Dear Friend of the Charles River,

We hope you are finding ways to escape the summer heat!

These days especially, we are grateful to have the Charles River right in the heart of our city. The parks are some of the best places to stay cool, offering shade and pleasant river breezes. When you visit, please continue to adhere to MassDCR guidelines for safe park use.

This is our eighth Bringing the Parks to You newsletter. We hope you enjoy it!
Bringing the parks to you...
Along the Cambridge shore of the Charles River, just east of the Watertown boarder, are seven and a half acres of “urban wild,” known as Hell's Half Acre. A multi-use path, well-trafficked by walkers, joggers, and bikers, loops through the area and lines the river's edge and adjacent Greenough Boulevard. The park provides several ecological and social benefits to the surrounding community and is enjoyed by Cambridge, Watertown, and Boston residents every day. View Hell's Half Acre on a map.
As the construction of parkways advanced along both sides of the Charles River, the area of Hell's Half Acre remained one of the last undeveloped sections of the Charles River Basin well into the mid 1900s. Though treated as a dumping ground and littered with garbage, the relative wilderness appealed to local children who joyfully explored the plants and wildlife.

However, the state had longstanding plans to build a road through the area, spanning back to 1907. After the Eliot Bridge was completed in 1951, connecting Cambridge to Allston just north of Hell's Half Acre, the state revived the roadway project. Before even finalizing the design drawings, the Metropolitan District Commission (today's MassDCR) dumped gravel along the proposed route.

In famous opposition to the dumping, Bernard DeVoto, a local writer and conservationist, advocated for the preservation of Hell's Half Acre with an influential 1955 Harper's essay. Inspired by the teenage boys, including his son, who cataloged the species of the area, he argued that if re-routing the road "should cost ten or fifty times as much as taking the highway across Hell’s Half Acre, it would nevertheless be an economy — a cash and tax economy — so great that a commission endowed with proper business sense could never consider any other course." Though the road (today's Greenough Boulevard) was completed in 1966, DeVoto's essay and the resistance it helped spark marked a shift from viewing the river's wetlands and marshes as useless, to social, economic, and educational assets.

(Source & photo source:  Inventing the Charles River, by Karl Haglund, MIT Press, 2003)
Even with the construction of Greenough Boulevard, which now includes a well-traveled bike path, Hell's Half Acre has endured as an "urban wild" within the Charles River Reservation. However, it is increasingly overrun by invasive species that threaten the biodiversity and health of the ecosystem. The CRC is partnering with the Department of Conservation and Recreation (MassDCR) to conduct habitat restoration and invasive plant control. These efforts will restore native vegetation, increase wildlife habitat, and engage and educate the public.

Hell's Half Acre's diverse landscape, which features riverfront, successional upland forest, wetland, and road’s edge habitat, is a high-impact opportunity to bolster biodiversity. Native plants, unlike their non-native and invasive counterparts, have co-evolved to support a variety of other species, and their re-establishment will help sustain the biodiversity that many birds and wildlife depend on to survive. Additionally, native plant vegetation in Hell's Half Acre will improve the health of the Charles River watershed by helping absorb and filter runoff from the nearby roadways. Restoration of riparian habitat will also protect the riverbank from storm damage and erosion.

The restoration will be performed by a certified contractor and include manual invasive plant removal, targeted herbicide application, and replanting with native species. Since invasive plants and their seeds can persist beyond initial control efforts, treatment is planned for three years, and maintenance of the site will be ongoing. We will also enlist our Conservancy Volunteers, who will be trained in manual invasive plant removal and natives replanting. By involving the community, we will promote stewardship and provide valuable hands-on volunteer opportunities. If you'd like to support the restoration of Hell's Half Acre, contact
The herbicide application methods selected for Hell's Half Acre are designed to limit and contain herbicide to the stands of invasive species and the project has been carefully reviewed and permitted by MassDCR and Cambridge Conservation Commission. To confirm that the herbicide is not being transferred to the river in harmful amounts, we have also partnered with Northeastern University and Professor Loretta Hernandez to develop a monitoring plan.

Professor Hernandez and her team have deployed passive water samplers upstream and downstream of Hell's Half Acre. The samplers are designed to collect data over time and will determine if and how much of the active chemicals have been added to the Charles. The CRC does not take the use of herbicide along the Charles River lightly, but recognizes it is a necessary tool in the restoration of this important stretch of riverfront.
"As a Cambridge resident who enjoys birding, I am delighted to see invasive plants removed at Hell's Half Acre, making room for native species that will provide food and shelter for our migrant and resident birds."

Martha Stearns
Cambridge Resident

  • Bernard DeVoto's 1955 Harper's essay advocating for the preservation of Hell's Half Acre was influential in its day and marked a shift in the perception of wetlands and marshes along the Charles. Read his words: "Hell’s Half Acre, Mass."

  • Hell's Half Acre, and other natural areas around the Charles River, provide important habitat for birds, and in turn, desirable destinations for birders. Read Boston Globe reporter Billy Baker's hilarious account of participating the Mass Audubon's bird-a-thon this spring: "Competitive birding turned me into a monster."
These days, it's hard to stay cool. But the parks along the Charles River are some of the best places to beat the heat; they offer shade and cooling breezes, in addition to beautiful river views!

Since the pandemic began, we have used our social media channels to keep you connected to the parks and to each other. We hope you will join us on Instagram , Twitter , and Facebook .
We appreciate your ongoing support so that we can continue to steward the Charles River and its parks, a resource that is more important than ever.