S.2 Stormwater Management

Intent
Minimize the negative impacts of the project, both on and off site, by maintaining a more natural hydrologic cycle through infiltration, evapotranspiration, and reuse.

Notes:
All governing rules and regulations for stormwater management apply to work covered by this section. The more stringent regulation shall take precedent.

Methods to achieve credits in this section shall be consistent with those found in the most current edition of the Minnesota Pollution Control Agency's "Minnesota Stormwater Manual".

Required Performance Criteria

1. Runoff Rate and Volume:
   1. Control the rate of runoff from the post-development site to match the runoff rates for the native soil and vegetation conditions for the 2-year and 10-year, 24- hour design storms.
   2. Prohibit discharge from the site for 1.1 inches of runoff from all new or redeveloped impervious (non-vegetated) areas.
2. Runoff Quality:
   1. Provide treatment systems designed to remove 80% of the post-development Total Suspended Solids (TSS).
   2. Provide treatment systems designed to remove 60% of the post-development Total Phosphorus (TP).
3. Operations and Maintenance Manual All stormwater BMPs must have an Operations and Maintenance manual created which outlines maintenance requirements and schedules for completion. Operations and Maintenance manuals shall be recorded with the County Registrar.

Compliance Tools and Resources

• "Minnesota Stormwater Manual" (Minnesota Pollution Control Agency)
  • Standard Curve Numbers
  • Stormwater Treatment BMPs and related information