3-inch force main approximately 530 feet long traverses a 4-foot
crest on its way to tie into a manhole at the edge of Lift Station #1
service area.
From the pump system curves, each of the two current 3 HP pumps
can pump about 90 GPM through the existing 3-inch force main when
acting alone or about 160 GPM with both pumps running.
Since the typical design for a duplex lift station is for a single pump to
match the peak flow rate GPM expected at the lift station at any hour
of the day, this station currently has capacity for an average daily flow
of 32,400 GPD.
b. Projected Flow Rates
The projected flow rates to the Waterfront Lift Station are expected to
be:
2020 27,000 GPD
2030 33,250 GPD
2040 33,250 GPD
Ultimate 33,250 GPD
It appears that the current lift station with 3 HP pumps and the 3-inch
force main will meet the future demands to near the year 2040, .
Although some consideration of uprading the lift station to larger
pumps and upsizing the short forcemain to 4-inch diameter to
accommodate non-grinder pump sewage for less maintenance
issues.
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PROPOSED EAST WASTE WATER COLLECTION SYSTEM
1. Establish Proposed East Lift Station Districts
Using the natural ridgeline basin approach, augmented by the limitations of the grid
property system, six additional individual Sewer Lift Station Districts were identified
for the foreseeable future. An overall view of these Sewer Lift Station Districts are
shown on Exhibit No.3, “Lift Station District Map”.
The details of the trunk sewer system, such as pipe length and size, proposed
invert elevation, and approximate top of the manhole elevations are shown in
Exhibit No.4. Exhibit No. 4 includes an index map showing the overlay of the forty -
nine 1” = 200’ scale maps for help in locating particular sections of the sanitary
sewer system.
As shown on these exhibits, there are six new east lift stations and multiple force
mains require to serve the ultimate sewer service area. Three (LS X, Y and Z) of
the proposed lift stations are deemed to be long term facilities and are not analyzed
beyond the gravity pipe network and potential volume of sanitary sewer they may
someday generate. Design of the long-term lift stations and gravity trunk sewer
lines are not included in the analysis of this report. A total of four lift stations
(existing Lift Station #8) and three proposed Lift Stations (B, C, and D) all
discharge into gravity lines that flow into existing Lift Station #1.
PROPOSED EAST LIFT STATIONS
Lift Station A (Rice Lake)
Lift Station A has a service area of nearly 15,00 acres and is bound by
TH101 on the east, Oakwood Avenue (CR 137) on the west, 70th Street
(CSAH 38) on the north, and St. Michael to the south.
This lift station is proposed to be a 37-foot deep, 16-foot diameter wet well.
The lift station will eventually need three 50 HP pumps. These pumps will
lift sewage through an 8-inch, 12-inch, and a 16-inch force main that are
approximately 12,000 feet in length and overcome 89-foot crest on its way
to the E-WWTF. The 8-inch force main is existing as it is a remnant of the
original force main for Lift Station #1. This 8-inch force main can be used to
service the area for the 1st 840 RECs or approximately 10 to 14 years. This
would allow the cost of the larger pump upgrades and the additional larger
force mains to be added at a later time thus making the initial construction
cost of the lift station more manageable. The service area is guided by the
2012 Comprehensive Plan for multiple land use types from industrial along
TH101, some medium to high density residential just west of Quaday
Avenue, with mostly low density residential throughout the rest. The lift
station should be considered for an on-site generator.
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Lift Station C (Oakwood Avenue)
Lift Station C has a service area of a just under 200 acres and is located
north of 70th Street (CSAH 38) just east of Oakwood Avenue (CR 137).
This lift station will drain into a manhole on the west edge of Lift Station 1.
This lift station is proposed to be a 41-foot deep 8-foot diameter wet well.
The lift station will be a bi-plex consisting of two 10 HP pumps. These
pumps will lift sewage through 6-inch and 8-inch force mains that are
approximately 3,600 feet in length and overcome 38-foot crest on its way to
a manhole at the edge of Lift Station A’s service area. The service area of
Lift Station C is guided for low density residential land uses by the 2012
Comprehensive Plan.
Lift Station D (Nashua Central)
Lift Station D has a service area of a little over 400 acres and is located
north of 70th Street (CSAH 38) just east of the List Station C service area.
This lift station will drain into a manhole on the west edge of Lift Station C’s
service area.
Lift Station D is proposed to be a 30-foot deep, 8-foot diameter wet well.
The lift station will be a du-plex facility consisting of two 7.5 HP pumps.
These pumps will lift sewage through a 6-inch and an 8-inch force main that
are approximately 1,800 feet in length and overcome 39-foot crest on its
way to a manhole at the edge of Lift Station C’s service area. The service
area of Lift Station D is guided low density residential land uses by the 2012
Comprehensive Plan.
Lift Station E (Nashua North)
Lift Station E has a service area of a little over 500 acres and is located
north of List Station D service area. This lift station will drain into a
manhole on the west edge of Lift Station 1.
This lift station is proposed to be a 32-foot deep, 8-foot diameter wet well.
The lift station will be a du-plex consisting of two 15 HP pumps. These
pumps will lift sewage through an 8-inch force main that is approximately
6,800 feet in length and overcomes a 50-foot crest on its way to a manhole
at the west edge of Lift Station #1’s service area. The service area of Lift
Station E is guided low density residential and institutional (City Campus
and Prairie Park) land uses by the 2012 Comprehensive Plan.
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Lift Station F (River Road)
Lift Station F has a service area of a just over 350 acres and is located
north of List Station #5 service area and is bound by Queens Avenue to the
west, 65th St to the south, and River Road (CSAH 42) to the north. This lift
station will drain into a manhole on the northern edge of Lift Station #5.
This lift station is proposed to be a 25-foot deep, 8-foot diameter wet well.
The lift station will be a bi-plex consisting of two 20 HP pumps. These
pumps will lift sewage through a 6-inch force main that is approximately
1,800 feet in length and overcomes a 43-foot crest on its way to a manhole
at the northern edge of Lift Station #5’s service area. The service area of
Lift Station F is guided for industrial and low-density residential land uses
with a small amount of medium density housing by the 2012
Comprehensive Plan.
Lift Station G (Nashua South)
Lift Station G has a service area of 635 acres and is bound by St. Michael
to the south of 60th Street (CR 137), the West Sewer District to the west,
70th Street (CSAH 38) to the north, and Lift Station A service area to the
east. This lift station will drain into a manhole on the western edge of Lift
Station A.
This lift station is proposed to be a 45-foot deep 10-foot diameter wet well.
The lift station will be a du-plex consisting of two 15 HP pumps. These
pumps will lift sewage through 6-inch and a 8-inch force mains that each
are approximately 2,900 feet in length and overcomes a 29-foot crest on its
way to a manhole at the western edge of Lift Station A’s service area. The
service area of Lift Station G is guided for industrial land uses by the 2012
Comprehensive Plan.
WEST WASTE WATER TREATMENT FACILITY COLLECTION SYSTEM
EXISTING WEST WASTE WATER FACILITY
1. West Waste Water Treatment Facility
a. Existing Capacity
W-WWTF has a capacity up to 0.6 MGD. Currently the W-WWTF
had flows averaging 0.412 MGD in 2020 or the equivalent of 2,358
RECs.
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b. Capacity Upgrade Schedule
The wastewater flows to be received by the facility are expected to
increase to over 0.6 MGD by 2024. Upgrades to the W-WWTF have
been initiated to increase the capacity to 1.4 MGD or an additional
4,571 RECs. In order for the City to need another capacity increase
prior to the end of this report’s time period, 230 new RECs per year
would have to occur within the West Sewer District.
2. Lift Station #3 (W-WWTF)
a. Existing Capacity
Lift Station #3 is the major lift station for most of the current
residential development and the next 10 years of residential and
industrial development within the West Sewer District.
This lift station consists of a 33.5-foot deep, 12-foot diameter wet
well. Currently there are two 50 HP and one 40 HP submersible
pumps operating. These pumps lift sewage through a manifold of 8-
inch, 10-inch, 12-inch, and 16-inch force mains () that are each
approximately 300 feet in length and traverses a 53-foot crest on its
way to the W-WWTF.
