09/15/2005 - City Council Public Works Committee13
AGENDA
PUBLIC WORKS COMMITTEE MEETING
SEPTEMBER 15, 2005
5:15 P.M.
EAGAN CITY HALL
ENGINEERING CONF. ROOMS lA & All
L AGENDA ADOPTION
IL REVIEW LEBANON HILLS REGIONAL PARK STORM
WATER MANAGEMENT PLAN
III. OTHER BUSINESS
TV. ADJOURNMENT
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PUBLIC WORKS COMMITTEE MEETING
THURSDAY, SEPTEMBER 15, 2005
5:15 pm
LEBANON HILLS REGIONAL PARK STORM WATER MANAGEMENT PLAN
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City staff are aware of a 40 year history of drainage concerns with the Lebanon Hills Regional
Park (LHRP). The concerns primarily focus on the flooding of Cliff Road and Lakewood Hills
Road, a private street, which closes all access to the Lakewood Hills neighborhood. Additional.
concerns include the impact to individual septic system drain fields, loss of trees and the potential
for flooding of residences. Current city staff pressed the Dakota County Parks Department to
address the flooding concerns by addressing drainage within LHRP about 1985. At that time, the
County Board adopted a policy that all drainage within LHRP would be addressed within LHRP
without the use of a typical storm sewer system or connection to the City of Eagan's storm sewer
system. The City of Eagan had approved a Stormwater Management Plan in 1984 that had
included addressing the drainage within LHRP and continued to construct the storm sewer system
throughout the city accordingly.
During the late 1990s, County staff contracted a consultant to create a drainage management plan
that would function internally to LHRP. Prior to the County's acceptance of this plan, the July
2000 Storm was unleashed on Eagan and LHRP, resulting in the flooding of Cliff Road and
Lakewood Hills Road, as well as numerous other locations within the city. The County expended
about $1 million in an attempt to address the flooding, but was ordered by the Minnesota
Department of Natural Resources (DNR) to remove all flood mitigation efforts within the park
due to environmental impacts. The County expended an additional $1 million in the restoration
efforts directed by the DNR. In the past five years, three incidents, including the July 2000
Storm, have occurred requiring extensive pumping of drainage from LHRP in to the Eagan storm
sewer system in order to protect private property from the previous listed concerns.
County Parks staff has contracted with another consultant in the past few years to prepare a storm
water management plan that would properly address the drainage concerns within and
downstream of LHRP. With the direction to develop an ecologically appropriate plan to address
the storm water management problems of the past, the consultant has extended their analysis
beyond the limits of the park boundary.
With the recent frequency of drainage issues with LHRP, members of the Lakewood Hills
neighborhood have expressed their frustration with the lack of resolution to this long term
problem to both city and county officials. Recent development within the southeast corner of
Eagan, which drains in to LHRP, has heightened the concerns of the residents and increased the
City Council's awareness of the LHRP drainage issue. As a result, the Council conditioned the
approval of a portion of this development upon the approval of a storm sewer improvement to
address these drainage concerns.
On July 6, 2004, the City Council approved Project 905, Long Acre Outlet/Lebanon Hills
Regional Park Storm Drainage Improvements, consisting of the construction of storm sewer
improvements in southeast Eagan. The improvements will provide the managed delivery of
drainage from southeast Eagan (Long Acres development/Gun Club pond) into and through
LHRP by way of Marsh Lake and McDonough Lake to the public storm sewer system at Pond
LP -51 and the Holland Lake lift station. The project will address the drainage needs of LHRP's
drainage outlet in the area northwest of McDonough Lake, near Cliff Road. The approved project
includes all of the basic improvements detailed in the feasibility report and the following
upgraded improvements: Driveway Improvements adjacent to Pond LP -51, Marsh Lake Pipe
Outlet (alternate), Connection to Wetland 121.
