HomeMy WebLinkAboutItem 06.iComprehensive Water Plan Update
City of Lakeville, Minnesota
SEH No. LAKEV 123875
November 12, 2013
Comp Water Plan 2013 Nov 12.docx
November 13, 2013 RE: Comprehensive Water Plan Update
City of Lakeville, Minnesota
SEH No. LAKEV 123875
Mr. Zachary Johnson
City Engineer
City of Lakeville
20195 Holyoke Ave.
Lakeville, MN 55044
Dear Mr. Johnson:
Enclosed please find the most recent Comprehensive Water Plan Update for the City of Lakeville,
Minnesota. The primary emphasis of this study was to plan for future water system facilities required to
serve areas of anticipated growth in the City. These facilities included wells, water storage, and trunk
water main. The existing computer model of the water distribution system was updated and used for the
analysis. The system was evaluated with respect to pressure, flow, pipe friction, and fire flow availability.
Extended period simulations were also used to analyze system operations.
We greatly appreciate the help provided by City staff. As always, it has been a pleasure working with the
City. The staff’s experience and knowledge of the system and cooperative spirit proved very helpful in
creating and calibrating the model as well as providing other valuable information.
We will be available to review this report with you at your request. If you have any questions, please
don’t hesitate to call me or Miles Jensen at 651.490.2000
Sincerely,
Chad T. Katzenberger, PE
Project Engineer
amc
s:\ko\l\lakev\123875\4-prelim-dsgn-rprts\comp water plan 2013 nov 12.docx
Short Elliott Hendrickson Inc. | 3535 Vadnais Center Drive | Saint Paul, MN 55110-5196
SEH is an equal opportunity employer | www.sehinc.com | 651.490.2000 | 800.325.2055 | 888.908.8166 fax
Draft Comprehensive Water Plan Update
City of Lakeville, Minnesota
SEH No. LAKEV 123875
November 13, 2013
I hereby certify that this 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.
John D. Chlebeck, PE
Date: August 7, 2013 Lic. No.:47125
Reviewed by: Miles Jensen August 7, 2013
Date
Short Elliott Hendrickson Inc.
3535 Vadnais Center Drive
Saint Paul, MN 55110-5196
651.490.2000
Comprehensive Water Plan Update
City of Lakeville, Minnesota
SEH No. LAKEV 123875
November 13, 2013
I hereby certify that this 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.
Chad T. Katzenberger, PE
Date: ovember 13, 2013 Lic. No.:46613
N
Reviewed by: Miles Jensen ovember 13, 2013
N
Date
Short Elliott Hendrickson Inc.
3535 Vadnais Center Drive
Saint Paul, MN 55110-5196
651.490.2000
Executive Summary
This report serves as support for the current capital improvement planning process being completed by the
City of Lakeville. The focus of the report is to analyze existing water utility facilities, and to anticipate
future system needs based on anticipated growth within the City. This report is an update on the last
Comprehensive Water Plan completed in 2008. The analysis at that time incorporated growth projections
that have since seen significant revision. In addition, the plan for water system facilities to serve future
growth has been refined from a perspective of maximizing the use of existing infrastructure, optimizing
service to future water system customers, and minimizing future capital costs where possible.
The Lakeville water system consists of infrastructure components that perform supply, treatment, storage
and distribution functions. This study evaluates system needs in each category (with the exception of water
treatment) to meet existing and projected water use. Water treatment is dealt with in greater detail in a
separate water treatment plant facility evaluation that is being completed concurrently with this
Comprehensive Water Plan Update.
Existing facilities include:
17 water supply wells pumping from bedrock aquifers with a total supply capacity of
22 million gallons per day (MGD)
One central water treatment facility including gravity filtration for iron and manganese removal
One below grade concrete water storage reservoir (clearwell) with a capacity of 3.1 million gallons (MG)
located at the water treatment facility, including a high service pumping facility that pumps from the
clearwell to the distribution system
Five elevated water storage tanks located on the distribution system with a total useable capacity of 4.75 MG
Approximately 300 miles of cast iron and ductile iron water distribution mains ranging in size from 6
inches to 36 inches in diameter
Three distinct pressure zones including a Normal Zone that is supplied from the water treatment plant,
and two reduced pressure zones that serve lower elevations through pressure reducing valves (PRVs)
located on the distribution system
Many water system facilities are designed by industry standard to meet maximum daily demands reliably.
Maximum daily water use on the Lakeville water system has ranged from 13.2 MGD to 20.4 MGD over
the previous five years. The amount of water use varies with population and land use patterns, as well as
with environmental factors such as precipitation and temperature. Often peak water use is driven by
summer irrigation demand.
The population for Lakeville in 2012 is estimated at 57,048. The population is projected to increase to an
ultimate level of approximately 88,800 between 2030 and 2035 by current estimates. This results in a projected
maximum daily water use of potentially 31.435 MGD. New development is expected to drive much of the
increase in population and water use in Lakeville. This report includes recommendations for infrastructure
improvements to reliably serve projected new development and corresponding increases in water demand.
Recommended improvements in this report include:
Ten new water supply wells
One new elevated water storage tank
Trunk distribution mains to serve new development
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota
Table of Contents
Letter of Transmittal
Certification Page
Executive Summary
Page
Table of Contents
1.0 Introduction ............................................................................................................. 1
2.0 Existing System ...................................................................................................... 3
2.1 Existing Facilities .............................................................................................. 3
2.2 Water Demands................................................................................................ 7
2.3 Demand Distribution ......................................................................................... 7
3.0 Hydraulic Analysis of the Distribution System ..................................................... 9
3.1 Computer Model Setup and Calibration ............................................................ 9
3.2 System Pressures ............................................................................................ 9
3.3 Pipe Velocities and Friction Loss .................................................................... 12
3.4 Extended Period Simulation........................................................................... 12
3.5 Current Available Fire Flow ............................................................................ 14
4.0 Expansion Areas and Projected Demands .......................................................... 15
4.1 Area Served ................................................................................................... 15
4.2 Elevations Served ........................................................................................... 15
4.3 Population Trends .......................................................................................... 15
4.4 Projected Growth ............................................................................................ 18
4.5 Land Use Based Demand Projections ............................................................ 19
5.0 Recommendations ................................................................................................ 20
5.1 Water Supply Wells ........................................................................................ 20
5.1.1 Ipava Avenue Transmission Main ....................................................... 21
5.2 Storage ........................................................................................................... 24
5.2.1 Elevated Storage Location .................................................................. 25
5.3 Trunk Water Main ........................................................................................... 32
5.4 Distribution System Back-Pressure with Expansion
of High Service Pumping Facilities................................................................. 32
5.5 System Pressures After Improvements ........................................................... 33
5.6 Available Fire Flows After Improvements ........................................................ 33
6.0 Capital Improvement Plan .................................................................................... 37
6.1 Estimated Cost of Water System Improvements ............................................. 37
6.1.1 Trunk Water Main Oversize Costs....................................................... 38
6.1.2 Wells ................................................................................................... 38
6.1.3 Elevated Water Storage Tank ............................................................. 38
6.1.4 Raw Water Transmission Lines ........................................................... 38
6.1.5 Water Treatment Facility Improvements .............................................. 38
6.2 Capital Improvement Plan Timeline ................................................................ 38
6.3 Trigger Chart .................................................................................................. 39
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page i
Table of Contents (Continued)
List of Tables
Table 1 – Existing Pressure Zones ...................................................................................... 1
Table 2 – Existing Well Supply Facilities ............................................................................. 3
Table 3 – Existing Storage Facilities.................................................................................... 4
Table 4 – Water Demand History ........................................................................................ 7
Table 5 – Recommended Single-Family Residential Fire Flows ........................................ 14
Table 6 – Population and Household Trends ..................................................................... 18
Table 7 – Metropolitan Council Population Projections ...................................................... 18
Table 8 – Population-Based Demand Projections ............................................................. 19
Table 9 – Land Use-Based Demand Projections ............................................................... 20
Table 10 – Well Construction Schedule ............................................................................. 21
Table 11 – Elevated Storage Needs .................................................................................. 25
Table 12 – Existing High Service Pump Controls as Modeled ........................................... 26
Table 13 – Modified Maximum Day High Service Pump Controls as Modeled................... 27
Table 14 – Modified Average Day High Service Pump Controls as Modeled ..................... 27
Table 15 – Trunk Water Main Extensions .......................................................................... 37
Table 16 – Water Supply and Storage Facilities ................................................................ 37
Table 17 – Raw Water Transmission Main ........................................................................ 37
Table 18 – Capital Improvement Plan Timeline ................................................................. 38
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page ii
Table of Contents (Continued)
List of Figures
Figure 1 – Current Available Service Area ........................................................................... 2
Figure 2 – Existing Water Supply System ............................................................................ 5
Figure 3 – Existing Water Distribution System ..................................................................... 6
Figure 4 – Typical Residential Demand Distribution Graph .................................................. 8
Figure 5 – Existing Average Day Pressures ...................................................................... 10
Figure 6 – Existing Peak Hour Pressures .......................................................................... 11
Figure 7 – Extended Period Simulation Results for the Existing System ............................ 13
Figure 8 – Maximum Day Available Fire Flows .................................................................. 16
Figure 9 – Ultimate Distribution System............................................................................. 17
Figure 10 – Hydraulic Analysis of Raw Water Transmission Main on Ipava Avenue .......... 22
Figure 11 – Ultimate Raw Water Supply System ............................................................... 23
Figure 12 – Extended Period Simulation Results for the
Future Tower at Cherryview Park ......................................................... 29
Figure 13 – Extended Period Simulation Results for the
Future Tower at Highview Avenue & 190th Street ................................ 30
Figure 14 – Extended Period Simulation Results with Modified Piping to New Tower ........ 31
Figure 15 – Distribution System Hydraulic Impacts from Added High Service Pumping .... 32
Figure 16 – Ultimate Average Day Pressures .................................................................... 34
Figure 17 – Ultimate Peak Hour Pressures ....................................................................... 35
Figure 18 – Ultimate Available Fire Flow ........................................................................... 36
Figure 19 – Water System Capital Improvement Trigger Chart ......................................... 40
List of Appendices
Appendix A Raw Water System Analysis
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page iii
November 2013
Comprehensive Water Plan Update
Prepared for City of Lakeville, Minnesota
1.0 Introduction
The Lakeville water distribution system serves most of the businesses and residents within
the city limits of Lakeville. There are some properties served by individual or private
community wells. This is especially true for areas identified for future expansion. Other areas
of the City are supplied with water by the City of Burnsville. The current available service
area of the water distribution system is represented in Figure 1.