Currently the City is using only the 16-inch force main, which has a
maximum capacity of 830 GPM. The lift station is handling around
260,000 GPD or 1,485 RECs currently.
The typical design of a triplex lift station is designed for two of the
pumps to combine to match the peak flow rate GPM expected at the
lift station at any hour of the day. This lift station has the capacity to
handle roughly 415,000 GPD or 885 additional RECs. It is estimated
that within nine years or so this lift station will need larger pumps
installed.
b. Projected Flow Rates
The projected flow rates to the WWWTF Lift Station are:
2020 260,000 GPD
2030 435,000 GPD
2040 610,000 GPD
It is recommended to approach the increasing of flow capacity in a
phased plan.
16
c. Phase I
When the last 40 HP pump needs replacement, it shall be upgraded
to a 50 HP pumps to match the others. Switching to the 16-inch FM
from the 12-inch force main will increase capacity approximately 80
percent to around 540,000 GPD or 3,085 RECs (an additional 1,170
RECs) allowing between 8 to 12 more years of growth. The pair of
force mains would allow each 50HP pump to reach about 1,000 GPM
or with both pumps running 1,200 GPM. The 1,200 GPM peak flow
rate equates to an average daily flow of 560,000 GPD. This would
get the City to near 2030 before additional upgrades would be
necessary.
d. Phase II
The 12-inch and 16-inch force mains should be able to handle
considerable amount of flow before the increased head loss through
the system eventually requires placement of a 21-inch force main.
Replacement of the 50 HP pumps with larger HP pumps will be
necessary during Phase II.
e. Ultimate
Ultimately, the lift station will need to handle nearly 2.6 MGPD. This
may require a small surface building over the lift station housing three
100 HP suction pumps. The lift station has an on-site, on-demand
generator in case of power outages, which is available from the
generator located at the W-WWTF.
The nearly 4,600 GPM peak flow rate equates to an average daily
flow of 2,573,000 GPD or approximately 14,700 RECs. This includes
the providing municipal sewer service to proposed lift stations B, H,
and #6, as well as long term currently septic areas of LS W. This
need is not expected to be constructed within the 40-year report
period.
3. Lift Station #4 (Martin Farms)
a. Existing Capacity
Lift Station #4 (Martin Farms) serves the area bounded by MacIver
Avenue to the west, 60th Street (CR 137) to the south, 80th Street to
the north, and Nashua Avenue to the east.
This lift station consists of a 39-foot deep, 12-foot diameter wet well.
Currently there are three 60 HP submersible pumps operating.
Currently there are 10-inch and 14-inch force mains that run about
7,100 feet in length that traverses a 58-foot crest on its way to the W-
WWTF.
17
Each of the three 60 HP pumps can pump about 760 GPM through
the existing 10-inch force main when acting alone or about 840 GPM
with two of the pumps running.
Since the typical design for a triplex lift station is for two of the pumps
to match the peak flow rate GPM expected at the lift station at any
hour of the day, this station currently has capacity for an average
daily flow of 417,000 GPD only using the 10-inch force main.
b. Projected Flow Rates
The projected flow rates to the Martin Farms lift station:
2020 152,300 GPD
2030 240,000 GPD
2040 327,500 GPD
Ultimate 889,350 GPD
It appears that the current lift station with three 60 HP pumps and
using both the 10-inch and 14-inch diameter force mains will meet the
future demands for the ultimate fully developed service area for this
lift station. An on-site generator should be assessed as flow continue
to increase.
4. Lift Station #6 (Riverwood National- Interim)
a. Existing Capacity
Lift Station #6 currently serves the area of the Riverwood National
development along with Lift Station #9’s small area. The Lift Station
is along Lift Station District I’s trunk gravity sewer line and has an
ultimate drainage area of 600 acres. Lift Station #6’s service area
extends from Riverwood National to the west toward the boundary
with Monticello Township. The north is bound by 95th Street (CSAH
39), excepting Lift Station #9’s service area, and to the south by 85th
Street.
This lift station consists of a 29-foot deep, 8-foot diameter wet well.
Currently there are two 15 HP submersible pumps operating. A 6-
inch force main approximately 9,700 feet in length traverses a 72-foot
crest on its way to tie into a manhole along the trunk gravity sewer
line of Lift Station #3.
From the pump system curves, each 15 HP pumps can pump about
280 GPM through the existing 6-inch force main.
18
The typical design for a duplex lift station is for one pump flow rate
match the peak flow rate GPM expected at the lift station at any hour
of the day, this station currently has capacity for an average daily flow
of 105,000 GPD.
b. Projected Flow Rates
The projected flow rates to the Riverwood National Lift Station are:
2020 21,000 GPD
2030 28,875 GPD
2040 28,875 GPD
Ultimate No Ultimate to project as LS is considered Interim
It appears that the current lift station with 15 HP pumps and the 6-
inch force main will meet the future demands beyond the year 2040.
If the flow rates increase beyond the projected year 2040 flow rate,
the two 15 HP pumps can accommodate up to an additional 435
RECs. This station was designed and constructed as an interim lift
station and is expected to be converted to a trunk sewer line
manhole and drain down to Lift Station I. Therefore, no lift station
upgrades should ever be warranted.
5. Lift Station #7 (Magnolia Landing)
a. Existing Capacity
Lift Station #7 currently serves the development of Magnolia Landing
and a portion of Otsego Preserve. The lift station will also service an
area to the east of these developments to MacAllister Avenue. The
lift station has an ultimate sewer shed of just under 150 acres.
This lift station consists of a 28-foot deep, 8-foot diameter wet well.
Currently there are two 7.2 HP submersible pumps operating. A 6-
inch force main approximately 3,350 feet long traverses a 30-foot
crest on its way to tie into a manhole at the southern edge of Lift
Station #4’s service area.
From the pump system curves, each 7.2 HP pumps can pump about
255 GPM through the existing 6-inch force main.
The typical design for a duplex lift station is for one to match the peak
flow rate expected at the lift station at any hour of the day, this station
currently has capacity for an average daily flow of 105,000 GPD.
19
b. Projected Flow Rates
The projected flow rates to the Magnolia Landing Lift Station are:
2020 11,500 GPD
2030 30,000 GPD
2040 100,000 GPD
Ultimate 152,600 GPD
It appears that the current lift station with 7.2 HP pumps and the 6-
inch force main will meet the future demands to near the year 2040.
When the flow rates increase beyond the 95,000 GPD the pumps
may have to be increased slightly in size.
6. Lift Station No. #9 (Grenins)
a. Existing Capacity
Lift Station #9 currently serves the development of Grenins 2nd
Addition. The lift station was constructed due to poor soils and high-
water table not being able to support planned septic systems after
development had occurred. The lift station has an ultimate sewer
shed of only 13 acres.
This lift station consists of a 16-foot deep, 4-foot diameter wet well.
Currently there are two 3 HP submersible grinder pumps operating.
A 3-inch force main approximately 2,300 feet in length traverses a 23-
foot crest on its way to tie into a manhole at the northern edge of Lift
Station 6’s service area.
From the pump system curves, one 3 HP pump can pump about 70
GPM through the existing 3-inch force main.
The typical design for a duplex lift station is to match the peak flow
rate expected at the lift station at any hour of the day, this station
currently has capacity for an average daily flow of 25,000 GPD
b. Projected Flow Rates
The projected flow rates to the Lift Station #9are:
2020 1,225 GPD
2030 2,100 GPD
2040 2,100 GPD
Ultimate 2,100 GPD
It appears that the current lift station with 3 HP pumps and the 3-inch
force main will exceed the projected ultimate fully developed service
area for this lift station.
20
PROPOSED WEST WASTE WATER COLLECTION SYSTEM
1. Establish Proposed West Lift Station Districts
Using the natural ridgeline basin approach, augmented by the limitations of the grid
property system, four additional individual sanitary sewer Lift Station Districts were
identified for the foreseeable future. An overall view of these LS Districts is shown
on Exhibit No.3, “Lift Station District Map”.
