HomeMy WebLinkAboutCity Council Packet 05-05-2015 SpecialCITY OF PLYMOUTH
AGENDA
SPECIAL COUNCILMEETING
MAY 51 2015, 5:30 p.m.
PARKERS LAKE AND MEDICINE LAKE CONFERENCE ROOMS
1. CALL TO ORDER
2. TOPICS
5:30 p.m. HRA Interviews (Parkers Lake Conf. Room)
6:00 p.m. Medicine Lake Water Level Study (Medicine Lake Conf. Room)
3. ADJOURN
Special Council Meeting 1 of 1 May 5, 2015
Agenda
ribCity of Number:
Plymouth
To: City CouncilAddingQualitytoLife
SPECIAL From: Derek Asche, Water Resources Manager
COUNCIL MEETING
Date: April 27, 2015
May 5, 2015
Item: Medicine Lake Water Level Study
Since 2009, there has been recurring concerns brought to the Bassett Creek Watershed
Management Commission (Commission) by the City of Medicine Lake and the Association of
Medicine Lake Area Citizens (AMLAC) regarding recreational impacts on Medicine Lake from late
season water levels dropping too low for recreational activities. The City of Plymouth (via the
Water Resources Fund) funds approximately 45% of the Commission resources (engineering,
administration, legal, etc...) dedicated to responding to such concerns via annual assessments
directed at the operating costs of the watershed.
The Bassett Creek Watershed has had an extensive and complex history of flooding and water
management. Pre -1970 flooding in the Bassett Creek Watershed resulted in the Army Corps of
Engineers (Corps) completing a study of flooding problems within the watershed. An outcome
of this study was a plan to replace the Medicine Lake Outlet in 1996 as a cooperative project
between the City of Plymouth, the Minnesota Department of Natural Resources (DNR), the
Bassett Creek Watershed, and Hennepin County. Two issues were cited by City staff regarding
the need to replace the previous Medicine Lake Outlet:
1. Water seepage during periods of low rainfall allowed the lake level to drop below the
outlet level.
2. Development upstream of Medicine Lake discharges additional water into the lake and a
new outlet is needed to minimize lake "bounce" after rain events.
Water level data from the 1970s to the mid-1990s from the DNR indicated that water levels were
generally increasing (Figure 1) which supports staff's conclusion that additional water was
discharging to Medicine Lake. Initially, the Corps indicated there was potential for an adjustable
or variable outlet structure which could lower water levels up to 2.5 feet to provide additional
storage in the lake and to prevent flooding. Further analysis concluded an adjustable or variable
outlet structure was not practical at this location and therefore, a fixed outlet structure was
designed to reduce or eliminate seepage and mitigate the lake "bounce" after rain events to
reduce flooding. Water level data from 1996 through 2014 indicate the current outlet structure
appears to mitigate lake "bounce". Additionally, Medicine Lake appears to be dependent upon
precipitation to maintain water levels based on the correlation of precipitation (both snow and
rain) to lake level (Figure 2).
Low water levels can impact swimming and boating, among other activities, and the Commission
responded with several memos and reports intended to explain how the water levels in Medicine
Page 1
Lake function, however, this did not satisfy the concerns. In 2014, the Cities of Plymouth and
Medicine Lake began discussing the possibility of partnering 50-50 on funding a study to further
investigate water levels in Medicine Lake and what options, if any, could be completed to
improve recreational opportunities in July, August, and September. Subsequently, a request for
proposals (RFP) was developed cooperatively between our two Cities and submitted to three
consultants for consideration. By default, Plymouth Water Resources staff has been coordinating
the RFP and the selection process.
The RFP included seven options for investigation by the successful consultant pertaining to water
levels in July, August, and September. Those options included modification to the outlet of
Medicine Lake, modification of upstream structures draining to Medicine Lake, sprinkling and/or
water appropriation regulations, dredging, the effect of late season (July, Aug, Sept) evaporation,
the effect of water appropriations permits, and the effect of private wells.