The Lakeville water distribution system currently consists of 17 wells, one water treatment
plant, one below-ground storage reservoir, one at-grade storage standpipe, four elevated
storage tanks, and approximately 300 miles of water distribution piping. The system is based
on three pressure zones as listed in Table 1.
Table 1–Existing Pressure Zones
Static Pressure
Pressure Zone Tower Overflow Elevations Served
Range (psi)
Normal Zone 1230 949 to 1170 26 to 122
Valley Park 1121 919 to 1020 44 to 88
Air Lake 1109 939 to 987 52 to 74
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City of Lakeville, Minnesota Page 1
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2.0 Existing System
2.1 Existing Facilities
Water is supplied to the City of Lakeville’s water system from 17 wells that draw from the
Prairie du Chien-Jordan and Franconia-Ironton-Galesville aquifers. The total operating
capacity of the City’s wells is 15,350 gpm (22.10 MGD), with a firm supply operating
capacity of 14,250 gpm (20.52 MGD). Firm capacity is defined as the system capacity minus
the capacity of the largest pump. This is the capacity that can be provided consistently, even
during maintenance when one well pump might be out of service.
Supply and storage system components are listed in Tables 2 and 3. The well capacities listed in
Table 2 indicate an operating supply capacity that is less than the design capacity of each well.
This is due to the interaction of the wells when pumped simultaneously. During peak summer
operating conditions, the well production rates are reduced by interference-related drawdown.
Table 2–Existing Well Supply Facilities
Facility Design Supply Operating Supply Operating Supply
Treated
Name Capacity (gpm) Capacity (gpm) Capacity (MGD)
Well 2 Yes 900 850 1.22
Well 3*** No 1,300 1,000 1.44
Well 4 Yes 1,250 1,000 1.44
Well 6 Yes 1,200 1,000 1.44
Well 7*** No 1,200 0 0.00
Well 8 Yes 1,580 1,000 1.44
Well 9 Yes 1,450 1,000 1.44
Well 10 Yes 1,400 1,000 1.44
Well 11 Yes 1,300 1,000 1.44
Well 12 Yes 1,400 1,000 1.44
Well 13 Yes 1,400 1,000 1.44
Well 14 Yes 1,550 1,000 1.44
Well 15 Yes 1,500 1,000 1.44
Well 16 Yes 1,500 1,000 1.44
Well 17 Yes 1,400 1,000 1.44
Well 18** Yes 600 400 0.58
Well 19 Yes 1,300 1,100 1.58
Total 22,230 15,350 22.10
Firm Capacity 14,250 20.52
** Well 18, completed in the Franconia-Ironton-Galesville Aquifer, will be utilized to the largest extent possible
to reduce pumping from Prairie du Chien - Jordan Aquifer.
*** Wells 3 and 7 are designated for emergency use only; Well 7 is taken out of capacity calculation due to
potential interference with private wells
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 3
Table 3Existing Storage Facilities
–
Facility Name Overflow TypeStorage Usable *
Elevation Capacity (MG) Storage (MG)
Clearwell 1069 Ground 3.1 3.1
Airlake 1109 Hydropillar 0.5 0.5
Fairfield 1230 Hydropillar 0.75 0.75
North Park 1230 Spheroid 1.0 1.0
Dakota Heights 1230 Standpipe 2.0 1.0
Valley Park 1121 Composite 1.5 1.5
Composite
Total 8.85 7.85
Total Elevated 4.75
* Usable storage at Dakota Heights is shown as 1.0 since pressures in the area are below 35 psi static when it is
full. Homes in this area typically are on booster pumps/tank systems which the City participates 50/50 on cost.
A map of the water supply system, including locations of wells and the water treatment plant
that supply the City, is shown in Figure 2.
The water treatment plant for the City of Lakeville provides iron and manganese removal
through a gravity filtration system. The design capacity of the filters is 20 MGD, with
room for expansion to 30 MGD with four additional filter cells. A filter loading study was
recently conducted, indicating that the loading rate on the existing filters could safely be
increased to 26.5 MGD.
Filtered water is stored in a below-grade clearwell prior to pumping into the distribution
system at the high service pumping station. The high service pumping station contains four
pumps currently, including two pumps with 4 MGD (2825 gpm) design capacity, one pump
with 8 MGD (5700 gpm) design capacity, and one pump with 14 MGD (8300 gpm) design
capacity. The existing firm pumping capacity of the facility is 16 MGD (11,350 gpm), with
the largest pump out of service.
The Lakeville water distribution system is comprised of water mains ranging in size from 6
inches to 30 inches in diameter. There are five gravity-operated water storage tanks on the
distribution system, in addition to the below-grade water storage clearwell at the water
treatment facility. Distribution facilities, including water mains, storage tanks, and pressure
reducing valves, are mapped in Figure 3.
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2.2 Water Demands
The Lakeville water utility records indicate that in 2012, the average daily (AD) water
demand for the complete system was 6.9 MG (4,792 gpm). The maximum day (MD) demand
for 2012 was 18.9 MGD (13,125 gpm). Water demands from the period of 2007 - 2012 are
summarized in Table 4. The highest maximum day demand rate was experienced in 2007 at
20.4 MGD. It is thought that conservation activities, as well as a downturn in the housing
market, are contributing factors to the reduction in demand since 2007.
Table 4Water Demand History
–
Maximum
Average Average Per Maximum
Peaking Day Per
Population Day CapitaDay
Year Factor Capita
Estimate Demand Demand Demand
(MD/AD) Demand
(MGD) (gpcd) (MGD)
(gpcd)
2007 53,829 7.2 134 20.4 2.8 379
2008 54,328 6.7 123 20.2 3.0 372
2009 55,772 6.6 118 17.1 2.6 307
2010 55,954 5.8 104 13.2 2.3 236
2011 56,534 6.3 111 15.0 2.4 265
2012 57,048 6.9 121 18.9 2.7 331
2.3 Demand Distribution
Water demands are variable throughout the day and the season. The heaviest demand
conditions typically occur during a MD demand scenario in the summer, when outdoor water
use is at its highest level.
Over the course of a given day, water uses often follow a diurnal demand distribution. Figure
4 represents a typical demand distribution graph for residential water use. Commercial and
industrial uses are usually more constrained and predictable. The residential demand graph
depicts low water demand during the late evening and early morning periods. As the
morning progresses, there is an increase in demand as automatic sprinkler systems are
operated in conjunction with increased home water use. During late morning to early
afternoon there is a slight recovery prior to a second peak use in the early evening.
Most water systems are designed to meet the maximum daily demand rate with supply
facilities such as wells, treatment processes, and high service pumping facilities. Storage
reservoirs are used to supplement the supply of treated water during the peak usage hours
within each day. During lower usage periods, the system is able to produce water in excess of
the demand. This excess is used to fill the storage reservoirs. When the demand rate exceeds
the production rate, the stored water in the reservoirs is used to make up for the deficit.
Based on accounts of utility operations staff in Lakeville, the demand distribution in
Lakeville may have a higher peak in the morning than in the evening, due to the
predominance of automatic sprinkler systems in the city. The storage tanks in Lakeville are
also observed to lose a greater quantity of water during the morning peak use period.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 7
Figure 4 – Typical Residential Demand Distribution Graph
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
12:00 AM2:00 AM4:00 AM6:00 AM8:00 AM10:00 AM12:00 PM2:00 PM4:00 PM6:00 PM8:00 PM10:00 PM12:00 AM
TIME OF DAY
Taken from AWWA M32, Computer Modeling of Water Distribution Systems, 2005,
American Water Works Association
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 8
3.0 Hydraulic Analysis of the Distribution System
3.1 Computer Model Setup and Calibration
The computer model was originally constructed during an earlier water system
comprehensive planning process. SEH refined the model in the last Comprehensive Water
Plan in 2008, and conducted calibration at that time. For this plan update, five hydrant flow
tests were conducted to supplement earlier calibration data and verify model calibration.
InfoWater by Innovyze was used for this analysis.
All utility owned pipes 6 inches in diameter and larger were included in the original model.
Current utility distribution system mapping in GIS was used for this plan update to make the
model reflect current system conditions. The demands were updated based on historic
pumping data. Elevation data were assigned to the model using 2-foot contour information
supplied by the City, based on available LIDAR.
Demands were assigned to model junction nodes based on historical demands as recorded by
the utility. Demands were assigned evenly across the system, and later adjusted in order to
calibrate the extended period simulation results to system operations as recorded by the
utility’s SCADA system.
3.2 System Pressures
Average Day (AD) pressures are depicted by pressure districts in Figure 5. The existing
system pressures for an AD demand scenario range from 24 to 121 psi. The minimum
working pressure as stated in Ten States Standards is 35 psi.
Pressures are typically lower than this near the Dakota Heights Tank where elevations are the
highest in the City limits. Homes in this area typically have in-home booster pumps/tanks to
increase the pressure to an acceptable range. The City’s current policy is to participate 50/50
in cost sharing to furnish and install these booster pumps/tanks.
The pressures calculated for a peak hour (PH) simulation are represented in Figure 6. The
change in water pressure between AD and PH demands varies over the distribution system.
