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Feasibility Report Northeast Lino Lakes Drainage Improvement Project WSB Project No. 2029-790 Page 11 within the study area and improve drainage conditions throughout the Northeast Lino Lakes Area. There are multiple ponding locations proposed with the Northeast Lino Lakes Comprehensive Stormwater Management Plan. At this time, it is proposed to utilize existing wetland complexes for flood storage by providing an outlet control structure with operable gate at the normal water level. In the event of a 100-year design storm, the gates can be closed to minimize the risk of increasing the flood stage on Peltier Lake, and the wetlands would store the water until the gates are opened after the flood threat on Peltier Lake has passed. The exact location and design of these regional storage facilities will be determined as the design progresses. It will be expected that the storage areas will experience a significant bounce in elevation during 100-year storm event and will need to be planted with a suitable planting palette that can tolerate periodic inundation to maintain vegetation. 4.4. Storm Water Quality The study area will include a variety of measures to provide treatment and improve water quality in Peltier Lake and the Anoka Chain of Lakes to minimize impacts related to this project. All individual developments will be required to manage stormwater on site to the current and applicable RCWD rules. It is anticipated the study area will include a water quality treatment train with sedimentation BMPs located in upland areas designed to remove solids and particulate matter. This will be combined with surface and media filtration to remove dissolved particulates, nitrogen, and phosphorus prior to entering the new storm sewer. The existing and proposed total phosphorus loading from the study area to Peltier Lake were evaluated at a conceptual level, using event mean concentrations from the Minnesota Stormwater Manual for the general land use types within the study area. Without any water quality treatment, the development of the study area would result in nearly doubling the total phosphorus loading to Peltier Lake annually. The City of Lino Lakes stormwater management ordinance and the RCWD rules will require water quality treatment practices be implemented for all new developments. The required BMPs are estimated to remove roughly 600 pounds of total phosphorus annually, which would result in a total load reduction of 130 pounds from existing conditions. Refer to Appendices B and E for proposed design requirements and conceptual details for the study area. 4.5. Permits and Approvals Construction of the new crossing, channel and outlet improvements will disturb more than one acre of land and will require a National Pollution Discharge Elimination Systems (NPDES) General Stormwater Permit [MNR 100001] that must be obtained by Lino Lakes from the Minnesota Pollution Control Agency (MPCA).