The total cost of the Wenck Associates proposal is $45,012 (copy attached). The cost for this
study is not budgeted. A 50-50 partnership with the City of Medicine Lake to complete this study
would require a City of Plymouth contribution of $22,506. Although Water Resources staff has
been coordinating this effort, they feel that this study and resulting expenditure is not
appropriately funded from the Water Resources Fund since the lake level is a recreation issue.
The cost for the study is not budgeted in any city fund or budget.
Attachment: Medicine Lake Water Level Investigation Feasibility Study - Wenck
Page 2
Page 3
Medicine Lake Water Elevation 1973 - 2014
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Normal Wate Level: 887.7 water Level
100 year High ater Level: 890.0 (890.55) Elevation
Highest recorded: 890.68 ft (07/15/1951)
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Wencl<
November 7, 2014
Mr. Derek Asche
Water Resources Manager
City of Plymouth
3400 Plymouth Boulevard
Plymouth, MN 55447
Wenck Associates, Inc.
1800 Pioneer Creek Ctr.
P.O. Box 249
Maple Plain, MN 55359-0249
763) 479-4200
Fax (763) 479-4242
E-mail: wenckmp@wenck.com
Re: Request for Scope of Services, Medicine lake Water Level Investigation;
Dear Mr. Asche:
Thank you for the opportunity to submit the enclosed Scope of Services to investigate options to
improve enjoyment of Medicine Lake during the months of July, August, and September with an
emphasis on aquatic recreation. Wenck understands there are many dynamics associated with the
enjoyment of Medicine Lake as a recreational resource for the City and residents. Wenck has
assembled a team of professionals with key experience to provide superior service and results to
the City.
Wenck values the relationship it has established with the City of Plymouth as its partner on
several projects related to water resources restoration and water quality improvements including
the Elm Creek restoration, Wood Creek channel stabilization, Plymouth Creek Pond design,
Plymouth Creek restoration, and wetland monitoring.
We are eager to continue our relationship by assisting with this investigation, and we believe we
are the best choice for this project for several reasons:
An experienced team with watershed -level evaluation at the core of our practice. The Wenck
staff committed to this project has over 50 years of experience leading watershed, stream and
lake restoration and is versed in a multitude of techniques for water quantity and quality
management. This team provides a multifaceted approach to watershed investigation and
analysis.
Lake and outlet modeling design and construction
The Wenck team has completed over 20 lake and reservoir water level feasibility studies to
maximize a combination of recreational, water quality, water supply and flood control benefits.
Four of the most interesting feasibility studies in the metro area have been on School Section
Lake in the Browns Creek Watershed, Prior Lake, Mooney Lake and Lake Pulaski. These lakes
are similar because they have limited capacity outlets, a high potential for shore and structure
flooding and are highly used for water recreation. The analyses were done using recent periods
of precipitation and evaporation to simulate the existing structure and proposed options. The
TM 756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\02 Cover Letter.docx
Page 6
Mr. Derek Asche
City of Plymouth
Proposal for Medicine Lake Water Level Investigation
Page 3 of 10
Prior Lake outlet resulted in construction of a labyrinth weir to allow a maximum discharge at
low head with a minimal structure footprint.
A history of developing cost effective feasibility studies that result in focused and cost effective
solutions. Wenck has worked with many clients on several feasibility studies, specifically with
the City on the Four Seasons Mall Water Quality Improvement and Elm Creek Stream
Restoration feasibility studies. As District Engineer for municipalities, counties and watershed
districts, we have a unique perspective and longtime experience that streamlines our evaluation
of proposed options and considers the long term impacts to local residents and landowners.
A proven ability to deliver high-quality projects for a reasonable budget. In our past projects
with the City, Wenck has worked hard to deliver quality products at reasonable prices for the
agreed upon scope of work. Wenck has a long history of delivering projects on-time and on
budget. We know that the timeline is critical for this project and we will meet the City's
timeline.
Wenck proposes an additional Option H to investigate the feasibility of a lake level optimization
model for Medicine Lake. Investigating the lake level optimization model would include the
feasibility of incorporating real-time precipitation forecasting data from NOAA to provide risk
assessment for flooding concerns versus recreational use.
