3.2 Water Quantity

  1. Drainage is conveyed through the subwatershed through several streams and channels as well as storm sewer and overland flow.  The HHPLS identified a few locations that are predicted to overtop during the 100 year event, as well as others with a minimal amount of freeboard.  More detail is available in the HHPLS.
  2. Development is predicted to increase the volume of stormwater runoff from the subwatershed, conveying greater nutrient and sediment loads to Lake Minnetonka.
  3. The HHPLS identified several locations where for both existing and future conditions higher velocities than desired may result in erosive velocities at outlets or culverts.   These include several road and railroad crossings.  Erosion control or energy dissipation measures may be required in those locations.
  4. Several landlocked basins are present in the subwatershed.  Within these landlocked basins, any future development or redevelopment should minimize creation of new stormwater volumes.  Outletting will generally be discouraged unless there is a demonstrated threat to property structures or public safety.