Floating Wetlands

Learn more about the Charles River Floating Wetland with a short introductory video.

The Charles River Floating Wetland explores an ecological intervention to reduce harmful algal blooms in the Charles, which threaten the river’s health and limit the feasibility of swimming. Reducing nutrient pollution remains a vital method for preventing blooms, but this approach depends on increasingly complex solutions. Ecological interventions, like the floating wetland, offer an alternative and complementary strategy. Experiments have shown that for water bodies like the Charles, algal blooms can be understood as a symptom of a broken food chain. Our project aims to strengthen the missing link–zooplankton populations–by providing additional wetland habitat.

We are continuing a multi-year partnership with Northeastern PhD student Max Rome on the research program, are grateful for the in-kind engineering services provided by Foth, and have collaborated with interpretative materials professional Penelope Taylor on engagement and signage. In partnership with MassDCR, we have installed a floating wetland in the Charles River in Cambridge downriver of the Longfellow Bridge. During the island’s two year installation, a Northeastern research group will collect data to understand if adding additional habitat has the hypothesized outcome on the local food chain. The CRC will use the wetland to help the public understand the ecology of the river and ways that we can help make it a healthy and vibrant ecosystem.

Check out the project’s Storyboard for additional information and go in-depth with the science behind the initiative on the project’s research website.


The floating wetland is located in the Charles River along Cambridge Parkway, just downriver of the Longfellow Bridge near the mouth of the Broad Canal.

The Floating Wetland with the Cambridge Parkway in the background.
The Floating Wetland with the Longfellow Bridge in the background.


  • Heather and Robert Keane Family Foundation
  • The Boston Foundation
  • Foth
  • The Sasaki Foundation
  • Carol and Paul Fremont-Smith
  • BioMatrix Water
  • BSA Foundation

Interested in supporting our Charles River Floating Wetland project? Contact Laura Jasinski, ljasinski@thecharles.org.


  1. design, permit, and install a floating wetland to demonstrate the importance (and absence) of shoreline vegetation
  2. research the impact on local zooplankton populations and quantify the scale at which water quality could be affected and improved
  3. engage the public on the river’s health
Rendering of floating wetland design by Sasaki.


This project kicked off in the Fall of 2018. Since then, the team has:

  • completed a 9-month residency at the Incubator at Sasaki (check out our chapter of the Sasaki Foundation 2018-2019 Design Grant Research publication)
  • determined an optimal modular product for our purposes, manufactured by Biomatrix Water, a leader in the Living Waters Cities movement
  • partnered with an experienced marine engineer, Foth, on the anchoring and installation
  • navigated the complex permitting process that included an Order of Conditions from the Cambridge Conservation Commission, Construction Access and Research permits from MassDCR, a Chapter 91 permit from MassDEP, and submission to the Army Corps.
  • assembled the floating matrix, planted it with 19 species, and installed it into the Charles River
  • partnered with Northeastern University on their detailed two-year research program that will study the impacts the wetland has on the local ecology


Because public engagement is central to the mission and success of the project, we have taken several opportunities to talk to the community, including two Cambridge Science Festival events, as well as the Kendall Square Challenge and Cambridge Arts River Festival, for which we developed interactive games to demonstrate the ecological concepts. Now that the wetland is installed, we are developing additional engagement opportunities, currently centered around virtual opportunities. Stay tuned for updates on our website as well as on Facebook, Twitter, and Instagram.

“Floating Wetland” card game at the Cambridge Arts River Festival!
“Floating Wetland” tag at the Kendall Square Challenge.

Have a question or want to learn more? Contact Vanessa Nason, vnason@thecharles.org.

Lead image by Sasaki and the Sasaki Foundation.