A new report says some levels of pollution are down in the Potomac River, but cautioned that the once-troubled waterway isn’t out the woods yet.
Metropolitan Washington Council of Governments analyzed data collected between 1985 and 2016 and found that “water quality improvements have reduced pollution significantly.”
MWCOG’s 27-page report said two substances in particular have noticeably decreased: nitrogen and phosphorus.
Both are common nutrients for soil and water, but runoff from farms and waste treatment facilities can lead to excess amounts flowing into waterways. When too much nitrogen enters a river it can cause plants to overgrow and choke the oxygen from the water, killing fish and in some cases making the water toxic to young children.
Too much phosphorus causes algae blooms that are deadly to fish. Blooms have been spotted north of Chain Bridge, according to the report.
MWCOG’s report released on Wednesday said its pollution analysis found that:
The amounts of nitrogen and phosphorus — which, in excess, contribute to water quality problems — contained in the discharge from wastewater plants in metropolitan Washington has declined dramatically since the 1980s and is on track for further reductions. The number and extent of harmful algal blooms in the upper Potomac estuary has declined significantly. Populations of aquatic plants and animals that live in this portion of the river, such as submerged aquatic vegetation, some fish, and some waterfowl have grown closer to their historical abundances.
“Scientists are still interpreting how much time elapses between various nutrient reduction efforts and when their impact shows up in the Potomac estuary and the [Chesapeake] Bay,” the report notes. “What is certain is that additional efforts to reduce nutrients and sediment from agriculture and urban runoff will be needed to achieve the river’s long-term water quality goals.”
The report says local governments are working to reduce other contaminants like mercury, prescription drugs, and chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs).
Last year, Potomac Conservancy, an advocacy nonprofit, gave the river a “B” rating. That’s a big improvement from the “D” rating the group gave it 10 years ago.
Potomac Conservancy noted that with less pollution people are increasingly using the river “as a place to hangout, recreate and live.”
In the future, citizen scientists are likely to be a part of making these reports happen. Last month, people volunteered to start collecting weekly water samples of the Potomac and the Anacostia so scientists can track E. coli levels in both rivers.
Local governments have spent billions over the last three decades to clean up the rivers, mainly by redirecting sewage flows, and managing stormwater runoff better.
In Arlington, volunteers have cleaned up trash along streams and riverbanks for three decades.
Image (top) via Flickr pool user Wolfkann, chart (middle) via MWCOG
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(This Community Post was written by Signature Theatre and underwritten by Embracing Arlington Arts.)
Signature Theatre just released single tickets for all 33rd season productions, which highlights the organization’s long-time relationship with legendary composer Stephen Sondheim. Beginning with the musical adaptation of The Color Purple and irreverent No Place to Go, the season continues with three Sondheim musicals, the DC premieres of Off-Broadway hit Which Way to the Stage and Pulitzer Prize finalist Selling Kabul, the Tony Award®-winning rock musical Passing Strange, and return of Signature’s cabaret series honoring legendary artists.
“Last November, the world lost an icon. The death of Stephen Sondheim was a blow to everyone in the theater community. Signature Theatre would not be the same without Sondheim — he IS Signature’s ‘signature.’ This season, we are honoring the legend with productions of Into the Woods, Pacific Overtures and Sweeney Todd dedicated to his memory. These shows represent the diversity and range of Sondheim,” said Signature’s Artistic Director Matthew Gardiner about the new season.
MEGA Wine Tasting
Join us Sunday, Aug 28 from 12-3pm for our MEGA Wine Tasting
How it Works:
We’ve invited all our wine vendors that we work with to bring 6-10 wines in their portfolio (wines that are usually not carried at Osteria
Running & Strength Training Group Workout #1
Join our first workout of Coach Kate’s fall Running & Strength Training Program on Tuesday, August 30 at 6:30 a.m. at Oak Grove Park.
First/trial session is Free Of Charge. If you would like to join the program — which