Agenda - Environmental Policy Board - 08/04/2014

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Sec 117.384 -410 Revised July 29, 2014 to include 2013 Construction Stormwater Permit, 2013 MS4 Permit requirements and 2012 LRRWMO Third Generation Plan [ate, additions] (f) Exemption. The mill and overlay or rehabilitation of a public roadway that does not create additional impervious surfaces; and sidewalk or trail projects are exempt from these stormwater requirements. These projects may be subject to other regulations. At a minimum these facilities must conform to the most current technology as reflected in the current version of the Minnesota Pollution Control Agency's publication, "Protecting Water Quality in Urban Areas" and the current requirements found in the same agency's NPDES permits for stormwater associated with construction activities. (Code 1978, § 9.27.12; Ord. No. 06 -32, § 1, 11 -28 -2006) Sec. 117 - 394. - Minimum protection for natural wetlands. (a) Runoff must not be discharged directly into wetlands without appropriate quality (i.e., treated) and quantity runoff control, depending on the individual wetland's vegetation sensitivity. See the current version of the Minnesota Pollution Control Agency's publication, "Storm -Water and Wetlands: Planning and Evaluation Guidelines for Addressing Potential Impacts of Urban Storm -Water and Snow -Melt Runoff on Wetlands" for guidance. The minimum level of treatment required for discharge to wetlands is to meet the NURP Guidelines as follows: • A permanent pool ( "dead storage ") volume below the principal spillway (normal outlet) which shall be greater than or equal to the runoff from a 2.5 inch storm over the entire contributing area assuming full development. It shall have an annual removal efficiency of 60% total phosphorus and 90% total suspended solids. • A permanent pool average depth (basin volume/ basin area) which shall be >3 feet, with a maximum depth of 10 feet. • Pond outlets shall have skimmers, submerged outlets or other devices that extend a minimum of 6 inches below the water surface and minimize velocities of water passing under the skimmer to less than 0.5 feet per second for rainfall events having a 99% frequency (1 year storm event). (b) Wetlands must not be drained or filled, wholly or partially, unless replaced by either restoring or creating wetland areas of at least equal public value. Compensating for the impact by replacing or providing substitute wetland resources or environments with those of at least equal public value. Compensation, including the replacement ratio and quality of replacement should be consistent with the requirements outlined in the rules adopted by the board of water and soil resources to implement the Wetland Conservation Act of 1991 including any and all amendments to it. (c) Work in and around wetlands must be guided by the following principles in descending order of priority: (1) Avoid both the direct and indirect impact of the activity that may destroy or diminish the wetland. (2) Minimize the impact by limiting the degree or magnitude of the wetland related activity and its implementation. Rectify the impact by repairing, rehabilitating, or restoring the affected wetland environment with one of at least equal public value. (4) Reduce or eliminate the adverse impact over time by preservation and maintenance operations during the life of the activity. (Code 1978, § 9.27.13; Ord. No. 06 -32, § 1, 11 -28 -2006) (3) Ramsey, Minnesota, Code of Ordinances Page 11