Minimum Control Measure 5: Construction Site Stormwater Runoff Control

As stormwater flows over areas altered by development, it picks up pollutants such as oil and grease, fertilizers, pesticides, and heavy metals. The flow rate of stormwater runoff is faster on developed land than on undeveloped areas, causing flooding and erosion if stormwater controls are not in place or are not properly designed. MS4s need strategies and management practices to reduce the amount of pollutants and rate of stormwater runoff after construction is completed. Proper planning and design leads to cost-effective stormwater management for new development and redevelopment.

Permit Requirements

Develop and implement a program that:

  • Includes a combination of management practices that will reduce the discharge of pollutants to the maximum extent practicable;
  • Uses a law or other regulatory mechanism to address post-construction runoff from development and redevelopment; and
  • Ensures adequate long-term operation and maintenance of management practices, including monitoring.

Develop, implement, and enforce a program to address stormwater runoff from new development and redevelopment projects that disturb one or more acres of land that discharge into the small MS4.

Include projects disturbing less than one acre in the program:

  • If it is part of a larger common plan of development or sale, or
  • If controlling such activities in a particular watershed is required by DEC.

Ensure that controls are in place to protect water quality and reduce the discharge of pollutants to the maximum extent practicable.

Develop, implement, and provide adequate resources for a program to inspect development and re-development sites and to enforce and penalize violators.

Develop measurable goals and select appropriate management practices to ensure the reduction of all pollutants of concern in the post-construction stormwater discharges to the maximum extent practicable.

Desired Outcome

Reduce the amount of pollutants and rate of stormwater runoff from developed sites after construction has been completed.