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Feasibility Report Northeast Lino Lakes Drainage Improvement Project WSB Project No. 2029-790 Page 8 4. PROPOSED IMPROVEMENTS 4.1. Alternatives Considered In consideration of the City’s Comprehensive Plan where this area is guided for urban and mixed uses (Appendix A, Figure 5) it was determined that the existing drainage system would need to be addressed. Multiple alternatives were considered based on the future needs of the area (Table 2). Table 2. Future Land Uses Land Use Area (acres) Commercial 98 High Density Residential 19 Industrial 412 Large Lot Residential 46 Low Density Residential 179 Medium Density Residential 61 Mixed Use 340 Open Water 72 Park, Recreational, or Preserve 16 Right-of-Way 51 TOTAL 1,294 As the existing county drain system is not sufficient to handle the increased runoff from a developed watershed. Options were considered to provide capacity for development, with the goal of limiting adverse impacts to downstream landowners and natural resources. The following options are discussed in greater detail in Appendix D. Option 1: Existing System to Remain The existing system is in need of maintenance. The RCWD completed a study in 2014 outlining system improvements. Even with the system improvements, the capacity of the existing system is not sufficient to develop the area consistent with the City of Lino Lakes’ Comprehensive Plan. For property owners to make improvements in this drainage area, per RCWD rules, they may need to dedicate 45% of their developable land for stormwater management including ponding of back-to-back 100-year flood events and infiltration requirements. This area has tight soils and alternatives to infiltration are costly and limited. Spray irrigation is temporarily being used to meet the RCWD requirements at the McDonald’s site until a regional BMP is constructed. The existing system does not provide any water quality treatment upstream of Peltier Lake which is classified as an impaired waterbody. Simple estimates indicate that the existing system discharges 588 pounds of phosphorus and 1,028 tons of total suspended solids to the lake on an annual basis. Any proposed project must not impair water quality or flood storage within or downstream of Peltier Lake.