We look forward to discussing these qualifications with you further. Our scope, budget and
timeline are presented on the following pages. If you have any questions, or if you wish to
arrange an interview, please contact me at your convenience.
On behalf of the 200 -plus employee -owners of Wenck Associates, thank you again for this
opportunity. If you have any questions or need further information, please feel free to contact me
at (763) 479-4208 or ematthiesengwenck.com.
Sincerely,
WENCK ASSOCIATES, INC.
Ed Matthiesen, PE, Principal
Page 7
Project Personnel
Wenck Associates has assembled a team with experience in watershed assessment for hydrologic
and hydraulic modeling. Brief biographies for each team member are presented below. Full
resumes are available at your request.
Ed Matthiesen, PE, Principal — Project Manager and Water Resources
Engineer
Mr. Matthiesen will serve as the senior water resources engineer. Mr.
Matthiesen has 30 years of extensive experience in water resources and
environmental engineering. His water resources experience includes being
the District Engineer for three Twin Cities area watershed districts and
four Joint Powers Associations, writing municipal comprehensive
stormwater plans, outlet structure and storm sewer design, conducting
evaporation studies, aquifer analysis, water quality protection plans, and
developing computer hydrologic and hydraulic models. He was nominated
by the Minnesota Chapter of the American Public Works Association for
the national 2011 Water Resources Professional of the Year award by
APWA.
Joel Toso, PhD, PH, PE, Principal — Water Resources Engineer
Mr. Toso will be a technical resource for the project. He has more than 28
years of experience with water resources engineering and has served as an
instructor of applied hydrology and hydraulics at the University of
Minnesota for more than 18 years. He is a professional hydrologist and
professional engineer. A specific area of expertise is hydrologic analyses
including water balance computations for lakes and reservoirs. Selected
directly applicable projects include: 1) expertise witness provided for a
legal case involving 20 years of historic lake level modeling, 2) hydrologic
design of an 18 -square -mile reservoir for the South Florida Water
Management District, and 3) hydrologic investigations to determine
alternatives for relieving high Devils Lake levels.
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\03 Personnel.docx
Wenck
Engineers • Scientists
Business Professionals
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Kirby Templin, EIT — Water Resources Engineer
Mr. Templin has 3 years of experience in the fields of water resources and
civil engineering. Mr. Templin graduated from the University of
Minnesota -Twin Cities in 2011 with an MS in Civil Engineering with an
emphasis in water resources engineering. Mr. Templin also received a
certificate of stream restoration science and engineering from the
University of Minnesota -Twin Cities in 2011. His project and technical
experience includes: hydrologic and hydraulic modeling, water quality
modeling, field data collection and processing, and geographic
information systems (GIS) Services. Mr. Templin has experience using
HydroCAD, XPSWMM, P8 Urban Catchment Model, Pondnet, HEC -
RAS, ArcMap (GIS) and AutoCAD. Mr. Templin also has field
experience with surveying, BMP inspections, and construction
observation.
Eileen Weigel, EIT — Water resources Engineer
Ms. Weigel has three years of experience in the fields of water resources
and environmental engineering. Ms. Weigel graduated from the
University of Minnesota -Twin Cities in 2010 with an MS in Geological
Engineering with an emphasis in water resources. Ms. Weigel also
received a certificate of stream restoration from the University of
Minnesota -Twin Cities in 2010. Her project and technical experience
includes: hydraulic modeling, groundwater and surface water quality
modeling and analysis, stream and lake restoration, soil and groundwater
remediation, field data collection and processing, and geographic
information systems (GIS) Services. Ms. Weigel has experience using the
P8 Urban Catchment Model, HydroCAD, HEC -RAS, XP-SWMM,
ArcMap (GIS), Pondnet and BATHTUB. Ms. Weigel also has field
experience with surveying, BMP inspections, and construction oversight.
