By Harry Kane

Why remove water chestnuts from the Mystic River, you may ask? Patrick Herron, Water Quality Monitoring Director for (MyRWA) Mystic River Watershed, explained that these invasive plants clog the Mystic River. The organized removal of water chestnuts allows for the native ecosystem to continue. Otherwise the water chestnut plants (Trapa Natans) will displace and kill the native species.

“The plants are spreading at a rate of 20% a year. So if there’s ten acres now it means there are twelve acres next year if we don’t do anything. At the same time, these plants are difficult because each plant approximately produces 10 seeds and they end up leaving seed banks on the bottom that can last for 15 years,” Herron explained.

This year the MyRWA has held 4 hand-pulling events. “Typically, we haul up the whole plant with the roots but that gets really cumbersome, and they get all knotted together. So we are trying a new technique, which is snipping the roots from the top of the plant using scissors,” said Beth (Meserve) MacBlane, the outreach coordinator for MyRWA.

“It’s going to take a measured approach, foot by foot working our way down the river to remove these plants,” Herron said. Usually 40-50 people attend these events.  People go out in canoes or bring their own kayaks. Many of the volunteers who participate do it because they feel it’s important to preserve the river. Resident Alicia Byrd is a Somerville supporter who does it for the fun of it. She said, “I even pay for the privilege.”

John Reinhardt, MyRWA Board President said, “this has been an incredible way for people to do something. They get dirty, smelly, and it’s a lot of work but they are smiling and happy with it.” One of the reasons that the river is dirty is due to raw sewage. When there’s a lot of rain the towns along the river may be overwhelmed and the sewage pipes overflow into the river. “Part of the problem here are the nutrients are out of balance and that’s one of the reasons the plants are going wild,” Reinhardt contended.

“Friends of the mystic river have been out here for a number of years pulling water chestnuts. Two years ago we collaborated with Groundwork Somerville and submitted for a grant opportunity. For the last two years we’ve been using those funds to work on removing water chestnuts using both mechanical harvesting as well as hand pulling events that involve the public,” Herron said.

For more information visit http://www.mysticriver.org/.

~Video by Harry Kane