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A Proposal for Lake Amelia Subwatershed Management Plan for the City of Lino Lakes | 1 Mr. Andrew Nelson Environmental Coordinator City of Lino Lakes 600 Town Center Parkway Lino Lakes, MN 55014-1182 Re: Lake Amelia – Scope of Work for Stormwater Management Options Feasibility Study Dear Mr. Nelson: WSB is pleased to submit this scope of work and cost estimate to complete a Feasibility Study on stormwater management options for the subwatershed north of Lake Amelia in the City of Lino Lakes (City), and Vadnais Lakes Area Water Management Organization (VLAWMO). Task 1 – Staff Meetings (18 hours $2,000) Four meetings and one site visit are anticipated and can be adjusted based on the recommendation of the City and watershed staff. An initial kick-off meeting will serve as an opportunity to review the goals of the study, the approach, and the schedule. Subsequent meetings are anticipated for Tasks 3, 4 and 8. Task 2 – Existing Conditions Review (26 hours $3,300) WSB will assemble all available data in a single GIS database. The data will include parcel information, stormwater infrastructure, topography, aerial imagery, wetlands, bathymetry, biological survey, land use and soil data. Most of the data will be available from the City, VLAWMO, and public sources. The terrain data will be used to identify the drainage area limits and develop a catchment level delineation. WSB will send a survey crew on-site to obtain detailed topography of the ditch, slopes, erosion, stormwater structures, and adjacent grades to better analyze the current drainage system and help plan the proposed improvements. As part of the existing conditions review, WSB will perform monitoring to better understand the water quality and hydrology within the ditch and in Lake Amelia. TP and TSS samples will be taken once a month through the growing season at a minimum of two locations within the lake. Base flow rates will also be measured in the ditch to quantify hydrology from the drainage area. We anticipate monitoring to continue beyond completion of the final report in Task 8. The samples and flow rate measurements will provide detailed pollutant loading information from the ditch and corridor along with providing baseline water quality data for Lake Amelia. As the Lake Amelia drainage area develops, having this baseline information will be useful in tracking any changes in water quality due to land use changes within the watershed. WSB will coordinate with the City to obtain access to the site for a field reconnaissance visit and survey. City and VLAWMO staff will be invited to share their expertise and knowledge of the study area. SCOPE OF WORK BACKGROUND Located in the southeastern corner of the City, Lake Amelia is a valuable natural resource identified as a lake of biological significance. The lake does not have any current water quality impairments, however, Lake Wilkinson located downstream is listed as impaired for nutrients. WSB recently completed TMDL reporting for Lake Wilkinson which provides for a detailed understanding of the project area and the TMDL requirements. A private ditch flows from northeast to southwest collecting drainage from approximately 340 acres. Portions of the ditch are flanked by wetlands and the ditch corridor is situated in a Zone A floodplain. Currently, the ditch is showing signs of erosion, sediment build up, and failing culverts. The City has been required to perform maintenance to temporarily alleviate these drainage issues. WSB understands that a long term solution and management plan is sought by the City and VLAWMO to not only relieve the current issues, but plan for additional amenities and improvements within the study area.