The details of the trunk sanitary sewer system, such as pipe length and size,
proposed invert elevation, and approximate top of the manhole elevations are
shown in Exhibit No.4. Exhibit No. 4 includes an index map showing the overlay of
the fourty-nine 1” = 200’ scale maps for help in locating particular sections of the
sanitary sewer system.
Lift Station W is deemed a long-term facility and is not analyzed beyond the gravity
pipe network and potential volume of sanitary sewer that may someday be
generated. Design of the this lift station and gravity trunk sewer lines were not
included in the analysis of this report.
A total of five lift stations, consisting of one existing lift station, one interim lift
station, two proposed lift stations, and one long term lift station will discharge into
trunk gravity sewer lines that flow into existing Lift Station #3 at the W-WWTF.
Existing Lift Station #4 and proposed Lift Station B pump directly to the W-WWTF,
with existing Lift Station #7 draining into Lift Station #4.
PROPOSED WEST LIFT STATIONS
Lift Station B (Otsego Creek North)
Lift Station B has a service area of a little over 1,000 acres and is bound by
Labeaux Avenue (CSAH 19) on the west, Nashua Avenue on the east, 80th
Street on the south, and 95th Street (CSAH 39) on the north.
This lift station is proposed to be a 44-foot deep, 12-foot diameter wet well.
The lift station will eventually need three 40 HP pumps. These pumps will
lift sewage through an 8-inch and a 10-inch force main that are to be
approximately 10,000 feet in length and overcome 74-foot crest on its way
to the W-WWTF. Much of the length of the 8-inch and 10-inch force mains
have been constructed during development. Only 2,500 feet of the length
remains to be installed. The service area is guided for institutional (Middle
and Elementary Schools) and low-density residential land uses by the 2012
Comprehensive Plan. This lift station should be assessed for an on-site
generator as flow volumes increase.
21
Lift Station H (I-94)
Lift Station H is anticipated to be the eighth lift station added to the City
system in the future. Lift Station H has a service area of a just under 500
acres and is located south of I-94, west of Kadler Avenue. This lift station
will drain into a manhole on the west edge of Lift Station #3’s service area.
This lift station is proposed to be a 42-foot deep, 10-foot diameter wet well.
The lift station will be a du-plex consisting of two 10 HP pumps. These
pumps will lift sewage through a 6-inch and an 8-inch force main that are
approximately 800 feet in length and overcome 14-foot crest on its way to a
manhole at the edge of Lift Station #3’s service area. The service area of
Lift Station H is guided low density residential and industrial land uses by
the 2012 Comprehensive Plan.
Lift Station I (CSAH 39)
Lift Station I has a service area of nearly 1,300 acres and is located south
of 95th Street (CSAH 39) just east Large Court. This lift station will drain
into a trunk manhole on the east edge of Labeaux Avenue (CSAH 19) at
CROSS STREET and drain into Lift Station #3.
This lift station is proposed to be a 31-foot deep, 12-foot diameter wet well.
The lift station will be a tri-plex eventually consisting of three 50 HP pumps.
These pumps will lift sewage through a 14-inch force main that will be
approximately 14,000 feet long and overcome 79-foot crest on its way to a
manhole within Lift Station #3’s service area. The service area of Lift
Station I is guided for low density residential land uses, with minor areas of
commercial, office, and the potential of some institutional land uses. Lift
Station 6 (Riverwood National) already exists and will eventually become a
manhole and gravity drain to proposed Lift Station I. This lift station should
be assessed for an on-site generator as flow volumes increase.
IV. FUNDING OF TRUNK SEWER
A. Adequacy of SAC fees for Funding Sanitary Sewer Extensions
In accordance with the policy statements of the Comprehensive Plan, as new
land is developed, the extension of sanitary sewer will be performed and
financed by the developers. The developer will be required to install the
complete the sewer system to serve their development, as well as make
provisions for future connections servicing other adjacent properties. The cost
of the additional sewer system provisions that benefit other properties beyond
the current development is referred to as trunk oversizing or depth credits,
which the City will reimburse back to the developer through the development
agreement.
22
Usually, the typical residential development will involve only gravity sewer line
extensions. However, some developments may require a new sanitary lift
station and force main as well. The trunk oversizing cost that is eligible for
reimbursement from the Sanitary Sewer Utility Fund are calculated on Table 5.
The City will determine the cost of the lateral sewer facilities that would serve
just the development needs and subtract that from the actual cost of
construction to determine oversizing or depth costs, otherwise known as trunk
costs.
1. General Allocation of Sanitary Access Charge (SAC) and Sewer
Connection Charge (SCC) Fee Revenue.
Under the current method, the City collects the $2,641 SAC fee for each
RECs within a new development. The City later collects a $7,924 SCC
fee per REC when the building permit for each lot is obtained. These
funds are earmarked to pay for construction of the following:
a) Construction of or major upgrading of lift stations.
b) Installation of force mains and trunk sanitary sewer lines
c) Trunk oversizing or depth credits to developers.
d) WWTF expansions or upgrades
V. RECOMMENDED PROJECTS
For this report, projects that may be constructed during the next 20 years are outlined
as shown in Table No. 6, Recommended Capital Improvement Program. These
projects along with WWTF expansions and upgrades will need to be evaluated to
determine the proper amount of the SAC and SCC fees. Adjustments to that amount
can be made annually using the Engineering News Record Construction Cost Index to
adjust for inflation and changes in materials costs and labor.
VI. RECOMMENDED CAPITAL IMPROVEMENT PROGRAM
The total capital outlay for the projects expected to be performed between 2020 and
2040 are summarized in Table No. 6. In addition, the expected revenue from
collection of SAC fees is estimated for each time period in the project schedule.
The results are that the expected SAC fees are sufficient to cover all of the proposed
trunk sewer collection facility improvements through 2040 and still leave an
accumulated balance for future trunk sewer collection projects. It should be noted that
there are many contingencies that may come up in the next twenty years that may
require additional use of these fund balances.
It is recommended that the City review the estimated project costs on an annual basis.
It is also wise to review the SAC fee structure to maintain a positive fund balance. As
with any projection of growth from past history, the City should constantly re-evaluate
the actual rate of development occurring in the City and corresponding actual sewer
usage rates in GPD.
APPENDIX
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EXHIBIT 1
0 0.5 10.25 Miles
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FUTURE LAND USE00.5 10.25
Miles É
LEGEND
Planning Districts
Rural
Rural Residential
LD Residential (Large Lot)
LD Residential
LD/MD Residential
MD/HD Residential
Mixed Use
Commercial
Office
Industrial
Public/Quasi Public
K:\cad_eng\PROJECTS\GIS\TPC\Otsego\Comprensive Plan 2012\Future Land Use Map
DISCLAIMER:This product is for informational purposes and may not have beenprepared for, or be suitable for legal, engineering, or surveyingpurposes. Users of this information should review or consult theprimary data and information sources to ascertain the usabilityof the information.
