Town of Merrimack

Merrimack Stormwater Laws & Regulations

The Town of Merrimack regulations are compliant with the National Pollutant Discharge Elimination System (NPDES) through municipal regulation Merrimack Code Part II Chapter 167. The town’s Municipal Separate Storm Sewer System (MS4) requires Merrimack to administer and enforce compliance with stormwater discharge permits in an effort to decrease stormwater pollutants and increase overall water quality. The town is part of the Souhegan Watershed Association, which works collaboratively with other municipalities within the local watershed to improve and maintain the environmental quality of the Souhegan River and its watershed.

EXCERPT- Merrimack Stormwater Ordinances, May 2014

Chapter 167. Stormwater Management Standards

167-3. Applicability

Prior to disturbance, the responsible party shall submit a SWMP to the Community Development Department (CDD) for any tract(s) of land that results in a total disturbance of 20,000 or more square feet of land.

167-4. SWMP Requirements

B. Post-construction stormwater management.

1. Design standards. Design of post-construction stormwater management shall be in accordance with, at a minimum, the design guidance set forth in the New Hampshire Stormwater Manual, which is hereby incorporated by reference.
2. Post-construction meeting. The responsible part and its engineer or technical representative shall attend a post-construction meeting with CDD and DPW.
3. Responsibility. The responsible party shall install, inspect, report, operate, and maintain any post-construction stormwater management and erosion control measures.
4. Bond release requirements.
  1. Ongoing inspection and operational maintenance requirements for water quality measures required by the SWMP shall be a condition of site plan approval or, in the case of other development not subject to site plan approval, included as a covenant in the underlying deed(s).
  2. Attendance by the responsible party at a post-construction meeting.
  3. As-built plans bearing the seal and signature of a New Hampshire registered PE.
  4. Approval of the bond release by both CDD and DPW.
5. Reporting. Each SWMP shall require annual site inspections by the responsible party that shall be documented and, at a minimum, include review of stormwater flow paths, accumulation of any sediment, condition of contaminant control devices, stormwater quality observations, corrective actions and time frames. All records of the inspections shall be submitted to CDD.