| It has come to our attention through SEH maps
that the Southwest loop holding pond of the Highway 55/62 interchange may
dewater part of the Groundwater
Flow to the Coldwater Spring. If you look at the map showing groundwater
flows, the groundwater flows through the Secondary Fractures, shown
in blue, from the Southwest, to the Primary Fracture, shown in green, to
the Coldwater Spring. The Surface Topography Map shows the Spring lies at a natural elevation of 242 meters. The Hwy 55/62 interchange is at a natural elevation of 252 meters. The problem is, in two maps for the construction of the interchange, MnDOT will dig the drainage pond in the Southwest loop to a depth of 240 Meters, with a normal water level of 241 meters. Because secondary fractures run through this area (see groundwater map), some water may drain backwards from the Coldwater Spring at 242 meters to the pond at 241 meters. MnDOT is estimating that the bedrock is at 240 meters, but if gravity prevails, with the spring at a higher level than the holding pond, part of Coldwater could be rerouted through MnDOT drainage ditches. Thanks to the political decision of the Board of Water and Soil Resources, the source water for Coldwater, and the interchange, is in the Lower Minnesota River Watershed District, while Coldwater Spring is in the Minnehaha Creek Watershed District. Lower Minnesota still does not have permitting authority, leaving MnDOT very unregulated, in the construction of this drainage pond, and interchange. There is an agreement between MnDOT an Lower Minnesota River Watershed, but it may prove to be a weak one. We are working with Minnehaha Creek, MnDOT and Lower Minnesota River to try and come to an agreement to correct this situation. Coldwater did receive help from our representatives, State Representives, The Mayor, our City Council Members and Governor Ventura to protect Coldwater. This is partly why the liner was put in place. |
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