TPC
COMPREHENSIVE PLAN 2012
ADOPTED: 10 December 2012
AMENDMENTS:Resolution 2015-64 adopted 26 October 2015Resolution 2017-20 adopted 13 March 2017Resolution 2018-49 adopted 23 July 2018Resolution 2021-XX adopted XX January 2021
EXHIBIT 2
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EXHIBIT 3
0 0.5 10.25 Miles
^_LIFT STATION WASTE WATER TREAMENT FACILITY
EXISTING EXTENT OF SEWER SERVICE DISTRICTSEAST/WEST BOUNDARY LINE
LS6
LSI
LSB
LS3
LSH
LSW
LS9
LS4
LS7 LSG
LSD
LSE LSY
LSZ
LSA
LS1
LS8
LSF
LS5
LS2
LSX
LSC
I
N
D
E
X
M
A
P
S
LSW LSH LS6
A
L
S
3
L
S
4
L
S
B
L
S
6
L
S
E
L
S
G
L
S
7
L
S
D
L
S
9
L
S
C
LS4 LSBL
S
E
L
S
Y
L
S
Z
L
S
8
L
S
1
L
S
F
L
S
2
L
S
5
L
S
X
L
S
A
L
S
G
LS7
L
S
D
L
S
C
LSI
L
S
Z
L
S
Y
E
X
H
B
I
T
4
D
E
T
A
I
L
E
D
M
A
P
S
LSY LSZ
L
S
Z
L
S
Z
L
S
1
LS1
LSBLSB
L
S
E
L
S
Y
L
S
Y
L
S
Z
LSY
L
S
Z
L
S
1
L
S
1
L
S
1
L
S
1
L
S
8
LSB
L
S
E
L
S
Y
L
S
1
L
S
1
LSC
LSY
L
S
1
L
S
1
L
S
8
LS4
L
S
E
L
S
D
L
S
D
LSD
L
S
1
L
S
1
LSCLSC
L
S
1
LS1
LS4LS4
L
S
D
L
S
G
L
S
G
LSGLSG LSD
L
S
1
L
S
A
L
S
C
L
S
1
L
S
A
L
S
1
LSA
L
S
F
LSF
L
S
5
LS7LSG
LSG
L
S
A
L
S
A
LSA
L
S
1
L
S
F
L
S
5
L
S
2
L
S
X
LSFL
S
5
L
S
5
L
S
2
LS
X
L
S
5
LS5
L
S
6
L
S
9
L
S
9
L
S
I
LS6
L
S
I
L
S
B
L
S
I
LSILSB
L
S
Y
L
S
I
L
S
6
L
S
B
L
S
I
LS6
L
S
3
L
S
3
L
S
I
L
S
B
LSB
L
S
E
L
S
I
L
S
3
LSI
L
S
3
L
S
B
LS3
L
S
3
L
S
4
LSB
L
S
4
L
S
E
L
S
3
L
S
3
LSH
L
S
3
L
S
4
L
S
4
L
S
D
L
S
D
L
S
H
LSW
L
S
4
L
S
7
L
S
G
L
S
H
L
S
W
LS4
L
S
7
L
S
G
1
EXHIBIT 5
Proposed Lift Station Wet
Well Geometry
ADF = 784 gpm
Pumping Rate = 2276 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 7709 Gallons
Pick Wet Well Diameter = 16.0 Ft
Pick Wet Well Cycle = 5.5 Vert. Ft
Volume in Cycle = 8272 Gallons 0.93198757 5.127841707
Vertical Datum Used:
Wet well Dia. = 16.0 Ft
Top Elev= 870.50
Gnd Elev= 870.00
SS Invert In= 848.00 Alarm = 845.50
Lag On 2 = 844.50
Lag On = 843.50
Lead On = 842.50
Pumps Off = 837.00
Bottom Invert Elev* = 833.00
*As required for complete submergence
OK
Determine Wet well Diameter
NAVD 88
Determine Wet Well Invert & Float Elevations
Cycle Time & Wet Well Geometry
Lift Station A
Target Cycles Per Hour
OK
OK
ADF = 330 gpm
Pumping Rate = 1078 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 3435 Gallons
Pick Wet Well Diameter = 12.0 Ft
Pick Wet Well Cycle = 4.5 Vert. Ft
Volume in Cycle = 3807 Gallons 0.902239669 4.061591414
Vertical Datum Used:
Wet well Dia. = 12.0 Ft
Top Elev= 922.50
Gnd Elev= 922.00
SS Invert In= 892.00 Alarm = 890.00
Lag On 2 = 889.00
Lag On = 888.00
Lead On = 887.00
Pumps Off = 882.50
Bottom Invert Elev* = 878.50
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station B
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 176 gpm
Pumping Rate = 616 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 1886 Gallons
Pick Wet Well Diameter = 8.0 Ft
Pick Wet Well Cycle = 5.0 Vert. Ft
Volume in Cycle = 1880 Gallons 1.00307822 5.017259982
Vertical Datum Used:
Wet well Dia. = 8.0 Ft
Top Elev= 932.50
Gnd Elev= 932.00
SS Invert In= 908.00 Alarm = 906.00
Lag On 2 = 905.00
Lag On = 904.00
Lead On = 903.00
Pumps Off = 898.00
Bottom Invert Elev* = 894.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station C
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 126 gpm
Pumping Rate = 456 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 1368 Gallons
Pick Wet Well Diameter = 8.0 Ft
Pick Wet Well Cycle = 4.0 Vert. Ft
Volume in Cycle = 1504 Gallons 0.909452087 3.639163902
Vertical Datum Used:
Wet well Dia. = 8.0 Ft
Top Elev= 940.50
Gnd Elev= 940.00
SS Invert In= 911.00 Alarm = 910.00
Lag On 2 = 909.00
Lag On = 908.00
Lead On = 907.00
Pumps Off = 903.00
Bottom Invert Elev* = 899.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station D
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 110 gpm
Pumping Rate = 401 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 1197 Gallons
Pick Wet Well Diameter = 8.0 Ft
Pick Wet Well Cycle = 4.0 Vert. Ft
Volume in Cycle = 1504 Gallons 0.796162069 3.18583497
Vertical Datum Used:
Wet well Dia. = 8.0 Ft
Top Elev= 912.50
Gnd Elev= 912.00
SS Invert In= 892.00
Alarm = 890.00
Lag On = 889.00
Lead On = 888.00
Pumps Off = 884.00
Bottom Invert Elev* = 880.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station E
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 122 gpm
Pumping Rate = 441 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 1324 Gallons
Pick Wet Well Diameter = 8.0 Ft
Pick Wet Well Cycle = 4.0 Vert. Ft
Volume in Cycle = 1504 Gallons 0.880181235 3.522036869
Vertical Datum Used:
Wet well Dia. = 8.0 Ft
Top Elev= 862.50
Gnd Elev= 862.00
SS Invert In= 849.00
Alarm = 847.00
Lag On = 846.00
Lead On = 845.00
Pumps Off = 841.00
Bottom Invert Elev* = 837.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station F
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 324 gpm
Pumping Rate = 1060 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 3374 Gallons
Pick Wet Well Diameter = 10.0 Ft
Pick Wet Well Cycle = 6.0 Vert. Ft
Volume in Cycle = 3525 Gallons 0.957339229 5.746175774
Vertical Datum Used:
Wet well Dia. = 10.0 Ft
Top Elev= 948.50
Gnd Elev= 948.00
SS Invert In= 917.50
Alarm = 915.00
Lag On = 914.00
Lead On = 913.00
Pumps Off = 907.00
Bottom Invert Elev* = 903.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station G
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 347 gpm
Pumping Rate = 1126 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 3601 Gallons
Pick Wet Well Diameter = 10.0 Ft
Pick Wet Well Cycle = 6.5 Vert. Ft
Volume in Cycle = 3819 Gallons 0.943007902 6.131835416
Vertical Datum Used:
Wet well Dia. = 10.0 Ft
Top Elev= 961.50
Gnd Elev= 961.00
SS Invert In= 934.00
Alarm = 931.50
Lag On = 930.50
Lead On = 929.50
Pumps Off = 923.00
Bottom Invert Elev* = 919.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station H
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
ADF = 937 gpm
Pumping Rate = 1906 gpm
Time = 15.0 min.
