Agenda - Environmental Policy Board - 03/02/2015

Home

Environmental Policy Board (EPB) Meeting Date: 03/02/2015 Submitted For: Len Linton, Engineering/Public Works By: Len Linton, Engineering/Public Works 5. 1. Information Title: Consider Surface Water Management Plan Update Purpose/Background: State Rules and Statutes require all Cities to have a Surface Water Management Plan. These regulations also require updates to the plan on a regular basis. The first Comprehensive Storm Drainage Plan was approved in 1980. It was revised in 1997 and again in 2002. The plan was updated and renamed the Storm Water Management Plan (SWMP) in 2008. This plan was intended to be revised in 2015. The Lower Rum River Watershed Management Organization (LRRWMO) adopted their Third Generation Rules in 2012. The state regulations require that all local Storm Water Management Plans be updated within 2 years of adoption of revised Watershed Management Organization Plans. The Minnesota Pollution Control Agency was in the process of revising the Permit for the Municipal Small Separate Stormsewer Systems (MS4) and the Construction Stormwater Permit when the LRRWMO plan was adopted. The Cities of Ramsey, Anoka and Andover all applied for an extension of the deadline from the LRRWMO for revising their SWMPs until after the MS4 Permit was adopted so that required ordinance changes could be made once instead of several times. The extensions were approved. The changes contained in the MS4 Permit, Construction Stormwater Permit and LRRWMO covered the following areas: 1. Lowering the size of a project requiring a permit from 5 acres to 1 acre. 2. Requiring infiltration on site of the first 1" of runoff from all new impervious surfaces. 3. Limiting discharge from the site for the 2 year, 10 year and 100 year storms to the existing rate for each storm. 4. Reducing the amount of Total Suspended Solids and Total Phosphorus in runoff leaving the site. These goals can be achieved through the following measures: 1. Construction of infiltration or water reuse practices on site such as infiltration trenches, rain gardens, tree trenches or water re -use practices. 2. Constructing detention facilities that retain the peak flow and discharge it at a slower rate. 3. Construction of wet ponds that provide adequate time for settling of the Total Suspended Solids and Total Phosphorus and prevent resuspension with the next storm event. Attached to this case is an updated Surface Water Management Plan, which does show where revisions are proposed. This is a large document and thus, the attached SWMP is a redlined version, which will make it easier for the Board to see exactly where revisions are proposed. Staff from the Engineering Department will be attending this evening's meeting to review the proposed revisions to the SWMP and address questions the Board may have. Staff is seeking a recommendation from the EPB for the City Council to adopt the updated SWMP. After review by the EPB, the SWMP will also be reviewed by the Public Works Committee and then, ultimately, by the City Council. Action: Motion to recommend that City Council adopt the updated Surface Water Management Plan.