HomeMy WebLinkAboutCity Council Packet 07-27-2004 SpecialAgenda
City of Plymouth
Special City Council Meeting
Tuesday, July 27, 2004
5:30 p.m.
Public Safety Training Room
3400 Plymouth Blvd.
1. Call to Order
2. Discuss Water Conservation Options
3. Set Future Study Session
4. Adj ourn
Agenda Number:
DATE: July 20, 2004 for the City Council Meeting of July 27, 2004
TO: Laurie Ahrens, City Manager
FROM: IDaniel L. Faulkner, P.E. Director of Public Works
SUBJECT: OPTIONS FOR WATER CONSERVATION
ACTION REQUESTED: Consider water conservation options and provide direction to staff on
preferred option(s).
BACKGROUND: One element of the City's Comprehensive Plan is the Water Supply and
Distribution Plan. One of the purposes of this plan as required by the Metropolitan Council is to
prepare and/or update the City's Water Conservation Plan in order to reduce overall demand for water
and encourage wise use of a limited resource. This goal of conserving water is also strongly supported
and at times required by the Department of Natural Resources (DNR). All municipal water suppliers
must annually submit Water Usage Reports to the DNR to compare the amount of water pumped from
the supplying aquifer, or surface water source, to the quantity "permitted" by the DNR for the
municipality. A DNR Appropriations Permit is required for all municipal wells. In 2003, Plymouth
exceeded our permitted amount (3.6 billion gallons) of pumped ground water by 210 million gallons
5.8%). While this is less than the 10% benchmark whereby DNR requires a permit amendment, they
are looking closely at our Conservation Plan and what more we can do. This is particularly important
when we need to request an additional Appropriations Permit for any new wells such as No. 14 and
No. 15.
The City's official Water Conservation Plan is included as Appendix 9E of the City's Comprehensive
Plan. The plan consists of Pages 9-E-1 through 9-E-11 and are attached for your information. This
plan was adopted as part of the overall Comprehensive Plan that was approved on August 8, 2000. As
stated in the plan, the conservation goal is to reduce both the average and maximum day demands by
14%:
Reduce average day residential per capita water use from 111 gpcd (gallons per
capita per day) to no more than 95 gpcd.
Reduce maximum day to average day ratio from 2.9 to 2.5.
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SUBJECT: OPTIONS FOR WATER CONSERVATION
Page 2
The plan includes a discussion of current conservation measures, an Implementation Plan for further
conservation measures, and criteria for evaluating effectiveness of the Conservation Program. The
measures discussed are as follows:
1. Metering: It is important that meters work properly and the City checks and
replaces meters as necessary.
2. Water Audits, Leak Detection and Repair: Unaccounted for water is the difference
between the volume of water sold and the volume of water withdrawn from the
source. Unaccounted for water use in 2000 was about 11 %. Updated figures
indicate that in 2002 the unaccounted for/un-metered volumes were approximately
10% of the water withdrawn from the aquifer and in 2003 it was approximately
11%. The majority of the unaccounted for water is due to watermain breaks,
hydrant flushing, leaks in the system, construction activities, etc. As our system
ages, we need to continue to maintain our system and promptly repair leaks. This is
one area that the Met Council and Department of Natural Resources (DNR)
encourage communities to address, particularly when the unaccounted for volumes
reach 10% or more. In addition, this lost water equates to a loss of revenue for the
City. The City Supervisor of Water and Sewer, Brian Young, calculated that in
2002 there were 304 million gallons unaccounted for which would equate to
212,800 lost in 2002. Similarly in 2003, there were 412 million gallons
unaccounted for which equates to a loss of approximately $280,000. While the City
could not hope to account for all of this lost revenue due to such City activities as
hydrant flushing and water treatment plant operations, there is the potential for some
significant cost savings through a program of leak detection and repair.
3. Conservation — Oriented Water Rates: The City's tiered water rate system went into
effect on May 1, 2000, as follows:
While the tiered rate system is typically an effective way to conserve water, our
records do not indicate a decline due to this rate structure, although weather and
temperature are significant variables in this consideration.
4. Regulation: State and Federal plumbing codes require more efficient water fixtures.
In addition, a new State law (MN Statute 103G.298) passed in 2003 requires all new
landscape irrigation systems to contain an automatic shutoff during periods of
sufficient moisture. As indicated in Roger Knutson's attached letter though,
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SUBJECT: OPTIONS FOR WATER CONSERVATION
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enforcement of this law only pertains to large irrigation systems pumping a
minimum of 1,000 gallons per day or 1,000,000 gallons per year.
5. Education and Information Programs: The City's odd/even water restrictions on
outdoor water use was implemented several years ago and while this program
doesn't necessarily conserve water, it does even out the peak demands which relate
to the capacity we must provide. In addition, we have used this program as an
educational tool to inform our residents on the wise use of water and the need to
conserve water.
6. Retrofitting Programs: The retrofitting of existing water fixtures is largely up to
individual property owners as a City sponsored program would not have sufficient
payback. The City will continue to promote these programs as a way to conserve
water and save the residents money.
7. Pressure Reduction: While we typically hear of low water pressure areas in the
City, there are also areas of high pressure which can tend to promote high water
usage. Promotion of individual pressure reducing valves is another way the City
can work toward conserving water.
8. Large Water Users: While the City's Water Conservation Plan does not indicate
any specific means of reducing commercial/industrial and institutional customers'
water usage, promotion of conservation programs will continue. One example of
this occurring is through the Plymouth Business Environmental Partnership where,
with staff assistance, a Plymouth industry significantly reduced their water usage.
Also attached is a copy of a Metropolitan Council Report dated May 2004 entitled Water Demand and
Planning in the Twin Cities Metropolitan Area (an update to the long term Water Supply Plan). While
this report addresses the trends throughout the metropolitan area, there is specific information
contained in the appendices for 83% of the 98 separate municipal water suppliers in the metropolitan
area. The report indicates no apparent correlation between residential per capita water use and average
lot size, average household income, or price of water. As one would expect, there is a correlation
between residential per capita water use and precipitation and temperature. While the report does
stress a need for water conservation efforts, it also indicates that additional studies are necessary to
determine the full limitations of the region's water supply system. The report also indicates that a
future study should be undertaken to determine the effectiveness of water conservation measures to
reduce demand in the twin cities area.
DISCUSSION OF OPTIONS: As indicated above, the City went to a tiered water rate billing
structure in May 2000. Our Finance Department referenced studies that predict a reduction in water
use of approximately 1% to 2% with the rates Plymouth set due to the higher cost when larger amounts
of water are used. It would be very difficult to determine if the tiered rate structure did indeed reduce
demand due to the other variables that affect the demand, including weather variations over time,
particularly the timing and frequency of rainfall. along with temperatures. It does appear intuitive
though that increasing rates a significant amount through the tiered rate structure could have a definite
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SUBJECT: OPTIONS FOR WATER CONSERVATION
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impact on water usage. Currently, Plymouth's water rates are among the lowest rates in the
metropolitan area.
Another potential option for conserving water would be a time of day ban. This is a technique that the
Department of Natural Resources indicates has been used successfully in other cities as a way to
conserve water. The DNR has suggested that Plymouth consider a time of day ban from 10:00 a.m. to
6:00 p.m. seven days a week, although this is not a mandate. An example of what some other
metropolitan cities have approved for mid-day bans is as follows: City of Savage Noon to 5:00 p.m.,
City of Prior Lake 11:00 a.m. to 5:00 p.m., City of Minnetonka 11:00 a.m. to 5:00 p.m., and Eden
Prairie 12:00 p.m. to 5:00 p.m. In general, these bans extend from May through September. In the
case of Eden Prairie's restrictions, they do include opportunities for exceptions for commercial or
business enterprises whose economic well being is dependent upon irrigation of a lawn, grass, or turf
owned, leased, or operated by the business; employees and agents of the City where watering or
irrigation of grass or turf is necessary for playfields to not suffer unreasonable damage; owners and
lessees of lands newly sodded or grass seeded which requires irrigation to prevent loss of new sod,
seed or immature turf or grass for a period of 30 days. Our Parks Department is particularly interested
in the exception relating to the City playfnelds.
The other options mentioned in the City's current Water Conservation Plan should continue to be used.
This includes educational efforts through the City's website, cable TV channel, billing stuffers, etc.
Another option that could be considered in the future would be a peak use water rate. In order to
utilize this type of rate system, the City's water meters would all need to be replaced with meters that
could be read remotely at any time of the day.
RECOMMENDATIONS AND CONCLUSIONS: The City Council should consider all feasible
means of water conservation options presented. A combination of conservation measures could
sufficiently reduce future maximum day demand to lessen the need of future facility expansions. This
in turn could result in both a monetary savings and help address future aquifer supply concerns. At a
minimum, staff would recommend that the City Council direct staff to prepare an ordinance instituting
a time of day ban with an effective date in 2005.
Daniel L. Faulkner, P.E.
Director of Public Works
attachments: MN Statute 103G298
Memorandum from Roger Knutson 7/9/04
Water Conservation Plan
Metropolitan Council Report
Resolution
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Minnesota Statutes 2003, 103G.298
Minnesota_ Statutes 2003, Table of Chapters
Table_ Ofcontents_ for Chapter 10'G
103G.298 Landscape irrigation systems.
All automatically operated landscape irrigation systems
shall have furnished and installed technology that inhibits or
interrupts operation of the landscape irrigation system during
periods of sufficient moisture. The technology must be
adjustable either by the end user or the professional
practitioner of landscape irrigation services.
HIST: 2003 c 44 s 1
Copyright 2003 by the Office of Revisor of Statutes, State of Minnesota.
Page 1 of 1
http://www.revisor.leg.state.nm.us/stats/103G/298.html 7/13/2004
MEMORANDUM
FROM: BJF
DATE: 7/9/2004
RE: Plymouth/landscape irrigation systems
Issue: Whether the city is obligated and/or authorized to enforce Minn.Stat. § 103G.298?
Answer: No. If the user of a landscape irrigation system does not meet the minimum DNR
permit usage threshold, then there is no explicit statutory obligation or authorization for City's to
enforce that section.
Minnesota Statutes § 103G.298 was added in 2003. The Department of Natural Resources has
primary rule making and enforcement authority for all of Chapter 103G but has not yet
promulgated any rules on § 103G.298. The only provision relating § 103G.298 to municipalities
is § 103G.105, subd.2, which provides that "municipal governments must cooperate with the
commissioner in monitoring and enforcing water permits." Under current DNR rules, a permit is
required for any non-agricultural irrigation system that pumps more than 10,000 gallons per day
or more than 1,000,000 gallons per year. Minn. R. Ch. 6115.0620. For irrigation systems using
less than this amount, no permit is required. Thus, § 103G.105 clearly does not require that
cities do anything with respect to landscape irrigation systems pumping less than 10,000 gallons
per day or less than 1,000,000 gallons per year.
Under the Plymouth City Code (§§ 400, 720) and the State Plumbing Code (Minn. R. Ch. 4715),
the City must issue a permit to connect to the City water supply and must inspect such
connection. Yet, both the permit and inspection are only to ensure compliance with the State
Plumbing Code. Because the Plumbing Code requires neither compliance with § 103G.298 nor
general compliance with Chapter 103G, the City is not responsible for or enforcing those
provisions and is not directly authorized to do so. Furthermore, Chapter 103G only address
penalties for violating the terms of a permit and other specific violations. Where no permit is
required, as is the case for a landscape irrigation system using less than the proscribed amounts,
there are no explicit enforcement or penalty provisions for either the DNR or a city.
