New Hampshire Small MS4 General Permit
Resources relating to the New Hampshire Small MS4 General Permit and where to go if you need additional information.
Disclaimer: EPA is the permitting authority for the MS4GP. NHDES does not have any regulatory authority over the MS4GP and solely provides support for permittees.
The MS4GP was reissued by EPA on January 18, 2017. The final permit reflects modifications to the 2013 Draft Small MS4 General Permit and the 2015 renoticed permit sections. EPA proposed modifications to the 2017 NH MS4 General Permit on April 23, 2020 and finalized those modifications on December 7, 2020. Small MS4 owners and operators in urbanized areas (based on 2010 census) are required to apply or reapply for coverage under the 2017 MS4GP, unless granted a waiver by EPA.
The owners/operators of Small MS4s may include municipalities; county facilities, such as prisons/hospitals; districts; federal facilities, such as military bases; and state facilities, such as highways. The MS4GP requires MS4 operators to develop a stormwater management program that controls pollutants from all of the MS4 discharge points to the “Maximum Extent Practicable.” The MS4GP requires that the stormwater program include the six minimum control measures listed below as well as an annual report to EPA summarizing progress toward achieving specific measurable goals:
- Public education and outreach on stormwater impacts.
- Public involvement/participation during program development.
- Illicit discharge detection and elimination.
- Construction site storm water runoff control.
- Post-construction storm water management in new development and redevelopment.
- Pollution prevention/good housekeeping for municipal operations.