HomeMy WebLinkAbout2.0 Impact of Changes to the Public Water Supply Wells
2.0 Impact of Changes to the Public
Water Supply Wells
In accordance with the requirements of Minnesota Rules 4720.5220, anticipated changes in the
physical environment, land use, surface water, and groundwater within the DWSMAs within the next
10 years and the impact of these changes on the source water aquifer are discussed in this section.
2.1 Potential Changes Identified
2.1.1 Physical Environment
Currently, significant or large-scale changes in the physical environment within the DWSMAs, are not
anticipated in the next lO years or the life of this Plan. Changes to existing municipal wells are not
anticipated in the next 10 years or the life of this Plan. However, as noted above in Section 1.5.1, the City
of Prior Lake put Wells 8 and 9 into operation as this Plan was being prepared. Well 8 is open to the
Jordan Sandstone aquifer and well 9 is open to the FIG aquifer. It is also anticipated that the City will
construct additional municipal wells in the next 10 years or the life of this Plan in order to meet future
water demand. Operation of these new wells may change the boundaries of the DWSMA in which the
wells operate or require the delineation of new DWSMAs. These minor changes to the physical
environment will likely not affect the management strategies for the Prior Lake DWSMAs presented
in this Plan.
The City of Prior Lake plans to work with the Boards of Supervisors for Credit River and Spring
Lake Townships to manage the portion of the eastern DWSMA that falls within these townships.
2.1.2 Land Use
Development within the City of Prior Lake is continuing. A current land use map and a projected
Prior Lake land use map for the year 2030 are shown on Figures 5 and 15, respectively. Inspection
of Figure 5 shows that current land uses in the portions of Credit River Township and Spring Lake
Township within the eastern DWSMA are consistent with current land uses within the City limits.
Projected land use in 2030 is to be consistent with Prior Lake's current growth planning.
Comparison of the current land use with the projected year 2030 land use (Figure 16) indicates that,
in general, the undeveloped properties (including currently vacant properties and properties currently
used for agriculture) within the DWSMAs will be developed. Future uses of these properties will
include residential and general industrial land uses. All of these future land uses are currently
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present within the DWSMAs. Thus, all land uses anticipated during the next 10 years or the life of
this Plan within the DWSMAs are currently present in the areas covered by this Plan. As a result,
adjustments in the land use within the DWSMAs such as those projected for the year 2030 will be
adequately addressed by the management strategies put forth in this Plan.
2.1.3 Surface Water
As discussed above, there are surface water bodies that meet the definition of public waters in the
Minnesota Statutes and wetlands within the DWSMAs. Prior Lake has in place plans (see Prior
Lake, 2005a and 2005b), ordinances, and zoning to protect these surface water bodies and wetlands.
Prior Lake's management of surface water bodies and wetlands is not expected to adversely affect
the management strategies for the Prior Lake DWSMAs. Rather, the City's management of surface
water bodies and wetlands should be viewed as a complement to the management strategies presented
in this Plan.
2.1.4 Groundwater
As the population of Prior Lake grows water demand in the City will grow as well. As discussed
in the City's 2030 Comprehensive Plan, additional municipal wells will be installed as needed to
meet the City's growing water demands. As noted in the 2030 Comprehensive Plan, it is anticipated
that most, ifnot all, of these wells will be installed in the western part of the City. The Jordan
Sandstone and other aquifers are being considered for these future wells.
City staff inspect the municipal wells daily and record the water volume pumped into the distribution
system. The MDH inspects all the municipal supply wells annually. This inspection includes
sampling of all wells to ensure they comply with applicable regulatory standards. In addition, Prior
Lake has a SCADA system that continuously measures the flow rate of water pumped from a well
and the water level (static or pumping) in the well and records the data hourly. The SCADA system
currently records water level data for wells 3, 6, and 7 and records flow rates for wells 3, 4, 5, 6,
and 7. The SCADA system can produce daily reports summarizing the data recorded for each of the
municipal wells. Based on the water level data collected by Prior Lake, the static levels in the source
water aquifers appear to fluctuate somewhat over time but there does not appear to be a general trend
toward decreasing static water levels.