In practice, the DNR "encourages" cities to enforce the provision but they do not actively
enforce the provision unless the user meets the minimum permitting threshold. If the City
wishes to obtain compliance, the inspector could state that unless the irrigation system is
equipped in compliance with the law, it will be reported to the DNR.
A
PLYMOUTH. MINNESOTA
COMPREHENSIVE PLAN
Adopted
August 8, 2000
City of Plymouth, Minnesota
3400 Plymouth Boulevard
Plymouth, Minnesota 55447-1482
Telephone (763) 509-5000
www.ci.plymouth.mn.us
Appendix 9-E
Water Conservation Plan
Appendix 9 -E - Water Conservation Plan
Role of Conservation
The water conservation plan for the City of Plymouth is intended to reduce the demand for water, improve the efficiency of water use, and reduce loss and waste of water. Conservation can be analternativetodevelopingadditionalsourcesofwatertomeetpeakdemandsfornon-essential usesofwater. Reducing the peak use of water will delay or reduce additional source development andwaterstoragerequirements.
The City's conservation goal is to reduce both the average and maximum day demands. For theWaterSupplyandDistributionPlan, the City has adopted the following conservation goals:
Reduce the average day residential per capita water use demand 14 percent, from 111 gpcdgallonspercapitaperday) to no more than 95 gpcd, even on peak years.
Reduce the maximum day to average day ratio from 2.9 to 2.5, or a 14 percent reduction. FromtheTableatthebackofthisAppendix, it shows the maximum day to average day ratio has beenover2.9 two out of the last ten years.
Demand reduction programs will target uses associated with peak demands, such as outdoor waterpractices. By reducing the amount of water used for watering lawns and plants, filling swimmingpoolsandwashingcars, Plymouth intends to reduce peak demand and maintain the reduced demandoverthenextplanningperiod. Specific program initiatives will be provided in more detail under theheadingWaterConservationPrograms.
Future revisions of this report should adjust projected water demands based on the results of theCity's conservation plan.
Water Conservation Potential
The City of Plymouth is a growing community with an increasing population base. The overalldemandonthewatersystemhasincreasedsteadilyoverthepasttenyears. In communities withgrowingpopulationsandplannedsystemexpansions, water conservation can play an important roleinthemanagementofwaterresources. Adopting water efFicient practices as a part of the City's BestManagementPracticesmaydelaythedevelopmentofadditionalwells.
Since Plymouth's water system is growing and the peak demand periods are increasing, the focusofthewaterconservationplaninthefuturewillbeoncontinuingthewiseuseofwater, maintainingthepresentconditionofthewatersystem, and making repairs to the original distribution and supplyareasasrequired. The following is a discussion of water conservation potential for each of the areas
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan
9 -E -I
addressed in the Water Supply Plan as well as conservation potential for the various customer
classes.
Per Capita Water Use
Per capita water use information is beneficial because it shows who is using the water and how much
water they are using on average. Plymouth's residential per capita water use has ranged from 74 to
119 gallons per capita per day (gpcd) and total per capita water use has ranged from 126 to 174 gpcd.
The total per capita water use on the maximum day has ranged from 231 gpcd to 436 gpcd. The
water usage in any year is highly dependent on climatic and other conditions. The design of
Plymouth's water system must be based on peak usage years. Water use would be expected to be
at least 174 gpcd in another dry year. However, Plymouth has selected 160 gpcd total average per
capita and 400 gpcd maximum day per capita as the starting point for its conservation program. This
represents an 8 percent reduction in both average and maximum day per capita water use.
Water Demand by Customer Category
Clearly it is appropriate to create conservation programs that target customer categories. The
following discussion outlines the conservation potential for each customer category.
Residential Customers: The residential sector consumes 64 percent of the total water pumped each
year. The greatest potential for water savings for residential customers is utilizing water efficient
habits and implementing water efficient outdoor water practices. Utilizing water efficient practices
would reduce the total water pumped annually as well as decrease some of the peak demand periods.
Institutional: The institutional sector uses only about 3 percent of the total water pumped each year.
Schools are good candidates for water conservation programs because they have a captive audience
i.e. the students) and benefit from the cost savings derived by using less water. However, it is not
realistic to hope that conservation programs targeted at the institutional sector will save a significant
amount of water. The best goal of institutional conservation programs is to educate people and serve
as a model conservation program to the rest of the community.
CommerciaUlndustrial. The commercial sector/industrial uses 22 percent of the total water
pumped. During the last ten years, the demand for water has increased as connections have
increased. Private business usually benefits from conservation programs if there is sufficient
payback potential. It is difficult to target conservation programs toward commercial users because
their uses are usually industry specific. For instance, a car wash is going to use large amounts of
water. If the payback is sufficient for the owner to invest in technology for recycling water, the
owner will usually undertake the improvement. For businesses, the payback needs to be there in
order to justify the upgrade. However, the City could target education initiatives to business owners
and provide them with resources to seek out about water conservation potential.
Unaccounted for water: The unaccounted for water use has remained near the American Water
Works recommendations of 10 percent. The City's "other" water use was 11 percent. Other water
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-2
use includes hydrant flushing, flooding rinks, and other minor uses, in addition to unaccounted for
water. The City should always strive to reduce the amount of water that is unaccounted for - both
from an environmental and a revenue perspective.
Seasonal and Peak Water Demands
Water conservation in Plymouth will have its greatest impact on seasonal and peak water demands.
As shown in the table in the back of this Appendix, there have been two years in the past ten years
where the maximum day demand has been almost three times the average day usage. Although the
maximum day event does not occur often, the peak demands place an enormous amount of stress on
the system and govern the design of the water system. Targeting the maximum day demands will
have the greatest impact on the size and amount of facilities the City needs to construct. Through
an appropriately target water conservation program, Plymouth intends to reduce the demands placed
on the water system during peak periods.
Water Conservation Programs
Formal water conservation planning is a relatively new concept for many water utilities, and the City
of Plymouth is no exception. The City of Plymouth has adopted policies that encourage conservation
such as metering of customers and sprinkling regulations.
The challenge for conservation program development is targeting uses that can be reduced through
physical change (toilet retrofits) and habitual change (using a broom, not water to clean sidewalks
and driveways). These changes can be encouraged through a number of different water conservation
programs such as education initiatives, retrofit programs and rebates.
The key for effective water conservation programs in Plymouth is planning. As Plymouth's
population grows, so will the demand for drinking water and wastewater treatment services.
Through appropriate water conservation measures, capital expenditures for increased demands can
be delayed or reduced, which is a large financial saving for the community.
The following is a discussion of current conservation measures, an implementation plan for further
conservation measures, and criteria for evaluating the effectiveness of the conservation program.
1. Metering: All current and future water users are and will be metered. The City currently
checks meters on the system and replaces all residential meters over fifteen years old. All
large meters are being tested, repaired or replaced based on AWWA (American Water
Works Association) recommendations.
The billing system automatically identifies users that have experienced a large change in
usage. This information initiates a meter check from the utility staff.
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-3
Implementation Plan: In 2000, the Director of Public Works and Utility Supervisor will
establish a plan for calibration and repair schedule of the large meters at well pump houses
and water treatment plants.
Also in 2000, the Utility Supervisor will meet with the City Billing Department to see if they
can establish a method of tying multiple meters to a single account. The current billing
software cannot recognize multiple meters for a single account.
2. Water Audits, Leak Detection and Repair: Unaccounted-for water is the difference
between the volume of water sold and the volume of water withdrawn from the source.
Unaccounted for water use (listed as "Other") is about 11 percent. As the system ages, the
City will need to continue to maintain the system and promptly repair leaks. Pipes within
streets scheduled for reconstruction are tested for leaks. The majority of the unaccounted
for water is due to water main breaks, hydrant flushing, leaks in the system, construction
activities, etc.
Implementation Plan: The Utility Supervisor will continue to monitor these losses and
work to ensure that they are able to maintain their unaccounted for water loss at less than 10
percent. In 2000, the Utility Supervisor will provide recommendations for metering or
estimating water use for construction, rink flooding, hydrant flushing, and breaks. This will
lead to a more accurate and meaningful measurement of unaccounted for water. The plan
will be re-evaluated after the large water meters are calibrated.
The Utility Supervisor, Director of Public Works and Billing Department will meet in 2000`
to establish a strategy to provide water audits for large -volume users who experience a large
increase over the past billing period. The billing system automatically "tags" these accounts.
In 2001, the Utility Supervisor will contact NSP to see if they still offer the shower head
replacement program.
3. Conservation -Oriented Water Rates: The City has recently approved a tiered rate system
for its residential customers, and bills its customers bi-monthly. A tiered rate has been
shown to be an effective conservation measure. A base rate is charged which includes fixed
administrative costs, plus a set rate per 1000 gallons used. The following rates will become
effective on May 1, 2000.
Bi -Monthly Billing Rates:
Base Rate $3.88
Water Rate (under 12,500 gal.) $0.70 per 1000 gal.
Water Rate (12,501 to 35,000 gal.) $0.80 per 1000 gal.
Water Rate (over 35,000 gal.) $1.50 per 1000 gal.
Commercial and industrial accounts are billed on a monthly basis, at a rate of $0.80 per 1000
gallons. The City will continue to investigate alternative rate systems.
C
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-4
The rate system has been developed to pay for the true cost of supplying, treating and
delivering the water, including maintenance. Future capital expenditures will be financed
through connection charges, area charges, and assessments.
Implementation Plan: The City will evaluate the effectiveness of the new rate system.
4. Regulation: The City relies on the following regulations to provide short-term demand
reduction and long-term improvements in water use efficiencies.
A. State and Federal Plumbing Codes: All new homes and retrofits of existing homes will
have water efficient fixtures.
B. Short-term Reduction Procedures: Described in the Emergency Preparedness Plan.
Implementation Plan: The Utility Superintendent will evaluate the effectiveness of the
new water use restrictions and make recommendations for improvements.
5. Education and Information Programs: Plymouth has made and is committed to making
a strong effort to educate the public on the benefits of water conservation, in the following
manners:
The City is an active participant in the Plymouth Business Environmental Partnership
PBEP). The City has conducted educational workshops on water conservation for
Plymouth businesses, through its participation in PBEP. The City has also assisted in
forming focus groups among the business community to discuss the importance of
water conservation, through its participation in PBEP. In addition, the City has printed
articles on water conservation in the PBEP newsletter, The Advantage.
The City includes information on lawn sprinkling restrictions and wise use of water in
the packets that are provided to new residents. This information is also publicized in
the City newsletter during the Summer months, posted on the City's web site, and
provided on cable television. In addition, a water restriction hot line has been set up
to provide information about the City's lawn sprinkling restrictions.
The City has sponsored an Environmental Fair annually since 1995. The Fair is held
at one of the elementary schools in the City. Staff from the City's Recycling, Water
Resources and Forestry divisions, as well school staff, students and community
volunteers are involved with developing the program. The Fair includes up to thirty
exhibitors with many "hands-on" activities for the students and parents. The evening
event attracts about 1,000 attendees. The school also tailors their classroom science
program at that time to the environment and issues such as water conservation.
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-5
Implementation Plan: In 2001, the City will focus its efforts on education material that is
targeted toward user groups and user practices. The City will evaluate the cost of the
program as well. The City will consider the following education foci: `
Education targeted to the public on the benefits of water conservation, focusing on habits
and efficient uses of water (this could tie in with the home audit information i.e. how to
check for leaking fixtures, water efficient fixtures, etc.).
2. Education targeted toward developers, focusing on water efficient plantings for new
developments.
3. Education focused toward commercial users, providing them with resources to contact
for water efficient technologies.
