Goals and Policies
2.3.1 Goal: to preserve and restore the quality and quantity of inland and coastal wetlands on Cape Cod.
Minimum Performance Standards
2.3.1.1 The Dennis Conservation Commission shall not permit wetland alteration except as provided herein. As an exception, where there is no feasible alternative, water-dependent projects involving wetland alteration with appropriate mitigation may be permitted subject to the approval of all permitting authorities. Such permission may be granted subject to a finding that there is no feasible alternative location for the project and that any necessary alteration is the minimum necessary to accomplish the goals of the project. Appropriate mitigation shall not include wetland creation or replication.
ACCOMPLISHMENTS: The Dennis Conservation Commission generally does not allow the alteration of wetland areas and does not allow wetland creation or replication as offsets for wetland alteration.
2.3.1.2 Vegetated, undisturbed buffer areas of at least 100’ width shall be maintained and/or provided from the edge of coastal and inland wetlands including isolated wetlands, to protect their natural functions. This policy shall not be construed to preclude pedestrian access paths, vista pruning, or construction and maintenance of water-dependent structures within the buffer area, any of which may be permitted at the discretion of permitting authorities where there is no feasible alternative to their location. The Conservation Commission shall require a larger buffer area where necessary to protect sensitive areas or where site conditions such as slopes or soils suggest that a larger buffer area is necessary to prevent any adverse impact to wetlands and associated wildlife habitat. Where a buffer area is already altered such that the required buffer cannot be provided without removal of structures and/or pavement, this requirement may be modified, provided it makes the following findings: 1) that the proposed alteration will not increase adverse impacts on the specific portion of the buffer area or associated wetland and, 2) that there is no technically demonstrated feasible construction alternative.
ACCOMPLISHMENTS: The Dennis Conservation Commission maintains jurisdiction over all lands within the 100 foot buffer area to coastal and inland wetlands. The Commission maintains a 50 foot no disturb zone surrounding all wetland resources.
2.3.1.3 Disturbance of wetlands and buffer areas for operation and maintenance of underground and overhead utility lines (electrical, communication, sewer, water, and gas lines) may occur. Installation of new utility lines through these areas may occur where the permitting authority finds that the proposed route is the best environmental alternative for locating such facilities. In all instances, disturbance of wetland and buffer areas shall be minimized and surface vegetation, topography and water flow shall be restored substantially to the original condition.
ACCOMPLISHMENTS: The Dennis Conservation Commission maintains jurisdiction over all lands within the 100 foot buffer area to coastal and inland wetlands. The Commission maintains a 50 foot no disturb zone surrounding all wetland resources.
2.3.1.4 Stormwater management plans for development shall preclude direct discharge of untreated stormwater into natural wetlands and waterbodies. New stormwater discharges shall be located a minimum of 100’ from wetlands and waterbodies.
ACCOMPLISHMENTS: The Dennis Storm Water Management By-law prohibits discharges within 100 feet of wetlands and water bodies.
Other Development Review Policies
2.3.1.5 Measures to restore altered or degraded inland and coastal wetlands, including nonstructural bank stabilization, revegetation, and restoration of tidal flushing should be encouraged. However, such areas should not be used as mitigation for wetland alteration projects (mitigation banking).
ACCOMPLISHMENTS: The Dennis Engineering and Natural Resources Departments have overseen projects to re-vegetate dunes, stabilize banks and restore tidal flushing. These projects have included the Bridge Street Culvert replacement which restored tidal flushing along Sesuit Creek allowing saltwater to halt non-native species intrusion into the Sesuit Creek Salt Marsh.
2.3.1.6 Construction of artificial wetlands for stormwater and wastewater management may be permitted in appropriate areas where there will be no adverse impact on natural wetlands, waterways and ground water.
ACCOMPLISHMENTS: The Dennis Storm Water Management By-law includes provisions for the use of storm water swales and ponds to control the rate and volume of storm water run-off.
2.3.1.6 For agricultural areas in wetlands and buffer areas, management practices that would improve water quality and conserve water as recommended by the Soil Conservation Service should be encouraged.
