09-08-1986 Council Packet - Laserfiche WebLink

Home Browse Search

1.ARKIN. Ilc)FFMAN, DALY 8. I.I\I)(;IlI:N, IXT). Mayor Butler and City Council Members September 8, 1986 Page 3 Mr. Ulrich as applied for both a conditional use permit and a variance as required. Again, it must be stressed that there is nothing in the City ordinances that regulates the installation of the well itself for geothermal use; nor the volume of water it discharges. 3. Sufficient hardship exists so as to justify the issuance of a variance for the installation of the subject pipe. There are f-ur options for the discharge of groundwater which is appropriates for the geo-thermal unit. First, additional wells can be drilled and the water can be pumped down into those wells after it is circulated thro-igh the unit. Second, the water can be discharged into a ponding area located in the southeast corner of the ajacent property. Third, a discharge pipe can be buried underground from the geo-thermal unit to Lake Minnetonka. Fourth, the water can be discharged directly on t- the surface of the ground and allowed to flow overland to Lake M,:,netonka. The first option, is really no Dption at all. When additional wells are dug, the ground water will rise in the wells and effectively prevent the draining of water from the system back down into the water table. Discharging the water into the ponding area in the southeast corner of the property poses several hazards. First of all, this water ultimately finds its way into Lake Minnetonk4. By discharging into the pond, the water will travel overland until it reaches that destination. That leaves the possibility of the water picking up pollutants and contaminants that are washed into the ditch area through which the water would flow. Additionally, there is a 12 inch culvert through which the water must pass. There is a strong likelihood that this culvert will freeze in the winter time, thereby preventing the discharge water from reaching the lake. Ultimately, this would cause the system to malfunction when the pond reached its maximum capacity. Should that culvert not freeze over, there is the possibility that as the water flows to the lake, it will freeze at the point where it enters the like and cause an ice buildup whic:i would ultimately dam the drainage ditch involved. Another option is to discharge the water from a pipe set feet back from the lake. The water then would follow the natural er course over the 75 foot .:area. Doing so, would allow the water to pick up fertilizer, soils, and the like and carry it into the lake. It is also likely that there could be substantial erosion. The overflow of water could cause open ice on the lake, which would be a hazard to persons using the lake in the winter time.