6. Retrofitting Programs: The City Building Inspector will enforce the existing plumbing
codes relating to retrofitting existing water fixtures. As the gallons per capita per day are
low, the City will not pursue a mandated retrofit program for the residential sector. The
payback for a residential program would be too long to justify the cost. With the enactment
of the 1992 Federal Energy Policy Act, all fixtures available for replacement are water
savers. As homeowners gradually begin to replace aging fixtures or remodel their homes,
the high user fixtures will be replaced by water saving fixtures. The payback for a
residential customer will depend upon fixture use and home water habits. If the residential
gallons per capita dramatically increases and it appears that there may be a good savings
potential for a city wide retrofit program, the City will revisit the possibility of funding a
retrofit program at that time.
Implementation Plan: Retrofit programs makes sense for public buildings provided it is a
part of the maintenance program, or regular replacement schedule of parts. Gradually, all
higher use fixtures will be replaced with lower consumption fixtures, and because the change
out will occur as older parts need replacing, there should not be much of a financial impact
on the public buildings' budgets.
Water sensors for residential, commercial and industrial sprinkling systems will be
evaluated, regarding what the payback is etc.
7. Pressure Reduction: The City water system has been designed to ensure that static and
residual pressures in the water service area are maintained between 40 psi and 120 psi.
Users with pressures above 80 psi. will be required to install individual pressure reducing
valves at the point of service, unless special needs dictate. The only method available to the
City to reduce pressures in an emergency to reduce demands is to lower the water level in
the water towers. This procedure is unacceptable resulting in reductions of available fire
protection.
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-6
8. Large Water Users: Plymouth has some commercial, industrial, and institutional customers
that have fairly high water demands. Plymouth will continue to ensure that large water users
do their "fair share" of conserving water. All of the conservation programs described above
also apply to commercial, industrial, and institutional users.
Implementation Plan: In 200 and 2001, the Water Utility Supervisor and Public Works
Director will meet with each of the large water users to discuss ways each user could
conserve water. Representatives from Metropolitan Council Wastewater Services will also
attend the meetings to discuss potential savings conservation could bring to the wastewater
side. Further action will be decided after these meetings.
An ongoing part of the plan will be to ensure that the Utility Supervisor and Public Works
Director are involved in discussions with potential new commercial/industrial clients to:
evaluate the impact of the proposed business on the comprehensive water plan, and to see
what water conservation measures can be implemented in the planning for the new facility.
Plymouth Water Supply and Distribution Plan
Appendix E - Water Conservation Plan 9-E-7
Appendix
Plymouth Water Supply & Distribution Plan_
Pumping Records and Demand Variations
r7098803
Days
Month
31
Feb 28
Mar 31
Apr 30
May 30
Jun 30
Jul 31
Aug 31
Sep 30
Oct 31
1988
157.05
NA
NA
NA
NA
NA
432.57
NA
NA
NA
1989
154.01
NA
NA
NA
NA
NA
440.17
NA
NA
NA
1990
174.69
NA
NA
NA
NA
NA
240.06
NA
NA
NA
1991
162.19
NA
NA
NA
NA
NA
274.94
NA
NA-
NA
1992
166.97
NA
NA
NA
NA
NA
273.54
NA
NA
NA
1993
194.62
NA
NA
NA
NA
NA
252.53
NA
NA
NA
19941995
193.38
NA
NA
NA
NA
NA
339.82
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
1996
200.14
198.53
207.58
212.22
251.44
351.97
517.19
510.31
440.62
259.95
1997
198.41
179.13
196.88
215.57
301.25
538.81
301.68
327.53
300.23
262.93
1998
204.19
182.30
201.02
259.26
400.20
341.88
467.69
378.55
444.45
248.43
1999
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Nov 30 NA NA NA NA NA NA NA NA 186.32 193.52 196.16 NA
Dec 311
Total (MGNR)
NA
2,960.81
NAI
2,809.33 1
NA
2,433.93
NA
2,430.32
NA
2,724.69_
NA
2,456.03
NA
2,908.04
NA
NA
197.97
3,5.34.22
202.78
3,218.70
203.41
3,527.52
NA
NA
Max Month (MGD) 13.95 14.20 7.74 8.87 8.82 8.15 10.96 NA 16.68 17.38 15.09 NA
Min Month (MGD) 5.07 4.97 5.64 5.23 5.39 6.28 6.24 NA 6.01 5.78 5_88 NA
Max Day (MGD) 17.62 18.63 15.77 13.81 21.60 12.37 18.68 NA 22.24 25.28 23.49 NA_
Ave Day (MGD) 8.11 7.70 6.67 6.66 7.46 6.73 7.97 NA 9.68 8.82 9.66 NA
Max Day/Ave Day
Max Month/Ave Day
Min Month/Ave Day
2.17
1.72
0.62
2.42
1,84
0.65
2.36
1.16
0.85
2.07
1.33
0.79
2.89
1.18
0.72
1.84
1.21
0.93
2.34
1.38
0.78
NA
NA
NA
2.30
1.72
0.62
2.87
1.97
0.66
2.43
1.56
0.61
NA
NA
NA
Total Connections
Population Served
13,289
46,700
13,924
51,000
14,343
49,579
14,510
51,000
15,304
52,000
15,882
53,500
16,408
55,000
15973
NA
17,385
57,980
17,757
57,980
18,055
61,500
NA
NA
Total For Capita
Water Use (gpcd) 174 151 134 131 144 126 145 NA 167 152 157 NA
Residential Water Use
MGIYR) 2034.51 1858.92 1340.75 1,261.19 1,809.42 1,560.59 1,867.28 NA 2,347.57 2,085.91 2,274.83 NA
Residential Per Capita
Water Use (gpcd) 119 100 74 68 95 80 93 NA 111 99 101 NA
Max Day Per Capita
Water Use (gpcd) 377 365 318 271 415 231 340 NA 384 436 382 NA
4000
3500
3000
2500
T
0 2000
d
F 1500
1000
500
0
Plymouth Pumping Records
Annual Water Pumped (MG)
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998
Year
9-E-9
T2;• d tr..
r '
dw i.yj' r y•
e
T P r'd? r?'' a ,
r
J r 1.•( a y,°. • 1 •t
i,- f + t. .
a fix, y? r"4t
k•{
s
y
AhtiT T
ItsrHr7 r
r
r.•' r4` ---- ham .
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998
Year
9-E-9
500.00
400.00
T
r=
300.00
a
E
3
a
200.00
100.00
re
Plymouth Monthly Water Pumped
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
19961
1997
01998
9-E-10
Plymouth
1998 Demands by Customer Category
Indus
5°/
Commercial
17%
Institutior
3%
Other
11%
Zesidential
64%
9-E-11
IT Regional
Report,-,
Water Demand and Planning
in the Twin Cities Metropolitan Area
An update to the Long -Term Water Supply Plan
May 2004
it Metropolitan Council
I Metropolitan Council Members
Roger Scherer — District 1
Tony Pistilli — District 2
Mary Hill Smith — District 3
Julius C. Smith — District 4
Russ Susag — District 5
Peggy Leppik — District 6
Annette Meeks — District 7
Lynette Wittsack — District 8
Peter Bell, Chair
Natalie Haas Stephen — District 9
Vacant — District 10
Georgeanne Hilker — District 11
Chris Georgacas — District 12
Richard Aguilar — District 13
Song Lo Fawcett — District 14
Thomas Egan — District 15
Brian McDaniel — District 16
The mission of the Metropolitan Council is to develop, in cooperation with local communities, a
comprehensive regional planning framework, focusing on transportation, wastewater, parks and
aviation systems, that guides the efficient growth of the metropolitan area. The Council operates
transit and wastewater services and administers housing and other grant programs.
Publication no. 32-04-021
ABOUTTHIS REPORT................................................................................................................ iv
INTRODUCTION........................................................................................................................... 1
LegislativeCharge....................................................................................................................... 1
DataCollection............................................................................................................................ 2
MUNICIPAL WATER SUPPLIES................................................................................................. 2
Communities Supplied by Surface Water .................. ............................. 3
Communities Supplied by Groundwater..................................................................................... 4
MUNICIPAL WATER SUPPLY INFRASTRUCTURE................................................................ 5
Wells............................................................................................................................................ 5
Treatmentand Storage................................................................................................................. 6
Interconnections.......................................................................................................................... 7
MUNICIPAL WATER USE........................................................................................................... 7
Overview..................................................................................................................................... 7
Residential Demand and Per Capita Use..................................................................................... 8
Commercial/IndustriaVInstitutional Use................................................................................... 10
Unaccounted/Unmetered........................................................................................................... 11
Overall Use and Relationship to Climate.................................................................................. 11
Maximum Day vs. Average Day Demand................................................................................. 13
WaterPricing............................................................................................................................. 14
WATERCONSERVATION......................................................................................................... 16
WATER SUPPLY ISSUES IN THE TWIN CITIES AREA ........................................................ 16
ForecastedWater Use................................................................................................................ 17
Potential Limitations on Groundwater Supplies........................................................................ 17
Lackof Access to Aquifers................................................................................................... 17
Impact of Groundwater Withdrawals.................................................................................... 18
Contamination of Groundwater Supplies.............................................................................. 20
SurfaceWater Limitations......................................................................................................... 21
TCMA WATER SUPPLY PLANNING....................................................................................... 21
Community Water Supply Plans............................................................................................... 21
Metropolitan Council Water Supply Planning.......................................................................... 22
Other Metro Water Supply Planning Efforts............................................................................. 22
Appropriation Permit Process.................................................................................................... 23
SUMMARY AND RECOMMENDATIONS............................................................................... 23
References..................................................................................................................................... 26
Figure 1 Metropolitan Area Water Supply Source.......................................................................... 3
Figure 2 Metropolitan Area Municipal Wells................................................................................. 5
Figure 3 Generalized Twin Cities Metropolitan Area Geologic Cross -Section .............................. 6
Figure 4 TCMA 2002 Residential Per Capita Demand (in gallons) .............................................. 10
Figure 5 Extent of Prairie du Chien -Jordan Aquifer..................................................................... 19
Table 1 2002 Metro Area Municipal Water Demand...................................................................... 8
Table 2 2002 Metropolitan Water Appropriations.......................................................................... 8
Table 3 Water Price in U.& Cities................................................................................................. 14
Graph 1 Residential Per Capita Per Day Demand and Annual Precipitation .................................. 9
Graph 2 Annual Precipitation and Industrial Water Appropriations ............................................. 11
Graph 3 Metropolitan Area Waterworks Appropriation and Summer Precipitation ..................... 12
Graph 4 Metropolitan Area Municipal Water Use and Temperature ............................................ 13
Graph 5 Metropolitan Area Water Pricing Structures................................................................... 15
APPENDICES
A — TCMA Municipal Water Supply Well Information
B — TCMA Municipal Water System Information
C — 2002 TCMA Municipal Water Use Information
D — TCMA Municipal Water Pricing Information
ii
EXECUTIVE SUMMARY
State law requires the Metropolitan Council to prepare short-term and long-term plans for
existing and expected water use and supply in the Twin Cities metropolitan area
Minnesota Statutes, section 473.156). This report analyzes water demand, issues and
planning conducted for the region, and serves as an update of the water use and supply
element of the Council's Long -Term Water Supply Plan. Water use and water supply
infrastructure information was collected through a variety of sources, including surveys
conducted by the Council.
In 2002, an average of 292 million gallons per day (mgd) of water was used for
municipal supply. Other uses, not including power generation, accounted for another 97
mgd. An additional 774 mgd were appropriated for power generation in 2002; however,
most of this water was used for cooling and returned to the source at a slightly higher
temperature so it is not considered a consumptive use.
No apparent correlation exists between residential per capita water use and average lot
size, average household income or price of water. This study also looks at the potential
relationship between historical use and precipitation and temperature. There is an
apparent relationship between these two factors. Water demand during dry periods is
higher. Approximately 82% of the communities with municipal water supplies in the
region have implemented some water conservation programs.
