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This area is west of TH 47 and east of 149th Lane. The area in question is adjacent to the large DNR wetland which abuts TH 47. The petition was initiated by the resident at Lot 3, Block 1, Ramsey Meadows 4th Addition (5410 149th Lane NW). The homeowner contacted the City about water standing in the backyard. Review of the grading plan indicates this area was part of the wetland mitigation plan prepared for the plat and is controlled by the Wetland Conservation Act rules. There is a draintile that connects the backyard to the DNR wetland. Stormwater from the wetland flowed into the back yard which is lower than the wetland. A drainage and utility easement is recorded over the low area of the property. The DNR lists the normal water level of the wetland as 860.0. There is a retaining wall with steps in the backyard, with an elevation at the lowest step at approximately 860.1 The backyard slopes down from the steps so there will be water present when the wetland is at normal elevation. There is a pipe under TH47, which is the outlet for the wetland, and there is an outlet structure on the pipe that controls the water elevation. The lowest point on the structure was approximately 2 1/2 feet above the normal water elevation at the time the elevated water was occurring last summer. The structure was quickly modified to lower the outflow elevation in an attempt to alleviate the high water concern. The overflow is now 0.8 feet above the normal water elevation, but the structure can still be modified slightly to lower the invert to the approximate normal water level of the wetland (860). Funding Source: The funding source for this improvement would be the Stormwater Utility Fund. It is estimated that this structure modification would cost between $2,000 - $5,000, but staff would like to meet with local contractors to discuss all options prior to making a final determination. Staff Recommendation: Staff recommends modifying the outlet structure to lower the wetland outfall elevation, placement of a flared end section, and removal of vegetation around the outlet pipe. Committee Action: Motion to recommend to the City Council that staff seek quotes to modify the outlet structure to lower the outlet elevation of the wetland. Attachments Project Location Map Ramsey Meadows 2nd Additon Plat Resident Petition Petition Map Section 2 of Hakanson Anderson Report Form Review Inbox Reviewed By Date Tim Himmer Len Linton 05/10/2012 03:01 PM Len Linton (Originator) Len Linton 05/10/2012 04:08 PM Tim Himmer Len Linton 05/11/2012 08:35 AM Len Linton (Originator) Len Linton 05/11/2012 09:51 AM Tim Himmer Len Linton 05/11/2012 11:03 AM Len Linton (Originator) Len Linton 05/11/2012 11:08 AM Tim Himmer Tim Himmer 05/11/2012 11:28 AM Brian Olson MaryJo Warner 05/11/2012 11:29 AM KurtUlrich KurtUlrich 05/11/2012 11:55 AM Form Started By: Len Linton Started On: 05/09/2012 02:46 PM Final Approval Date: 05/11/2012