Monthly e-news from Charles River Watershed Association, an internationally-recognized leader in sustainable river management. Learn more at .  
Around the Watershed
Eradicating Invasive Water Chestnuts
This past summer 300 volunteers spent 900 hours hand-pulling invasive plants through our Canoeing for Clean Water program, removing a total of 8.7 tons of water chestnuts! The primary goal of this program is to improve habitat in the Charles River Lakes District by eradicating water chestnut ( Trapa natans ). These invasive plants have been infesting this area of the river for decades because high nutrient levels and a lack of natural predators allows them to grow prolifically. The plants degrade water quality and disrupt recreation. For the past 12 years a combined effort of hand-pulling and mechanical harvesting, funded by the Massachusetts Department of Conservation and Recreation (DCR), has been moving us closer to reaching our goal. CRWA determined there was a 12% decrease of water chestnut coverage from last year to this year even before pulling began! This year, volunteers cleared approximately 32 acres of water chestnut, and today nearly no plants remain.

This program raises awareness about the infestation of invasive plants and creates new river stewards. A big thanks to all our volunteers and to our Invasive Plant Removal Volunteer Coordinator, Catie Colliton, for educating and leading volunteers in protecting and preserving our beloved river. Learn more about the threat water chestnuts pose to ecosystems and how you can get involved in our program next year.
Live Alerts from the Charles River
Did you know CRWA provides a daily water quality forecast for the Charles River Lower Basin all summer long? The Charles River Basin is one of the most heavily used recreational areas in the country; however, there are still pollution sources that impair safe recreation on certain days. If you are subscribed to our water quality notification email alerts , you’ve probably noticed we’ve been experiencing many red flags lately. Red flags indicate poor water quality and alert boaters that they may want to take certain precautions. Here are the main causes of “red flag days” and how we’re working to eliminate them:

  • Stormwater runoff: Stormwater runoff is rainwater that falls on buildings, pavement, or lawns and flows across these surfaces into nearby streams, storm drains, and rivers. As water flows across these impervious surfaces it collects pollutants, such as sediment, bacteria, and nutrients, that are then deposited into local waterways. In the summertime, runoff also heats up as it moves across hot pavement, increasing temperature in local water bodies which harms fish and other aquatic life. Fast-moving runoff can cause erosion of stream banks or other areas depositing sediment into our rivers. A great way to manage stormwater runoff is with green infrastructure which naturally filters pollution. Stormwater runoff pollution is the most common cause of red flags, which typically last 24-48 hours following rainfall events large enough to produce runoff. This season has had 10 “red flag days” related to stormwater pollution. Our Blue Cities work addresses this head on.

  • Combined sewer overflow (CSO): We still have places along the river where raw or partially treated sewage is released into the river during heavy rain events, to avoid sewage from overflowing into homes and streets when the collection pipes are full. CSOs occur in very heavy or intense rain storms. CRWA has been notified of 3 CSOs in the Lower Charles since July, each causing 48 hours of red flag conditions. Climate change is bringing an increased amount of heavy rain storms; locally, these storms have increased 70% since 1958, which is almost double the increases observed elsewhere in the United States. CSOs are unacceptable and a huge risk to river health, public safety, and economic growth. We need to address this issue before it‘s too late, and that starts with public notification of CSO releases. CRWA is fighting for this now.

  • Toxic algal blooms: Cyanobacteria, or blue-green algae, can release toxins into the water that can be harmful to people and pets. Cyanobacteria blooms (large amounts of cyanobacteria growing in the river at the same time) are spurred on by warm water and high nutrient concentrations, caused by stormwater runoff. The Charles River typically experiences one bloom each summer, lasting at least two weeks, causing red flags in the affected areas. The cyanobacteria bloom on the Charles in late July lasted 15 days and received significant news coverage. With climate change, we expect these blooms to persist or worsen over the years. But the good news is that there are steps we can take to prevent this: the greatest being to treat stormwater pollution before it reaches the Charles.
Bugging Out on the Charles
CRWA and a number of lucky volunteers have spent the summer looking for benthic macroinvertebrates (BMIs) in the Charles! These small aquatic animals and larval insects are often used as indicators of the health of a waterbody, as some species are more tolerant of pollution than others. Generally, a healthy stream will support an abundance and diversity of BMIs. BMI sampling offers an integrated way of understanding water quality in streams, in addition to testing water chemistry. We often turn to BMI sampling when considering restoration projects, and train volunteers each summer to conduct their own BMI sampling at selected sites to buttress our water quality data.
Launching the Herter Park GI Laboratory
With support from the BSA Foundation and the Harvard Allston Partnership Grant, CRWA launched the Herter Park GI laboratory in spring of 2019. In partnership with the Friends of Herter Park and Charles River Conservancy, this project has helped create an opportunity to engage the residents of Allston-Brighton (including local middle school students) with CRWA field science and stewardship efforts at Herter Park. The residents of north Allston-Brighton have been learning about green infrastructure and as a result become informed stewards of Herter Park and the Charles River. Swing by Herter Park on Saturday, September 21 for the 16th Annual Revels RiverSing . We’ll be there to take you on a tour!
Join Us
Honoring Champions of the Charles

This year, CRWA is honoring Boston City Councilor Michelle Wu , for her tireless advocacy and leadership on climate change, and WBUR Earthwhile for its dedication to sound environmental reporting. You won’t want to miss this memorable night under the Washburn Pavilion Tent at the Museum of Science on Thursday, September 19 at 6:30 pm. Buy your tickets here!
Exploring Riverside
Join Historic Newton and Newton Conservators for a Riverside Trail Walk, which will follow old pathways to breaktaking stops along the Charles River. The walk will explore sites of canoeing activity from the early 20th century and look at the proposed new Riverside Trail System. To learn more about the route and pre-register, click here .
Intern Spotlight
Meet our GIS and Watershed Science Fall Interns!

Upcoming Events
Champions of the Charles Gala | Thursday, September 19 at 6:30 p.m.
Please join us for a magical night under the Washburn Pavilion tent at the Museum of Science to advance our mission of protecting and restoring the Charles River. We look forward to honoring  Boston City Councilor Michelle Wu  for her tireless advocacy to make Boston a leader on climate change, and  WBUR  for their dedication to sound environmental reporting. Learn more.

Nature Walk & Climate Cafe | Tuesday, September 24 at 6:00 p.m.
Enjoy an early evening nature walk through the Broadmoor Wildlife Sanctuary with Elissa Landre, Director of Broadmoor Wildlife Sanctuary, from 6-7 pm on Tuesday, September 24. Immediately following the walk from 7:30–8:30 pm, we’ll move indoors to the Lookout Taproom at Belkin Family Lookout Farm for an open discussion. Learn m ore.

A Watershed Moment | Thursday, September 26 at 1:30 p.m.
On September 26, the 2019 Rhode Island Infrastructure Summit features a breakout session entitled, "A Watershed Moment: Managing Stormwater at the Regional Scale" with panelist CRWA Director of Watershed Resilience, Pallavi Kalia Mande. The panel will  feature case studies about how to implement regional stormwater projects and programs.   Learn more .

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