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Ask the Conservation Commission, Wetlands FAQ

Sal A Mander

Professor Sal A. Mander answers questions about wetlands.

Do you need to file with the Conservation Commission before starting your dream project?  Here are answers to that and other common questions we get at the Conservation Commission office.

The general rule is that if you are planning a new well, septic system upgrade, addition, landscaping that involves heavy machinery or any other building projects near a wetland, swamp, marsh, bog,  pond, lake, river or stream you may need to file for a permit with the Conservation Commission.


Q: What is a wetland?

A: For the purposes of Massachusetts law and the Groton Bylaw, a wetland is any: lake, pond, swamp, marsh, wet meadow, floodplain, bog, river, stream, brook or vernal pool.


Q: Why are wetlands protected?

A: Wetlands perform important functions including pollution abatement, protection of groundwater (the source of many Groton residents' drinking water) , flood control, storm damage prevention and providing habitat for fish, birds, reptiles, amphibians, and other wildlife.


Q: Do I need a permit to do work near or in a wetland?

A: Yes.  Under both Massachusetts General Law Ch. 131, Sec. 40 and the Groton Wetlands Protection Bylaw, Ch. 215, of the Town code.  If you intend to do work within a wetland or the buffer zone of a wetland you must file a “Notice of Intent”(NOI) or a “Request for Determination Applicability”(RDA) with the Groton Conservation Commission prior to performing any work. If you have a small project like a deck addition, or putting in a dock, patio or pool you may be able to use the simpler and quicker RDA form. Contact the Commissions Conservation Administrator at town hall for guidance.


Q: What is a wetland buffer zone?

A: A buffer zone is the protected area surrounding wetlands which is under the jurisdiction of the Conservation Commission.  In the case of ponds, lakes, marshes, swamps, vernal pools and bogs the buffer zone is 100 feet, measured horizontally from the edge of the resource area.  Riverfront Area is defined as the area 200 feet(again measured horizontally) from the edge of the stream or river.  Floodplains do not have a buffer zone.


Q: What is an NOI?

A: A “Notice of Intent” (NOI) provides details about your proposed project, including the location and scope of work, to the Conservation Commission, the State and abutters.  It requires notification of neighbors within 300 feet, and the publication of a legal notice in the newspaper.  After the NOI is filed a public hearing is held before the Conservation Commission to gather additional information on your project.  Abutters may also comment at this time. This is the beginning of the wetlands permitting process and may require several hearings, engineered plans and other filings.


Q: Do I really need to file an NOI it sounds complicated (what is an RDA)?

A: No. If your project is small and does not require disturbance of the ground it may not.  You can file a “Request for Determination of Applicability” (RDA).  This is a simpler shorter process than an NOI (see above) allowing you to describe your project and have it reviewed by the Commission quickly, no abutter notification is required. A public notice will appear in the local newspaper.  The Conservation Commission will discuss the proposed work at a public meeting and determine if you need to file a full NOI, or if your project can proceed without an NOI.  Generally,  many residential projects, such as tree removal, decks, pools can be handled by the RDA process and are usually approved in one meeting, with a few simple conditions.


Q: I live near a mushy area where there are some ferns growing, is this a wetland?

A: Very likely, but only a soil test and examination of the vegetation can make an accurate determination.  Contact a wetland scientist or the Conservation Commission before you plan or carry out any work.


Q: I live on Lost Lake/Knops Pond and I'm planning a retaining wall; do I need to file with the Conservation Commission?

A: Yes, file an NOI if the retaining wall is located on the shore line of the Lake.  Work further away from the Lake may qualify for an RDA.


Q: I have a small lot on the lake front and I'd like add a small deck, or other feature in the lawn area. Can I do this?

A: Very likely. You must file an RDA.  If the project is in a preexisting altered area, and the Commission determines that the impact is small a permit may be issued. 


Q: I live on a lake and I would like to put a small float out on the lake for the summer?

A: If the float is bottom anchored and seasonal you do not need to file with the Commission.  However, you must receive permission from the “Harbor Master”. The Board of Selectman have designated the Chief of Police as the Harbor Master for the town. You may contact the Police at the non-emergency business phone number: 978-448-5555.


Q: I live on the lake and I would like to put up a dock; do I need to get a permit?

A: Yes, you need to at least file an RDA. In addition you will need to file with MassDEP Department of Water Resources to obtain a Chapter 91 license.  If you plan a dock that exceeds 600 square feet you will need an engineered plan prepared by a licensed professional engineer.


Q: I live near a brook and I'd like to put a new deck on the back of my house.  Do I need to file for a permit?

A: If your work is within 200 feet (measured horizontally) of a brook, river or stream you need to file with

Conservation Commission under the Wetlands Protection Act and the Groton Wetlands Bylaw.  In many cases a simple RDA may suffice.


Q: I live near a swamp and I'd like to cut down some trees near my house?

A:  Depending on the number of trees to be removed and whether you plan to remove stumps, it is likely you can file an RDA. Trees moderate the temperature of wetlands providing the ideal environment for animals that breed in and inhabit them.


Q: I'm planning on putting in a swimming pool and I see a depression fill with water near the planned location every spring; do I need to notify the Conservation Commission?

A: You should contact the Commission. It is possible what you are observing is a vernal pool.  Vernal pools usually appear in the spring,   but they may disappear for the remainder of the year.  They are important breeding habitat for salamanders, frogs, toads, and turtles.  Because of their sensitive nature vernal pools come in for special consideration under both State and local Bylaw regulations. You should definitely contact the Conservation Commission for a determination before beginning any work.


Q:  I've hired a contractor to do some excavation on my property and it's near a marshy area.  Should I contact the Conservation Commission? 

A:  Yes, you may be near a wetland, but only a soil test and identification of  vegetation can confirm this.   You are required to obtain a permit before doing any work within the 100 feet (measured horizontally) of a wetland. Don't assume your contractor knows, or will contact the Conservation Commission.  As the property owner you are legally responsible. 


Q: I suspect work is being done in a wetland buffer zone without a permit, what should I do?

A: Contact the Conservation Commission immediately, do not attempt to intervene on your own.  This may be done anonymously.  Give accurate information as to the location and nature of the work being done.  The Conservation Commission will then investigate.


Q: How do I contact the Conservation Commission?

A: Contact the Conservation Administrator at 978-448-1106, Monday-Thursday, 8:00AM to 4:00PM, Friday 8:00AM-1:00PM.

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