Water Quality and Assessment

2016 score summary
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Overall Water Quality Grade: Fail

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To arrive at the overall grade for water quality in the Anacostia River, the Anacostia Watershed Society (AWS) first evaluates and grades each of three sections of the 9­ mile tidal river for the key indicators of Dissolved Oxygen, Fecal Bacteria, Water Clarity and Chlorophyll a. The three sections, shown on the map below, are the Maryland portion of the Anacostia (Section 1: MD Anacostia), the upper half of the Anacostia in the District of Columbia above the East Capitol Street Bridge (Section 2: Upper DC Anacostia), and the lower portion in the District (Section 3: Lower DC Anacostia). Assessment for Submerged Aquatic Vegetation (SAV), Stormwater Volume Runoff, Toxics, and Trash is conducted for the entire tidal Anacostia River. These parameters will also be taken into consideration to give %Score and Grade for each section and the entire river.

Anacostia River Section Map

Steady progress overall is seen once again for this year’s report with a small increase in the %Score. Fecal Bacteria, Water Clarity and Chlorophyll a have been slowly improving, likely a result of DC Water’s work to reduce its sewage overflows (reduced by 40% in 2009 and by 60% in 2011). Submerged Aquatic Vegetation (SAV) seems to be making a strong comeback after a decade of absence. The %Score for SAV increased by six times from last year’s report! However, these gains are not enough to result in the substantial improvement of water quality in any section or overall largely because of unfavorable weather patterns that impact parameters. With each section for various parameters continuing to earn a failing grade, our overall assessment of water quality in the Anacostia River evaluated in 2016 is an F.

An encouraging and noteworthy sign for the river has been the discovery of bivalve mollusks. It has been thought that the Anacostia is too cloudy with small particles of sediment for bivalves or other filter feeders to exist because these particles accumulate inside the organisms hindering their ability to function properly. In recent years, however, AWS staff have been seeing Asiatic clams populating the river gradually. Our Water Quality Specialist was taking photos of seagulls near the CSX railroad bridge in 2013 and found that the birds were eating clams. Though Asiatic clams are non­native, we need these types of filter organisms to help clean up the river.

Seagull with a clam in its beak

In the same year, our Conservation Biologist reported that a mussel called the Eastern floater was caught at Bladensburg Waterfront Park. These findings inspired us to conduct a mussel survey. We partnered with the Maryland Department of Natural Resources (DNR) and released the report in February 2016. AWS and DNR observed six species of freshwater mussels (Eastern floater, Eastern elliptio, Paper pondshell, Eastern pondmussel, Tidewater mucket, and Alewife floater) in Kingman Lake and along its shoreline at low tide.

We are excited to see bivale and SAV species return because it is a good indication that conditions are improving, in sync with what we are observing in terms of water quality.

Comparison to Last Year

There are limitations when comparing water quality scores over a short period of time because of numerous variables that impact water quality parameters. For example, more intense and frequent precipitation patterns generally make the water quality worse. More rain results in more sewer overflows and an increase in polluted runoff from streets and parking lots. So the comparison of indicators for wet and dry years can mask the underlying conditions. Long term trends are generally more helpful for understanding the river and changes in water quality than year­to­year, short term comparisons.

These effects appear to be at play here for dissolved oxygen (DO). Intense rain events during the grading period resulted in regular sewage and runoff discharges to the lower river from the District’s Combined Sewer Overflow (CSO) system (see Precipitation Pattern for detail). CSOs discharge a lot of organic matter that will later decompose, consuming oxygen in the water. As a result, dissolved oxygen values were very low in the District portion of the river. The faster flowing, more turbulent, Maryland streams carry more DO, enough that Maryland’s tidal river had enough dissolved oxygen to earn a B­ for the period. In contrast, the tidal river in Maryland has higher readings of fecal bacteria (thus a lower score) than the lower portions in the District due in part to the presence of more wildlife feces upriver. Potomac River water that enters the lower Anacostia as part of the daily tide cycle also has a stronger dilution effect in the lower river which could be a factor here.

