Amherst Wetland Conservation District Ordinances

The following is an unofficial copy of the Amherst Wetland Conservation District Ordinances. Official copies of all ordinances are available at the Town Hall.

Wetlands Conservation District

Section 4-11 Wetland Conservation District
General The Wetland Conservation District is hereby determined to be those areas identified or delineated as poorly drained or very poorly drained soils, or as bodies of water by the National Cooperative Soil Survey through field mapping surveys completed in 1970 and shown on its field mapping photographic sheets for the Town of Amherst, New Hampshire. The Wetland Conservation District as herein defined as shown on a map designated as:

“U.S. Department of Agriculture Soil Conservation Service Town of Amherst, Hillsborough County, New Hampshire Soil Survey, November 1970

Amherst Wetlands Conservation District Map adopted 1973 Amended March 1975 (3-4-75) and is a part of the ‘Zoning Map’ of the Town of Amherst, NH

In all cases where the Wetland Conservation District is super-imposed over another zoning district in the Town of Amherst, that district whose regulations are the more restrictive shall apply.

In the event an area is incorrectly designated as being poorly drained or very poorly drained soils on the Town of Amherst Wetland Conservation District map and evidence to that effect is satisfactorily presented to the Building nspector or Zoning Administrator, the restriction contained in this section shall not apply. Conversely, in the event that an area not so designated has poorly drained or very poorly drained soils within the meaning of the aforementioned definition, then the restriction contained in this section shall apply. Such evidence may be obtained by adequate on-site soils investigation and analysis conducted by a certified soil scientist or certified wetland scientist.

The location of a wetland boundary in any particular case must be determined by on-site inspection of all three characteristics of wetlands, namely, hydrology, hydric soils, and hydrophytic plants. Said inspections shall conform to standards set forth in:

Corps of Engineers Wetlands Delineation Manual, Technical Report Y-87-1, Environmental Laboratory, Department of the Army, 1987.

Field Indicators for Identifying Hydric Soils in New England, Version 2, New England Interstate Water Pollution Control Commission, 1998.

Chapters Wt 100-800 of the NH Code Of Administrative Rules, April 21, 1997, as amended.

In the interest of public health, convenience, safety and welfare, the regulations of the Wetland Conservation District are intended to guide the use of areas of land that have soils that are saturated or inundated for extended periods of time during the growing season, and their surrounding buffers.

The specific intent of this District is:

To prevent the development of buildings and land use on naturally occurring wetlands, which would contribute to pollution of surface and ground water. 3-6-73

To prevent the destruction of natural wetlands which provide flood protection, recharge of ground water supplies, retention of sediments, attenuation of nutrients, augmentation of stream flow during dry periods, and important wildlife areas.

To prevent unnecessary or excessive expenses to the Town to provide and maintain essential services and utilities which arise because of inharmonious use of wetlands.

To encourage those uses that can be appropriately and safely located in the wetland area.

To protect water supplies, aquifers and aquifer recharge areas.

A. Permitted Uses

Any of the following uses, which may require a permit, and that do not result in the erection of any structure and that are otherwise permitted by the Ordinance:

Forestry - tree farming (see Part B)
Agriculture (see Part B)
Well and well lines
Wildlife refuge
Parks and such recreation uses as are consistent with the purpose and intentions of Section 4-11
Conservation area nature trails
Open space as permitted by subdivision regulations and other sections of this Ordinance
Minimal impact crossing of wetlands and their buffers by roads, bridges and driveways, subject to Planning Board review and approval.
Other uses consistent with the intent of the ordinance as approved by the Planning Board pursuant to Part D below.