The largest pressure variations observed in the model were approximately 15 psi in the
northeastern portion of the distribution system
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3.3 Pipe Velocities and Friction Loss
Pipe segments are considered potentially deficient, or most-limiting, if they have the
following conditions:
Velocities greater than 5 ft/s; and
Head losses greater than 10 ft/1000 ft.
Velocities in pipe segments are acceptable up to about 10 ft/s during emergency or extreme
demand conditions of short duration. As velocities increase, pipe friction increases and
problems with water hammer occur. This is especially true in systems with higher pressures.
We have checked the system for locations where velocities and head losses meet the above
stated conditions. There are several locations where pipe velocities exceed 5 ft/s. The
majority of these locations are near the water treatment plant as the high service pumps are
operating at peak capacity. In addition, several locations throughout the distribution system
where inconsistent sizing creates bottlenecks were also apparent. These bottlenecks also
results in head losses greater than 10 ft/1000 ft.
3.4 Extended Period Simulation
An extended period simulation (EPS) was setup in the model to check the system operation
during several consecutive days of maximum day demands. The primary purpose of this
simulation was to check for cumulative system imbalances that are not evident in standard
simulations. Tower and system supply placement and the sizes of distribution system pipe
contribute to imbalances. They also contribute to a reduced storage-replenishment rate and
the ability to refill the towers at night during low demand periods.
We have simulated a 72-hour period with three consecutive maximum day (MD) demand
conditions. The model utilizes demand pattern curves to adjust demand over the course of a
day to approximate variations in water use. Controls were set up on the high service pumps
at the water treatment plant to turn the pumps on and off based on water tower levels. The
existing controls for the high service pumps were entered into the model during the last
Comprehensive Water Plan, and are presented in Table 12, in Section 5.2.1.
The expected water surface elevations during EPS analysis indicated that there is imbalance
in the system under peak conditions. During simulated consecutive maximum day events, the
North Park Tank drains quicker than the Dakota Heights Tank. At times there is as much as a
five to ten foot difference in hydraulic grade lines. This imbalance is thought to be caused by
high peak demands in the northeastern portion of the distribution system.
The City has installed modulating valves at the water treatment plant that are designed to
direct more flow toward the North Park tank. Under peak demands, these valves have been
used to throttle plant effluent going to the west and south, which in turn directs more flow
north along Ipava Avenue.
Modeling results also seem to indicate a lag in the filling of the Fairfield tower under
peak demand conditions. Depending on the level of demand on the south end of the
system, the Fairfield tower may also have water levels that are lower than Dakota Heights
under peak demand conditions.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 12
Figure 7 – Extended Period Simulation Results for the Existing System
ExistingSystemExistingControlsMDEPS
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
1,200.00
NorthParkHGL
DakotaHeightsHGL
1,195.00
FairfieldHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
ExistingSystemExistingControlsADEPS
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
1,200.00
NorthParkHGL
DakotaHeightsHGL
1,195.00
FairfieldHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
Figure 7 depicts tank water elevation fluctuations as modeled during two different EPS
scenarios for the existing system. The first graph depicts tank water elevations under
maximum day (MD) demands. The second graph depicts tank water elevations under
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 13
average day (AD) demands. Under AD demand conditions, the towers are balanced well, and
there are no difficulties encountered in filling the tanks.
As demands continue to increase on the system as projected, the system imbalances will tend
to be exacerbated. This will be offset by additional trunk main construction to some degree.
The analysis of tank hydraulic balance for the ultimate distribution system is discussed in
more detail in Section 5.2.1, as it relates to the location of future elevated storage.
3.5 Current Available Fire Flow
The modeled fire flows were run up to a maximum of 3,500 gpm. The computer model
indicates that higher flows are available in some areas, but at some point they become
unrealistic because there are not enough hydrants or fire equipment to deliver such high rates.
The minimum fire flow available at any given point in a system should not be less than 500
gpm at a residual pressure of 20 psi. This represents the amount of water required to provide
for two standard hose streams on a fire in a typical residential area for single-family
residential dwellings with spacing between 31 to 100 feet. The distance between buildings
and the corresponding fire flow is summarized in Table 5.
Recommended Single-Family Residential Fire Flows
Table 5 –
Distance Between Needed Fire
Buildings (feet) Flow (gpm)
More than 100 500
31-100 750
11-30 1000
Less than 11 1500
The needed fire flow for commercial and industrial buildings, according to ISO, is based on
several characteristics of individual buildings such as:
Type of construction
Type of business that is using the property and materials stored
Proximity and characteristics of nearby properties
Presence or absence of a fire sprinkler system, and design of sprinkler system
While the minimum available fire flow for residential buildings with greater than 100 feet
between them should be at or above 500 gpm, typically more available flow is needed.
Needed fire flow can approach 10,000 gpm for some properties. It is not realistic for a
water distribution system to provide that amount of water for fire protection in most cases.
Therefore, those properties would need other fire protection systems to augment the water
from the distribution system.
ISO does expect communities to provide up to 3500 gpm for 3 hours where needed fire flow
is in excess of 3500 gpm. The community’s fire insurance rating can be impacted for
providing less than this where needed. These flow rates are usually necessary for high
density or industrial properties.
The computed fire flows for the current distribution system are represented in Figure 8. They
are represented by fire flow districts in gallons per minute.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 14
4.0 Expansion Areas and Projected Demands
4.1 Area Served
The Comprehensive Water Plan of 2008 considered MUSA planned expansion areas and
timelines that represented the development projections at that time. The recent economic
recession and housing market retreat have forced a reconsideration of growth projections for
Lakeville. The City is currently in the beginning stages of developing a comprehensive land
use plan. Preliminary information from that plan, along with population projections
previously developed by the Metropolitan Council for Lakeville, were considered for the
projection of future water demands that will drive water utility infrastructure investment.
It is understood that land development is currently increasing in the east-central portion of the
city (bounded by Dodd Boulevard on the west and north, Lakeville Boulevard on the south,
and the municipal boundary on the east). Preliminary land use planning includes commercial
and medium to high density residential development along the Cedar Avenue corridor
between Lakeville Boulevard and Dodd Boulevard. Outside of that corridor, it is expected
that development will be mostly low to medium density residential.
Though there are other areas for future development to the west, south, and northeast of the
current water utility service area, the vast majority of growth and water system expansion is
expected to occur in the east-central area as defined above.
4.2 Elevations Served
The expansion service areas shown in Figure 9 include land with elevations ranging from
930 to 1180. This elevation range will likely require service from both the normal and
reduced pressure zones. A portion of the expansion area west of I-35 is unable to be served
by the existing normal pressure zone. Higher elevations in this location will result in
pressures below recommended levels. If this area is served in the future, a small boosted
pressure zone including pumping station would be recommended. A minimum area to be
served by this zone is indicated in Figure 9 as “Future Boosted Pressure Zone”. However,
Service to this area is not planned for the foreseeable future.
There are also existing locations within the service area that may have less than ideal service
pressure during high demand scenarios. It is not feasible to isolate these areas into a separate
boosted pressure zone. Therefore, it has been the practice of the City to have users install booster
pumps where service pressures are below ideal (typically 50 psi). Areas where this condition is
likely to occur are indicated figure 9 and noted as “Booster Pump Service Area”. These areas
were identified based on land elevations which would result in the pressures indicated.
4.3 Population Trends
The population of the City of Lakeville has increased rapidly over the past forty years.
Population and household trends are shown in Table 6. The most recent weak housing
market has resulted in a reduction in growth since 2008. City staff have reported that
there is evidence that development may be on an increasing trend again, with an increase
in subdivision requests.
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Table 6Populationand Household Trends
–
Annual Growth
Year Population Households
Rate (%)
1970 7,196 1,883
1980 14,790 4,337 7.5%
1990 24,854 7,851 5.3%
2000 43,128 13,609 5.7%
2010 55,954 18,683 2.6%
The population estimate for 2012 was recently released by the Metropolitan Council, at
57,048. With an average annual population increase of 547 between 2010 and 2012, that is
an average annual growth rate of 1.0%.
4.4 Projected Growth
Table 7 summarizes population projections from the Metropolitan Council for the City of
Lakeville. These forecasts were adopted by the Metropolitan Council as part of the 2030
Regional Development Framework.
Table 7Metropolitan Council Population Projections
–
Average Density Average
Year Population Employees Households (People / Annual Growth
Household) Rate (%)
2020 78,400 22,945 28,400 2.76 3.4
2030 88,800 27,387 33,500 2.65 1.3
Based on the developable land in Lakeville currently, it is thought that the 2030 projected
population of 88,800 is representative of ultimate build-out and saturated development.
The City’s Economic Development department estimates that the Metropolitan Council
population projections are possibly overly aggressive. A 2% growth rate may be more
reflective of near-term growth. For the purposes of this study, we have examined a range
of potential growth bounded by the Metropolitan Council projections on the high end, and a
2% growth rate on the low end.
Based on the population projection range, water demands are projected in Table 8. These
demand projections are based on an assumed average day per capita demand rate of 118
gallons per capita per day (gpcd), which is an average of the prior 10 years, after eliminating
the highest and lowest outliers. The maximum day demand is projected using a peaking
factor (maximum day demand to average day demand ratio) of 3.0, which is the highest of the
previous five years. The projected demand rates represent a high water use year for the
projected population, and likely a summer with low rainfall.