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\03 Personnel.docx
Wenck
Engineers • Scientists
Business Professionals
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Project Understanding and Approach
It is our understanding that the City of Plymouth and Medicine Lake is interested in developing a
feasibility study to retain water and improve the quality of recreational opportunities in Medicine
Lake during July, August, and September of each year. The goal of the feasibility study is to
evaluate options to improve enjoyment and aquatic recreation during the months of July, August,
and September by maintaining sufficient water levels.
APPROACH
Wenck's approach to developing feasibility studies includes partnering and close communication
with the City to obtain all available information and historical knowledge to fully investigate and
evaluate the project options. This approach is highly effective while minimizing cost and assures
that all possible project options have been evaluated thoroughly. Wenck will conduct the
following scope of services during the development of the Feasibility Study:
SCOPE OF SERVICES
Option A. Modification to the Outlet of Medicine Lake
A modification to the outlet of Medicine Lake will be investigated by first obtaining as -built
information for the existing outlet, quantifying lake discharge with available lake level
monitoring data and then compare the lake discharge results with the results from the XPSWMM
model. The outcome of the first step is to validate the relationship between the model and
existing conditions, and how groundwater and evaporation losses are represented through model
results. After validation of the model, modifications to the outlet can be investigated with the
focus to maintain lake water levels during the months of July, August, and September. Lake level
data and precipitation data will be reviewed to identify target drought year conditions and wet
year conditions to evaluate the performance of proposed outlet modifications. The model will
also be run with the Atlas 14 100 -year precipitation event and 10 day snowmelt event to verify
the regulatory floodplain.
The report evaluation of option A will include the following:
Description of the Outlet Modification and Outcomes Pertaining to Lake Water Levels
Schematic Which Depicts the Proposed Outlet Modification
Cost Estimate for Outlet Modification and Annual Operations and Maintenance
Permitting Requirements
Comparison to Other Options
Discussion for Implementation
Option B. Modification of Upstream Structures Draining to Medicine Lake
Modifications to upstream structures and stormwater systems will be investigated in a similar
approach to the modification of Medicine Lake to maximize water yield, protect biological
needs, and no increase in flood elevations. The initial steps will include obtaining and reviewing
available information which includes storm sewer information, as -built information, water
surface elevation monitoring data and validation of the XPSWMM model. Opportunities for
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\04 Approach.docx
Wenck
Engineers • Scientists
Busineph4sic als
upstream modifications will be first identified within the watershed and second investigated to
understand the outcomes on maintaining lake levels in the months of July, August, and
September. Opportunities that will be investigated include the potential for increased storage
which can be released to Medicine Lake when needed, and opportunities for the diversion of
stormwater from new sources which can be limited to the months of July, August, and
September. The performance of upstream modifications will be evaluated for the target drought
and wet year conditions.
The evaluation of option B will include the following:
Description of Upstream Modifications and Outcomes Pertaining to Lake Water Levels
Figures Which Detail Upstream Modification Alternatives
Cost Estimate of Alternatives for Upstream Stormwater System Modifications
Permitting Requirements
Comparison to Other Options
Discussion for Implementation
Option C. Sprinkling and/or Water Appropriation Regulations
The study on the impact of sprinkling and/or water appropriation regulations on lake levels will
involve reviewing existing regulations, and available data and knowledge of irrigation and water
appropriation usage to estimate the impact on lake levels during the months of July, August, and
September. If information is not available on water appropriation, a worst case scenario that is
within reason can be developed to understand the extreme appropriation impacts on the lake
levels.
The evaluation of option C will include the following:
Description of Existing Sprinkling and/or Water Appropriation Regulations
Discussion of Water Appropriation Impacts
Cost Estimate of Water Appropriation Regulations for Review and Enforcement
Permitting Requirements
Comparison to Other Options
Discussion for Implementation
Option D. Dredging
Dredging opportunities will be evaluated throughout the lake with focus on aquatic recreation
during the months of July, August, and September. Dredging specific areas is an option that may
improve some aquatic activities in general and as lake water levels decrease. Dredging options
will be reviewed on the independent benefit and also the benefits in addition to other water level
management practices that are investigated. Dredging will not be a solution to improve all
aquatic activities but may be able to provide improved enjoyment for targeted activities.
