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SUNWOOD DRIVE WETLAND MITIGATION By: Steven J. Jankowski, City Engineer Background: The City wishes to extend Sunwood Drive west from its current terminus at Krypton Street to the intersection with County Road #57. Immediately west of Krypton Street, the proposed alignment crosses DNR Wetland #114P. The construction of the proposed Sunwood Drive across the wetland has been determined by the DNR to be allowable by constructing one half of the crossing by placing fill in the wetland and the other half being an open span bridge. As mitigation for filling the wetland, the DNR has indicated they would like to see the quality of Wetland #114P upgraded by raising the groundwater table from its current elevation. To facilitate this, you will recall that we retained John Oliver & Associates to prepare the necessary background and engineering. John Bertelson, Project Engineer, has prepared an engineering report summarizing the work needed to be done to meet this objective. This report is included under separate cover. This report has been forwarded to the DNR for review to ensure that it fulfills their expectations of the mitigation. In addition to DNR approval, it is also necessary to obtain approval from Anoka County due to the fact that County Ditch #43 runs through the middle of Wetland #114P. The attached report summarizes the activities which need to occur in order to receive County approval. The preparation of this report is the necessary step toward receiving County approval. This report has been forwarded to the County Engineer for his review and comment. According to Minnesota Statutes 103, the following tasks must also be performed to allow the County to grant permission for the ditch block: · A petition for the improvement must be submitted by the City. · A public hearing on the project must be held by the County. · The petitioner must agree to be responsible for the cost of the installation and maintenance of the improvements, in this case, the ditch block. · Flowage easements must be obtained from five property owners whose properties will lose drainage rights originally provided by the construction of the ditch. During the process of preparing this report, it also became apparent that the construction activity associated with this project would provide an opportunity to address the periodic spring flooding problem which the City experiences on 153rd Avenue. It was observed that the reconstruction of the County Ditch to its original cross section through the first 800 feet south of the roadway would provide an outlet for water in this northern lobe of the wetland. This would prevent the storm pipe openings from freezing, causing water to back up onto the roadway. Since the ditch cleaning proposed is considered a maintenance operation, no permits or approvals are required for this work.