Potential limitations on the region's water supply include lack of access to the Prairie du
Chien -Jordan aquifer, adverse impacts of withdrawals and contamination. A thorough
assessment of the ability of supplies to meet demands is typically conducted only where a
problem has occurred or is likely to occur. Additional studies are necessary to determine
the full limitations of the region's water supply system.
Finally, this report identifies water supply planning efforts currently under way in the
seven -county area. Each community with a municipal water supply prepares a water
supply plan as part of its local comprehensive plan. These plans commonly lack an
assessment of the ability of the source of supply to meet long-term demands without
adverse impacts. In addition to the local water planning effort, there are some sub -
regional water supply planning efforts under way primarily related to avoiding impacts to
surface water features or source water protection. These studies provide
recommendations for coordinated region -wide water supply planning.
V
ABOUT THIS REPORT
This report was prepared as part of an assessment of the water supply for the Twin Cities
metropolitan area. Much of the information was collected and analyzed by Todd
Reubold, an intern at the Metropolitan Council during Summer 2003. The report was
prepared by Christopher Elvrum of the Metropolitan Council's Environmental Services
Division, Environmental Quality Assessment Department. Questions about the content of
this report can be referred directly to Mr. Elvrum at 651-602-1066 or
christopher.elvru na,,metc.state.mn.us.
Copies of this report can be obtained from the Metropolitan Council's Regional Data
Center (651) 602-1000 or TW (651) 291-0904. This report is pub. no. 32-04-021.
IV
INTRODUCTION
The Twin Cities metropolitan area is fortunate to have a relative abundance of water
resources. These resources were very important to the original development of
Minneapolis and St. Paul, providing power and water for the flour mills, breweries and
other businesses of the growing frontier cities. In addition, the region's water resources
have provided residents with a reliable, potable water source as well as recreational
opportunities. Water resources are critical to the economic viability of the region; the
reliability and availability of water provide the region a competitive advantage.
While overall the region has an adequate supply of water, events such as the drought in
the late 1980s have caused the region to request the U.S. Army Corps of Engineers to
release additional flow from the Upper Mississippi Reservoirs to ensure adequate
supplies for Minneapolis and St. Paul. In the recent past, water supply issues have
developed in response to well interference between neighboring communities, negative
impacts of groundwater appropriation on wetlands and lakes, groundwater contamination,
and situations where communities have concerns about the ability of the resource to
provide adequate water to meet long-term demands. Efforts are under way in the region
to address some of these issues.
The seven -county metropolitan area is projected to grow by 931,000 people between
2000 and 2030. The projected growth and urbanization will generate a higher demand for
water. The increased imperviousness associated with. growth and development may
impact the amount of recharge to the region's aquifers. Urbanization of areas in which
the productive Prairie du Chien -Jordan aquifer is absent will lead to more frequent inter -
community water problems. Natural or human -influenced changes in regional weather
patterns could lead to lower availability of water resources through precipitation
fluctuations, increases in temperature and corresponding increased water demand. The
evaluation of water use detailed in this report is part of the Metropolitan Council's water
supply planning efforts.
Legislative Charge
The Council has various requirements for planning for water supply in the Twin Cities
area. In a general sense, the Council is charged with planning for the orderly and
economic development of the region (Minn. Stats., secs. 473.145 and 473.851). Minn.
Stat., sec. 473.242 allows the Council to undertake research in water supply and initiate
demonstration projects. A more specific requirement for water supply planning (Minn.
Stat., sec. 473.156) was mandated in response to the drought of the late 1980s. This
statute requires the Council to prepare "a short-term and long-term plan for existing and
expected water use and supply in the Metropolitan Area." The long-term plan is to be
continually updated as the need arises." This report details an analysis of the water
demand and supply which is a required element of the Long -Term Water Supply Plan.
Data Collection
Information on water supply and demand was collected through a variety of sources. The
Council requests quarterly water use information by customer category (residential,
commercial, industrial, and institutional) on its sewer survey, which is sent to
communities served by the regional wastewater collection system on an annual basis. As
part of the data collection for this report, an effort was made to collect data for the year
2002 from communities that did not respond to the sewer survey or were not sent a
survey because they are not served by the regional wastewater collection system. The
Council sent a supplemental survey to each municipal supplier requesting information on
its water supply system infrastructure. Approximately 83% of the communities with
municipal water systems submitted the information requested on the surveys.
Additional water use information was obtained from the Minnesota Department of
Natural Resources (DNR), which collects water use information by customer category
annually from each municipal supplier in the state. Information on the amount of water
appropriated for all permitted users is also collected by the DNR and maintained in their
Source Water Users Database System (SWUDS). This was used to fill in information
about the amount of water appropriated from communities that did not submit surveys to
the DNR or Council, and to gather data on water appropriation for categories other than
municipal use. In some cases information about a community's rate structure was
obtained from the community's Web site.
Population and water supply connection information was provided on the surveys. This
was supplemented with data from the Metropolitan Council, Minnesota Department of
Administration and the U.S. Census Bureau. Household information used was from the
Metropolitan Council.
MUNICIPAL WATER SUPPLIES
Within the Twin Cities area at least some portion of 121 communities are supplied by
municipal water. Twenty-three of these communities get their water on a retail or
wholesale basis from other suppliers, leaving a total of 98 separate municipal suppliers.
Both groundwater and surface water serve as the source for municipal and other water
supplies in the region. Total population served (2002) by municipal supply is
approximately 2,481,000. The remaining 227,000 residents are supplied by private wells.
Figure 1 shows the communities with a municipal water supply and their source for
supply.
Groundwater and surface water is also appropriated for uses other than municipal supply
such as industrial processing, irrigation, power generation, water level maintenance and
air conditioning.
hA
Communities Supplied by Surface Water
Sixteen communities in the Twin Cities area are served primarily by surface water
through the Minneapolis Water Works or the St. Paul Regional Water Service. The
Mississippi River is the sole source of water supplied through the Minneapolis Water
Works. The St. Paul Regional Water Service obtains about 70 percent of its water from
Figure 1 Metropolitan Area Water Supply Source
10 5 0 10 20 30 Miles
Supply Source
Groundwater and Surface Water
Groundwater
Minneapolis (Surface Water)
Private Groundwater N I
EM St. Paul (Primarily Surface Water)
the river, and the remainder from four high-capacity groundwater wells, the Rice Creek
Chain of Lakes (Centerville Lake) and tributaries to Vadnais Lake. In 2002 Minneapolis
and St. Paul supplied a total population of approximately 872,000 (32 percent of the
region's population). This number does not include Bloomington, which supplements its
groundwater source with water supplied from Minneapolis, nor does it include a small
amount of service to Edina Morningside.
The Minneapolis Water Works provides all of the water used by the Joint Water
Commission (Crystal, Golden Valley and New Hope), and the cities of Columbia Heights
and Hilltop, on a wholesale basis. The Water Works also supplies water to the
Morningside community in Edina, and up to 30 million gallons per day (mgd) to the City
of Bloomington. It also serves the Minneapolis -St. Paul International Airport and Fort
Snelling. The total population served (2002) by municipal systems that relied directly on
the Minneapolis Water Works is estimated to be 466,000, not including Edina's
Morningside neighborhood or Bloomington.
The St. Paul Regional Water Services supplies water on a wholesale basis to Arden Hills,
Little Canada and Roseville. These communities handle distribution and billing of the
water delivered by St. Paul. Several other cities are retail customers of St. Paul, meaning
that St. Paul does all of the distribution and billing for the cities. Retail customers include
Falcon Heights, Lauderdale, Maplewood, Mendota, Mendota Heights, and West St. Paul.
St. Paul also serves the Minnesota State Fair Grounds. The total population served by
municipal systems that relied directly on the St. Paul Regional Water Service in 2002 is
estimated to be 406,000.
Communities Supplied by Groundwater
Of the 121 communities served by municipal systems, all but the six supplied by
Minneapolis rely to some degree on groundwater as their source. This includes the 10
communities served by the St. Paul Regional Water Services, which supplements its
surface water source with groundwater. Groundwater is obtained from nearly 570 high-
capacity municipal wells located in several prolific aquifers found in the Twin Cities
Basin up to 1,000 feet below the land surface. Figure 2 shows the general locations of the
municipal wells in the region.
Groundwater is the prim source of water to municipal systems, supplying
approximately 1.6 million people (59 percent of the metropolitan area population). This
total does not include the St. Paul Regional Water Service, which uses groundwater as a
supplemental source to the Mississippi River, but does include Bloomington, which uses
groundwater as a primary source. In addition, the 227,000 people with private supplies in
the region rely on groundwater as their source for domestic water. As a primary source,
groundwater supplies over 1.8 million people. When the communities supplied by the St.
Paul Regional Water Service are included, the number served increases to more than 2.2
million people in the Twin Cities area.
4
Figure 2 Metropolitan Area Municipal Wells
0 2 4 8 12 16 20 24Miles
Municipal Water Supply Wells
MUNICIPAL WATER SUPPLY INFRASTRUCTURE
Wells
Municipal wells in the Twin Cities area obtain water from the following aquifers: Prairie
du Chien -Jordan, the Mt. Simon -Hinckley, the Drift and the Franconia -Ironton -Galesville
FIG). At the end of 2002 there were 566 active or standby municipal wells in the region.
Of those, approximately 350 withdrew water from the Prairie du Chien -Jordan Aquifer.
There were between 50 and 60 wells each drawing from the glacial drift, FIG and Mt.
Simon -Hinkley aquifers, with another 40 wells drawing from both the FIG and Mt.
Simon. A few older wells also withdrew water from multiple aquifers. Minnesota Rules,
Chapter 4725 (May 10, 1993), prohibit the construction of multi -aquifer wells as they can
serve as a potential conduit for migration of contamination from across confining layers.
The total pumping capacity of the municipal wells was approximately 894 mgd. This is
more than three times the 2002 average day withdrawal of 290 mgd. However, most
communities experience maximum -day demands that are 2.5 to 3 times the average -day
demand, making the excess capacity necessary to meet the need. As discussed later in this
report, the U. S. Geological Survey (USGS) estimated that 500-800 mgd are available
from the aquifer system in the Twin Cities area. (Schoenberg 1990). Appendix A
contains information on municipal water wells. Figure 3 illustrates the aquifers in a cross-
section view.
Figure 3 Generalized Twin Cities Metropolitan Area Geologic Cross -Section
Feet A we mean sea level
1200 AUNMAPOLIS 'Wizissippi
Glacial Material L Aver I 1 st
1050 Mtmda-jAa Sr.PAUL 1 Getz
1 Riva
900
Decorah -Platteville -Glenwood 1 % /
750
600
450
300
150
0
150
300
P
W
c
0
N
N
0 10 20 30
Miles
40 50 60 70
D Gladal Drift MAquifer EMConfiningLayer
Vertical exaggerationappto3imately 130x
According to the Council's 1997 Metropolitan Area Municipal Water Supply Planning
Process Report (Oberts et al., 1997), in 1996 there were 514 active or standby wells. The
survey conducted for this study indicates that at the end of 2002 there were 566
municipal wells, a net increase of 52 wells in six years. There were actually 57 municipal
wells constructed during this period and 5 abandoned or taken out of service. Of those 57,
36 were completed in the Prairie du Chien -Jordan aquifer, 11 in the FIG aquifer, 6 in the
Mt. Simon -Hinkley aquifer and 4 in the Glacial Drift.