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Prior Lake city ordinances related to groundwater use include ordinances covering required
connection to the municipal water system, repair of leaking water lines, requesting approval for well
installation, and outdoor water use.
In the next 10 years, it is possible that new business or industrial developments in Prior Lake may
seek to construct privately owned high-capacity wells completed in the Jordan Sandstone aquifer.
Such wells could potentially affect the DWSMAs, depending on their location. Prior Lake will work
with Credit River and Spring Lake Townships, to the extent possible, to restrict the installation of
new water supply wells in the main source water aquifer within the portions of the eastern DWSMA
that extend into each of these townships. The City of Prior Lake currently does not know of any
proposed developments that include plans for privately owned high-capacity wells within the
DWSMAs.
Beyond the addition of new Prior Lake municipal wells, no significant changes regarding
groundwater use within the DWSMAs or that could affect the existing DWSMA boundaries are
anticipated to occur within the next 10 years or the life of this Plan.
2.2 Impact of Changes
2.2.1 Water Use
Prior Lake's Water Emergency and Conservation Plan (Prior Lake, 2006a) projects annual water
demand will be 982.2 million gallons in 2015. Based on the information in the City's Water
Emergency and Conservation Plan and water use reported to the MDNR in 2005, water use is
expected to increase approximately 39% between 2005 and 2015. As discussed in Section 1.3.2
above, Prior Lake was in the process of requesting an increase in the City's groundwater
appropriation as this Plan was being prepared.
As discussed above, the City of Prior Lake has a water conservation program consisting of odd/even
outdoor water use restrictions.
To meet increasing water demand, Prior Lake plans to install additional wells in the future. It is
anticipated that the majority of the new wells will be installed in the western portion of the city. The
2030 Comprehensive Plan anticipates that these new wells may be installed in the Jordan Sandstone
aquifer or another aquifer. As these additional wells go into service, the City will review and update
their WHP As and DWSMAs as required by the Minnesota Wellhead Protection Rules.
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The placement of an additional high capacity well in or near the DWSMAs, or significant changes in
current groundwater appropriations by existing wells, could have an important impact on the aquifer
and local water supplies. These issues could also change boundaries of the delineated WHP As and
DWSMAs for the existing City of Prior Lake wells or change the static water levels in the City's
wells. The City of Prior Lake will work with the MDH Sourcewater Protection Unit to identify any
proposed high-capacity wells that may adversely affect the City's DWSMAs or source water aquifers
and provide interaction with the proposed well owner(s) to minimize problems.
2.2.2 Influence of Existing Water and Land Government Programs and
Regulations
Prior Lake's city ordinances related to the public water supply address connection to the municipal
water system, repair of leaking water lines, and outdoor water use. The following bullets summarize
these ordinances:
· Property owners or occupants are required to repair leaking water lines within 24 hours of
receiving oral or written notice of the presence of a leak.
· Property owners are required to connect to the municipal water system within one year of
the time that the system becomes available to their property.
· Outdoor water usage is regulated in Prior Lake on an odd/even basis. That is, outdoor
water usage is allowed at even-numbered addresses on even-numbered days and odd.
numbered addresses on odd-numbered days with no outdoor water usage allowed from 11
a.m. to 5 p.m. This system is in effect from May I through September 1. Watering of
new landscaping and plantings can be exempted from these outdoor water usage rules
exist if a written request is submitted to the City and subsequently approved. The City
Manager has the authority to declare a water emergency that would prohibit any outdoor
water use if certain conditions that threaten the City's ability to meet water demand are
present.
These ordinances have minimized water usage during peak demand times and reduced the overall
demand for public water supplies in the City.
Section 705.300 of the Prior Lake City Code requires that properties within the City must connect to
the municipal sewer system, if available. The City Code does not regulate ISTS on any properties
within the City that cannot comply with the requirements of Section 705.300. For any such
properties and for properties within the eastern DWSMA outside the City limits, the City relies upon
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Scott County Individual/Community Sewage Treatment Ordinance No.4 and Minnesota Rules
chapter 7080.
