05/08/1995 Council Packet - Laserfiche WebLink

Home Search

Ms. Mary Kay Wyland April 20, 1995 Page 2 The design of the proposed development avoids direct impacts to wetlands in all but one basin. Overall, only 7,200 square feet (0.17 acre) of one wetland basin will be filled by the proposed project, approximately one percent of the wetland habitat on the site. This impact will be mitigated by the construction of 15,000 square feet (0.34 acre) of wetland habitat, resulting in a net increase in wetland habitat on the site. All of the wetlands on the site will retain their natural function of water retention. In addition to the water retention function of the wetlands, the construction of seven storm water treatment ponds will also serve to retain and treat storm water runoff from the site. Page 1, Paragraph 5 Presently there are 4 culverts (from Ponds #1, #2, #4, and #6), which re-route excess water from a portion of the western half of this project into the wetland area adjacent to Country Ditch #25. With the potential for the water table to rise as a direct result of this unnatural, additional drainage into this wetland arca, the adjacent landowners: of the 40 -acre parcel adjoining the far northern boundary of the project, of the 5 -acre parcel (1101 Holly Drive West), of 6275 Holly Drive West, and of 6265 Holley Drive West --- have serious concerns that the presently dray and functional areas of their properties, which directly abut this wetland, will become water- logged and unusable. The proposed development does not significantly alter the existing drainage pattern on the site. The culverts from Ponds 1, 2, 4, and 6 will route runoff from the western portion of the site to the wetland adjacent to County Ditch #25 (Basin A). However, this arrangement is not unnatural, as much of the area currently drains to this wetland in the undeveloped condition. The Lino Lakes LWMP requires developments to detain runoff on the site and discharge at rates no higher than those determined in the local water management study to prevent flooding of adjacent properties. Review of the development shows that discharge rates from the ponds on the site will not exceed the rates in the undeveloped condition. Page 1, Paragraph 6 There is a culvert from the pond located in Block 5, Lots 24-26 draining into the wetland identified as Basin G. Additionally two holding ponds: one in Block 5, Lots 29, 30„36, 37 --- and Pond #5 in Block 3, Lots 6 & 7, directly adjoin the wetlands, identified as Basins G and E without the use of a culvert to handle their overflow problems. The excess water from these basins drains off-site and has the same impact as above to the adjacent property owners east (1210 Holly Drive) of the project --- and south: a 10 -acre parcel, a 20 -acre parcel, and a 11.5 -acre parcel (1101 Holy Court East). The pond in Block 5, Lots 29, 30, 36 and 37 is hydraulically connected to a second basin in Block 5, Lots 24-26. The culvert in the downstream basin will control runoff from the entire pond. Pond 5 will discharge into the adjacent wetland basin in Block 3. Discharge from this basin will be controlled by the culvert under Road "B" to avoid flooding in the wetland south of Road "B" and adjacent properties. The design of the ponds and outlet structures will not allow discharge from the site at rates higher than in the undeveloped condition.