Treatment and Storage
A variety of methods and levels of treatment for both groundwater and surface water are
used in the Twin Cities area. Some suppliers add chlorine and fluorine to water pumped
out of the wells and distribute it to the system. Others provide treatment to remove iron
and manganese or calcium and magnesium. In some cases treatment systems are designed
M
to remove constituents such as radium or trichloroethene to meet drinking water
standards. Other suppliers blend water from wells with high nitrate concentrations with
those with little or no nitrate to reduce concentrations. In addition to softening, the two
surface water suppliers are required by the U.S. Environmental Protection Agency's
EPA) Surface Water Treatment Rule (815-F-98-009) to provide filtration of their water
supplies. All the public water supplies are required to comply with the EPA's Safe
Drinking Water Act, which includes maximum contaminant levels for 87 contaminants.
In Minnesota, the Minnesota Department of Health oversees implementation of the Act.
The total design capacity of all the municipal supply systems in the region is
approximately 1,203 mgd.
Treated municipal water is stored for distribution in reservoirs of varying size and shape
around the region. The reported total storage capacity of all the region's reservoirs is
approximately 667 million gallons. Typically communities design treatment and storage
capacities so that demands can be met while maintaining a volume sufficient for
firefighting and other emergencies. Appendix B contains information about the
community water supply systems.
Interconnections
In addition to the shared supplies and communities that supply other communities, many
of the municipal systems in the Twin Cities area have connections with adjacent
suppliers, primarily for emergencies. Information on interconnections was not collected
for the current study. The Council's 1997 report indicated that a total of 51 communities
participate in 76 emergency connections. This did not include the major service
connections of Minneapolis and St. Paul, nor the regular service of small parts of
communities by others. The report also mentioned that there were many other additional
interconnections being planned or considered by the communities.
The Council will collect updated interconnection information as the communities update
their water supply plans in 2005 and report it in the next update of the Long -Term Water
Supply Plan. Interconnection of supplies and the establishment of agreements helps to
ensure better preparation in the event of a water supply emergency.
MUNICIPAL WATER USE
Overview
In 2002 a total of 107 billion gallons, or approximately 292 mgd, of water were used for
municipal supply in the Twin Cities area. Of this, 61 % or 65.4 billion gallons was used
for residential use. Approximately 29.7 billion gallons was used for
commercial/industrial/institutional supplies. Another 11.7 billion gallons was
unaccounted or unmetered. The average residential per capita daily demand in 2002 was
75 gallons. The overall per capita daily demand was 110 gallons, based on the total
municipal water pumped divided by the total population served. Table 1 presents the
7
region's 2002 municipal water use. Water use for each municipal supplier is contained in
Appendix C.
Table 12002 Metro Area Municipal Water Demand
Residential Use (million gallons) 65,401
CommerciaVIndustrial/Institutional m) 29,687
Unaccounted/Unmetered (m) 11,771
TOTAL (m) 106,859
Average Day Use (m d) 292
Average Residential Per Capita Per Day
gallons)
75
Average Total Per Capita Per Day (gallons) 100
In addition to municipal use, 317.8 billion gallons of water were used in 2002 for
irrigation, power generation, pollution control, air conditioning, water level maintenance
and other non -municipal uses. Of this, more than 282 billion gallons were used for power
generation. About 99% of the volume used for power generation is for cooling and is
returned directly to its source (river) at a slightly higher temperature. Only about 1 % of
the volume used for power generation is considered a consumptive use. Table 2 presents
the 2002 TCMA water use.
Table 2 2.002 Metropolitan Water Appropriations
Use Million Gallons
Municipal Waterworks 105,735
Other Waterworks 1,027
Power Generation 282,530
Air Conditioning 2,229
Industrial 11,573
Temporary 221
Water Level Maintenance 7,205
Special Categories 5,691
Non -Crop Irrigation 3,013
Major Crop Irrigation 4,311
Information for permitted users from the Minnesota Department of Natural Resources Source Water
Users Database System
Residential Demand and Per Capita Use
The average residential water use in 2002 for communities with municipal supplies in the
Twin Cities area was 76.16 gallons per capita, per day (gpcd). The range. of reported use
was 44.6 to 153.6 gpcd. The average use for the year 2002 was the lowest residential per
capita use of the available information (1980, 1988, 1995, 1999, 2000, 2001, and 2002).
In 1980 the residential gpcd was 90 but in 1988, which was a drought year, it was 103
gpcd.
There does not appear to be a trend in the residential per capita use. It does appear that a
relationship exists between residential per capita use and temperature and precipitation.
This is true for overall water demand, as discussed later in this report. Graph 1 shows
residential per capita use and precipitation for years with complete available data.
Graph I Residential Per Capita Per Day Demand and Annual Precipitation
120
100
20
45
40
35
30
d
25
20 3 --+-- Res. GPM
15 e < —
f— Precip.
10
1975 1900 1985 1990 1995 2000 2005
Year
Communities in the region show a wide range of residential per capita water use.
Appendix C). An attempt to draw a correlation between residential use and some other
factor such as lot size, average annual income, price of water or reported conservation
programs was made. It was hypothesized that communities with larger lot size or a more
affluent population would use more water per person. Linear regression analyses were
run on those four factors and residential per capita use. There did not appear to be any
correlation between average lot size, average annual income, price of water or number of
reported conservation programs in a community and per capita water demand. The
relationship between water use and demographics is complex; to accurately determine
this relationship was beyond the scope of this study. Figure 4 shows the 2002 residential
per capita demand across the Twin Cities area.
Figure 4 TCMA 2002 Residential Per Capita Demand (in gallons)
No Data
48-62
63.8 N
81-104 Miles
105-754
0 5 10 20 30 40
Commercial/IndustriaVInstitutional Use
The total commercial/industrial/institutional (c/i/i) use supplied by municipal systems in
2002 was 29.8 billion gallons or 81 mgd. This is an increase of 4.3 billion gallons or 11.9
mgd since 1997 and 9.4 billion gallons or 25.7 mgd since 1980. The amount of use in this
category varies by community across the Twin Cities area. Those communities with
industries that use municipally supplied water have higher use in this category.
Some commercial and industrial users have a source for water supply other than the
municipal systems. In 2002 the reported industrial appropriation for those industries,
which are required to have an appropriation permit (in other words, are not using
municipally supplied water) was 11.6 billion gallons. Use in this category has fluctuated
since 1988 with the highest use of 14.4 billion gallons in 1997. A relationship may exist
between dry years and increased water appropriated for industry. This may be due to
watering of landscaping or other factors. Graph 2 shows the permitted industrial use and
average annual precipitation since 1988. The 2002 c/i/i water use for communities with a
municipal water supply in the region is contained in Appendix C.
ffil
Graph 2 Annual Precipitation and Industrial Water Appropriations
m
8000
cam
4000
0
Year
Unaccounted/Unmetered
35
30 a
25 a —9-- IrdzWal
20
c —*—Avg Predp
15 Q
10
Most of the municipally supplied users in the Twin Cities area are metered. In some cases
meters do not operate properly or are poorly calibrated and do not give accurate data
regarding water use. Uses such as rink flooding, hydrant flushing or landscape watering
of public properties are often unmetered. In addition, some water is lost through leaks in
the water supply system. All of these sources account for the difference in water pumped
and water sold, and are referred to as unaccounted/unmetered. The average percentage of
unaccounted/unmetered uses in 2002 for metropolitan water suppliers was 8.21 %. Some
suppliers reported negative values of water lost, in other words, selling more water than
what was pumped or treated. This is likely a case of faulty meters or accounting errors. In
some cases smaller suppliers can have a significant percentage of their water unaccounted
for due to one main break or during maintenance or repairs. Communities with
unaccounted/unmetered volumes greater than 10% are encouraged by the DNR and
Council to target this category for reduction as part of their conservation programs. The
2002 percent unaccounted/unmetered for each municipal supplier is contained in
Appendix C.
Overall Use and Relationship to Climate
The total water sold by a supplier divided by the total population served is referred to as
the total or overall per capita use. In 2002 the average total per capita use of the
municipal supplies in the Twin Cities area was 100 gpcd. As with the residential per
capita demand, this was the lowest of the available historical data (1980, 1988, 1995,
1999, 2000, 2001, and 2002). The highest average overall per capita demand was in 1988
128 gpcd). In 1980 it was 116 gpcd.
The Minnesota DNR maintains information on the total amount of water appropriated for
those users required to have an appropriation permit going back to 1988. Minnesota Rule
6115.0620 requires a permit for withdrawals of water except among other things, for
domestic uses serving less than 25 persons or less than 10,000 gallons per day or
11
1,000,000 gallons per year. The waterworks use category includes the municipal
suppliers as well as private suppliers of domestic use water that do not meet the
exceptions. Comparing total water appropriated in this category to precipitation shows
that in years with higher summer rainfall there is generally lower municipal water use.
The highest demand in the last 15 years was recorded during the drought of 1988. Water
use dropped in 1989 and 1990 and has slowly rebounded so that municipal water pumped
in 2001, a relatively dry year, was nearly the same volume as 1988. However, the volume
pumped for municipal use in 2002 was more than 11 billion gallons less (8.9%) than that
in 1988, even though the metropolitan population grew by 353,237 from 1990 to 2000.
Graph 3 shows the water pumped for municipal use and summer precipitation from 1988
to 2002.
Graph 3 Metropolitan Area Waterworks Appropriation and Summer Precipitation
380
6360
0
9 340
C
320
A
0 300
a
0.280
E 260
0
240
MA
220
200
25
20
HmLV
15 5
0
A
10 n
1985 1990 1995 2000 2005
Year
mCL
Water Use
f–Precipitation (June -Aug)
It appears that water demand is related to both precipitation and temperature. Vegetation
water needs are related not only to precipitation but also temperature, which together
control evapotranspiration. Water used for landscape watering accounts for a significant
portion of the water produced by municipalities. In the third quarter (July, August,
September) 2002 the water sold in the TCMA was 1.75 times that in the first quarter
January, February, March) and the average maximum -day (typically in the summer) to
average -day ratio was 2.74. In summers with higher temperatures, water use in the
waterworks category is higher. Graph 4 shows the metropolitan water pumped for
waterworks and summer temperatures.
Not only is water demand related to precipitation and temperature, but the frequency or
timeliness of rainfall is also likely a significant factor. Heavy rains with long dry spells
between them may make annual rainfall appear close to normal, but landscape watering
during the dry periods causes elevated water use. A detailed analysis of the trend in water
use and effectiveness of conservation programs would have to take into account detailed
water use information, precipitation, temperature and transpiration data, and was beyond
the scope of this study.
12
Graph 4 Metropolitan Area Municipal Water Use and Temperature
380
340
320
W
coo 300
Q
280
CL
CL
Q 260
a
m 240
220
200
76
74
LL
72 v
CL
E
70 Ha
rn
m
68 m
Q
66
64
4985 4990 4995 2000 2005
Year
Maximum Day vs. Average Day Demand
MGD
Temp (June -Aug)
One way to evaluate water use is to compare average -day and maximum -day water
demand. The maximum -day demand (the volume used on the day of the year with the
highest demand) is most often associated with a hot dry period -when summer lawn
watering is at its peak. Because communities design treatment and storage systems to
meet maximum -day demand, a lower maximum -day demand can help to avoid capital
expenditures that are necessary to meet the demands on only a small number of days. In
communities with smaller systems, the maximum demand can occur on days when water
is used for flushing or maintenance or lost due to a main break. The ratio of the maximum
to average day can be a measure of the effectiveness of some conservation measures
aimed at reducing outdoor water use.
