4.5 Water Quantity Issues

Stormwater Conveyance Issues

Drainage is conveyed through the upper watershed through streams and channels to Lake Minnetonka and other intervening waters.  The Upper Watershed Stream Assessment identified numerous locations on those streams where erosion and bank failure were evident.  In addition, there are numerous other streams and channels that drain the upper watershed that have not been identified and assessed that may also experience erosion that could be a source of downstream sediment and nutrient loading.  Additional stormwater volume generated by new development may cause new erosion, and stabilization may be necessary to reduce the need for future repairs.

Impact of Future Development

Development and redevelopment in the watershed is predicted to increase the volume of stormwater runoff conveying pollutant loadings from the watershed.

Landlocked Basins

Several of the subwatersheds contain landlocked basins that have no natural outlet, or that outlet only under certain conditions.