Cycles Per Hour = 4.0
Check Cycles Per Hour:
Check Cycles Per Hour:
Required Volume = 7145 Gallons
Pick Wet Well Diameter = 14.0 Ft
Pick Wet Well Cycle = 6.5 Vert. Ft
Volume in Cycle = 7484 Gallons 0.954709382 6.207923376
Vertical Datum Used:
Wet well Dia. = 14.0 Ft
Top Elev= 890.50
Gnd Elev= 890.00
SS Invert In= 877.00 Alarm = 875.50
Lag On 2 = 874.50
Lag On = 873.50
Lead On = 872.50
Pumps Off = 866.00
Bottom Invert Elev* = 862.00
*As required for complete submergence
OK
NAVD 88
Determine Wet Well Invert & Float Elevations
Lift Station I
Cycle Time & Wet Well Geometry
Target Cycles Per Hour
OK
OK
Determine Wet well Diameter
1
EXHIBIT 6
Proposed Pump Selection
Table 1
Population Projection
2012 Otsego Comprehensive Plan Minnesota State Demographer
2000 2010 2020 2030 2019
Households 2,062 4,736 6,800 10,000 6,254
Population 6,389 13,571 19,040 28,000 18,130
Building Permit Data 2010-2020 2010-2019 2015-2019
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 TOTAL Mean/Yr TOTAL Mean/Yr
Single family 73 58 140 184 176 181 205 210 274 292 374 1793 179 1162 232
Townhouse 3 6 12 6 14 26 8 8 75 8 54 11
Multiple Family 142 97 170 239 24 239 48
Total 73 58 143 190 188 187 219 352 300 397 552 2107 211 1455 291
Updated Household and Population Forecast
10-Year Growth Rate
2020 2030 2040
Households 6,806 8,913 11,823
Population 19486 25402 33104
5-Year Growth Rate
2020 2030 2040
Households 6,806 9,716 13499
Population 19486 27691 37797
Notes:
Building Permit Data used to estimate 2020 population
10-Year growth household projection rate assumed to increase to 263 du./year between 2030-2040
5-year household growth projection rate assumed to increase by +/- 30% between 2030-2040
DATE: 10 Nov 2020
SOURCE: City of Otsego (TPC)
Actual Projected Estimates
Table 2E
East WWTF
Lift Station Summary
Sanitary Sewer REC's
LIFT STATION DISTRICT TOTAL
ACRES
WETLAND OR UN-
DEVELOPABLE
AREAS
DEVELOPABLE
ACRES
EXISTING
LARGE LOT-
LOW DENSITY
RESIDENTIAL
ACRES
(1.0
REC'S/AC.)
DEVELOPABLE
EXISTING
LARGE LOT-
LOW DENSITY
RESIDENTIAL
ACRES
(1.0 REC'S/AC.)
RURAL
TRANSITION
LARGE LOT-
LOW DENSITY
RESIDENTIAL
ACRES
(INITIALLY 1.0
REC / 10 AC.,
ULTIMATELY 2.5
REC/ AC.)
DEVELOPABLE
RURAL
TRANSITION
LARGE LOT- LOW
DENSITY
RESIDENTIAL
ACRES
(INITIALLY 1.0
REC / 10 AC.,
ULTIMATELY 2.5
REC/ AC.)
PUBLIC/
QUASI
PUBLIC-
SCHOOLS,
PARKS , CITY
SERVICES-
2.5 REC'S
PER ACRE
DEVELOPABLE
PUBLIC/ QUASI
PUBLIC-
SCHOOLS,
PARKS , CITY
SERVICES- 2.5
REC'S PER
ACRE
OFFICE
(6 REC'S PER
ACRE)
DEVELOPABLE
OFFICE
(6 REC'S PER
ACRE)
INDUSTRIAL
ACRES
( 6 REC'S/
AC.)
DEVELOPABLE
INDUSTRIAL
ACRES
( 6 REC'S/ AC.)
COMMERCIAL
ACRES
(6 REC'S / AC.)
DEVELOPABLE
COMMERCIAL
ACRES
(6 REC'S / AC.)
HIGH /
MEDIUM
DENSITY
RESIDENTIAL
ACRES
(7-12
REC'S/AC.)
DEVELOPABLE
HIGH /
MEDIUM
DENSITY
RESIDENTIAL
ACRES
(7-12
REC'S/AC.)
MEDIUM / LOW
DENSITY
RESIDENTIAL
ACRES (3-
6 REC'S/AC.)
DEVELOPABLE
MEDIUM / LOW
DENSITY
RESIDENTIAL
ACRES
(3-6 REC'S/AC.)
LOW DENSITY
RESIDENTIAL
ACRES
(2.5 REC'S/AC.)
DEVELOPABLE
LOW DENSITY
RESIDENTIAL
ACRES
(2.5 REC'S/AC.)
TOTAL
ACRES
SERVED
DEVELOPABLE
ACRES SERVED
TOTAL
REC'S
SERVED
1,037
499
LS8 56 16.8 39 11 8 1 1 24 17 19 13 1 1 56 39 190
LSF 356 106.8 249 142 99 17 12 197 138 356 249 1,001
LSX 130 39 91 34 24 96 67 130 91 311
LIFT STATION #1 EXISTING QUADAY AVE.
LIFT STATION #Y WILSON PERSERVE
LIFT STATION #Z MISSISSIPPI SHORES
LIFT STATION #8 EXISTING WATERFRONT
LIFT STATION #B PRAUGHT
LIFT STATION #C NASHUA CENTRAL
LIFT STATION #D NASHUA NORTH
LIFT STATION #5 EXISTING RIVERPLACE
LIFT STATION #F RIVER ROAD
LIFT STATION #A DARKENWALD
LIFT STATION #G NASHUA SOUTH
LIFT STATION #2 EXISTING RIVER POINTE
LIFT STATION #X AUTUMN WOODS
TOTAL TO EAST WWTP 8952 2685.6 6,266 0 0 63 44 444 164 131 92 1,271 890 461 323 647 453 611 428 5,324 3,727 8,952 6,119 23,876
9,2071,9262,7527551,0782543633084400272389137196921311,926825.62,752LS1 1011448110
18 1,013
753
709 1,031 722
1,804
722 13
177 413LSZ 41590 29 8 6 2 1 539 377 590 413
420135193102146334713557.9193LSC
1,0362874101632331161653468287123410
94537854035350437825162540
LSD
LSE 36
91135450533047246354151.5505LS5 1927
3,9229371,547606865141201681852641,547LSA 2091,083
24 2,77646366146334439627
315126181126180112754.3181LS2
LSY 1,031 309.3
198.3661LSG
464.1
East WWTF
Lift Station Summary
Forcemain Sizing
3/3/2021
LIFT STATION DISTRICT
LS8
LSF
LSX
LIFT STATION #1
LIFT STATION #Y
LIFT STATION #Z
LIFT STATION #8
LIFT STATION #B
LIFT STATION #C
LIFT STATION #D
LIFT STATION #5
LIFT STATION #F
LIFT STATION #A
LIFT STATION #G
LIFT STATION #2
LIFT STATION #X
TOTAL TO EAST WWTP
LS1
LSZ
LSC
LSD
LSE
LS5
LSA
LS2
LSY
LSG
AVERAGE
DAILY
FLOW GPD
DISCHARGE
RECEIVED
FROM OTHER
LINE
SEGMENTS
OR PUMP
STATIONS
TOTAL
COMBINED
AVERAGE
DAILY
FLOW RATE
POPULATION
EQUIVALENT
( 1,000'S)
PEAK
FACTOR
PEAK FLOW
RATE GPD
Pump
Design
Avg (gpm)
Average
Design
Flow (cfs)
Peak
Design
Flow (gpm)
Peak
Design
Flow
(cfs)
FORCE
MAIN
PIPE
DIAMETE
R
Area
(SF)
Peak
VELOCITY
(>2 and
<5)
Velocity
(>1 and
<3)