Odd/even water restrictions are often implemented to keep peak use lower. These
restrictions typically allow homes with odd addresses to water outdoors only on odd -
numbered days. If observed and/or enforced only approximately half the residential
population can water their lawns and landscape on a given day. The Twin Cities area
average maximum -day -to -average -day ratio for those communities with an odd/even
sprinkling restriction is 2.78, and for those without it is 2.64. The average residential
gpcd for those communities with an odd/even sprinkling restriction is 76.31 and for those
without it is 74.7. Neither of these differences is statistically significant. Many other
factors influence the maximum -day to average -day ratio and residential per capita use,
but they were not evaluated as part of this study.
A study in Colorado found that in response to a drought in 2002 those communities with
mandatory watering restrictions saved more water than those with voluntary restrictions
Kenney et al.,, in press). Furthermore, those communities with more stringent
13
restrictions reduced water use more than those whose were less stringent. The
communities with watering restricted to once every three days had a reduction in demand
of 22 percent. Those with a twice -a -week limit had an average of 33 percent reduction.
The one community studied with a once -a -week restriction had a 56 percent reduction in
use.
Water Pricing
In 2002 in the Twin Cities area, the average cost of water for 30,000 gallons in three
months was $57.71 or $1.92 per 1,000 gallons. The range was from $22.50 to $112.50.
This takes into consideration base use fees and other monthly charges. The rate for water
in this region is comparable to other communities across the United States. Table 3 shows
the price per 10,000 gallons for several U.S. cities. Appendix D contains the water
pricing structures for Twin Cities area communities.
The price per 30,000 gallons was compared to residential per capita demand in the
region. It was thought that communities with lower water rates might have higher per
capita use. However, there was no apparent correlation between price per 30,000 gallons
and residential per capita use.
Of the 103 communities that reported pricing structures in the region, 60 had uniform rate
structures, 28 had increasing block rates, 6 had decreasing block and 9 had other types of
rate structures. The uniform rate is a constant rate per 1,000 gallons regardless of use. In
an increasing block rate structure, the price per 1,000 gallons increases as use increases,
usually at various cutoff amounts such as an increase of $0.20 per 1,000 gallons if more
than 20,000 gallons are used during a billing period.
Table 3 Water Price in U.S. Cities
City Price per 10,000 gallons (including
base fees and additional charges)
Milwaukee 10.90
Chicago 12.35
Madison, WI 15.46
Las Vegas 18.21
Denver 18.31
New York 20.32
St. Paul 22.72
San Francisco 23.92
Atlanta 25.87
Portland 26.05
Duluth, MN 26.63
Minneapolis 27.70
Phoenix 32.46
San Diego 32.94
Los Angeles 37.03
Seattle 45.37
Pittsburgh 51.73
information collected from city Web sites
Most of the decreasing block rates reported had a relatively high base rate for the first
10,000 gallons, with a price per 1,000 gallons that was lower than what it would cost for
14
the first 10,000 if the base price were divided by 10,000. For example, one community
charges a minimum of $17.72, and for every 1,000 gallons over 10,000 gallons $1.62 is
charged. So, although the community may consider it a uniform rate, essentially the price
per 1,000 gallons of the first 10,000 gallons is $1.72 and $1.62 thereafter. Most of the
other rate structures were seasonal rates resulting in higher rates during the summer.
Presumably these rate structures are typically adopted to discourage use during the high -
use periods in summer.
50.00%
70.00%
60.00%
50.00%
40.00%
30.00%
20.00%
10.00%
0.00%
Graph 5 Metropolitan Area Water Pricing Structures
Uniform Flat Decreasing Block Increasing Block Mixed
Rate Structure
M Percentage -1991 Percentage -1996 13 Percentage - 2002
A comparison of the current rate structures to past rate structures shows that a higher
percentage of rate structures in 2002 were increasing block and a lower percentage were
decreasing block. This may be due to 1993 amendments to Minn. Stats., secs. 103G.291
and 473.851, which required water suppliers to employ water -use demand reduction
measures including evaluation of a conservation rate structure. Graph 4 shows the change
in percent of rate structures over time.
15
WATER CONSERVATION
Minnesota Statute, mandates that a water supply plan be prepared for each of the
communities in the metropolitan area with a municipal water supply system (Minn. Stat.
sec. 473.859 subd. 3(4)). One component of these plans is a water conservation plan.
Some communities had conservation methods in place prior to preparation of their plans.
Others implemented programs in response to preparation of the plans, while others met
the requirement to prepare a plan but have not implemented conservation programs to
date.
Of the 95 communities responding to the Council's surveys, approximately 82% reported
having some conservation program(s) in place in 2002. The programs often include a mix
of practices. Of those responding, 40% reported having an education program, 50%
having watering restrictions, 33% having conservation pricing and 10% reported having
leak detection and repair as a conservation method.
There was no apparent correlation between residential per capita water demand and
communities with or without conservation programs. One of the factors that would
contribute to this is variability of a given conservation method. For instance, several
communities reported having water conservation education programs. The extent of these
programs is likely highly variable. One community may use bill stuffers while another
may use Web sites or local newspapers to educate consumers.
It is difficult to evaluate the effectiveness of conservation programs over time as weather
variations make predicting water use difficult. It is true that during hot dry summers,
water use is higher. Another factor necessary for effective evaluation is the timing and
frequency of rainfall. In order to completely take climate into account, a multivariate
analysis would need to be conducted. This may be most effectively done on selected
communities with detailed historic water use and conservation program methods.
Another approach would be to compare winter use over time. This would allow an
analysis of indoor conservation practices.
As previously mentioned, an in-depth study on the effectiveness of water conservation
for reducing demand in the Twin Cities area was not conducted as part of this study. It
should, however, be undertaken as a future study. Water conservation has been shown to
be effective at reducing water use in other communities in the United States. Several case
studies are outlined in Cases in Water Conservation: How Efficiency Programs Help
Water Utilities Save Water and Avoid Costs (USEPA, 2002). Most of these cases discuss
the conservation program used and the resulting reduction in use but do not describe in
detail how factors such as weather patterns were taken into consideration when assessing
effectiveness of the conservation program.
WATER SUPPLY ISSUES IN THE TWIN CITIES AREA
The Twin Cities area is fortunate to have a relatively abundant supply of water of good
quality. This condition was very important to the original development of Minneapolis
16
and St. Paul. and continues to provide a competitive advantage to the region. Water
supplies are not, however, limitless. At times, droughts have caused the region to request
the U.S. Army Corps of Engineers to release additional flow from the Upper Mississippi
Reservoirs to ensure adequate supplies for Minneapolis and St. Paul. Communities
routinely impose water use restrictions during dry periods to reduce demand on the
supply source and system. There are also more frequent inter -community issues relating
to water supply that result from well interferences, negative impacts of groundwater
appropriation on wetlands and lakes or inability of an aquifer to meet the needs of the
community. Contamination can also affect the availability of groundwater and surface
water supplies.
Forecast Water Use
Water demand forecasts were prepared for each metropolitan community as part of the
Council's Long -Term Water Supply Plan (Elvrum, 2001). Based on that study,
residential, commercial, industrial and institutional water use is forecasted to reach 517
million gallons per day in 2040, a 35 percent or 133 mgd increase from 2000 to 2040.
However, water use for agriculture, water -level maintenance and once -through air
conditioning is projected to decrease during the same period. Water demand for power
generation is expected to remain relatively constant over the 40 -year period. Total water
demand, including power generation, is forecasted to reach over 1.2 billion gallons a day
in 2040, an overall increase of 100 mgd, or about 10 percent. Much of the projected
increase in water use is expected to be in the developing suburbs where significant
residential and commercial growth is forecast.
Potential Limitations on Groundwater Supplies
A variety of factors could limit available groundwater in the Twin Cities area. These
include lack of access to the highly prolific Prairie du Chien -Jordan Aquifer, impact of
groundwater withdrawals on surface water features or other wells, lack of understanding
of maximum limit on groundwater supply in an area and contaminated supplies.
Lack of Access to Aquifers
Due to the nature of the geology of the Twin City basin the prolific Prairie du Chien -
Jordan Aquifer is not present in much of the north and western portions of the region.
The aquifers available in these areas include the surficial aquifer, the FIG and the Mt.
Simon/Hinkley. In some areas the surficial aquifer produces significant quantities of
water for supply. However, this aquifer is highly variable and, because of its proximity to
the land surface, it is more susceptible to contamination, variations in precipitation and
may be more quickly affected by decreased recharge due to increasing impervious
surface. The FIG aquifer is used in many areas of the region. Although there are some
relatively high capacity wells in the FIG aquifer, it has highly variable and generally
lower capacities than the Prairie du Chien -Jordan aquifer. The Mt. Simon/Hinkley aquifer
is also a potential source for water in the region, however, legal limitations have been
imposed on its usage. Minn. Stat., sec. 103G.271 Subd.4a does not allow new
17
appropriation permits for water from the Mt. Simon/Hinkley aquifer unless there are no
feasible or practical alternatives to this source and only if it is appropriated for domestic
use. Figure 5 shows the extent of the Prairie du Chien -Jordan aquifer.
Impact of Groundwater Withdrawals
There are cases in the Twin Cities area where groundwater withdrawals either have had
an impact, or there was a concern that they would have an impact, on surface waters. In
cases where an impact has or is likely to occur, the DNR may limit groundwater
withdrawals to eliminate or minimize the effect. Impacts on private wells from municipal
wells have been recently documented in the region. In most cases, an evaluation of
potential impacts on surface waters is not conducted as part of a community's water
supply planning process.
The southwest metropolitan area is an example where impacts on surface water features
from groundwater withdrawals were documented. The Savage Fen wetland complex
contains a rare calcareous fen and it was determined that groundwater withdrawals were
adversely impacting this natural resource. Limitations on appropriations, especially in
Savage, were implemented to avoid further degradation. Other surface water features in
the area (Eagle Creek, Boiling Spring, Deans Lake, Black Dog Fen, Nichols Fen) raised
additional concern and led to significant planning and cooperation efforts through the
Southwest Metro Groundwater Work Group.
In another case, a proposed well field for the eastern portion of the City of Woodbury
raised concerns about the potential impact on the downgradient Valley Creek, a trout
stream, as well as nearby private wells. The City of Woodbury is conducting tests and
performing modeling to evaluate potential impacts.
18
Figure 5 Extent of Prairie du Chien -Jordan Aquifer
10 5 0 10 20 30 Miles
Extent of Prairie du Chien -Jordan Aquifer
N
Withdrawals from high-capacity wells, typically during high -use periods (summer), can
lower water levels in shallower private wells; such an example was reported in 2001 in
the Lakeville/Credit River Township area. Heavy groundwater withdrawals during a hot
dry period in summer 2001 caused drawdown in some private wells to levels below their
pumps. Additional interference issues could arise as urbanization expands into rural
areas. Lowering overall and peak use through water conservation and proper siting of
wells may help to avoid conflicts.
The maximum limit on regional groundwater supply is not well defined. The most recent
attempt to quantify the amount of water that can be withdrawn from the aquifer system
was conducted in the 1980s by the USGS (Schoenberg 1990). The study estimated that a
maximum of 500-800 million gallons per day were available from the aquifer system.
This assessment did not take into account local conditions such as potential adverse
impacts on surface waters or other wells, which can limit withdrawals. Additionally, it
did not consider increasing impervious surface and present concerns for climate changes.
19
Contamination of Groundwater Supplies
In some areas groundwater is contaminated by contaminants introduced at the land
surface and/or by natural compounds in geologic materials. Some contaminants found in
groundwater in the Twin Cities area include nitrate, radium and trichloroethene. Nitrate
can be found naturally, but elevated levels are most often related to land use. Agricultural
and other fertilizers, as well as septic systems, can elevate nitrate concentrations in
groundwater to above the drinking water standard of 10 mg/L. Radium, which occurs
naturally in some areas of the bedrock aquifers in the region, can also reach
concentrations above standards. Solvents and other mars -made compounds are found in
aquifers due to past land uses. Contamination from the Twin Cities Army Ammunition
Plant reached wells for the City of New Brighton, which now treats the water and uses it
as potable water supply. The wells are also part of the groundwater cleanup system for
the site. Recently a contaminant plume in the Baytown Township area has impacted
several private wells and has reached a municipal well for the City of Bayport.