B. Special Provisions

No wetland may be used to satisfy minimum lot size requirements in any zone.
No septic tank or leachfield may be located closer than seventy-five (75) feet to any wetland.
No structure shall be erected within fifty (50) feet of any wetland.
A naturally vegetated buffer of twenty-five (25) feet shall be maintained from the edge of any wetland.
A naturally vegetated buffer of one hundred (100) feet shall be maintained from the edge of any Public Water Protection Wetland, as defined in Part C of this ordinance.
Except as determined by the Planning Board there shall be no alteration of contours and no filling of land within a buffer. No structures, parking areas or driveways (paved or unpaved) shall be located within a buffer. Within a buffer, the footprint of an existing structure, parking area or driveway shall not be expanded.
A minimal impact crossing of wetlands and buffers for roads and driveways shall be permitted only when there is no other feasible alternative to provide access to a site, as determined by the Planning Board.
Forestry and tree farming in buffers shall be conducted in accordance with Best Management Practices for Erosion Control on Timber Harvesting Operations in New Hampshire, published by the NH Department of Resources and Economic Development, as amended.
Agricultural activities in buffers shall be conducted in accordance with the Manual of Best Management Practices for Agriculture in New Hampshire, published by the NH Department of Agriculture, as amended.
A “Water Resource Management Plan” which provides for substitutes for wetlands restrictions and setbacks may be submitted to the Planning Board. See Part D.
Nothing in this Part B, Special Provisions shall be construed as prohibiting the permitted uses contained in Part A above.

C. Public Water Protection Wetlands

The town’s wetlands ranked highest for their critical role in protecting public water supplies shall be designated as Public Water Protection Wetlands (See the Amherst Wetland Assessment And Prime Wetland Designation Project report dated January 2000).

Witches Brook Theriaults Marsh Stump Pond Ponemah Bog Glover Beds Homestead Commons Thibodeau Bog Ponemah Hill Complex J & J Party Outlet Nolan Pond Maine RR Sand Pit Baboosic Lake Horace Greeley Triangle Weimont Souhegan Three Beaver Brook South Meeting Place North Embankment Road Souhegan Two Souhegan One Ross Bird Sanctuary Pond Parish Outlet

Belden’s Mill North Baboosic Jasper Valley Honey Pot Pond Curtis Well Holt Road Currier Land Corduroy/Dog Pound St. Patricks Cemetery Post Road & Courthouse Hertzka Atherton Southfield Currier Lumber Boardman Baboosic Forested Black Forest House of Faith Souhegan Street Pond Parish Pulpit Meadow Little Baboosic Great Meadow

In addition, wetlands located within NH Public Water Supply Wellhead Protection Areas (delineated by NH Department of Environmental Services) and wetlands within the Pennichuck Brook Watershed as shown on the map dated December, 2000 shall be designated Public Water Protection Wetlands.

D. Water Resource Management Plans Alternative

The use restrictions and setbacks established in Parts A and B above are important measures intended to protect wetlands, ground water, surface water, and important wildlife resources. Part D of the ordinance is intended to provide for the development of a comprehensive plan for the protection of these resources as part of the site plan approval process in lieu of the standard requirements of the ordinance listed in Parts A and B above. Under the provisions contained in this part, the Town and landowners are offered greater flexibility in establishing effective controls through the development, implementation and maintenance of site specific Water Resource Management Plans. When meeting the criteria below, and when the owner so elects, a site-specific plan may be adopted, upon review of the Conservation Commission, Pennichuck Water Works (if required), and approval of the Planning Board, for the protection of water and wildlife resources.

The provisions of this part are applicable, for modification of or an alternative to the provisions contained in Parts A and B above, to any parcel of land to be developed or otherwise altered if one or more of the following conditions are met:

if the parcel is greater than 10 acres;
if the plan involves a subdivision of a parcel into 5 or more lots;
if the parcel contains wetlands area of greater than 2.0 contiguous acres, or;
if the parcel falls within the standard setbacks of Public Water Protection Wetlands defined in Part C above.

General Requirements

Each Water Resource Management Plan must conform to the intent of the ordinance and provide for effective, long term design and engineering controls to minimize the impacts of development and other uses adjacent to wetland areas. These plans are intended to provide for alternative controls to the setbacks and use restrictions. In no case should this section be interpreted to allow wetland degradation.