The evaluation of option D will include the following:
Description of Dredging Project Options and The Recreational Impacts
Figures Which Detail Dredging Project Options
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\04 Approach.docx
Wenck
Engineers • Scientists
Businepgw gsloraIs
Cost Estimate for Dredging Projects
Permitting Requirements
Comparison to Other Options
Discussion for Implementation
Discussion for Soil Sampling and/or Boring Compliance Requirements
Option E. Effect of Late Season (July, August, September) Evaporation on Water Levels
in Medicine Lake
Evaporation at Medicine Lake will be analyzed by computational methods to estimate water
losses during the months of July, August, and September. Water loses at Medicine Lake are
likely primarily evaporation and groundwater, and also from lesser known impacts from water
appropriation and other possible sinks. Multiple methods will be used to aid in quantifying water
loses due to evaporation versus other loses such a groundwater, etc. Estimated groundwater
levels from the metro area groundwater model will be evaluated for the Medicine Lake area to
better understand the impacts of groundwater as it relates to the evaporation estimates. Previous
data and studies on evaporation at Medicine Lake will also be reviewed if it is available.
The evaluation of option E will include the following:
Description Quantifying Evaporation and Detailing the Methodologies Used to Estimate
the Evaporation
Cost Estimate, if Any, As it Relates to Evaporation
Permitting Requirements, if Any, As it Relates to Evaporation
Comparison to Other Options, if Any, As it Relates to Evaporation
Discussion on Influence of Evaporation as it Relates to Aquatic Recreation
Option F. Effect of Water Appropriations Permits on Water Levels in Medicine Lake
Option F will build on the review and understanding of existing water appropriation regulation as
detailed by Option C. Increased regulation will be discussed and the ultimate estimated effect on
water levels for the months of July, August, and September will be evaluated.
The evaluation of option F will include the following:
Description of Increased Appropriation Regulation and Effect on Water Levels
Cost Estimate, As it Relates to Increased Regulation
Permitting Requirements, As it Relates to Increased Regulation
Comparison to Other Options
Discussion for Implementation
Option G. Effect of Private Wells on Water Levels in Medicine Lake
The locations and quantity of private wells within the Medicine Lake watershed will be reviewed
along with any available data to aid in understanding the effect of the private wells on lake
levels. If well usage data is unavailable, worst case scenarios can be established to quantify
potential impacts of the private wells. A worst case can assume all water usage directly
influences the lake water level. The lake level decrease due to private wells can be simply
Wenck
Engineers • Scientists
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\04 Approach.docx Businep9 g4ss)tzals
evaluated as the well usage volume estimate over the surface area of the lake. The magnitude of
the estimated decrease can be compared to other sources of water losses, such as evaporation, to
determine the overall impact and influence the private wells may have on the water levels of
Medicine Lake.
The evaluation of option F will include the following:
Description of Private Well Usage and Potential Influence and Impact of Medicine lake
Cost Estimate, If Any, As it Relates to Private Wells
Permitting Requirements, As it Relates to Private Wells
Comparison to Other Options
Discussion for Implementation
Option H. Other options as it applies to stated goal
As an optional task, we propose to investigate the feasibility of building a lake outlet operation
probabilistic model to optimize lake levels using NOAA precipitation forecasting data specific to
Medicine Lake as shown below. From a phone conversation with State Climatologist Pete
Boulay, there appears to be sufficient forecasting accuracy and data precision within the
Medicine Lake watershed within 48 hours to manage lake levels within a risk tolerance for
flooding concerns versus recreational use. Figure 1 is an example of available forecasting data
from NOAA which may be useful in developing a real-time risk probabilistic model to optimize
Medicine Lake water levels.
