Why You Can't Put Your Grass Clippings and Leaves in Wetlands on Your Property

I have had the same conversation with people over the last few years.

Me – “You know, you cannot dump your yard waste in wetlands on your property.  You are filling wetlands and it’s against the law.”

Them – “But it’s my property. Besides, the stuff is biodegradable. What’s the harm? It’s just some grass clippings. Besides – IT’S MY PROPERTY!”

A blog posting I wrote a couple of weeks ago asked the question – “What should people be allowed to build on their property?” 

My answer was just about anything they want, as long as it complies with state laws and regulations.

Well, we have state (and local) regulations regarding the protection of wetlands, so yes it’s illegal to dump your yard waste on your wetlands on your property.  Just like it’s illegal to dump your used motor oil on your dirt behind your garage or in the storm drains in front of your house.  Although the harm from used motor oil is probably more apparent to you than grass clippings in your wetlands, the principle involved is still the same.

Used motor oil will go into the soil and eventually down to the water table where it will flow with groundwater until it discharges to the wetlands or surface water.  Used motor oil in the storm drain will get to the same place, only faster.  Most of you would be horrified to do any such thing. At least I hope so.

So why do state laws and regulations prevent you from putting grass clippings in your wetlands?

Let’s start with some of the reasoning behind the wetlands protection laws that are applicable to Westborough (the laws protect fisheries and lands containing shellfish as well). Wetlands serve a number of functions that are of interest to the entire community:

• protection of public and private water supply
• protection of ground water supply
• flood control
• storm damage prevention
• prevention of pollution
• protection of wildlife habitat

Let’s look at flood control first.  Wetlands act as a temporary reservoir for storm water.  That’s why almost all storm water systems in this town eventually discharge to wetlands.  Wetlands slow the flow of storm water and allow the waters to infiltrate into the ground, where the waters contribute to public and private water supplies.  This temporary storage of storm water serves to control flooding during storm events or times of extended rainfall.

So, when you put your yard waste into your wetlands, you are displacing the flood storage capacity of the wetlands.  Yes, the material biodegradable but the soil it eventually turns into will still be a volume of material that displaces flood water.  So if every home owner on your street puts years and years of grass clippings and leaves into the wetlands behind their house, the volumes start to become significant and the folks who will feel the impact of this practice will be the folks downstream who will be getting more stormwater coming up into their yards and into their basements which would have normally been detained in the wetlands.  Unless you live on the top of a hill (where there probably would not be wetlands anyway), you could also be the victim of the same sort of practice from your upstream neighbors.

Now, let’s look at wildlife habitat.  Wetlands provide wildlife habitat for all sorts of flora and fauna who are adapted to living in such environments.  Animals include many species of salamanders, frogs, turtles for starters.  Trees include Red Maple, Eastern Hemlock, Willow and White Cedar.  Shrubs include Silky Dogwood, Highbush Blueberry, Winterberry, Elderberry, and Northern Arrowwood.  Plants include Swamp Rose, leatherleaf, Water Lilies, and Horsetails.  The list goes on and on.  What binds most of these species together is that they need a wetlands environment to breed and in most cases, this wildlife cannot survive outside of a wetland.

The bottom line here is that if a wetland is filled – even with grass clippings and leaves, habitat for these species of plants and animals is being displaced with uplands habitat when the grass and leaves decay into soil.  Years of accumulated debris in wetlands degrades flood storage capacity of the wetlands.

So yes, it’s your property and the reasons why dumping grass clippings in wetlands is less apparent than pouring used motor oil behind your garage, but the general principle is the same.  Basically, the effects of the actions will most likely go beyond your property line.

You can still do anything you want on your property, as long as it complies with state and local laws and regulations.

Want to paint your house purple with big pink dots or fill your lawn with plastic flamingos or ceramic lawn gnomes?  Go right ahead.

Fill your wetlands – no you can’t.