• Mitigation plans are to incorporate controls that achieve a “best available technology” (BAT’S) standard for engineering design.
• As a minimum, site activities and uses are to reflect applicable Best Management Practices as issued by the New Hampshire Department of Environmental Services or other state agency.
• Plans must incorporate documentation of all monitoring, maintenance and reporting provisions and procedures as well as any needed legal provisions to ensure future compliance with the plans.
• A minimum 25 ft. undisturbed, naturally vegetated buffer shall be established under a Water Resource Management Plan for all Public Water Protection Wetlands. The extent of the buffers must reflect the nature and value of the resources to be protected as defined in 4:11.2.
• Building setbacks from the edge of the wetland may vary but in no case shall the setbacks be less than 50 feet.
• Plans for any residential development that contain more than 2.0 acres of Public Water Protection Wetlands, or a commercial or industrial development should include surface and groundwater monitoring implementation methods and timetables. In addition to hazardous chemicals stored or used on the site, monitoring should include nutrients contributed by fertilizer applications, pesticides and herbicides of concern, chlorides, coliform bacteria and BOD. A program for reporting baseline and periodic testing for at least two years is required.

Water Resource Management Plan Requirements

A minimum of forty-five (45) days prior to submission to the Amherst Planning Board, each Water Resource Management Plan shall be presented to the Amherst Conservation Commission for review, and also to Pennichuck Water Works for review if the parcel is within the Pennichuck Brook watershed.

Each Water Resource Management Plan submitted to the Planning Board for review shall contain the following provisions:

• Identification of the risks to water resources from the proposed site activities or development and site specific restrictions to eliminate or control uses and activities that produce impacts;
• Identification of ecologically sensitive areas and features, including but not limited to, water supplies and water resources, wildlife and wildlife habitats or other resources within the influence of the site that warrant high levels of protection;
• Site design and engineering controls to minimize both on-site and off-site (within 500 ft.) impacts to water resources;
• Storm water provisions shall include at a minimum:
  • Post development storm water peak (for 10-year storm) must be less than or equal to predevelopment storm water peak.
  • Post development infiltration (2-year storm) must be greater than or equal to predevelopment storm water peak.
  • Storm water facilities must have a solids removal area that is independent of infiltrative area. Solids removal area must be easily cleaned. Storm water facilities must be designed for grease and oil removal (either mechanical or biological with plants);
• A letter from the New Hampshire Natural Heritage Inventory containing information on any rare or endangered species within the project area, or within 500 ft. of the nearest wetland/buffer impact site, whichever is furthest;
• Written provisions for the protection of any rare or endangered species as referenced above or known by the Conservation Commission;
• Provisions for the protection of the ecologically sensitive areas and features of the site;
• Building and storage area design to prevent releases or spills of hazardous materials;
• Prohibitions on the use of lawn chemicals or implementation of an integrated pest management plan to govern the use of lawn chemicals;
• Prohibition on the use of salt for winter road and parking lot maintenance and sedimentation controls for winter sand use;
• Provisions for periodic groundwater monitoring and reporting, if required;
• Provisions for periodic surface water monitoring and reporting, if required;
• A plan showing the edge of wetlands within 500 ft. of the nearest impact area, and all setback/buffer areas for any Public Water Protection Wetland;
• Provisions for future maintenance of the engineering design, operating and monitoring controls to be implemented;
• A copy of the Pennichuck Water Works review report, if received.
• A copy of the Amherst Conservation Commission review report.

ADD TO IX DEFINITIONS

Buffer An upland area immediately adjacent to a jurisdictional wetland or body of water, usually specified by a setback distance from the edge, that serves to filter surface water flowing into the wetland or body of water.

Minimal Impact Crossing Minimal impact means the least environmentally damaging practicable alternative.

Public Water Protection Wetlands Wetlands identified in Section 4-11 for their critical role in protecting water supplies.

Water Resource Management Plan A written plan containing maps, base line data, and provisions for the protection of surface water, ground water and important wildlife resources associated with a development project.