1. Example of precipitation forecasttnz data from NUAA specific to Medicine Lake Area
Nva 5 2314
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Odin Rein:3.16in RainA.08in I Rain:0.31in
lam 1h Tam bairn lP_ 4pm TPM 1O 1a 4am Tam 10am fpm 4p -
The evaluation of option H will include the following:
Description of the Probabilistic Model to Optimize Lake Levels
Cost Estimate for Implementation of the Probabilistic Model and Annual Operations
and Maintenance
Permitting Requirements
Comparison to Other Options
Discussion for Implementation
T:\1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\04 Approach.docx
Wenck
Engineers • Scientists
Businepgw gslorls
Cost Estimate and Timeline
Table 1 outlines Wenck's proposed costs to complete the Medicine Lake Water Level
Investigation Feasibility Study. All work will be completed on a time and materials basis not to
exceed a project total of $45,012.
Table 1. Proposed cost estimate for completing the Medicine Lake Water Level Investigation Feasibility
Studv.
Task Description Total
A Modification to the outlet of Medicine Lake 8,405
B Modification of upstream structures draining to Medicine Lake 6,702
C Sprinkling and/or water appropriation revulations 4,066
D Dredging 5,728
E Effect of late season (July, Aug, Sept) evaporation on water levels in Medicine Lake 5,598
F Effect of water appropriations permits on water levels in Medicine Lake 4,215
G Effect of private wells on water levels in Medicine Lake 4,577
H Other options as it applies to stated goal 5,723
TOTAL 45,012
Hourly rates for specific professional services are as follows:
Professional I: Kirby Templin, E.I.T.
Professional L• Eileen Weigel, E.I.T.
Professional IV: Ed Matthiesen, P.E, and Joel Toso, P.E. $190.00
Table 2 outlines our proposed timeline for completing the Medicine Lake Water Level
Investigation Feasibility Study.
Table 2. Proposed timeline for completing the Medicine Lake Water level Investigation Feasibility
Study.
Task Completion Date
Draft Feasibility Report January 21, 2015
Final Feasibility Report January 30, 2015
TA1756 Plymouth\00\P-0003 Medicine Lake Water Level Investigation\05 Costs and Schedule.docx
Wenck
Engineers • Scientists
Busi'Psas Pgefe sipnais
City of Plymouth
City Council Study Session
Medicine Lake Water Level Investigation
May 5, 2015
Derek Asche, Water Resources Manager
Medicine Lake
Second largest lake in Hennepin County by acreage
Stakeholders include:
The United States Army Corps of Engineers
The Minnesota Department of Natural Resources
Hennepin County
Bassett Creek Watershed
Three Rivers Park District
Cities of Plymouth and Medicine Lake
Lakeshore owners and area residents
252 total lakeshore properties (131 in Plymouth, 121 in Medicine
Lake)
Medicine Lake Water Level Investigation
Complaints of low water levels during July, August, and September
which can impact recreation on the lake
This proposal is to investigate the potential to maintain water levels in
Medicine Lake in July, August, and September closer to the current
run -out elevation
Portions of Medicine Lake riparian area are shallow amplifying the
problem.
Consideration of DNR requirements to modify run -out elevations
This investigation may or may not return viable options and there is
no guarantee any improvements or changes within the watershed will
be made.
Medicine Lake Water Level Investigation
This proposal was developed by the Cities of Plymouth and Medicine
Lake and would investigate options to improve recreational
opportunities on Medicine Lake in July, August, and September.
Options included for investigation are:
Medicine Lake outlet modification • Dredging
Modification of upstream structures • Effect of private well use
Sprinkling/water appropriation • Effect of late season (July, Aug, Sept)
review evaporation
Water Level History
Flooding in Bassett Creek Watershed prior to 1970
United States Army Corps of Engineers (USACOE)
Study on flooding within the Bassett Creek Watershed
A portion of the investigation included Medicine Lake Outlet
Water Level History
Flooding in Bassett Creek Watershed prior to 1970
United States Army Corps of Engineers (USACCIE)
Study on flooding within the Bassett Creek Watershed
A portion of the investigation included Medicine Lake Outlet
The Medicine Lake Outlet was replaced in 1996
Fixed Weir
Reduce or eliminate seepage through the existing dam
Minimize flooding after heavy rain events
Variable/Adjustable Weir Option
USACOE reviewed a variable/adjustable outlet control option in
concert with the fixed weir option in 1995
A variable/adjustable option would provide for stoplogs or gates which could
draw the lake level down 2.5 feet from the run -out elevation to accommodate
for heavy rains or spring snow melt.
