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(d) Proposed development design shall: <br /> 1. Maintain or decrease runoff volume; <br /> 2. Decrease erosion and sedimentation; <br /> 3. Maintain or decrease flow frequency, duration, and peak runoff rates; <br /> 4. Increase infiltration (groundwater recharge) or filtration; <br /> 5. Maintain existing flow patterns; <br /> 6. Reduce time to peak flows by increasing the time of concentration to and through storm sewers; <br /> 7. Provide storage of stormwater runoff on site; <br /> 8. Avoid channel erosion; <br /> 9. The proposed project must not adversely affect water level off the site during or after construction; <br />and <br /> 10. The proposed activity may not reduce hydraulic efficiency of the drainage ways at any point up- <br />gradient of the applicant's parcel boundary. <br /> (e) Landlocked basins. A landlocked basin may be provided an outlet only if it: <br /> 1. Retains a hydrologic regime that complies with the requirements of the local governmental unit <br />(LGU) responsible for administration of the Wetland Conservation Act (WCA); <br /> 2. Provides sufficient dead storage volume to retain back to back 100-year, 24-hour rainfalls and <br />runoff; and <br /> 3. Does not create adverse downstream flooding or water quality conditions as a result of increased <br />discharge rate or volume, or other factors. <br /> (f) All plans shall be consistent with National Pollutant Discharge Elimination permit (NPDES) <br />requirements, the Lino Lakes engineering design standards, the Lino Lakes stormwater design standards, <br />and the filing or approval requirements of Rice Creek Watershed District, Vadnais Lakes Watershed <br />Management Organization, Anoka County, Minnesota Department of Natural Resources, Minnesota <br />Department of Transportation, Minnesota Pollution Control Agency, U.S. Army Corps of Engineers, State <br />of Minnesota Stormwater Manual or other regulatory agencies. <br /> (g) The City of Lino Lakes may develop a comprehensive stormwater management plan (CSMP) as an <br />alternative way to meet the stormwater requirements of the local watershed agencies for development <br />within a defined area and a common resource of concern (ROC). The CSMP will be submitted to the <br />applicable watershed district for review and must comply with the requirements of the watershed district. <br /> (3) Stormwater management plan modeling requirements. <br /> (a) A hydrograph method or computer program based on Natural Resources Conservation Service <br />Technical Release #20 (TR-20) and subsequent guidance must be used to analyze stormwater runoff for the <br />design or analysis of flows and water levels within and off the project site. Composite curve numbers shall <br />not include directly connected impervious surfaces. <br /> (b) In determining curve numbers to model runoff in the post-development condition, the hydrologic <br />soil group (HSG) of areas within construction limits is to be shifted down one classification (or one-half <br />classification for HSG A) to account for the impacts of grading on soil structure unless the project <br />specifications incorporate soil amendments in accordance with Rice Creek Watershed District Soil <br />Amendment guidelines.