Implementation
1. Dennis shall develop and modify it’s bylaws to protect the town’s unique resources.
ACCOMPLISHMENTS: The Dennis Conservation Commission has revised the Dennis Wetlands Regulations to protect wetland areas. In addition, as part of the Quivet Neck/Crowe’s Pasture DCPC process a special zoning by-law was created which protected sensitive wetland resources in this resource protection district.
2. Dennis shall aid County Agencies in the development and implementation of a site-specific buffer area methodology to assess additional buffer area requirements for sensitive wetlands and water bodies.
ACCOMPLISHMENTS: The Dennis Conservation Commission works with county agencies on wetland related issues.
3. Dennis shall support passage of state legislation to allow local Conservation Commissions to use revolving funds to pay consultants engaged in project review.
ACCOMPLISHMENTS: The Dennis Conservation Commission uses a revolving fund and applicant fees to engage consultants in project review.
4. Dennis shall consider mapping wetlands at a scale appropriate to local regulatory programs and should identify and wetlands so as to maintain their ability to provide natural functions.
ACCOMPLISHMENTS: The Dennis Conservation Commission requires wetlands to be mapped at a scale which is usable by the Natural Resources Department and Conservation Commission in project review.
5. Dennis shall adopt local wetlands bylaws or ordinances that provide for the following: protection of vernal pools outside other resource areas as well as isolated wetlands, a policy of no alteration/replication of wetlands for both public and private applicants, expansion of jurisdiction beyond 100 feet where appropriate, improved enforcement authority, and the ability to hire consultants to review applications at the applicant’s expense.
ACCOMPLISHMENTS: The Dennis Wetlands By-law includes protections for vernal pools and other isolated wetland resource areas.
6. Dennis’ Conservation Commissions shall work closely with the Board of Health and other relevant town boards to develop mutually acceptable policies for wetland boundary delineation. The Dennis Conservation Commission shall review the siting of new subsurface disposal systems within designated wetland resource areas and their buffers consistent with the Dennis Wetlands By-law. The Board of Health will approve new subsurface disposal systems in relation to these areas, as well as improving and retrofitting areas with failing systems.
ACCOMPLISHMENTS: The Dennis Conservation Commission and Board of Health work together on wetland delineation issues when they arise. Predominantly, the Board of Health defers to the Conservation Commission on the delineation, while both Boards work cooperatively on siting and review of new subsurface disposal facilities.
7. Dennis shall develop and implement plans to address existing stormwater management problems where runoff and drainage systems are adversely affecting water quality in wetlands and water bodies.
ACCOMPLISHMENTS: The Town of Dennis has adopted a Storm Water Management Plan and By-law addressing existing and future storm water facilities to ensure that wetlands, water bodies and groundwater is protected.
8. Dennis shall identify, certify and protect vernal pools.
ACCOMPLISHMENTS: The Dennis Conservation Commission works on identifying and certifying vernal pools.
9. Dennis shall consider a bylaw that would minimize the clearing of vegetation and alteration of natural topography, with native vegetation planted as needed to enhance or restore wildlife habitat.
ACCOMPLISHMENTS: The Town of Dennis, as part of the Quivet Neck/Crowe’s Pasture Resource Protection District has adopted restrictions on the clearing and alteration of natural topography. The by-law also includes restrictions on clearing of vegetation to protect these areas.
10. Dennis shall consider regulations that would minimize the fragmentation of wildlife and plant habitats by the establishment of greenways and wildlife corridors, as well as by the protection of large unfragmented areas, and the use of open space planning.
ACCOMPLISHMENTS: The Dennis Natural Resources Department works to create and protect greenways and wildlife corridors. In addition, the Dennis Water District, Dennis Land Acquisition Committee and now Community Preservation Act Committee have worked to protect large unfragmented areas as open space.
11. Dennis shall consider the prohibition of development within a minimum 200 feet radius around vernal pools.
No progress.
12. Dennis shall establish the necessary policies and/or bylaw/regulations to prohibit untreated stormwater from being discharged directly into natural wetlands and waterbodies. New stormwater discharges should be located a minimum of 100 feet from wetlands and waterbodies.
ACCOMPLISHMENTS: The Town of Dennis has adopted a Storm Water Management Plan and By-law which, among many things, prohibits storm water discharges within 100 feet of wetlands and water bodies.