As the majority of the improvements and construction activity are proposed to occur within
LHRP, the approval of the Dakota County Board and Metropolitan Council will be required for
the construction of Project 905. Since the approval of the project by the City Council, staff
members from the following agencies have been holding stakeholder meetings consistently to
coordinate compliance between the project design and Dakota County Park's Lebanon Hills
Storm Water Management Plan. The cities of Apple Valley, Eagan and Rosemount; Dakota
County Parks; Minnesota Department of Natural Resources; Vermillion River Watershed Joint
Powers Organization; Gun Club Lake Water Management Organization.
The draft Lebanon Hills Storm Water Management Plan was presented to the Dakota County
Physical Development Committee on July 26, 2005. At their August 2 meeting, the Dakota
County Board approved the release of the draft plan for public comment with the review period
extending from August 2 -September 30. The plan includes the discussions and consensus
developed via the mulit-agency stakeholder meetings. County Parks Department staff held an
open house to present a summary of the draft Plan and address any questions or comments from
the public at the Lebanon Hills Visitor Center on September 7.
Plan Roviow
The recommendations of the draft Lebanon Hills Storm Water Management Plan are summarized
as follows (and available for detailed review if so desired):
• Project 905 Construction . Area: As Project 905 is proposed to follow an alignment that
includes three LHRP water bodies and overland or piped drainage within the park, it is
appropriate to ensure the Project and Plan comply with each other. The following
improvements are comparable to the Project 905 improvements.
o Replace culvert outlet of Gun Club Pond (LP -23), include 10" orifice
L- o Lower Marsh Lake 2', from 905.3 to 903.3 Q'
o Storm SewerBio-swale connection from Marsh Lake to McDonough Lake
/ o Build berm at McDonough Lake to 889.0 for flood protection
o Maintain McDonough Lake (summer level), Structure Control Elevation 879.2
o Gravity Storm Sewer connection from McDonough Lake to LP -51 Lift Station
o Valve Pipe connection between McDonough Lake & Wetland 121
o Excavate Wetland 121 to enhance infiltration
o Replace & Upgrade LP -51 Lift Station
o No Design Discharge to Holland Lake
•
Project 905 Associated Improvements: The following improvements are associated with the
construction activities related to Project 905, primarily a result of the flood control
improvements (berming) at McDonough Lake.
o Raise access road to Lebanon Hills Visitor Center
o Replace bituminous trail with raised boardwalk (McDonough Lake)
o Construct additional trail along north & east side of McDonough Lake
o Shoreline Bioengineering (McDonough Lake)
o Winter Aeration System (McDonough Lake)
o Replace 27" culvert w/ 15" culvert between Schulze Lake & McDonough Lake
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• 120d' Street Improvements: 120"` Street adjacent to LHRP is located on the boundary of
Eagan and Rosemount and said maintenance responsibilities are accordingly shared between
the two agencies. The following improvements are related to the satisfactory operation of the
Project 905 improvements.
o Raise 120d' Street 2'+ for about 1400' (Total in 3 locations)
o Replace & Add culverts
Internal LHRP Improvements: The following improvements are inside LHRP and outside of
the Project 905 construction area, but related to the satisfactory operation of the Project 905
improvements.
o Cattail Lake Outlet
o O'Brien Lake Outlet
o Portage Lake Outlet
o Bridge Pond Outlet
o Valleywood Golf Course Pond Outlet
• EaLan Stormwater Mana}=ement Plan: The following improvements are included in the City
of Eagan's current stormwater management plan.
0 12" culvert from Pond 40(LP-7) to Jensen Lake
o Pre-treatment sedimentation basin (Jensen Lake)
o Bulkhead 21" storm sewer (south of Steeplechase)
Gerhardt Lake/Wheaton Pond: The following improvements are a revision of the City of
Eagan's 1990 Stormwater Management Plan, but comply with the current watershed
management organization boundaries.
o Wheaton Pond connection to Apple Valley storm .sewer system
0 6" culvert from Gerhardt Lake to Pond 11(BLP-3)
Additional staff comments follow regarding the draft Plan.
1. The recommended improvements are prioritized in the Plan, however recommended
responsibility/ownership for each option is not identified. The Plan should suggest how
responsibility is to be determined.