10.75 0.63 16.01352 6.29219
15.17 1.2545 8.041416 3.15971
Both 1.8845 5.35322 2.10344
21 2.4041 4.196286 0.16395
All 4.2886 2.352336 0.9243
8 0.3489 4.79361 1.40023
6 0.1963 8.521974 2.4893
6 0.1963 3.865191 1.03918
4 0.0872 8.696681 2.33816
181,545 181,545 1.82 3.62 656,848 126.07 0.28 456.14 1.02 6 0.1963 5.178549 1.43129
4 0.0872 11.65173 3.2204
87,281 87,281 0.87 3.84 334,926 60.61 0.14 232.59 0.52 4 0.0872 5.941195 1.54827
33,259 33,259 0.33 4.06 134,996 23.10 0.05 93.75 0.21 3 0.0491 4.257207 1.04884
8 0.3489 3.955918 1.12969
6 & 8 0.5451 2.531788 0.723
10 0.5451 2.531788 0.723
8 0.3489 2.908467 0.80374
6 0.1963 5.170608 1.42887
6 & 8 0.5451 1.861419 0.51439
6 0.1963 4.756954 1.30381
4 0.0872 10.70315 2.93356
8 0.3489 2.675787 0.73339
6 & 6 0.3925 2.378477 0.6519
4 & 4 0.1744 5.351573 1.46678
6 0.1963 8.97 2.63755
10 0.5451 3.23 0.94952
Both 0.7414 2.38 0.69818
175,114 175,114 1.75 3.63 635,653 121.61 0.27 441.43 0.98 6 0.1963 5.01 1.38059
12 0.785 6.67 2.31051
16 1.3956 3.75 1.29966
8 0.3489 15.00 5.19865
8 & 12 & 16 2.5294 2.07 0.71706
18 1.7663 2.96 1.02689
8 & 18 2.1151 2.47 0.85751
8 0.3489 7.02 2.15454
8 & 8 0.6978 3.51 1.07727
6 0.1963 3.26 0.86341
4 & 6 0.2835 2.26 0.59774
6 & 6 0.3925 1.63 0.4317
4 0.0872 7.33 1.94267
54,390 54,390 0.54 3.96 215,120 37.77 0.08 149.39 0.33 3 0.0491 6.78 1.71523
4,178,291 - 4.50 -
10.09 4,527.89 3.96 ######6,520,159 2.54 25.62 2,561,965 950,661 1,611,304
1.67 750.65 0.49 219.27 1,080,929 3.42 3.16
0.76 340.46
315,744 315,744
0.20 91.53 490,262 3.72 1.32 131,810 131,810
1.38 619.47 0.39 176.90 892,035 3.50 2.55 254,739 181,239 73,500
1.01 455.45 0.28 125.86 655,841 3.62 1.81 181,239 181,239
0.93 419.01 0.26 114.84 603,373 3.65 1.65 165,375 165,375
1.76 790.31 0.52 232.32 1,138,050 3.40 3.35 334,548 175,114 159,434
5.23 2,349.26 1.81 814.07 3,382,940 2.89 11.72 1,172,264 485,835 686,429
2.45 1,098.71 0.75 337.39 1,582,145 3.26 4.86 485,835 485,835
0.64 287.04 0.17 76.05 413,332 3.77 1.10 109,515 54,390 55,125
S:\Municipal\AOTSEGO\642 MASTER SAN STUDY\Table 2E, 2W, 3E & 3W - SUB-DISTRICT USAGE 2
Table 2W
West WWTF
Lift Station Summary
Sanitary Sewer REC's
LIFT STATION DISTRICT TOTAL
ACRES
WETLAND OR UN-
DEVELOPABLE AREAS
DEVELOPABLE
ACRES
EXISTING
LARGE LOT-
LOW DENSITY
RESIDENTIAL
ACRES
(1.0
REC'S/AC.)
DEVELOPABLE
EXISTING
LARGE LOT-
LOW DENSITY
RESIDENTIAL
ACRES
(1.0
REC'S/AC.)
RURAL
TRANSITION
LARGE LOT- LOW
DENSITY
RESIDENTIAL
ACRES
(INITIALLY 1.0
REC / 10 AC.,
ULTIMATELY 2.5
REC/ AC.)
DEVELOPABLE
RURAL
TRANSITION
LARGE LOT- LOW
DENSITY
RESIDENTIAL
ACRES
(INITIALLY 1.0
REC / 10 AC.,
ULTIMATELY 2.5
REC/ AC.)
PUBLIC/ QUASI
PUBLIC- SCHOOLS,
PARKS , CITY
SERVICES- 2.5
REC'S PER ACRE
DEVELOPABLE
PUBLIC/ QUASI
PUBLIC- SCHOOLS,
PARKS , CITY
SERVICES- 2.5
REC'S PER ACRE
OFFICE ( 6
REC'S PER
ACRE)
DEVELOPABLE
OFFICE ( 6 REC'S
PER ACRE
INDUSTRIAL
ACRES
( 6 REC'S/ AC.)
DEVELOPABLE
INDUSTRIAL
ACRES
( 6 REC'S/ AC.)
COMMERCIAL
ACRES
(6 REC'S / AC.)
DEVELOPABLE
COMMERCIAL
ACRES
(6 REC'S / AC.)
HIGH /
MEDIUM
DENSITY
RESIDENTIAL
ACRES
(7-12
REC'S/AC.)
DEVELOPABLE
HIGH /
MEDIUM
DENSITY
RESIDENTIAL
ACRES
(7-12
REC'S/AC.)
MEDIUM / LOW
DENSITY
RESIDENTIAL
ACRES
(3-6
REC'S/AC.)
DEVELOPABLE
MEDIUM / LOW
DENSITY
RESIDENTIAL
ACRES
(3-6
REC'S/AC.)
LOW
DENSITY
RESIDENTIAL
ACRES
(2.5
REC'S/AC.)
DEVELOPABLE
LOW DENSITY
RESIDENTIAL
ACRES
(2.5 REC'S/AC.)
TOTAL
ACRES
SERVED
DEVELOPABLE
ACRES
SERVED
TOTAL
REC'S
SERVED
LS9 13 3.9 9 0 13 9 0 0 0 0 0 0 0 13 9 33
LS7 150 45 105 0 0 3 2 0 0 0 48 34 74 52 25 18 150 105 872
LIFT STATION 3
LIFT STATION B
LIFT STATION I
LIFT STATION 6 RIVERWOOD NATIONAL - INTERIM
LIFT STATION 9
LIFT STATION H
LIFT STATION W
LIFT STATION 4
LIFT STATION 7 MAGNOLIA LANDING
TOTAL TO W WWTf 7,116 2134.8 4,981 0 0 2,057 1,440 139 97 463 324 887 621 484 339 327 229 306 214 2,453 1,717 7,116 4,981 23,932
281 1,976 1,383
SW CORNER
MARTIN FARMS
WWWTF
OTSEGO CREEK NORTH
C.S.A.H. 39
GRENINS
I-94
181 130 91 65 46 402 7,390
928
LS6 629 188.7 440 0 628 440
1,469 440.7 1,028 0 1,326
0 0
258
70 49 77 54
LSI
233 163 826 578020144229
1,077 323.1 754 0
LS3
LSB
1,976 592.8 1,383
0 0 17 12 913 639 1,077 754 2,735
0 19 13 0 124 87 0 0 0 1,469 1,028 4,173
1 1 0 0 0 0 0 0 629 440 1,573
2,5823494991031470243453752232148211000349149.7499LSH
36695136921320340000009540.8136LSW
4,2108171,16758483410515078111192720290817350.11,167LS4 111600
Table 3E
East WWTF
Lift Station Summary
Sanitary Sewer Flows and
Forcemain Sizing
LIFT STATION DISTRICT
TOTAL
REC'S
SERVED
AVERAGE
DAILY
FLOW GPD
DISCHARGE
RECEIVED
FROM OTHER
LINE
SEGMENTS
OR PUMP
STATIONS
TOTAL
COMBINED
AVERAGE
DAILY
FLOW RATE
POPULATION
EQUIVALENT
( 1,000'S)
PEAK
FACTOR
PEAK FLOW
RATE (GPD)
Pump
Design Avg
(gpm)
Average
Design
Flow (cfs)
Peak
Design
Flow (gpm)
Peak
Design
Flow
(cfs)
FORCE
MAIN PIPE
DIAMETER
Area
(SF)
Peak
VELOCITY
(>2 and
<5)
Velocity
(>1 and
<3)
10.75 0.63 16.0135 6.29219
15.17 1.255 8.04142 3.15971
Both 1.884 5.35322 2.10344
21 2.404 4.19629 0.16395
All 4.289 2.35234 0.9243
8 0.349 4.79361 1.40023