Using a relatively high demand projection rate, though within reason, is good practice for
infrastructure planning. A capital improvement plan based on such projections will allow for
the City to reliably meet the future demands of the water system.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 18
Table 8 Population-Based Demand Projections
–
Projected Projected
Projected Projected
Average Day Maximum Day
Projected Average Maximum
Projected
Demand - Demand -
Population Day Day
Population -
Year Metropolitan Metropolitan
Metropolitan - 2% Demand - Demand -
Council Council
Council Growth 2% Growth 2% Growth
Population Population
(MGD) (MGD)
(MGD) (MGD)
2014 64,932 7.662 22.986 59,376 7.006 21.019
2015 67,177 7.927 23.781 60,576 7.148 21.444
2016 69,422 8.192 24.575 61,799 7.292 21.877
2017 71,666 8.457 25.370 63,048 7.440 22.319
2018 73,911 8.721 26.164 64,321 7.590 22.770
2019 76,155 8.986 26.959 65,621 7.743 23.230
2020 78,400 9.251 27.754 66,946 7.900 23.699
2021 79,440 9.374 28.122 68,299 8.059 24.178
2022 80,480 9.497 28.490 69,679 8.222 24.666
2023 81,520 9.619 28.858 71,086 8.388 25.165
2024 82,560 9.742 29.226 72,522 8.558 25.673
2025 83,600 9.865 29.594 73,987 8.730 26.191
2026 84,640 9.988 29.963 75,482 8.907 26.721
2027 85,680 10.110 30.331 77,007 9.087 27.260
2028 86,720 10.233 30.699 78,562 9.270 27.811
2029 87,760 10.356 31.067 80,149 9.458 28.373
2030 88,800 10.478 31.435 81,769 9.649 28.946
2031 88,800 10.478 31.435 83,420 9.844 29.531
2032 88,800 10.478 31.435 85,106 10.042 30.127
2033 88,800 10.478 31.435 86,825 10.245 30.736
2034 88,800 10.478 31.435 88,579 10.452 31.357
2035 88,800 10.478 31.435 88,800 10.478 31.435
4.5 Land Use Based Demand Projections
Due to the uncertainty with growth projections and water use projections, it is useful to estimate
future water system demands from multiple perspectives to find a range of potential outcomes.
In addition to the population-based method used in the previous section, projected land uses
were also examined for this plan, and water demands projected based on an assumed unit
demand per area for varying land uses. The method used is summarized in Table 9.
Since the City is currently in the process of developing a land use plan, the values in Table 9
for acreage for each category of development are estimated. The unit demands for each type
of development are typical values, and were chosen here to match the City’s current water
and sewer planning documents.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 19
Table 9 Land Use-Based Demand Projections
–
verage
A
UnitsPersons UnitUnit
Day
Area
per per Demand Demand
(ac) Demand
Acre Unit(gpd/Person) (gpd/ac)
(MGD)
Cedar Ave Commercial 80 1,200 0.096
Cedar Ave MD / HD Residential 490 7 2.56 100 1,792 0.878
South Office Park 490 1,200 0.588
South Light Industrial 105 1,200 0.126
West Commercial 70 1,200 0.084
West LD Residential 140 3 3.16 100 948 0.133
West MD / HD Residential 140 7 2.56 100 1,792 0.251
Rural / Open Space 2,000 - -
Remainder - Low Density 3,380 3 3.16 100 948 3.205
Residential
Estimated Total - Added Average Day Demand through Ultimate Development 5.360
2011 Average Day Demand 6.143
Projected Average Day Demand through Ultimate Development 11.503
Projected Maximum Day Demand through Ultimate Development (Assumes a Maximum 34.510
Day Peaking Factor of 3.0)
5.0 Recommendations
With future development, Lakeville will require additional supply, storage and trunk water
main to meet the water supply needs of its residents and businesses. Water treatment capacity
may need to be expanded in the future as well. A concurrent study is underway to evaluate the
capacity of the existing water treatment facility. This section evaluates the capacity of water
supply and distribution facilities based on current and projected water demands. The proposed
distribution system layout for the ultimate service area was presented in Figure 9.
5.1 Water Supply Wells
A community’s water supply capacity is sized to meet maximum day demands reliably. The
industry standard is to provide enough pumping capacity to meet the maximum day demand
rate with the largest pump out of service (i.e. firm capacity). Current well supply capacity in
Lakeville is 22.1 MGD, and the firm pumping capacity is 20.5 MGD. Maximum day
demands reached a peak of 20.4 MGD in 2007. That rate has fluctuated since then, but could
reach that level with the right environmental conditions to drive up water use.
Based upon the peak demand projections in Table 8, the 2007 level of per capita use
combined with the current population could drive demand above the current firm well supply
capacity. For that reason, additional capacity is recommended in the near future. It is
understood that the City is planning to initiate a well project this year. If growth continues at
the projected rate, additional wells will be needed as indicated in Table 10.
Figure 11 shows the proposed locations of future wells. A study was conducted as part of
this plan update to review potential locations for future wells along the Dodd Blvd. corridor.
That study is attached in Appendix A. It included a review of hydrogeologic conditions and
raw water transmission capacity.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 20
The findings indicate that the aquifer and transmission main should support 2-3 additional
wells along that corridor. There are potential well interference issues, and transmission main
friction losses that limit development beyond that.
The current plan is to construct additional future wells in the east central portion of the city,
extending a second raw water transmission main to transport water back to the existing water
treatment facility. The long range water system capital improvement plan set forth in this
plan includes this assumption. As the need for the transmission main, and those additional
wells, becomes more imminent, it is recommended that an aquifer pumping test be conducted
in the vicinity of proposed new wells to assess the local aquifer properties in more detail.
Well Construction Schedule
Table 10–
ea Projected Maximum Fim Capacity Future Well
Yrr
Day Demand (MGD) (MGD) Operating
2014 22.986 23.4 Wells 20, 21
2015 23.781 25.416 Wells 22, 23
2016 24.575 25.416
2017 25.370 26.568 Wells 24, 25
2018 26.164 26.568
2019 26.959 28.008 Well 26
2020 27.754 28.008
2021 28.122 29.448 Well 27
2022 28.490 29.448
2023 28.858 29.448
2024 29.226 30.888 Well 28
2025 29.594 30.888
2026 29.963 30.888
2027 30.331 30.888
2028 30.699 30.888
2029 31.067 32.328 Well 29
2030 31.435 32.328
2031 31.435 32.328
2032 31.435 32.328
2033 31.435 32.328
2034 31.435 32.328
2035 31.435 32.328
5.1.1Ipava Avenue Transmission Main
The City would also like to investigate additional wells along the transmission main that runs
north from the water treatment plant along Ipava Avenue, in order to maximize the use of
existing transmission main infrastructure prior to constructing new transmission mains to
serve new well fields. There is a potential for well interference and restrictions in existing
transmission main capacity with additional well pumping along the corridor.
There are two locations that have been identified as potential sites for new wells. One is the
current site of Well 17, at Steve Michaud Park. The other is the current site of Well 11, at
Eastview Elementary School. The hydraulic model of the raw water system was used to
analyze the effect on backpressure at the wells with the addition of new wells pumping into
the existing transmission line. Figure 10 provides the results of the hydraulic analysis.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 21
The first well simulated in each modeling scenario was a Jordan well with an estimated
capacity of 1000 gpm. The second well simulated was a FIG well with an estimated capacity
of 400 gpm.
Figure 10 – Hydraulic Analysis of Raw Water Transmission Main on Ipava Avenue
The hydraulic model indicates that one additional well pumping at 1000 gpm at Michaud Park
adds approximately 30 feet of head on the existing well pump there. A second 400 gpm well at
that location adds an additional 15 - 20 feet of head. The pump operation curve for Well 17
should be examined to evaluate the potential effect on that pump. It is possible that
interference and/or frictional back pressure on the pump could significantly reduce its capacity
or cause the pump to operate outside of the manufacturer’s recommended operating conditions.
Additional well pumping at the Eastview Elementary site is expected to have a lesser impact
on backpressure in the transmission main. The modeling results predict approximately 10
feet of additional head with one additional well pumping at 1000 gpm. A second additional
well at the site pumping 400 gpm adds approximately 5 feet of additional head.
Interference related drawdown is also expected at either site with the addition of a Jordan
well. A FIG well is not expected to interfere with the existing Jordan wells. Based on the
analysis presented in the Raw Water System Analysis in Appendix A, the interference
drawdown is estimated to be approximately 10 feet if the second well is spaced 1000 feet
from the existing well. Spacing of less than 1000 feet is not recommended for a Jordan well.
A test well is highly recommended at either location prior to proceeding with a production
well. This would allow closer examination of potential interference before investing in
production well construction.
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Given the potential for interference and transmission main limitations, it is recommended that
additional analysis be conducted prior to proceeding with any well construction that would
utilize the existing transmission main on Ipava Avenue. This includes a review of well pump
performance curves, field testing of well pump performance, and test wells to examine
aquifer performance characteristics.
For planning purposes, it is assumed in this study that one additional FIG well and one
additional Jordan well may be constructed at the Eastview Elementary site. One additional FIG
well is shown at the Michaud Park site. If an additional FIG well turns out to be viable at this
site, it could allow the City to utilize existing raw water transmission main infrastructure and
provide time to construct a new transmission main on the east side of the water treatment plant.
5.2 Storage
To determine the water storage needs of a community, average daily demands, peak
demands, and emergency needs must be considered. Table 11 shows the calculations used to
determine future water storage volume requirements for Lakeville. Water storage facilities
should be capable of supplying the desired rate of fire flow for the required length of time
during peak demands when the water system is already impacted by other uses and with the
largest supply pump out of service.
The calculations in Table 11 assume that maximum day demands are occurring on the system,
storage volume is reduced by peak demands greater than firm supply pumping rate (i.e.
equalization storage is expended), and the highest-capacity high service pump is out of service.
There is an assumption that the firm well capacity is equal to or greater than the firm pumping
capacity at the water treatment facility. It should be noted that the calculation is examining
elevated storage capacity only, since the storage capacity at the water treatment plant is
accounted for by the firm high service pumping rate that draws from the below-grade clearwell.
Because there are multiple pressure zones in Lakeville served by elevated storage, it is
important to evaluate the needs of each zone separately. In the case of Lakeville, two of the
elevated storage tanks are in reduced pressure zones (Air Lake and the CMF Composite).