2. Improvement costs are identified, but revenue sources are not stated. The Plan could state the
positions expressed by the various agencies in the multi -agency stakeholder meetings and the
expected revenues for each project based upon the agencies' associated responsibilities. This
should also include the appropriate reimbursement of Eagan's downstream trunk storm sewer
costs. The Plan can detail County Parks staff's disagreements with each city's expected financial
contributions, as appropriate.
3. The Plan should recommend how to proceed to implement said improvements. The Plan should
recommend a process for each improvement including the basis for design, ownership of the
different options, cost responsibilities, schedules and executing agreements between agencies.
Finance Oi)tion
Ideally, the financing of the improvements proposed as a part of the draft Lebanon Hills Storm
Water Management Plan would be shared by the agencies managing the park; Dakota County and
the Metropolitan Council. From the perspective of the drainage areas impacting LHRP and the
downstream areas, it is evident that multiple agencies, including the City of Eagan, could share in
the funding of the Plan improvements. Based upon the City of Eagan's design and construction
of a storm sewer system including the capacity for the LHRP drainage, it is also apparent that
reimbursement of these incurred expenses, i.e. storm sewer trunk fees, is appropriate.
One cost share approach discussed as a part of the multi -agency stakeholders meetings that
appears to be favored by County staff is to collaborate and request $3,000_0gQJ!_'_Q0k state
bonding to construct the planned storm water improvements included as part of Project 905.
State or regional benefits include:
• benefits several state water bodies
• protects a DNR Trout Lake (Holland Lake)
• stops flooding of private property
• stops flooding of a major arterial (Cliff Road) that connects to State Highway 3
• protects public recreation and natural resources of a regional park.
This shared bonding request could possibly include all agency stakeholders (Eagan, Apple
Valley, Rosemount and Dakota County) which would broaden the legislative and constituency
base.
SUMMARY
The draft Lebanon Hills Storm Water Management Plan incorporates drainage improvements
throughout the Lebanon Hills Regional Park. Since a large majority of the drainage exits the park
through McDonough Lake and Wetland 121 and ultimately enters the City of Eagan's storm
sewer system at this point, it is very important that the city's Project 905 is compatible with this
plan. As much of the remaining area within LI -IRP also drains into the Eagan storm sewer system
and portions of Eagan drain into LHRP, it is crucial that the City of Eagan can support the final
version of the plan and its eventual implementation.
As presented in the draft Lebanon Hills Storm Water Management Plan, the recommendations are
acceptable as staff has found them to be primarily consistent with the City of Eagan`s Stormwater
Management Plan and Gun Club Lake Watershed Management Organization boundary. While
staff has some differences in opinions with some of the recommendations on a technical basis, the
insight of the multi -agency stakeholders meetings and the comprehension of the ecological focus
of the Plan adequately mitigate these differences.
Specifically with regards to Project 905 and the Storm Water Management Plan, the multi -agency
stakeholders group has developed consensus on a technical plan that has been incorporated in to
the LHRP Plan. That being the case, the determination of an appropriate cost sharing approach
must follow. The County Board's approval of the Lebanon Hills Storm Water Management Plan
is required in order to proceed with this effort and move towards construction of Project 905.
If 2006 state bonding is secured, as explained previously, Project 905 could begin construction
possibly in the late summer or early fall of 2006 (if construction plans were prepared concurrent
with the legislative session). If state funding is not secured, an alternative cost share approach
would have to be determined after the session, with the construction schedule established
accordingly.
PUBLIC WORKS COMMITTEE RECOMMENDATIONS:
1. Recommend the City Council's support of the draft Lebanon Hills Storm Water
Management Plan, including directing staff to prepare a letter of support for the draft Plan to
the Dakota County Parks Department accompanying suggestions for minor revisions or
additions; OR
2. Recommend the City Council direct staff to prepare a letter of opposition to the draft Plan to
the Dakota County Parks Department accompanying suggestions for significant revisions or
additions.