6 0.196 8.52197 2.4893
6 0.196 3.86519 1.03918
4 0.087 8.69668 2.33816
1,037 181,545 181,545 1.82 3.62 656,848 126.07 0.28 456.14 1.02 6 0.196 5.17855 1.43129
4 0.087 11.6517 3.2204
499 87,281 87,281 0.87 3.84 334,926 60.61 0.14 232.59 0.52 4 0.087 5.9412 1.54827
LS8 190 33,259 - 33,259 0.33 4.06 134,996 23.10 0.05 93.75 0.21 3 0.049 4.25721 1.04884
8 0.349 3.95592 1.12969
6 & 8 0.545 2.53179 0.723
10 0.545 2.53179 0.723
8 0.349 2.90847 0.80374
6 0.196 5.17061 1.42887
6 & 8 0.545 1.86142 0.51439
6 0.196 4.75695 1.30381
4 0.087 10.7031 2.93356
8 0.349 2.67579 0.73339
6 & 6 0.393 2.37848 0.6519
4 & 4 0.174 5.35157 1.46678
6 0.196 8.97 2.63755
10 0.545 3.23 0.94952
Both 0.741 2.38 0.69818
LSF 1,001 175,114 - 175,114 1.75 3.63 635,653 121.61 0.27 441.43 0.98 6 0.196 5.01 1.38059
12 0.785 6.67 2.31051
16 1.396 3.75 1.29966
8 0.349 15.00 5.19865
8 & 12 & 16 2.529 2.07 0.71706
18 1.766 2.96 1.02689
8 & 18 2.115 2.47 0.85751
8 0.349 7.02 2.15454
8 & 8 0.698 3.51 1.07727
6 0.196 3.26 0.86341
4 & 6 0.283 2.26 0.59774
6 & 6 0.393 1.63 0.4317
4 0.087 7.33 1.94267
LSX 311 54,390 - 54,390 0.54 3.96 215,120 37.77 0.08 149.39 0.33 3 0.049 6.78 1.71523
LIFT STATION #1
LIFT STATION #Y
LIFT STATION #Z
LIFT STATION #8
LIFT STATION #B
LIFT STATION #C
LIFT STATION #D
LIFT STATION #5
LIFT STATION #F
LIFT STATION #A
LIFT STATION #G
LIFT STATION #2
LIFT STATION #X
TOTAL TO EAST WWTP 23,876 4,178,291 - - - 4.50 -
LS1 9,207 1,611,304 950,661 2,561,965 25.62 2.54 6,520,159 1,779.14 3.96 4,527.89 10.09
LSY
1,804 315,744
-
315,744 3.16
753 131,810 131,810 1.32
3.42 1,080,929 219.27 0.49 750.65 1.67
3.72 490,262 91.53 0.20 340.46 0.76
LSZ
LSC 420 73,500 181,239 254,739 2.55 3.50 892,035 176.90 0.39 619.47 1.38
LSD 1,036 181,239 - 181,239 1.81 3.62 655,841 125.86 0.28 455.45 1.01
LSE 945 165,375 - 165,375 1.65 3.65 603,373 114.84 0.26 419.01 0.93
LS5 911 159,434 175,114 334,548 3.35 3.40 1,138,050 232.32 0.52 790.31 1.76
LSA 3,922 686,429 485,835 1,172,264 11.72 2.89 3,382,940 814.07 1.81 2,349.26 5.23
LSG 2,776 485,835 - 485,835 4.86 3.26 1,582,145 337.39 0.75 1,098.71 2.45
LS2 315 55,125 54,390 109,515 1.10 3.77 413,332 76.05 0.17 287.04 0.64
Table 3W
West WWTF
Lift Station Summary
Sanitary Sewer Flows and
Forcemain Sizing
LIFT STATION DISTRICT
TOTAL
REC'S
SERVED
AVERAGE
DAILY
FLOW
(GPD)
DISCHARGE
RECEIVED
FROM OTHER
LINE
SEGMENTS
OR PUMP
STATIONS
TOTAL
COMBINED
AVERAGE
DAILY FLOW
RATE
POPULATION
EQUIVALENT
( 1,000'S)
PEAKING
FACTOR
PEAK FLOW
RATE GPD
Pump
Design
Avg (gpm)
Avg
Design
Flow
(cfs)
Peak
Design
Flow (gpm)
Peak
Design
Flow (cfs)
FORCE
MAIN PIPE
DIAMETER
Area (SF)
Peak
VELOCITY
(>3 and
<10)
Avg
Velocity (>1
and <3)
16 1.396 7.83 3.13
8 0.349 31.31 12.51
10 0.545 20.04 8.00
12 0.785 13.92 5.56
All 3.075 3.55 1.42
12 & 10 1.330 8.21 3.28
12 & 8 1.134 9.63 3.85
12 & 16 2.181 5.01 2.00
10 & 8 0.894 12.22 4.88
10 & 16 1.941 2.85 2.25
12 & 10 & 8 1.679 6.51 2.60
12 & 10 & 16 2.726 4.01 1.60
8 & 16 1.744 6.26 2.50
10 & 8 & 16 2.290 4.77 1.91
8 0.349 6.92 2.12
10 0.545 4.43 1.36
10 & 8 0.894 2.70 0.83
10 & 10 1.090 2.22 0.68
8 0.349 13.23 4.48
10 0.545 8.47 2.87
10 & 8 0.894 5.16 1.75
10 & 10 1.090 4.23 1.43
12 1.788 2.58 0.87
14 2.181 2.12 0.72
8 & 12 2.137 2.16 0.73
10 & 12 2.333 1.98 0.67
8 & 14 2.529 1.82 0.62
4 0.087 17.27 4.98
6 0.196 7.68 2.21
4 & 6 0.283 5.31 1.53
LS9 33 5,688 - 5,688 0.06 4.30 24,474 3.95 0.01 17.00 0.04 3 0.049 0.77 0.18
8 0.349 7.39 2.29
10 0.545 4.73 1.46
10 & 8 0.894 2.89 0.89
6 & 8 1.744 1.48 0.46
3 0.049 7.91 2.02
4 0.087 4.45 1.14
10 0.545 7.59 2.52
14 1.068 3.87 1.29
10 & 14 1.614 2.56 0.85
LS7 872 152,600 - 152,600 1.53 3.67 560,675 105.97 0.24 389.36 0.87 6 0.196 4.42 1.20
West WWTF Total
LIFT STATION #3
LIFT STATION #E
LIFT STATION #6
LIFT STATION #6A
LIFT STATION #9
LIFT STATION #H
LIFT STATION #W
LIFT STATION #4
LIFT STATION #7
TOTAL TO WEST WWTP 23,932 4,188,170 - 4,188,170 41.88 2.34 9,787,538
LS3 1,958.47 4.36 4,903.36 10.92
LSB
7,390 1,293,233 1,526,963 2,820,195 7,060,83928.20 2.50
2.422,735 478,625 - 478,625 4.79
LS6
3.26 1,561,531 332.38 0.74 1,084.40
702.19 1.56 2,071.38 4.62
LS6A
4,173 730,275 280,875 1,011,150 2,982,79110.11 2.95
1.511,573 275,188 5,688 280,875 2.81
LSH
3.47 973,669 195.05 0.43 676.16
358.20 0.80 1,157.87 2.58
LSW
2,582 451,763 64,050 515,813 1,667,3365.16 3.23
0.3936664,050 - 64,050 0.64
LS4
3.92 250,850 44.48 0.10 174.20
3.01 2,672,585 617.60 1.38 1,855.96 4.144,210 736,750 152,600 889,350 8.89
Table 4
Existing Lift Station Summary
Existing
Lift
Station
WWTF Depth
(ft)
Diameter
(ft)
Existing
Pumps
(HP)
Existing
Peak
Flow
Rate
(GPM)
Existing
FM in
Use (In)
Existing LS
Capacity
(GPD)
Existing
LS
Capacity
(REC)
Existing
LS (GPD)
Existing
Use
(REC)
Ultimate
Peak Flow
Rate
(GPM)
Ultimate
FM (In)
Ultimate
LS
Capacity
(GPD)
Ultimate
LS
Capacity
(REC)
Projected
Ultimate
Capacity
(REC)
Projected
Year of
Ultimate
Capacity
1 E 42 12 40,50,50 650 12 335,000 1914 335,000 1914 4525 12,16,21 2,562,000 14,640 14640 2040+