Water from these tanks is not available to serve the needs of the normal pressure zone.
Table 11 indicates that there could be a shortage of elevated storage capacity to meet current
needs of the normal pressure zone. The water demands used for current needs are those
projected for 2013 based on population as discussed in Section 4 of this report.
Ultimately, the calculations in Table 11 indicate a need for an additional 1.5 million gallons
of elevated storage to serve the normal pressure zone. This could be constructed in stages, or
as a single tank. There would be significant cost savings by constructing a single tank with
1.5 million gallons in capacity.
Storage need in the reduced pressure zones (Air Lake and Valley Park) is more a function of
flow distribution than capacity, therefore individual calculations similar to those in Table 11
are not included for these zones. The reduced zones are served by multiple PRVs with ample
capacity to maintain water levels in the Air Lake and Valley Park tanks provided there is
enough storage on the system as a whole. The storage tanks on the high zone are capable of
serving the reduced zones as well. The presence of elevated storage in these zones helps to
control PRV operation and to provide a local reservoir of water for fire demands. The current
storage capacity in the reduced zones is sufficient to serve these functions through ultimate
build-out of the water distribution system.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 24
Table 11Elevated Storage Needs
–
2013 Projected Ultimate Normal Zone Normal Zone
Demand Development 2013Ultimate
A
Average Daily Water Use in gpd 7,000,000 10,478,400 4,900,000 7,335,000
B
Maximum / Average Day Ratio 3.0 3.0 3.0 3.0
Maximum Day Water Use in gpd
C
(A x B) 21,000,000 31,435,200 14,700,000 22,005,000
D
Maximum Day Water Use in gpm 14,583 21,830 10,208 15,281
Firm Pumping Supply Capacity in
E
gpm* 11,000 22,000 6,625 15,451
F
ISO Design Fire Fighting Rate in gpm 3,500 3,500 3,500 3,500
G
Fire Fighting Duration in Hours 3 3 3 3
Design Fire Fighting Volume in gal.
H
(F x G x 60min/hour) 630,000 630,000 630,000 630,000
Total Coincident Demand in gpm
I
(D + F) 18,083 25,330 13,708 18,781
Required Draft from Storage in gpm
J
(I - E) 7,083 3,330 7,083 3,330
Adjusted Fire Fighting Storage in gal
K
(G x 60 min/hr x J) 1,275,000 599,400 1,275,000 599,445
Equalization Storage in gal
L
(D x 225)** 3,281,250 4,911,750 2,296,875 3,438,281
M
Total Storage Need in gal (K + L) 4,556,250 5,511,150 3,571,875 4,037,726
N
Existing Elevated Storage in gallons 4,750,000 2,750,000
* Firm pumping capacity represents treatment facility high service pumping capacity with largest pump out of service. Calculations for
Main Zone storage use firm pumping capacity of high service pumps minus estimated demand to reduced pressure zones.
** Equalization storage volume based on estimated water use in excess of maximum day demand rate over the course of the maximum
day. Estimated here based on typical diurnal demand curve peaking.
Constructing too much storage capacity on a system can be problematic if it creates excessive water
residence times on the distribution system - especially during low demand periods. However, the
average day for Lakeville is currently in excess of the projected ultimate storage need for the
community. Because of this, water residence times are not expected to exceed recommended
values as water in the towers can be turned over on a daily basis with current operations.
It is recommended that an additional 1.5 MG storage tank be constructed to serve the main
pressure zone in the near future. Given the time it takes for planning, design, bidding, and
construction, the earliest a new elevated water storage tank could be online is likely 2016. It
is placed on the capital improvement plan later in this report as such.
5.2.1Elevated Storage Location
In addition to overall storage capacity, storage location becomes important for the hydraulic
operation of the distribution system. For example, if storage is located too far from properties with
high fire flow needs, the distribution system would need to be sized excessively in order to get the
high flow rates from the storage location to the point of use. Elevated storage tanks also are often
designed to balance hydraulically on the overall distribution system under peak operating demands.
This is the case in Lakeville, where the water levels in one tank (Dakota Heights) is used to
control operation of the high service pumps at the water treatment facility. The other
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 25
elevated tanks are filled and drained based on their hydraulic connectivity to the high service
pumps and the Dakota Heights standpipe. As discussed in Section 3.4, under high demand
conditions, the water levels in the North Park and Fairfield tanks are observed to drop below
the level of the Dakota Heights tank.
Because they are separated from the high service pumps and the Dakota Heights tank by
piping with frictional resistance, it is not possible to fill the more remote tanks as quickly
when demands are high on the system. Additional pumping tends to fill the Dakota Heights
tank first. Adding pumping capacity would therefore tend to overflow Dakota Heights before
filling the more remote tanks.
For this reason, the hydraulic balance of a future elevated tank on the normal pressure zone
should be taken into consideration. A location for the new tank should be chosen where
possible to allow equalization of water levels without having to size water mains excessively.
Two alternate locations for an elevated tank were evaluated from a hydraulic standpoint -
for hydraulic balance and the transmission of fire flows. A potential location for a new
tower was identified in Cherryview Park, located near the intersection of Dodd Blvd. and
175th St. A water tower at this location was modeled under existing system demands with
existing distribution facilities, as well as with ultimate projected demands and distribution
facilities. A second location near the intersection of Highview Ave. and 190th St. was
modeled in the existing system and ultimate system scenarios to evaluate the difference in
system hydraulic balance between the two locations.
The modeling analysis for each location included extended period simulation (EPS) under
varying system conditions. The model utilizes demand pattern curves to adjust demand over
the course of a day to approximate variations in water use. Controls were set up on the high
service pumps at the water treatment plant to turn the pumps on and off based on water tower
levels. The existing controls for the high service pumps were entered into the model during
the last Comprehensive Water Plan, and are represented in Table 12. For the purposes of this
analysis, it was assumed that Wells 3 and 7 remained off.
Because the greatest system imbalances occur under peak demand conditions, the EPS
analyses were run under both average day and maximum day demand conditions on the
system. It was assumed for all maximum day conditions that the control points were
modified to maintain water levels in the tanks near full to avoid any severe tank draining
events. The controls used in the model for this purpose are shown in Table 13.
Existing High Service Pump Controls as Modeled
Table 12–
Hydraulic Design
HSP Controlling Hydraulic Corresponding Corresponding
Grade Capacity
No.Tower Grade OnLevel On Level Off
Off (gpm)
1 Dakota Heights 1212 50 1220 58 5700
2 Dakota Heights 1222 60 1227 65 2825
3 Dakota Heights 1224 62 1229 67 2825
4 Dakota Heights 1226 64 1229 67 8300
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 26
Table 13 Modified Maximum Day High Service Pump Controls as Modeled
–
Design
HSP Hydraulic Corresponding Hydraulic Correspondin
Controlling Tower Capacity
No.Grade On Level On Grade Off g Level Off
(gpm)
1 Dakota Heights 1226 64 1229 67 5700
2 Dakota Heights 1226 64 1229 67 2825
3 Dakota Heights 1226 64 1229 67 2825
4 Dakota Heights 1226 64 1229 67 8300
Similarly, controls for average day demand conditions were modified to allow fluctuation in
tank water levels to achieve tank turn-over and prevent water stagnation. The modified
average day controls are listed in Table 14.
In an EPS analysis, the computer model generates results over time for system conditions
such as flow rates, pressures, pump status, and tower water levels. The EPS was run for three
consecutive days under maximum day demands and average day demands to observe how the
water tower levels are predicted to fluctuate. The results of the EPS analysis of each location
with the existing distribution system / demands, and with the ultimate planned distribution
system / demands, are shown in Figures 12 and 13.
The results in Figure 12 indicate that the Cherryview Park location is hydraulically disconnected
from Dakota Heights and the water treatment plant. Under existing system maximum day
demands, the Cherryview Park tank lags the Dakota Heights tank by as much as 15 feet during
high demand conditions. This is further exacerbated under the ultimate maximum day demand
conditions. Under average day demand conditions, all of the tanks equalize relatively well.
Table 14 – Modified Average Day High Service Pump Controls as Modeled
Hydraulic Design
HSP Hydraulic Corresponding
Corresponding
Controlling Tower Grade Capacity
No.Grade OnLevel On Level Off
Off (gpm)
1 Dakota Heights 1205 43 1229 67 5700
2 Dakota Heights 1210 48 1229 67 2825
3 Dakota Heights 1210 48 1229 67 2825
4 Dakota Heights 1215 53 1229 67 8300
The Highview and 190th Street location has a much greater hydraulic connection to Dakota
Heights and the water treatment plant, as indicated in Figure 13. For the existing system
maximum day demand scenario, with high service pump controls modified to keep the tanks
near full, a tank at the proposed location is observed to fill and remain full during the course
of the simulation. The tank fills quickly due to its proximity to the water treatment plant high
service pumps, and drains slowly due to its distance from system demands.
The model indicates that this situation can be fixed if the piping is in place between the water
tower and the existing distribution system along 190th Street, and between 190th Street and
195th Street east of Dodd Blvd., as shown in Figure 9. With this piping in place, a valve can
be closed in the short term between the north-south main east of Dodd Blvd. and the existing
distribution system connection point. This would force the flow of water to come from the
south, better balancing the new water tower with the existing system. The modeled tower
levels under these conditions are shown in Figure 14.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 27
With ultimate system maximum day demands, the Highview and 190th Street location tends
to track Dakota Heights closely, indicating good hydraulic balance. Therefore, a tank at this
location will tend to become better balanced on the system as demands increase to the east.
Based on the findings of the hydraulic analysis, a future elevated tank would be better situated
hydraulically near the vicinity of Highview Avenue and 190th Street. The modeling shows
potential challenges with tank operations at that location as discussed. These challenges can be
overcome through a temporary valve closure on the proposed connecting trunk main, and are
expected to correct over time with increasing demands to the east of the proposed tank location.