Despite the frequent and intense rainfall events that brought more sediment to the river, water clarity became only slightly worse in terms of %Score compared to the past 2 years while the long­term trend shows improvement (See Parameter Trend Analysis). The long­term improving trend toward clearer water was also seen in the return of submerged aquatic vegetation (SAV) as reported in the 2015 Report Card for the first time since it disappeared from the Anacostia in 2003. SAV is back and continues to grow!

The improvement in Chlorophyll a is another indicator that the water is becoming clearer. Some of this may be a result of earlier improvements to the CSO system that have reduced the number of smaller and more frequent releases to the river resulting in more of the dirtier “first flush” runoff from the District being diverted to the Blue Plains Plant for treatment. The reduction of nutrient inputs to the river from these system upgrades (60% improvement to date) may be an important factor in the improvement of Chlorophyll a and water clarity.

While there has been substantial progress in the study and assessment of legacy toxics in and along the river, notably the ongoing investigation of toxic river sediments throughout the entire tidal portion of the river, and continued collaboration and discussions among stakeholders and potentially responsible parties, little actual cleanup has yet to occur. The only sites along the river that have completed cleanups are Washington Gas and the Washington Navy Yard, but these were on land only while river portions continue to be studied. Until there is a reduction in the presence of toxic substances in and along the river that results in an improvement in water quality and the health of aquatic organisms, this grade will remain low.

Progress on trash reduction has been slow, but growing. Past efforts to install trash traps in the District and charge fees on plastic bags in DC and Montgomery County are notable. Stepped up efforts by local jurisdictions to reach goals set in trash reduction plans required by federal law (due to the extreme nature of the problem here) should soon produce more substantial results. This includes new laws to prohibit the use of plastic foam (a.k.a. Styrofoam) as food and beverage containers (effective January 1, 2016 in the District and Montgomery County, and July 1, 2016 in Prince George’s County). The proliferation of beverage containers in river trash is a major problem yet to be addressed. Environmental advocates have started to take action to reduce beverage containers through legislation; however, these efforts have been unsuccessful thus far. Non- floatable trash is also a significant problem; AWS trash monitoring at Nash Run shows 70% of trash by count is non­floatable. More work needs to be done to address this larger problem likely through enforcement of illegal dumping and littering.

Overall Effort and Commitment Grade: C+

While water quality in the river is still failing, there has been real improvement in the overall effort and commitment of area jurisdictions for the work necessary to clean the river. Strong, committed leadership across the watershed continues to grow. Important policies to reduce pollution at its source are being passed and/or raising more awareness. Funds continue to be directed to support efforts to reduce polluted runoff by local jurisdictions. A unique public private partnership is taking hold in Prince George’s County with the intention to rapidly accelerate the use of green solutions and create local jobs to reduce polluted runoff from thousands of acres of untreated parking lots, pavement, and rooftops.

In addition to the extensive mapping and study of toxic hotspots along the river that will be used to plan the cleanup of numerous individual sites, agency officials and community leaders have been convened by the District to improve and support a comprehensive cleanup plan of contaminated river sediments.

While these many initiatives have great promise, additional efforts are required to reduce river trash, establish land development policies that aim to improve or positively contribute to river health, fully identify upstream sources of toxic pollution and their treatment, and restore headwater streams damaged by intense runoff. The uneven nature of state, federal and private sector efforts must be substantially improved and accelerated or a whole new generation will be deprived of their right to grow up along a clean and healthy river, with fish safe to eat and waters fit for swimming.

But When?

The Anacostia Watershed Society is committed to collaborating with any and all to provide the residents and visitors to the Nation’s Capital a healthy Anacostia River by 2025. Our future evaluations and report cards will show just how well our public and private institutions are performing the work necessary for these waters to meet the meaningful and understandable standard of fishable and swimmable that became federal law when the Clean Water Act was passed here in the District 44 years ago, in this very watershed.

Continue to Parameter Trend Analysis


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