From the regulations promulgated July 1, 2019
A fencing solution may not be appropriate for every property. Initially, the applicant should determine the appropriate type and extent of installation for their situation. Factors to consider may include the amount of vegetation, existence of a dune currently, angle of repose, recent cutting or evidence of past bank erosion. The Conservation Commission may request an outside consultant to review this assessment at the applicant’s expense according to the Wetlands Regulations.
Any fencing activity should be viewed as a temporary measure to initially trap higher volumes of sand than American beach grass could alone. Once the beach grass is established, it has been proven to trap sand at a rate comparable to multiple sand fences. Holding a dune unnaturally seaward of the storm tide elevation at any given time creates problems for abutting properties and ultimately can negatively affect the distribution of sediment along an entire coastline alongshore, as well as on and off shore where bars provide important storm protection.
Sand fencing. Also sold as “snow fencing” in 50-foot-long rolls, 4 feet high. The rolls can be chain sawed in half to produce 100 feet of 2-foot-high fencing. Constructed of lightweight wooden slats, factory wired together with spaces between the slats approximately equal to slat width (approx. 1.5 inches). Fencing may be installed in three 10’ wide rows parallel to the shoreline, or in zig-zag pattern. Two-foot-high fencing may be installed by driving the individual slats into the sand with a rubber mallet. Four-foot-high fences may be supported by wooden posts, attached with screws or plastic ties.
Sand fencing is commonly used along the Eastern United States to encourage deposition of wind-blown sand to help re-build a dune. The effectiveness of this method in any given area depends upon availability of adequate amounts of wind-blown sand. The degree of success a fencing system will have in any given location varies along the coast line, therefore each site should be examined individually, and in conjunction with neighboring properties. The rolled sand fencing interferes less with natural processes.
Sand fencing offers a less invasive approach to dune restoration than the more substantial serpentine fence. This, when combined with a nourishment and replanting plan, will provide the coastal property owner an effective option for protecting an eroded bank or dune. The expense of sand fencing is considerably less than installing a drift fence, and its lighter construction may be less damaging to the beach during installation.
Dune restoration by means of sand fencing should take place as far landward as possible. A second or third, optional, fence may be installed up the unvegetated fore dune slope providing additional sand accumulation.
Sand fences should be made of wood slats, connected by wire and having a 50-50 ratio of open space to slats. (24” rather than 48” height will likely last longer due to less wind resistance while collecting a similar volume of sand.) The rolls should be attached to the posts with staples, with additional tie-wraps as desired. 4” x 4” rounded posts should be used if the area may be inundated with waves. Otherwise a lighter post may be used.
Posts should be set at or within several feet seaward of the toe of the dune scarp, 8’ apart. Posts should be dug five (5) to six (6) feet in the sand, and more if the fence is in a high-energy area. Each section of fencing between posts should have two removed or “missing” pickets, so as to create an opening in the fencing to accommodate birds and animals.
Every fencing project except for biomimicry shall include beach nourishment. Every Notice of Intent shall specify the amount of sand to be deposited at the site and shall identify the source from which the nourishment material will be obtained. The nourishment material must be clean sand free of debris or waste and should be of a compatible grain size to the native beach material at the site. (Note: if sand which is of smaller grain size than the native material is used, the lighter sand will wash away sooner.)
The amount of nourishment material required for each project shall be determined on a case-by-case basis and will depend upon the topography of the site and the adjacent areas. In general, it is recommended that the applicant fill the area between the fence and the dune or bank to at least one-half the fence height, or a minimum of two feet above existing grade, whichever is greater. In addition, where the distance between the fence and the mean high-water mark is fifteen feet or more, then the applicant is required to deposit sufficient material to mirror the existing beach profile.
Every fencing project shall include planting of American Beach grass between November 1 and April 1 following completion of the installation or repair of the fencing. Planting holes should be dug at least 6 inches deep, randomly spaced 10-12 inches apart. Three culms (roots) are placed in each hole and covered with sand. It is recommended to plant in the greatest density in the landward section and decrease the spacing of plants in the seaward direction. The best results have been found with two applications, one in late spring within 30 days of planting, but before April 1, and another application in late summer or early fall. For further information, see: Coastal Dune Protection and Restoration, Marine Extension Bulletin, Woods Hole Sea Grant and Cape Cod Cooperative Extension, December 2008, and Beach Nourishment, MassDEP’s Guide to Best Management Practices for Projects in Massachusetts, March 2007. Attachments
13. General Regulations applicable to all fencing projects.
a) All projects shall specify dates for commencement and completion. All projects may only begin after Columbus Day and must be completed prior to Memorial Day, provided however that the project area is clear of nesting shorebirds as confirmed by the conservation agent or her designee.
b) All construction equipment shall only access the site from the beach, and only travel along the beach below the mean high tide line. Absent a showing by clear and convincing evidence that access to the coastal bank across the applicant’s property is impossible, no sand shall be trucked or transported to the site down the beach. All sand shall be brought to the site from the top of the bank at the applicant’s property.
c) Any substantial beach restoration requiring the hauling of materials other than sand from town landings across public and private beaches will be conducted exclusively from Columbus Day to April 15th. Substantial projects are those requiring over two days to haul materials.
d) Beach construction and restoration work shall not be performed on weekends or holidays, nor before 8:00 a.m. or after 6:00 p.m on weekdays.
e) Properties between the public access point for the project and the project locus shall be considered abutters and shall be notified of any substantial beach restoration projects in the same manner and at the same time as other abutters.
f) Construction debris shall be removed at the end of each day and the access route shall be left backbladed to a normal grade.
g) Application for Construction or Maintenance of a Sand or Drift fence shall constitute agreement by the property owner to reimburse the Town for the cost of clearing away any debris generated from the property owner's fence.
h) Where fencing becomes ineffective due to storm damage, erosion or other cause, it must either be promptly repaired or removed at the property owner’s expense.
i) Where fencing does not exist on an adjacent property, the fencing erected for the applicant shall be no closer than 25 feet to the abutter’s property line; where fencing exists on adjacent properties, new fencing shall be aligned with existing fencing.
j) Owners of lots which have less than 100 feet of beach frontage may be approved for fencing construction and/or restoration projects which do not comply with these general regulations, by special permit from the Commission.
k) It is the responsibility of the project proponent to obtain consent to traverse private property as may be required by property owners.
- A well vegetated bank provides significant resistance to storm damage; therefore, the Commission requires extensive planting of the coastal bank as part of any erosion control project, including re-planting as on-going maintenance in all projects.
- In the case of an “erosion control” project permitted under these regulations, these standards must be met by a showing,by substantial evidence, that a sufficient quantity of beach nourishment and “sacrificial” sand will be provided as part of the project to ensure that the movement of sediment and sediment supply will not be adversely affected by the project.
- A model order of conditions is attached to these regulations and incorporated herein. No waivers from these required orders shall be allowed except upon clear and convincing scientific proof that the proposed waiver will improve the ability of the coastal bank to provide storm damage protection, prevent flooding and contribute sediment to the littoral system.
- Escrow agreement: Every erosion control project shall include a requirement that the property owner establish an escrow account with the Town of Truro in accordance with the requirements of the Model Escrow Agreement attached to these regulations and incorporated herein. This agreement allows the Conservation Commission to remove any project as to which the owner fails to perform ongoing maintenance as required by the Commission.