Information from the Minnesota Pollution Control Agency reported in the Council's 1992
Water Supply: A Plan For Action report estimated that there are 230 billion gallons of
contaminated groundwater underlying the Twin Cities area. This was about 8% of the
available 2,845 billion gallons in the aquifers evaluated (Oberts et al., 1992).
Aquifer Recharge and Impervious Surface
An increase in impervious surface could result in a reduction in infiltration, which
recharges aquifers. In addition, increasing impervious surface increases run-off, which
can carry pollutants and increase flooding. A recent study evaluated the amount of
surface no longer available for recharge due to additional impervious surface for several
metropolitan areas in the United States (Otto et al., 2002). The report estimated the loss
of yearly infiltration between 1982 and 1997 in the Twin Cities area at 9.0 to 21.1 billion
gallons. Newcomb et al., (2002) determined that groundwater recharge was reduced in
130 of 136 subwatersheds of the Raritan River Basin between 1986 and 1995 due to land -
use changes. Others have suggested that as areas urbanize an increase in infiltration can
occur as a result of leaky water and wastewater pipes and increased landscape watering
Lerner 2002, Foster 1996). The Council estimates that 180,000 acres in the Twin Cities
area will be urbanized between 2000 and 2030.
A study currently under way by the USGS and Council will examine the changes in
groundwater recharge due to increased impervious surface. Recent efforts to utilize
alternative storm water management methods, such as rain gardens, to benefit surface
water quality may also act to lower the impact of impervious surface by allowing
infiltration of rainwater. The potential groundwater quality impacts from infiltration of
stormwater in rain gardens is also being studied by the USGS with funding from the
Council.
20
Drought
High water demands for lawn watering during hot dry periods place pressure on the
aquifer system and treatment/supply systems. During these periods, impacts may be felt
on other groundwater users and natural resources that are also in need of higher quantities
of water. A corresponding reduction in recharge occurs which may not be immediately
felt in bedrock aquifers but can effect shallow supply wells and have a long-term impact
on deeper aquifers.
Surface Water Limitations
Drought can lower Mississippi River levels enough to cause concern for the suppliers
who use surface water as their source. In the last 30 years there have been two drought
periods, 1976-77 and 1988, which have caused concern for the Minneapolis and St. Paul
water supplies. There are other uses such as navigation, wastewater assimilation and
power generation which rely on a minimum flow for proper operation. In all but the most
severe drought conditions the flow in the Mississippi River would likely be sufficient to
supply water for the Minneapolis Water Works and St. Paul Regional Water Service.
However, climate changes could affect the reliability of the Mississippi in the future. The
Council's Short -Term Water Supply Plan discusses the various river uses and minimum
needs during drought conditions (Metropolitan Council, 1990).
The exposure of surface waters, such as the Mississippi River, to the land surface leaves
them susceptible to contamination. Many potential sources for point and non -point
contamination exist in the watershed that lies above the Minneapolis and St. Paul intakes.
Depending on several factors, including river stage and contaminant type and volume, the
suppliers may deal with contaminants through treatment or temporary shutdown of
intakes. Unlike groundwater sources, the management of the source area for surface
waters covers an extremely large area and several jurisdictions. Efforts are under way to
coordinate source water protection planning for Minneapolis, St. Paul and St. Cloud, the
major water suppliers using the Mississippi River in Minnesota.
METRO AREA WATER SUPPLY PLANNING
Community Water Supply Plans
Each Twin Cities area community with a municipal water supply is required to prepare a
water supply plan. These plans meet the requirements of the DNB's Emergency and
Conservation Plan, Minn. Stat., sec. 103G.291, as well the water supply plan required as
part of the local comprehensive plan, Minn. Stat., sec. 473.859.
There is a wide range of detail and content in the water supply plans prepared by each
community in the Twin Cities area. Most of the plans contain a thorough description of
the supply system and past and forecasted water use. Each plan is required to contain an
emergency and conservation plan, some of which are very detailed and aggressive while
others barely meet the minimum requirements. One aspect that lacks detail in these plans
21
is the analysis of the source of supply. A thorough assessment of the water supply source
and its ability to supply projected demands without adverse impacts has typically been
beyond the scope of the community water supply plans. The plans also only focus on the
individual system and do not assess the resource from a regional perspective.
Metropolitan Council Water Supply Planning
The Metropolitan Council is required by Minn. Stat., sec. 473.156 to periodically prepare
updates to the Long -Term Water Supply Plan. This report serves as an update to the
metropolitan area water supply and use aspect of the Council's long-term plan. Other
reports have been prepared which detail regional water use and present water demand
projections for the region. The Council is also involved in other efforts to assess and plan
for water supplies in the area.
The Council has facilitated the Southwest Metro Groundwater Work Group since 1997.
As previously mentioned, concerns for the impact of groundwater withdrawals on surface
water features led to this cooperative planning effort in the southwest metropolitan area.
The group has served as an informal forum for sharing information and discussing each
community's development of plans for supplying water while protecting surface water
features. Through the group, agreements between the DNR and water suppliers have been
developed to deal with immediate and future water appropriation needs. Arrangements
between the communities for sharing supplies on a limited basis have been reached and
discussions on long-term cooperation continue. A management plan was completed in
2002, and the parties are in the process of signing a memorandum of agreement to
continue to work together. The agreement also establishes goals to work toward.
In addition to this subregional planning effort, the Council has assumed responsibility for
the Metro Area Groundwater Model developed by the Minnesota Pollution Control
Agency (MPCA). This model and its corresponding databases are used for many
groundwater modeling activities in the region. The Council is currently refining the
model for the northwest metro area where significant growth is planned along the I-94
corridor and the Prairie du Chien -Jordan Aquifer is not available. The Council intends to
use the model to assess the ability of the available aquifers to supply projected demand in
the area. In addition, a Northwest Metro Water Supply Work Group will be established to
address water supply issues in the area. The effort in the southwest metro will serve as a
model for cooperative water supply planning in the northwest metro and other areas of
the region.
Other Metro Water Supply Planning Efforts
Other sub -regional water supply planning efforts are under way in and around the Twin
Cities area. One of these is a Technical Advisory Committee that has been formed to
evaluate and avoid potential impact to a trout stream and private wells from a proposed
municipal well field in eastern Woodbury. The City of Woodbury and Washington
County are coordinating technical studies with cooperation from the Council, DNR,
watershed districts and others.
22
In another water supply planning effort, a group consisting of the Minnesota Department
of Health, DNR, Metropolitan Council, the MPCA and others, together with the cities of
Minneapolis, St. Paul, and St. Cloud, coordinate efforts to protect the Mississippi River,
the source of water for those cities. The group is currently assisting with the development
of source water protection plans for each of the suppliers. An early effort of a similar
group, the River Defense Network, coordinated the placement of and associated training
for spill response equipment along the Mississippi River upstream of the Minneapolis, St.
Paul and St. Cloud water supply intakes.
Appropriation Permit Process
Prior to construction of a well for water supply, a permit from the Minnesota Department
of Health has to be obtained. This permit is concerned mainly with proper well
construction and placement for public health concerns. Once the well is in place, a permit
for appropriation of the water is requested from the DNR. The Council reviews these
permits in order to ensure that they are consistent with the community's water supply
plan. Delays in obtaining the appropriation permit can occur if concerns are raised about
the impact of the well on other resources, if a community has relatively high per capita
use and little conservation, or if the community's water supply plan is incomplete.
SUMMARY AND RECOMMENDATIONS
At least some portion of 121 communities in the Twin Cities area is supplied by
municipal water. Groundwater is the primary source for about 1.6 million municipal
water users. Groundwater is also the sole source to about 230,000 users relying on private
wells. The Mississippi River supplies approximately 870,000 users in the region.
Approximately 384 million gallons per day are used for municipally and non -municipally
supplied residential, commercial, industrial and institutional uses. Currently, about 1.1
billion gallons a day are needed to meet the total demand, including power generation, of
the metropolitan area. Residential, commercial, industrial and institutional water use is
projected to grow to 517 mgd by 2040, a 35% increase from 2000.
There are nearly 570 municipal water supply wells in the region. The total capacity of all
the municipal wells is 870 million gallons per day. The total design capacity of the
treatment systems is 1,200 million gallons per day. The total storage of the water supply
systems is 667 million gallons.
Most communities in the region have implemented some water conservation programs. A
correlation between water use and conservation programs, lot size, average annual
income and water price was not found. There is a connection between water use and
weather. A detailed analysis of weather and conservation programs is necessary to
determine the effectiveness of conservation.
The Twin Cities area has relatively abundant water resources. However, these supplies
are not without limitation. Lack of access to prolific aquifers for urban expansions,
contamination, adverse impacts of withdrawals and reduced recharge due to climate
23
change, drought and increased impervious surface are some of the potential issues that
could limit water supplies.
Local and subregional planning efforts are under way to ensure the long-term viability of
the water supply resources. Cooperative efforts such as the Southwest Metro
Groundwater Work Group and the Woodbury/Afton Groundwater Study show how
multiple entities with a variety of responsibilities can work together to plan for adequate
supplies while avoiding adverse impacts.
However, the seven -county region and state lack a coordinated, comprehensive, region -
wide water supply planning program. Currently little assessment exists of the ability of
the water resources to supply the projected demand without adverse impacts, except in
areas where an impact has or is likely to occur. With relatively abundant water supplies in
the region, growth would not likely have to be limited where local supplies are not
sufficient as long as coordinated planning and sufficient funding is available to bring
water to an area. A coordinated effort to determine the availability of water prior to
investment in other types of infrastructure will help to avoid potential future conflicts and
degradation of the resource. In addition, prior analysis of the source of supply and
development of a plan with the DNR to serve long-term demands without adverse
impacts, would help streamline the water appropriation permit process so that
communities could receive permits without delay.
As the region accommodates a larger population and a greater degree of urbanization, the
higher demand for water, lower recharge resulting from more imperviousness, and
urbanization of areas in which our most productive aquifer is absent will lead to more
frequent inter -community water problems. Natural and/or human -influenced climate
change could lead to lower availability of water resources through changes to regional
weather patterns and thereby precipitation, and to increases in water demand through
higher evapotranspiration, the result of higher temperatures, thus exacerbating the
problems.
In order to maintain its competitive edge and minimize the frequency of water problems,
the region needs to:
Develop a clear understanding of the existing water supply available at a sustainable
level and develop a plan to ensure that the resources are available where needed prior
to development.
Create an institutional framework that will provide for a regional and sub -regional
approach to planning and coordination of water supply management, and to the
development of solutions to problems.
Develop a funding mechanism that ensures that the region can continuously manage
its water supplies appropriately.
24
These proposed efforts would be in addition to the water -use information evaluation and
water -demand projections that the Council and others currently conduct. Within the
seven -county area, the Metropolitan Council would be the logical entity to lead a
coordinated water supply planning effort with participation from local and state entities.
However, water resources do not recognize political boundaries, and significant growth
in the areas bordering the Twin Cities area will have impacts on the resources and
significantly influence the demand within the region. Therefore, cooperation from
surrounding communities and counties, as well as the regulatory capacities of state
agencies, would be necessary to adequately plan for the region's water supply.