The alternate location considered at Cherryview Park has limitations that are more difficult to
overcome operationally, and that will be exacerbated over time as demands increase on the system.
In addition to system hydraulics, there are other important considerations when selecting a
site for an elevated water storage tank. Common considerations include the following:
Ground elevation: higher ground elevation results in a less expensive and less intrusive
elevated tank to reach the necessary hydraulic grade of the water level in the tank.
Existing water main infrastructure that can be used to connect the tank hydraulically to
the water system.
Soil conditions: water tank foundations have high loadings, and poor soil conditions
can result in significant soil correction requirements or deep foundations on piles -
either of which could add significantly to the cost of the project.
Airport structure height restrictions.
Visual impact to neighbors and / or shadowing.
Availability and cost of land.
The first two of these items were examined as part of this study. The remaining items should
be evaluated more thoroughly during preliminary design for the new water storage tank.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 28
Figure 12 – Extended Period Simulation Results for the Future Tower at Cherryview Park
ToweratCherryviewMDModifiedControlsMDEPS
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
NorthParkHGL
1,200.00
DakotaHeightsHGL
FairfieldHGL
1,195.00
CherryviewHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
ToweratCherryviewMDModifiedControls40MGDHSPUltimate
MDDemands/TrunkSystem
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
1,200.00
NorthParkHGL
DakotaHeightsHGL
1,195.00
FairfieldHGL
CherryviewHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
ToweratCherryviewADModifiedControlsExistingSystemAD
Demands
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
NorthParkHGL
1,205.00
DakotaHeightsHGL
1,200.00 FairfieldHGL
CherryviewHGL
1,195.00
1,190.00
01020304050607080
TimeofSimulation(hr)
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 29
Figure 13 – Extended Period Simulation Results for the Future
Tower at Highview Avenue & 190th Street
ToweratHighview/190thMDModifiedControlsExistingSystemMD
Demands
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
NorthParkHGL
1,200.00
DakotaHeightsHGL
1,195.00
FairfieldHGL
HighviewHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
ToweratHighview/190thMDModifiedControls40MGDHSP
UltimateMDDemands/TrunkSystem
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
NorthParkHGL
1,200.00
DakotaHeightsHGL
FairfieldHGL
1,195.00
HighviewHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
ToweratHighview/190thADModifiedControlsExistingSystemAD
Demands
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
NorthParkHGL
DakotaHeightsHGL
1,200.00
FairfieldHGL
1,195.00
HighviewHGL
1,190.00
010203040506070
TimeofSimulation(hr)
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 30
Figure 14 – Extended Period Simulation Results with Modified Piping to New Tower
ToweratHighview/190thMDModifiedControlsMDEPS
1,235.00
1,230.00
1,225.00
1,220.00
1,215.00
1,210.00
1,205.00
NorthParkHGL
1,200.00
DakotaHeightsHGL
FairfieldHGL
1,195.00
HighviewHGL
1,190.00
01020304050607080
TimeofSimulation(hr)
Ground elevation is an important factor as the height of the storage tank structure is
determined by the system hydraulic grade and the ground elevation. To function on the
normal pressure zone, the overflow hydraulic grade of the new tank needs to be set at 1230
feet. The ground elevation at Cherryview Park is approximately 1020 feet. This results in a
tower height of at least 210 feet. This is a very tall structure, which adds to the cost and the
visual impact to the surrounding neighborhood.
By comparison, the site near Highview and 190th St. has a ground elevation of approximately
1090, resulting in a tower that is 140 feet tall. The estimated cost impact of additional
structure height for a water tower is approximately $10k to $15k per foot. Therefore, the
Cherryview Park location could add $1M in construction cost to the project.
Given that system hydraulics and ground elevation favor the site near Highview and 190th
Street, it is recommended that this site be further investigated for the construction of an
elevated water storage facility. Given the difficulties posed by the Cherryview Park site, it is
recommended that the City abandon that site for an elevated tank in the normal pressure zone.
If property is identified in the area of Highview and 190th Street, further investigation is
recommended prior to final design for the tank.
To further evaluate the chosen site, soil borings are recommended along with a geotechnical
review of the soils at the site. This will help to evaluate foundation requirements for the tank,
and allow further refinement of the estimated project cost. This could be conducted as part of
preliminary design for the new tank.
In addition to the geotechnical review, a review of the site for FAA clearances should be
conducted and the permitting process started as necessary to construct the tower at the chosen
location. It is also common to have “virtual reality imaging” (VRI) of the new tower at the
site completed, along with a shadow study, to gain public acceptance of the project.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 31
5.3 Trunk Water Main
As development progresses into the expansion areas, a trunk water main system must be
constructed to deliver adequate flows for various conditions including emergency fire flow. The
majority of trunk water main improvements identified are outside of the existing service area
and should be constructed as development occurs. Figure 9 presented the proposed preliminary
routing of trunk water mains to serve future development areas. Actual main routing will
depend on a variety of local factors as individual projects progress. This map should be seen as
a recommendation for the general hydraulic capacity of the distribution system as it is extended
to serve new development. Generally speaking, the trunk main layout is comprised of a
gridded network of 24-inch, 16-inch, and 12-inch diameter water mains.
5.4 Distribution System Back-Pressure with Expansion of
High Service Pumping Facilities
Based on the analysis of the Water Treatment Facility Expansion Study that is being
completed concurrent with this study, additional pumping capacity at the water treatment
plant will be added over the course of the next 20 - 30 years. A hydraulic modeling analysis
was conducted to evaluate the impact of additional high service pumping on distribution
system pressures, which in turn impacts the performance of the high service pumps.
The hydraulic grade at the plant was calculated with incremental pumping increases to
evaluate changes. The calculations were performed in the hydraulic model under maximum
day conditions with high service pump flow rates as indicated in Figure 15. The pump
performance curves for the existing high service pumps should be reviewed to evaluate the
impact to pump performance given these expected hydraulic conditions.
Figure 15 – Distribution System Hydraulic Impacts from Added High Service Pumping
1,350.00
1,300.00
1,250.00
1,200.00
1,150.00
1,100.00
GroundElevation
HGLExistingHSPs1&2at10,000gpm
1,050.00
HGLExistingHSPs1,2,&3at13,000gpm
HGLUltimateHSPsat23,000gpm
HGLUltimateHSPsat28,000gpm
1,000.00
010002000300040005000
DistancefromWTP(ft)
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 32
5.5 System Pressures After Improvements
The future average day system pressures after all recommended improvements are
represented in Figure 16. Peak hour pressures are shown in Figure 17.
The modeling results indicate that the trunk main capacities as modeled will allow the
distribution of flow under projected peak hour demands without significant losses due to
friction. In addition, the division into pressure zones of the future expansion area in the east-
central portion of the city was designed to maintain static system pressures within acceptable
operating ranges where possible. The average day and peak hour conditions represent a range
of expected typical operating pressures.
5.6 Available Fire Flows After Improvements
The future available fire flows under maximum day demands are represented in Figure 18.
These flows represent the future expected available fire flows with all recommended
system improvements.
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6.0 Capital Improvement Plan
One of the main objectives of this study was to develop a long-range Capital Improvement
Plan (CIP) for water system facilities. The CIP provides information on the anticipated cost
and timing of future improvements.
6.1 Estimated Cost of Water System Improvements
The estimated costs of future trunk water main extensions, storage and well facilities, and raw
water main are shown in Tables 15, 16, and 17 respectively. Costs for future water treatment
facility improvements are being provided separately in a concurrent facility plan completed
by Black and Veatch.
Trunk Water Main Extensions
Table 15–
Trunk Oversize Total Trunk Oversize
Diameter (in) Length (ft)
Cost ($/ft) Cost
12 169,600 10 $1,696,000
16 46,857 30 $1,406,000
20 16,773 50 $839,000
24 190 70 $13,000
Total Trunk Oversize Estimated Cost
$3,954,000
Estimated Cost per Year if All Ultimate Water System Trunk
Water Main Constructed Between 2014 and 2035
$188,286
Water Supply and Storage Facilities
Table 16–
ea Construction ActivityEstimated Project Cost
Yr
2014 Well 20, Well 21 $1,400,000
2015 Well 22, Well 23 $1,400,000
2016 1.5 MG Main Zone Elevated Storage Tank $3,000,000
2017 Well 24, Well 25 $1,400,000
2019 Well 26 $700,000
2021 Well 27 $700,000
2024 Well 28 $700,000
2029 Well 29 $700,000
Total Estimated Costs for Water Supply and Storage
$10,000,000
Facilities
Table 17–Raw Water Transmission Main
Total Raw Water
Diameter Unit Cost
Year Well Served Length (ft) Transmission Main
(in)($/ft)
Cost
2015 Wells 26 / 27 24 3,000 $130 $390,000
2019 Wells 26 / 27 24 5,745 $130 $746,850
2024 Well 28 16 2,700 $90 $243,000
2029 Well 29 16 2,400 $90 $216,000
Total Estimated Costs for Raw Water Transmission Main $1,595,850
The cost estimates are reported in 2013 dollars. The costs can be related to the value of the
Engineering News Record (ENR) Index for Construction Costs (U.S. 20 City Average 1913 =
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 37
100) of approximately 9542 (June 2013). Future changes in this index can be used as a
preliminary gauge of cost changes in the proposed facilities.
It should be noted that costs for water system equipment such as elevated water storage tanks and
wells can fluctuate over time to a greater degree than the overall construction cost index.
Therefore, engineering judgment should be employed when adjusting and refining these costs, as
the related improvements become part of the City’s active short-range capital improvement plan.
6.1.1Trunk Water Main Oversize Costs
Right-of-way costs that may be related to the final construction are not included. Trunk facilities
are defined as all pipes greater than 8 inches in diameter. The City’s cost, oversize cost, is only a
part of the total cost and is defined by the difference in cost between the actual improvement and
a residential equivalent improvement (defined as an 8-inch water main of equal length).