An operation plan and flood warning system was also recommended.
Further review by the USACOE indicated an adjustable weir and operation
plan was not practical at this location.
Lake Minnetonka, Prior Lake, and Lake Nokomis have adjustable outlets
Variable/Adjustable Weir Option
Lake Nokomis adjustable weir
Lake Nokomis weir cited as a comparable to the request for Medicine Lake
Aquatic invasive species prevention by preventing Minnehaha Creek from
back -flowing into Lake Nokomis
Continuously below run -out elevation for 9 years
Downward trend in water levels
Minneapolis Park and Recreation Board is the only property owner involved
No existing flooding issues
Project cost $107,000 in 2012 and replaced an existing adjustable weir
installed in 2001
Existing flooding concerns
Medicine Lake Water Level 889.5
Medicine Lake Outlet — April 30, 2014
e i br
i or x_..
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s
2840-2870 Evergreen — April 30, 2014
Existing flooding concerns
Medicine Lake Water Level 889.03
Medicine Lake Outlet — June 20, 2013 2840 Evergreen Lane — June 20, 2013
Existing flooding concerns
Medicine Lake Water Level 889.03
City of Medicine Lake — June 20, 2013
227 Peninsula Road
Topographic — City of Medicine Lake
Funding
The cost of the Medicine Lake Water Level Investigation is $45,012
The cost is currently proposed to be split 50-50 between the Cities of
Plymouth and Medicine Lake
Cost to each municipality is $22,506
The City of Medicine Lake has approved funding
This is not identified in either the 2015 Recreation or Water
Resources Budget
Options
Fund and complete the investigation as a cost share between the
Cities of Plymouth and Medicine Lake
Request the Bassett Creek Watershed complete the study. This
proposed investigation is different than previous requests to the
watershed.
Take no action on the investigation
kalD
eers
llM
PERMIT REQUIREMENTS TO
CHANGE RUNOUT ELEVATIONS
The following steps are not all-inclusive
but do list essential permit application
requirements, under Minnesota Statutes
I 03G, for changing the runout elevation
of a dam.
Permit Application. A permit applica-
tion must be signed by a majority of
riparian owners requesting a permanent
change in runout elevation.
Flowage Easements. Purchase or
donation of flowage easements and
consent from all owners of riparian land
abutting the lake, as well as any con-
nected waters that would also be af-
fected, are required.
Environmental Assessment. An envi-
ronmental assessment must be prepared
that documents impacts on wetland
habitat, fish spawning areas, waterfowl
and songbird nesting areas, as well as
strategies to address shore erosion due to
wave action and winter ice push.
Engineering. Engineering plans must be
prepared that show the proposed physical
changes to the dam.
Hydrology/Hydraulics. A hydrologic/
hydraulic analysis must identify antici-
pated changes in lake levels and stream
flows.
Surveys. Surveys must be prepared that
show all shoreland and existing develop-
ment that would be affected by the
proposed change. These surveys must
identify compliance with shoreland
ordinance standards for both the existing
and proposed runout in terms of lot size,
structure and sewer system setback, and
structure and sewer system elevations
above the highest proposed water eleva-
tion.
Outlet Dant Maintenance
DNR Waters owns and maintains more than 304 lake outlet darns in Minne-
sota. The primary goals for dam maintenance are to protect existing
shoreland owners' rights and downstream owners' rights to water available
within natural precipitation variations.
Maintenance involves ensuring that each dam is safe and functional,
operates at the authorized runout elevation, and provides free-flowing_
conditions. Inspections of dams are conducted to ensure that the stop logs
are at the authorized setting, to repair or replace damaged or worn equip-
ment, and to remove obstructions as necessary.