25
Agenda Number: 3
TO: Mayor and City Council 1 ;
FROM: Laurie Ahrens, City Manager
SUBJECT: Set Future Study Sessions
DATE: July 20, 2004, for City Council study session of July 27, 2004
1. ACTION REQUESTED: Review the pending study session topics list and, if desired,
establish future special meetings or amend the topics list.
Mayor Johnson has suggested that the City Council consider establishing a special meeting to
meet with the local legislative delegation regarding transportation issues. If the Council
wishes to hold this meeting and could provide us with several dates, we will contact the
legislative delegation to request a meeting.
2. BACKGROUND: Attached is the list of pending study session topics, as well as calendars
to assist in scheduling.
Pending Study Session Topics
at least 3 Council members have approved the following study items on the list)
Review City Center concept, parking, downtown council, signage
issues (Council)
Review Development/Redevelopment Application Process
Council)
Other requests for study session topics:
Update with City Manager — quarterly (next mtg. fall)
Discuss requests for City membership in organizations, such as
North Metro Mayors Assn., NLC, US Conference of Mayors
Johnson)
Paper Conservation "paperless agendas" (Slavik) Jan.
Consider resident/resident water issues relating to sump pump
discharge (Slavik)
OFFICIAL CITY MEETINGS
August 2004
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
1 2 3 4 5 6 7
5:30 PM 7:00 PM
NATIONAL NIGHT PLANNING
OUT COMMISSION,
Council Chambers
8 9 10 11 12 13 14
5:30 PM SPECIAL
MEETING: Reception
for Surface Water Task
Force, Lunch Room
7:00 PM SPECIAL
COUNCIL MEETING:
Recehe Surface Water
Task Force Report,
COUnCII Chambers
5:30 PM SPECIAL CITY
COUNCIL MEETING:
JOINT MEETING WITH
CHARTER
COMMISSION; Public
Safety Training Room
7.0o PM REGULAR
COUNCIL MEETING,
Counal Clmmbsn
7:00 PM
ENVIRONMENTAL
QUALITY CMENTAE
EQC), Council
Chambers
7:00 PM PARK &
REC ADVISORY
COMMISSION
PRAC), Council
Chambers
15 16 17 18 19 20 21
6:45 PM YOUTH
ADVISORY
COUNCIL, Council
Chambers
7:00 PM
PLANNING
COMMISSION,
Council Chambers
7:00 PM HOUSING &
REDEVELOPMENT
AUTHORITY (HRA),
Medicine Lake Room
22 23 24 25 26 27 28
7:00 PM SPECIAL 7:01 PM REGULAR 7:00 PM
COUNCIL
COUNCIL MEETING,
PLYMOUTH
MEETING: Budget ADVISORY
Study Session, COMMITTEE ON
Public Safety TRANSIT (PACT) -
Training Room Medicine Lake
Room
29 30
6:45 PM YOUTH
ADVISORY
COUNCIL, Council
31
Jul 2004
S M T W T F S
1 2 3
Sep 2004
S M T W T F S
1 2 3 4
7:00 PM SPECIAL
COUNCIL
MEETING: Budget
Chambers Studay Session, 4 5 6 7 8 9 10 5 6 7 8 9 10 11
Public Safety
Training Room 11 12 13 14 15 16 17
18 19 20 21 22 23 24
12 13 14 15 16 17 18
19 20 21 22 23 24 25
25 26 27 28 29 30 31 26 27 28 29 30
modified on 7/20/2004
OFFICIAL CITY MEETINGS
September 2004
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
1 2 3 4
Aug 2004
S M T W T F S
Oct 2004
S M T W T F S
1 2
7:00 PM
PLANNING
COMMISSION,
7:00 PM HUMAN
RIGHTS
COMMISSION - 1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
3 4 5 6 7 8 9
10 11 12 13 14 15 16
Council Chambers Medicine Lake
Room
22 23 24 25 26 27 28 17 18 19 20 21 22 23
29 30 31 24 25 26 27 28 29 30
31
5 6 7 8 9 10 11
LABOR DAY - City
Offices Closed
7:00
ENVIRONMENTAL
ouALrrvcoMMrrrEE
EOC),CounG
chambers
7:00 PM PARK &
REC ADVISORY
COMMISSION
PRAC), Council
7:00 PM SPECIAL
COUNCIL
MEETING: Budgetg
Study Session,
Public Safety Chambers
Training Room
12 13 14 15 16 17 18
6:45 PM YOUTH
ADVISORY COUNCIL,
Council Chambers
PRIMARY
ELECTION
DAY - Polls are
Rosh Hashanah
begins at sunset
7:00 PM HOUSING&
REDEVELOPMENT
AUTHORITY (HRA),
Medicine Lake Room
7:00 PM REGULAR
COUNCIL MEETING,
C_.C..E .
open 7 AM - 8
PM
CITYHALL OPEN
UNTIL 7:00 PM FOR
ABSENTEE VOTING
19 20 21 22 23 24 25
7:00 PM PLANNING
COMMISSION, Counc l
Chambers
Yom Kippur
begins at sunset
9:00 AM
PLYMOUTH
CLEAN-UP DAV,
7:00 PM PLYMOUTH
ADVIsoRY
COMMnTEE ON
TRANSR(PACT) -
Medicine Lake Room
Public Works
Maintenance
Facility
26 27 28 29 30
6:45 PM YOUTH 11:45 AM PLYMOUTH
BUSINESS COUNCIL,
ADVISORY
COUNCIL, Council
sl.,.mnM..PorW.a
12201 Rklp.d.l. Drive,
M:v.mnk.
Chambers
7'00 PM REGULAR
COUNCIL MEETING,
Cound Ch_lm.
modified on 7/20/2004
OFFICIAL CITY MEETINGS
October 2004
Sunday Monday Tuesday I Wednesday Thursday Friday Saturday
Sep 2004 Nov 2004 1 2
S M T W T F S S M T W T F S 1:00 PM
1 2 3 4 1 2 3 4 5 6
5 6 7 8 9 10 11 7 8 9 10 11 12 13
PLYMOUTH ON
PARADE
12 13 14 15 16 17 18 14 15 16 17 18 19 20
19 20 21 22 23 24 25 21 22 23 24 25 26 27
26 27 28 29 30 28 29 30
3 4 5 6 7 8 9
7:00 PM 7:00 PM HUMAN
PLANNING RIGHTS
COMMISSION, COMMISSION -
Council Chambers Medicine Lake
Room
10 11 12 13 14 15 16
6:45 PM YOUTH7:00
ADVISORY COUNCIL,
Council Chambers
PM REGULAR
COUNCIL MEETING,
Co-cl Clamber
7:00 PM
ENVIRONMENTAL
QUALITY COMMITTEE
QC), Council
Chambers
7:00 PM PARK &
REC ADVISORY
COMMISSION
PRAC), Council
Chambers
COLUMBUS DAY
OBSERVED), Public
Works Dhision closed
LEAGUE OF MINNESOTA CRIES ANNUAL CONFERENCE, Duluth
17 18 19 20 21 22 23
7:00 PM
PLANNING
COMMISSION,
Council Chambers
7:00 PM HOUSING b
REDEVELOPMENT
AUTHORITY (HRA),
Medicine Lake Room
24 25 26 27 28 29 30
6:45 PM YOUTH i7:00 PM REGULAR 7:00 PM 6:00 PM 9:00 AM -3:00
ADVISORY
COUNCIL, Council
Chambers
CC-1Ch.mb.,. PLYMOUTH
ADVISORY
COMMITTEE ON
TRANSIT (PACT) -
Medicine Lake
Room
VOLUNTEER
RECOGNITION
EVENT,
Plymouth Creek
Center
PM CITY HALL
OPEN FOR
ABSENTEE
VOTING
31
DAYLIGHT
SAVINGS ENDS -
set clocks back 1
hour
modified on 7/20/2004
OFFICIAL CITY MEETINGS
November 2004
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
1 2 3 4 5 6
CITY OFFICES GENERAL 7:00 PM 7:00 PM HUMAN
OPEN UNTIL
7:00 PM FOR
ABSENTEE
VOTING
ELECTION -
Polls open 7 AM
dose 8 PM
PLANNING
COMMISSION,
Council Chambers
RIGHTS
COMMISSION -
Medicine Lake
Room
7 8 9 10 11 12 13
6:45 PM YOUTH
ADVISORY
COUNCIL, Council
Chambers
7:00 PM REGULAR
COUNCIL MEETING,
CeundlChamhen
7:00 PM
ENVIRONMENTAL
UALI YCOMMITTEE
Eoc), council
chambers
7:00 PM PARK &
REC ADVISORY
COMMISSION
PRAC), Council
Chambers
VETERANS DAY
OBSERVED),
City Offices
Closed
14 15 16 17 18 19 20
7:00 PM
PLANNING
COMMISSION,
7:00 PM HOUSING 8
REDEVELOPMENT
AUTHORITY (HRA),
Medickie Lake Room
Council Chambers
21 22 23 24 25 26 27
6:45 PM YOUTH 11.45 AM PLYMOUTH 7:00 PM City Offices City Offices
ADVISORY
COUNCIL, Council
Sh_' Mxne.P.I. W.
13201 RWWd.W Da ,
Mnnebnk.
PLYMOUTH
ADVISORY
dosed dosed
Chambers
7-00 PM REGULAR
COUNCIL MEETING.
COMMITTEE ON
TRANSIT (PACT) -
Medicine Lake
THANKSGIVING
HOLIDAY
THANKSGIVING
HOLIDAY
C—dCh..b.. Room
28 29 30 Dec 2004Oct2004
S M T W T F S S M TW T F S
1 2 1 2 3 4
3 4 5 6 7 8 9 5 6 7 8 9 10 11
10 11 12 13 14 15 16 12 13 14 15 16 17 18
17 18 19 20 21 22 23 19 20 21 22 23 24 25
24 25 26 27 28 29 30 26 27 28 29 30 31
31
modified on 7/20/2004
OFFICIAL CITY MEETINGS
December 2004
Sunday Monday I Tuesday Wednesday Thursday Friday Saturday
1
7:00 PM
PLANNING
COMMISSION,
2
7:00 PM HUMAN
RIGHTS
COMMISSION -
3 4
Nov 2004
S M T W T F S
Jan 2005
S M T W T F S
1 2 3 4 5 6 1
7 8 9 10 11 12 13
14 15 16 17 18 19 20
2 3 4 5 6 7 8
9 10 11 12 13 14 15
Council Chambers Medicine Lake
Room
21 22 23 24 25 26 27 16 17 18 19 20 21 22
28 29 30 23 24 25 26 27 28 29
30 31
5 6 7 8 9 10 11
6:45 PM YOUTH
ADVISORY
COUNCIL, Council
Chambers
Channukah
begins at sunset
7:00 PM
ENVIRONMENTAL
pUALRY COMMITTEE
EQC), Cound
Chambers
7:00 PM PARK &
REC ADVISORY
COMMISSION
PRAC), Council
Chambers
12 13 14 15 16 17 18
700 PM REGULAR
couNCILMEEnNG.
co ecn.n,ben
7:00 PM
PLANNING
COMMISSION,
Council Chambers
7:00 PM HOUSING 8
REDEVELOPMENT
AUTHORITY(HRA),
Medicine Lake Room
19 20 21 22 23 24 25
6:45 PM YOUTH 7:00 PM CITY OFFICES CHRISTMAS
ADVISORY PLYMOUTH CLOSE AT HOLIDAY
COUNCIL, Council
Chambers
ADVISORY
COMMITTEE ON
TRANSIT (PACT) -
Medicine Lake
Room
NOON IN
OBSERVANCE
OF THE
CHRISTMAS
HOLIDAY
26 27 28 29 30 31
790 PM REGULAR
COUNCIL MEETING,
Co"d Ch_b—
modified on 7/20/2004