County and City ordinances, the MDNR Waters appropriations permitting program, and the State of
Minnesota Well Management and Drinking Water Supply Programs, Scott County's onsite sewage
treatment system ordinances, Scott County's and the MPCA's regulation of hazardous waste
generators, the MPCA's regulation of onsite sewage treatment systems, and the MPCA's oversight of
contaminant release response will be relied upon for assistance in regulating the installation of new
wells, water appropriation permitting, the proper sealing of unused wells, and regulation of potential
contaminant sources that could potentially affect drinking water quality in the City. The MPCA also
has a program in place for issuing permits for, and regulating operation of, storage tanks. The City
of Prior Lake believes that the current level of regulations and oversight are adequate to address
these issues.
Land use control and land development activities outside of the City of Prior Lake will be governed
by the local unit of government with jurisdiction in a particular area. This Plan has been developed
to protect the interests of the City of Prior Lake and, to the extent practicable, to have no adverse
affect on the plans and strategies developed for adjacent jurisdictions. Prior Lake's eastern DWSMA
extends into Credit River and Spring Lake Townships. This Plan will be provided to these townships
as a resource for future land development planning. Township ordinances and plans related to land
use will be relied upon for the management of the portion of Prior Lake's eastern DWSMA that
extends into these townships. The Wellhead Protection Manager will, to the extent feasible and
practicable, communicate the goals and objectives of this Plan to the Credit River and Spring Lake
Townships Boards of Supervisors.
The City of Prior Lake will continue to rely on State, County, and local agencies and regulations to
handle issues outside of the City's boundaries regarding water conservation, water appropriations,
well drilling, septic systems, sanitary sewer extensions, and stormwater management. The City will
comply, as necessary, with the requirements of the MPCA's current Stormwater Pollution Prevention
Program (SWPPP) and the National Pollutant Discharge Elimination System (NPDES) Phase Two
program to regulate the quality and quantity of stormwater discharge. Staff will look for the MDH to
continue to regulate the installation of wells and proper sealing of unused wells.
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It should be noted that during the development of this Plan Scott County staff indicated that the Scott
County program to provide grants to well owners to cover a portion of the cost of sealing unused
wells is currently without adequate funding and, as a result, is not active.
These programs have proven to be effective. City staff will cooperate with these agencies as issues
anse.
2.2.3 Administrative, Technical, and Financial Considerations
Prior Lake will have adequate resources available to regulate the public water supply's source water.
Funds to support ongoing wellhead and source water protection efforts will come from the City's
utilities budget. Wellhead and source water protection activities will be evaluated on an annual
basis, and any changes in the focus of the tasks will also be evaluated to determine if additional
funding will be necessary to accommodate the changes.
For this Plan to be effective, the City will need to raise public awareness of the issues affecting its
public water supply through public educational programs. Therefore, the majority of wellhead and
source water protection actions will include public education. Routine administrative duties will be
directed or performed by the Wellhead Protection Manager. Specific tasks and strategies will be
performed by the Wellhead Protection Manager or delegated by the Manager to City staff or outside
resources.
Increasing water demand resulting from an increasing population will make it necessary for the City
to expand its public water supply system in the future. City staff continue to evaluate the water
distribution system as the community grows. In addition to constructing additional municipal wells,
additional storage reservoirs, water treatment facilities, and an expanded water distribution system
will likely be needed as well.
The installation of additional municipal wells in the next 10 years will likely affect the size and shape
of Prior Lake's WHPAs and DWSMAs or require the delineation of new WHPAs and DWSMAs.
The City intends to amend and update its Wellhead Protection Plan to incorporate new wells as
required by the Wellhead Protection Rules.
Prior Lake will work, to the extent practicable, with Credit River and Spring Lake Townships to
manage the portion of the eastern DWSMA that extends into these Townships. In addition, the City
intends to work in conjunction with Scott County and neighboring communities to protect the source
water resources as much as possible when it is beneficial and logistically feasible.
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