6.1.2Wells
Estimates for well construction include a test well, production well construction, pump and
motor installation, pitless unit installation, on site water main, hydrant, paving, meter vault,
electrical and controls. The value also includes an estimate for engineering and
administrative costs.
6.1.3Elevated Water Storage Tank
The cost presented is representative of current costs for an elevated steel or composite single
pedestal tank with 1.5 million gallons in storage capacity. A tank height of 160 feet is
assumed, based on a ground elevation of 1070 ft. and an overflow elevation of 1230 ft. The
estimate includes associated site work. The value also includes an estimate for engineering
and administrative costs.
6.1.4Raw Water Transmission Lines
Right-of-way costs that may be related to the final construction are not included. The
transmission line costs also do not include well site main installation as those costs are
addressed in the individual well cost estimates. The value includes an estimate for
engineering and administrative costs.
6.1.5Water Treatment Facility Improvements
Planning and cost estimates for future water treatment facility improvements are not
included in this report as they are being addressed in a concurrent facility plan
completed by Black and Veatch.
6.2 Capital Improvement Plan Timeline
Table 18 summarizes estimated annual costs (in 2013 dollars) for the recommended
future improvements.
Table 18–Capital Improvement Plan Timeline
1.5 MG
Raw Water
Trunk Main
Year Transmission Elevated Well Total
Extension
Main Storage Tank
2014 $189,000 $1,400,000 $1,589,000
2015 $189,000 $1,400,000 $1,589,000
2016 $189,000 $3,000,000 $3,189,000
2017 $189,000 $1,400,000 $1,589,000
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 38
Table 18Capital Improvement Plan Timeline
–
1.5 MG
Raw Water
Trunk Main
Year Transmission Elevated Well Total
Extension
Main Storage Tank
2018 $189,000 $189,000
2019 $189,000 $1,136,850 $700,000 $2,025,850
2020 $189,000 $189,000
2021 $189,000 $700,000 $889,000
2022 $189,000 $189,000
2023 $189,000 $700,000 $889,000
2024 $189,000 $243,000 $432,000
2025 $189,000 $189,000
2026 $189,000 $700,000 $889,000
2027 $189,000 $189,000
2028 $189,000 $189,000
2029 $189,000 $216,000 $405,000
2030 $189,000 $189,000
6.3 Trigger Chart
The timing of future water improvements will be influenced by a number of parameters.
Items such as development pressure in specific areas, aging facilities and/or facilities which
are undersized, availability of funds, etc. all play a role in the timing of future improvements.
Because of the factors involved, it is difficult to accurately predict the timing of future
improvements, especially those which may occur far into the future.
A trigger chart is presented in Figure 19, which correlates well and storage improvements to
system demands. Future capital improvement planning can thus be tied to actual system
demands and the timeline adjusted as necessary.
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 39
Figure 19 – Water System Capital Improvement Trigger Chart
40.000
35.000
30.000
25.000
ProjectedAverageDayDemandMetropolitanCouncilPopulation(MGD)
20.000
ProjectedAverageDayDemand2%Growth(MGD)
ProjectedMaximumDayDemandMetropolitanCouncilPopulation(MGD)
1.5MG
ProjectedMaximumDayDemand2%Growth(MGD)
Elevated
15.000
FirmCapacity(MGD)
Storage
TotalCapacity(MGD)
Tank
10.000
5.000
0.000
2013201520172019202120232025202720292031203320352037
Year
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 40
Appendix A
Raw Water System Analysis
Comprehensive Water Plan Update LAKEV 123875
City of Lakeville, Minnesota Page 41
MEMORANDUM
TO:Zach Johnson, Chris Petree, Ken Seuer
FROM:John Chlebeck
DATE:August 5, 2013
RE:Raw Water System Analysis
SEH No. LAKEV 12387514.00
The raw water supply system, including wells and transmission main, for Wells 4, 2, 19, 14, 12, 10, and
18 was analyzed for capacity to add additional wells to the line. This included a review of existing
aquifer data and pumping test data to make an estimate of well interference and well spacing requirements
for future wells to be constructed in the Jordan Aquifer. In addition, a computer hydraulic model of the
supply and transmission system was constructed to look at potential limitations on the existing
transmission line in its ability to convey additional flow from future wells.
Hydrogeologic Data Review
Existing data was reviewed to assess aquifer capacity and potential interference from future Wells 20, 21,
and 22 at locations along the transmission line between Well 19 and Well 14. This includeda review of
the Dakota County Geologic Atlas, along with pump testing information from Wells 12, 14, and 19. The
pump test data allowed for an estimate of aquifer transmissivity. The data was also used to develop
functions for drawdown vs. time pumped and drawdown vs. distance from the pumped well.
Figure 1shows drawdown estimates as a function of distance from a typical well in that part of the Jordan
aquifer. The curve represents drawdown at 1000 hours of continuous pump time at 1200 gpm, and is
based on the pump test data from Well 19. This shows some level of influence between the wells. To
relate this to Lakeville's wells, the proposed Well 21 location is about 1800 ft from Well 14. Therefore,
the new well is estimated to draw down Well 14 by approximately 7-8 feet when pumping at 1200 gpm
for 1000 hours.
This will have some impact on the capacityof Well 14, and should be looked at in more detailbeforethe
new well is drilled at that location. The pump setting for Well 14 appears to be at 300 ft. below ground
surface (according to the well log). The current pumping water level in the well is in the range of 180 -
210 ft below ground surface. Therefore, there doesn't appear to be a risk of drawing down the aquifer to a
point that is critical to pump operation. However, the extra drawdown will reduce suction pressure on the
pump and thus cause the pump tooperate at lower capacity.
It has been report by City staff that the wells do experience greater drawdown during summer months
when relatively high volumes are pumped from the Jordan aquifer. This agrees with the findings of this
analysis, and drawdown at existing wells can be expected to be increased with the addition of new Jordan
wells. This should be accounted for during design of new wells, and the impact on existing wells should
also be examined more closely before constructing new Jordan wells.
Short Elliott Hendrickson Inc., 3535 Vadnais Center Drive, St. Paul, MN 55110-5196
SEH is an equal opportunity employer | www.sehinc.com | 651.490.2000 | 800.325.2055 | 888.908.8166 fax
Raw Water System Analysis
August 5, 2013
Page 2
Figure 1 -Estimated Drawdown with Distance from Pumping Well
It should be noted that this analysis is based on pumping tests using the pumping well as the observation
well. It is recommended to have at least one non-pumping observation well for a pumping test that is
used to estimate aquifer properties. The transmissivity calculated from the pumping test data falls in the
middle of the range of expected values for the area, based on the Dakota County Geologic Atlas.
Therefore, the results are considered a reasonable estimate for planning purposes.
Transmission System Hydraulic Analysis
The hydraulic analysis of the raw water line that runs along Dodd Blvd. was the second part of this
analysis. Amodel of the raw water system was constructed to look at the effects on transmission main
headloss, velocity, and hydraulic grade from adding additional wells to this line. The results are shown in
Figure 2.
Raw Water System Analysis
August 5, 2013
Page 3
Figure 2 -Hydraulic Grade Impact from New Wells
The figure showsthe impact to hydraulic grade (pressure) along the line with the addition of future wells.
The current hydraulic grade was calculated assuming Wells 4, 2, 19, 14, 12, 10, and 18 are pumping into
the line at their design capacities, and that the line discharges to the water treatment plant at
approximately ground elevation (1089 ft MSL). This is probably a conservative analysis as all of those
wells are not likely to operate at their design capacitiessimultaneously.
The hydraulic analysis shows that there is likely to be an impact to the hydraulic grade in that
transmission line from the added pumping of Wells 20, 21, and 22. Each of these new wells was assumed
to have a design capacity of 1200 gpm. With the addition of each well to the model, the hydraulic grade
upstream of the proposed well locations is increased by 5-10 feet. This will result in an additional 5-10
feet of back-pressure on the wells, which will also tend to decrease the production capacity of the wells.
The impact is expected to be greatest to Wells 4, 2, and 19. Wells that are closer to the water treatment
plant will have less impact.
Figure 3shows the impact to hydraulicgrade if all wells are operatingat 1000 gpm (except Well 18 at
600 gpm). This may be closer to the actual hydraulic impact from simultaneous pumping of the wells
since it is reported that the wells operate at lower rates during the summer when they are pumped
simultaneously. This is a result of both aquifer drawdown and system backpressure on the well pumps.
Raw Water System Analysis
August 5, 2013
Page 4
Figure 3 -Hydraulic Grade Impact with Reduced Pumping Rates at Wells
The reason for the increased hydraulic grade in the transmission main is the increased head loss caused by
increased flow in the line. Figures 4, 5, and 6 (attached) indicate velocities in the transmission main
under varying pumping conditions. Generally, velocities up to 10 feet per second are acceptable in a
transmission main. However, increased velocity will result in additional frictional head losses that will
increase back pressure on the existing well pumps and cause a reduction is production capacity.
PreliminaryWellhead Protection Areas for Wells 20, 21, and 22
It is recommended during the site selection for a new well to evaluate potential contaminant sources
around the well site and other potential risks associated with well use. Figure 7 shows preliminary
wellhead protection areas around the proposed locations for Wells 20, 21, and 22. Based on the confined
nature of the aquifer, estimated well pumping rates, and estimated aquifer porosity, the preliminary
wellhead protection area boundary is calculated to be a circle with a diameter of approximately 4500 ft.,
following recommended methods from the Minnesota Department of Health.
