2016-025 Council Resolution - Laserfiche WebLink

Home Search

Option 2: Irrigating Public Spaces and Townhomes with Storm Water The water balance model indicates that the storm water stored can sufficiently supply water for irrigation of the public spaces and townhomes with minimal pond level fluctuations. Option 3: Irrigating all of the Mattamy Development with Storm Water The water balance model indicates that the storage area cannot supply enough irrigation water to support this option. The model showed that storage levels will reach significantly low levels and that the reuse system would require supplementation from the municipal water system. The cost to supplement the water reuse system with the municipal supply is not a cost that required with Option 1 or 2. In addition there will be vegetation issues if the storage area is drawn down this low, along with it is anticipated that residents will not desire to have the storage area this low. Option 2 is recommended because it provides the most surface water reuse without a fourth municipal utility system and individual service lines. Option 2 can be implemented without supplementation/connection to the municipal water system. 2.3.1 Pump and Pipe Materials Appendix C includes pump and forcemain layouts for each option, as well as suggested meter locations. The pump size should be determined by the irrigation designer, and they should be controlled by soil -moisture sensors, to ensure that watering is dictated by weather and soil conditions. The proposed forcemain is 2 to 4" diameter, high density polyethylene (HDPE). 2.3.2 Water Quality Prior to each irrigation season, it is recommended that the storage area be tested for water quality. The Minnesota Pollution Control Agency has recommended water quality parameters as outlined in Appendix D. If the parameters are not met, additional treatment should be considered to ensure the storage water remains of high enough quality to use for irrigation. 2.3.3 Ownership Recommendation It is recommended that the City own and operate the system, and within the townhome area, the City should have a maintenance agreement with the HOA where they are responsible for maintaining the system in the townhome area. 23.4 Metering, Usage, and Billing It is recommended that the park and berm irrigation systems be operated with independent meters so that the townhome maybe invoiced for their water usage to support maintenance of the system. Watering restrictions should remain in place for consistency and promote water conservation. 2.3.5 Permitting A Rice Creek Watershed District (RCWD) permit will be required. The project will meet volume reduction, treatment and rate control per RCWD rules. A Minnesota Department of Natural Resources (DNR) appropriations permit will also be required for the project. Feasibility Report Mattamy Homes Water Reuse WSB Project No. 2988-01