2 E 40 10 12,12 250 6 92,400 528 51,210 293 450 6,6 180,000 1,029 0 2040+
3 W 33.5 12 40,40,20 830 16 412,000 2354 412,000 2354 4634 8,10,12,16 2,780,000 15,886 16115 2040+
4 W 39 12 60,60,60 935 10 479,150 2738 152,300 870 1856 10,14 977,800 5,587 0 2040+
5 E 42 10 25,25,25 440 6 176,000 1006 32,600 186 1750 6,10 850,000 4,857 0 2040+
6 W 29 8 15,15 290 6 105,000 600 21,000 120 290 6 105,000 600 see LS I see LS I
7 W 28 8 7,7 255 6 95,000 543 11,500 66 390 6 152,600 872 5082 2040+
8 E 11.5 4 3,3 90 3 130,000 743 27,000 154 90 3 130,000 743 0 2040+
9 W 16 4 3,3 70 3 25,000 143 1,225 7 6 3 25,000 143 7 2030
Note:The Lift Stations are color coded to match the Lift Station borders of Exhibit 3
Table 5
Proposed Lift Station Trunk Cost Summary
Force Main
(DIA)(Length)
Lift Station
(Depth, DIA)
Extra Depth &
Trunk Size Sub Totals per Lift
$183,500.00 $1,668,578.13 $1,604,520.00 $7,229,852.81
(8")(2600')(37', 16')
$3,773,254.69
(12" & 16")(12100')C
$1,438,218.75 $1,233,806.25 $1,936,865.00 $4,608,890.00
(8" & 10")(10000')(44', 12')
$234,743.75 $769,278.13 $500,600.00 $1,504,621.88
(6" & 8")(1800')(25', 8')
$480,646.09 $909,793.75 $484,950.00 $1,875,389.84
(6" & 8")(3550')(41', 8')
$517,428.13 $780,850.00 $572,110.00 $1,870,388.13
(8")(6800')(32', 8')
$130,596.88 $787,462.50 $223,810.00 $1,141,869.38
(6")(1800')(25', 8')
$387,657.81 $1,023,859.38 $612,850.00 $2,024,367.19
(8" & 8")(2850)(45', 10')
$611,009.38 $985,837.50 $550,104.00 $2,146,950.88
(6" & 8")(800')C (42', 10')
$1,801,906.25 $1,166,028.13 $2,235,392.00 $5,203,326.38
(14")(14000)(31', 12')
TOTALS $9,558,961.72 $9,325,493.75 $8,721,201.00 $27,605,656.47
W B Otsego Creek North 3 (40)
E A Rice Lake 3 (50)
COST (2021)
PR
O
P
O
S
E
D
L
I
F
T
S
T
A
T
I
O
N
S
WWTF LS ID Name Number of
Pumps (HP)
E C Oakwood
E D
E E Nashua North
Nashua Central
E F River Road
E G Nashua South
W
W
H
I CSAH 39
I-94
2 (20)
2 (15)
2 (10)
3 (50)
2 (7.5)
2 (10)
2 (15)
Table 6
Recommended Capital Improvement Program
2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
LS1 9,207 1914 7293 21%70 110 110 110 50 55 55 55 55 55 55 50 50 50 50 50 50 50 50 40 3134 34%
LS2 315 211 104 67%20 20 20 20 20 311 99%
LS3 7,390 2354 5036 32%55 100 100 100 90 90 90 90 65 65 65 40 40 40 40 40 40 40 40 40 3624 49%
LS4 4,210 870 3340 21%55 75 75 75 85 90 90 90 65 65 65 40 40 40 40 40 40 40 40 40 2060 49%
LS5 911 186 725 20%35 65 65 65 65 70 70 70 70 70 70 901 99%
LS6 135 120 15 89%5 5 130 96%
LS7 872 66 806 8%15 20 25 25 25 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 476 55%
LS8 190 154 36 81%0 5 5 5 0 169 89%
LS9 33 7 26 22%0 5 12 37%
E 125 200 200 200 135 125 125 125 125 125 125 50 50 50 50 50 50 50 50 40
W 125 200 200 200 200 200 200 200 150 150 150 100 100 100 100 100 100 100 100 100
LSA 3,922 0 3922 0%65 75 75 75 75 75 50 50 50 50 50 50 50 50 50 40 930 24%
LSB 2,735 0 2735 0%50 50 50 100 100 100 100 100 100 100 100 100 1050 38%
LSC 420 0 420 0%25 100 100 100 100 100 100 100 100 95 920 219%
LSD 1,036 0 1036 0%25 25 2%
LSE 945
LSF 1,001
LSG 2,776
LSH 2,582
LSI 4,173
E 125 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200
W 125 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200
Total REC's 250 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 7850
Sewer Fee Generations 10,656.00$ per REC w/ 1.0% inflation 0.01 2,664,000$ 4,305,024$ 4,348,074$ 4,391,555$ 4,435,471$ 4,479,825$ 4,524,623$ 4,569,870$ 4,615,568$ 4,661,724$ 4,708,341$ 4,755,425$ 4,802,979$ 4,851,009$ 4,899,519$ 4,948,514$ 4,997,999$ 5,047,979$ 5,098,459$ 5,149,444$ 92,255,403$
LSA 101,023$ 1,934,087$ 166,967$ 168,637$ 170,323$ 172,026$ 173,747$ 175,484$ 177,239$ 179,011$ 180,801$ 182,609$ 190,549$ 3,658,548$ 7,631,051$
LSB 148,645$ 2,972,895$ 209,735$ 211,832$ 213,950$ 216,090$ 218,251$ 220,433$ 222,638$ 224,864$ 227,113$ 229,384$ 5,315,829$
LSC 61,322$ 1,155,392$ 55,297$ 55,850$ 56,409$ 56,973$ 57,543$ 58,118$ 58,699$ 59,286$ 59,879$ 60,478$ 1,795,247$
LSD 89,949$ 1,632,741$ 58,587$ 1,781,277$
SAC 1,868,192$ 1,875,872$ 1,888,352$ 1,902,576$ 1,538,752$ 1,465,192$ 1,464,883$
Biosolids 377,056$ 1,011,030$ 1,010,603$ 1,011,072$ 1,010,423$ 1,010,671$ 1,010,802$ 1,010,818$ 1,010,717$ 1,010,500$ 1,010,167$ 1,010,718$ 1,010,142$ 1,010,449$ 1,010,628$ 1,010,680$ 1,010,604$ 1,010,400$ 1,011,069$ 1,010,599$ 19,579,148$
WWWTF Exp - Liquids 276,794$ 1,702,813$ 1,705,895$ 1,702,673$ 1,702,825$ 1,701,588$ 1,703,585$ 1,698,159$ 1,700,200$ 1,700,185$ 1,698,375$ 1,694,720$ 1,694,113$ 1,691,791$ 1,693,003$ 1,692,654$ 1,690,710$ 27,450,083$
WWWTF Access 1,200,000$ 1,200,000$
EWWTF Exp - Liquids 452,121$ 2,263,430$ 2,261,109$ 2,262,320$ 2,261,971$ 2,260,028$ 11,760,979$
Cash Balance - 2020 11,769,048$ 12,187,800$ 13,605,922$ 14,954,018$ 13,021,044$ 13,037,560$ 13,166,990$ 13,194,288$ 11,905,594$ 13,364,054$ 13,768,985$ 15,322,514$ 16,916,069$ 18,553,260$ 20,235,429$ 21,697,299$ 21,394,608$ 21,143,291$ 20,656,379$ 15,437,976$ 15,507,017$
Total REC's
Available
REC's
Used REC's Remaining
% used
Assumed Allocation of REC's