There is one petroleum storage tank from the MPCA database that is within the preliminary wellhead
protection area for future Well 22. This site is identified as Cherryview Elementary School. There are
also some commercial small quantity hazardous waste generators along Dodd Blvd. within the
preliminary wellhead protection area for Well 20. These include a CVS pharmacy, a medical clinic, and a
Raw Water System Analysis
August 5, 2013
Page 5
dental office. None of these are thought to be immediate threats to future wells in the locations shown,
especially given the protected nature of the Jordan aquifer.
There are 3 private wells located in close proximity to the future locations identified for Wells 21 and 22.
These wells are all identifiedas St. Peter sandstone wells, and their well logs are attached to this
document for reference. The St. Peter is known to have hydraulic connection with the Jordan aquiferin
parts of Dakota County, though most commonly they are hydraulically separated by a shale layer at the
base of the St. Peter formation. There is a possibility for some influence on the private wells from
municipal pumping in the Jordan, however. The City should be prepared for that possibility. Better
confirmation could be obtained during recommended test pumping prior to the construction of a new well
in the area.
Conclusions
The analysis conducted for this study shows that future wells along the Dodd Blvd. raw water
transmission main will create some level of impact to the existing wells. This impact includes drawdown
from interference in nearby wells, and increased back-pressure from head loss in the transmission main.
The degree of impact will be dependent on the simultaneous pumping rates in the existing and future
wells.
Itis possible that all of the wells, including future Wells 20, 21, and 22, could be operated around 1000
gpm with the existing pumps and motors. The specific pump curves shouldbe reviewed to get a more
accurate estimate of how the pumps will respond to the increased discharge pressure and reduced suction
pressure.This should be done during preliminary design of any future well to ensure that impacts to
existing facilitiesare not prohibitive to achieving the planned capacity of the new well.
The proposed location for Well 21 (as currently shown in the plans for water main construction along
Dodd Blvd. planned for this year) is thought to be a viable location for a new municipal well. The
alternate location discussed at our meeting on March 1 (in the SE quadrant of the Highview Ave. and
Dodd Blvd. intersection)is also viable for development of a well. In fact, itis possible that wells could
be constructed at both locations. The two sites are approximately 1000 feet apart, and there would be an
interference effect between the two wells, but there is a strong likelihood that two municipal wells could
be supported in the Jordan Aquifer at that location. For that reason, some consideration should be given
to stubbing the raw water transmission main across Dodd Blvd. to the alternate well location during the
planned reconstruction activities this year.
There are apparent impacts to the existing wells with the addition of each new wellalong the transmission
main. These impacts need to be evaluated in more detail prior to the construction of any new well. This
evaluation should include aquifer test pumping at each location being considered, to evaluate interference
with existing wells as well as local aquifer properties. In addition, a detailed review of existing well
pump performance characteristics should be completed to provide a better estimate of the impacts that can
be expected with greater pumping from the aquifer.
jdc
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c:Miles Jensen, SEH
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MINNESOTA DEPARTMENT OF HEALTH
1999/01/28
Unique No.
00251988Update Date
WELL AND BORING RECORD
County NameDakotaEntry Date1999/01/28
Minnesota Statutes Chapter 1031
Well Depth Depth Completed Date Well Completed
Township Name Township Range Dir Section Subsection
ft.ft.300
300
11420 8DDADCAW
Non-specified Rotary
Well NameDrilling Method
H130271
H130271Well Hydrofractured?
Drilling Fluid
Contact's Name
YesNo
Fromft.
ft. to
APPLE VALLEY MN
Domestic
Use
Hole Diameter
YesN
Casing
Drive Shoe?
Casing Diameter Weight(lbs/ft)
GEOLOGICAL MATERIAL COLOR HARDNESS FROM TO
5249in. toft
GLACIAL DRIFG
0120
PLATTEVILLE FLOATER ?
120150
ST. PETER SANDSTONE
150248
ST. PETER SANDSTONE
248340
ft.
Fromft. to340
Screen
N249
Open Hole
MakeType
Land surface1999/01/28
Date
Static Water Levelft. from
130
PUMPING LEVEL (below land surface)
hrs. pumpingg.p.m.
ft. after
Well Head Completion
Pitless adapter mfr
Model
Casing Protection
12 in. above grade
At-grade(Environmental Wells and Borings ONLY)
No
Well grouted? Yes
Grouting Information
Nearest Known Source of Contamination
type
ft.direction
Well disinfected upon completion?YesNo
Not Installed
Pump
Date Installed
Mfr name
ModelVolts
HP
g.p.m
Drop Pipe LengthCapacity
ft.
REMARKS, ELEVATION, SOURCE OF DATA, etc.
Type
WELL SEALING NO. H-130271.
Any not in use and not sealed well(s) on property?No
Yes
GAMMA LOGGED 1-28-1999.
YesNo
Was a variance granted from the MDH for this Well?
1063
USGS Quad:Farmington
Elevation:
Lic. Or Reg. No.MGS
Well CONTRACTOR CERTIFICATION
Aquifer:OSTP
Alt Id:
License Business Name
Report Copy
Name of Driller
HE-01205-06 (Rev. 9/96)
MINNESOTA DEPARTMENT OF HEALTH
1991/08/14
Unique No.
00124316Update Date
WELL AND BORING RECORD
County NameDakotaEntry Date1990/03/30
Minnesota Statutes Chapter 1031
Well Depth Depth Completed Date Well Completed
Township Name Township Range Dir Section Subsection
ft.ft.2551976/09/18
255
11420 8DDDADAW
Well NameDrilling Method
DAVID ERSTAD
Well Hydrofractured?
Drilling Fluid
YesNo
Fromft.
ft. to
Domestic
Use
Hole Diameter
YesN
CasingDrive Shoe?
Casing Diameter Weight(lbs/ft)
GEOLOGICAL MATERIAL COLOR HARDNESS FROM TO
4224in. toft
SOIL BLACK
03
CLAY RED
SOFT 37
CLAY YELLO
SOFT 734
CLAY BLUE
SOFT 34100
ft.
Fromft. to255
Screen
N224
Open Hole
CLAY + GRAVEL BROW
HARD 100126
MakeType
CLAY YELLO
SOFT 126134
GRAVEL BROW
HARD 134153
SANDSTONE YELLO
SOFT 153187
SANDSTONE GRAY
SOFT 187224
Land surface1976/09/18
Date
Static Water Levelft. from
129
SANDSTONE WHITE
HARD 224255
PUMPING LEVEL (below land surface)
hrs. pumpingg.p.m.
ft. after
12915
Well Head Completion
Pitless adapter mfr
Model
Casing Protection
12 in. above grade
At-grade(Environmental Wells and Borings ONLY)
No
Well grouted? Yes
Grouting Information
Nearest Known Source of Contamination
type
ft.direction
85SDF
Well disinfected upon completion?YesNo
Not Installed
Pump
Date Installed
Y
Mfr name
FAIRBANKS MORSE
ModelVolts230
7511 HP0.75
g.p.m
Drop Pipe LengthCapacity
ft.10
165
REMARKS, ELEVATION, SOURCE OF DATA, etc.
Type
S
18026 DODD BLVD. W.
Any not in use and not sealed well(s) on property?No
Yes
YesNo
Was a variance granted from the MDH for this Well?
1053
USGS Quad:Farmington
Elevation:
Lic. Or Reg. No.19163
Well CONTRACTOR CERTIFICATION
Aquifer:OSTP
Alt Id:
License Business Name
Report Copy
Name of Driller
HE-01205-06 (Rev. 9/96)
MINNESOTA DEPARTMENT OF HEALTH
1991/08/14
Unique No.
00124319Update Date
WELL AND BORING RECORD
County NameDakotaEntry Date1990/03/30
Minnesota Statutes Chapter 1031
Well Depth Depth Completed Date Well Completed
Township Name Township Range Dir Section Subsection
ft.ft.2551976/10/20
255
11420 8DDDDACW
Well NameDrilling Method
ROBERT PUGH
Well Hydrofractured?
Drilling Fluid
YesNo
Fromft.
ft. to
Domestic
Use
Hole Diameter
YesN
CasingDrive Shoe?
Casing Diameter Weight(lbs/ft)
GEOLOGICAL MATERIAL COLOR HARDNESS FROM TO
4228in. toft
CLAY YELLO
SOFT 019
CLAY BLUE
SOFT 19113
GRAVEL BROW
HARD 113127
CLAY YELLO
SOFT 127139
ft.
Fromft. to255
Screen
N228
Open Hole
GRAVEL BROW
HARD 139141
MakeType
SAND BROW
SOFT 141173
LIMESTONE YELLO
SOFT 173174
GRAVEL FINE BROW
SOFT 174194
SANDSTONE YELLO
SOFT 194208
Land surface1976/10/20
Date
Static Water Levelft. from
129
SANDSTONE GRAY
SOFT 208216
PUMPING LEVEL (below land surface)
hrs. pumpingg.p.m.
ft. after
12915
SANDSTONE WHITE
SOFT 216228
Well Head Completion
SANDSTONE WHITE
HARD 228255
Pitless adapter mfr
Model
Casing Protection
12 in. above grade
At-grade(Environmental Wells and Borings ONLY)
No
Well grouted? Yes
Grouting Information
Nearest Known Source of Contamination
type
ft.direction
87SDF
S
Well disinfected upon completion?YesNo
Not Installed
Pump
Date Installed
Y
Mfr name
FAIRBANKS MORSE
ModelVolts230
10014 HP1
g.p.m
Drop Pipe LengthCapacity
ft.11
155
REMARKS, ELEVATION, SOURCE OF DATA, etc.
Type
S
17965 HIGHVIEW AVE.
Any not in use and not sealed well(s) on property?No
Yes
YesNo
Was a variance granted from the MDH for this Well?
1044
USGS Quad:Farmington
Elevation:
Lic. Or Reg. No.19163
Well CONTRACTOR CERTIFICATION
Aquifer:OSTP
Alt Id:
License Business Name
Report Copy
Name of Driller
HE-01205-06 (Rev. 9/96)