Historical Operation of Outlet Dams
Most lake outlet dams, which were built in the 1930s to conserve water,
generally feature several 5 -foot -wide openings, called bays, with provisions
to add and remove wooden stop logs. The runout level of a dam depended
on the number of stop logs placed in each bay. Stop logs were managed by
local observer/operators at each lake for 1 a-12 years after the dams were
built. When precipitation suddenly (and unpredictably) returned to normal
and above normal, flooding occurred around many lakes resulting in claims
for damages by lakeshore property owners. It became apparent that stop log
operation by local observers could not maintain uniform lake levels.
Thereafter, department engineers inspected each dam, examined the shore
of the affected lake, and analyzed all water level records and other avail-
able information about each lake. A decision was then made to set an
authorized stop log level for each dam. The goal was to sett the stop logs at
an elevation that would retain as much water as possible yet eliminate
complaints of high water and the associated claims of damage from flood-
ing. The authorized stop log setting is maintained by DNR Waters as the
legal runout elevation,
Outlet dam.
DNR maintenance specialist replacing wooden stop
logs with steel channels at the Island Lake outlet dam
in Crow Wing County (photograph by Ron and Judy
Rolfe).
Changing a Runout Elevation
It is the goal of DNR Waters to maintain existing flows and
water level conditions at lakes with outlet darns to the maxi-
mum feasible extent. However, shoreland owners on a lake
may have varied and differing opinions about "desirable" lake
water levels. Proposals to change water levels are difficult to
accomplish due to legal, environmental, and financial realties
see details in sidebar on page 1).
Potentially serious consequences may result from changing a
runout elevation, such as navigation problems, shore erosion,
water quality degradation, ice damage, and flooding. Chang-
ing a runout to solve a problem may create new problems that
are unacceptable to other owners or to future owners. Regard-
less of the runout elevation of a lake, water levels will fluctu-
ate because of variations in precipitation, which cannot be
controlled.
Legal Considerations
Unauthorized tampering with set runouts is an ongoing
problem at dams in Minnesota. According to Minnesota
Statutes Chapter 103G, it is unlawful to change the runout elevation of a dam without prior permit authorization from the
DNR. Persons found to be responsible for unauthorized changes to a dam are subject to criminal enforcement action.
Along with the criminal action is the potential of lawsuits brought by aggrieved shoreland owners for flooding, lack of
access, or downstream damages due to flow changes resulting from the illegal tampering.
The state cannot legally alter a stop log elevation in response to individual requests because of high or low water level
conditions. To raise a runout would cause water to cover land it did not previously cover, which may be a "taking" of land
without compensation. It is unconstitutional for government to take private property without due process. DNR Waters'
position and legal obligation is to maintain the authorized stop log setting and allow water levels to fluctuate in response
to precipitation that falls within a lake's watershed.
A formal permit process exists for those shoreland owners who may wish to pursue a permanent change in runout eleva-
tion (see sidebar, page 1). It must be clearly understood that no permit decision by the DNR is required until complete
information is provided by the applicant(s). Costs associated with design, engineering, flowage easements, and structural
improvements are the responsibility of the applicant(s), or a local governmental unit acting on behalf of the applicant(s).
072004 State of Minnesota, Department of Natural Resources. Prepared by DNR Waters.
DNR Contact Information
Mn+tesate DNR Waters website lists Area Hydrologists:
www. dnr. state.m m usfwaters
DNR Waters in St. Paul:
500 Lafayette Road
DNR Information Center
Twin Cities: (651) 296-6157
Minnesota toll free: 1-888-646-6367
Telecommunication device for the deaf (TDD): (651) 296-5484
TDI} toll free: 1-800.657-3929
PWrNW OF St. Paul, MN 55155-4032 This information is available in an alternative format on request.
wmes (651) 296-4800 Equal opportunity to participate in and benefit from programs of the Minne-
sota Department of Natural Resources is available regardless of race. color
national origin, sex. sexual orientation. marital status, status with regard to
public assistance. age. or disability. Discrimination inquiries should be sent
to Minnesota DNR. 500 Lafayette Road. St. Paul. MN 55155-403 1: or the
Equal Opportunity Office. Department of the Interior. WpI6 c,,214C 20240.
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