Water Blog - How Healthy is our Harbor?

News, notes and thoughts from Blue Water Baltimore.



How Healthy is our Harbor?

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Today, Blue Water Baltimore and Waterfront Partnership of Baltimore released the annual Healthy Harbor Report Card, which examines the Baltimore region’s water quality, and how it impacts ecological and human health parameters.

The report card is based on our Baltimore Harbor Waterkeeper’s robust monitoring program. Our staff scientists work with dedicated volunteers to monitor a total of 49 stations in the Jones Falls and Gwynns Falls watersheds, as well as the tidal Patapsco River and its tributaries for several parameters that help us determine the overall health of our waterways. All of our data is recorded each week on our HarborAlert.org website.

Overall, our 2016 data indicates failing grades throughout the Patapsco River watershed due to stormwater pollution problems. But we have to look deeper for a more complete picture. In some areas we saw improvements to the bacteria scores, which is promising. However, we had less rainfall in 2016 than we did in 2015 and less rain equates to fewer sewage overflows and less polluted stormwater runoff, which can lead to improved bacteria scores.

Two important indicators for our water health are nutrient pollution and conductivity — the amount of salts and chemicals in the water. Many of our stream-health parameters are in the healthy range, but we’ll continue to see failing grades until the level of conductivity declines. As stormwater runoff carries salts and other pollutants into our streams, conductivity scores drag down our stream grades by making the water unsafe for fish and other wildlife. Nitrogen and Phosphorous pollution feed algae blooms in the Harbor, which can ultimately lead to dead zones and fish kills. Our results demonstrate high chlorophyll levels throughout the entire sampling season, which indicates the presence of algae blooms. As we strive towards cleaner water, fixing our pipe infrastructure and reducing stormwater runoff should be our top priorities.

For more information including stories of water improvement efforts around the city, check out the 2016 Healthy Harbor Report Card and see below for more information about what each water quality indicator means.

What Do the Water Quality Indicators Mean?

Fecal Bacteria is a human health indicator. Bacteria measurements help us determine the risk of getting sick if someone comes into contact with the water. Some common sources of bacteria are sewage overflows, broken sewer pipes, and pet waste.

Chlorophyll tells us if there is too much algae in the water.  Algae blooms are fed by excessive nutrients in stormwater runoff and sewage overflows.  Too much algae can lead to low dissolved oxygen, which can ultimately cause fish kills.

Conductivity tells us if there are too many salts and chemicals in the streams that could harm fish and other organisms. Polluted stormwater runoff carries salts and other pollutants into our streams.

Dissolved Oxygen is important for all organisms that live in the water.  Decaying algae blooms can deplete the oxygen in the water, which can cause fish and shellfish to suffocate.

Total Nitrogen and Total Phosphorus are nutrients that tell us how much sewage and stormwater pollution are coming from the land. Some common sources of nutrient pollution are fertilizers, waste water, urban runoff, and the burning of fossil fuels.

Turbidity and Water Clarity are important for fish and plants in the water. The water should be clear so that sunlight can reach underwater plants, and so that fish can see their prey. Sediment carried by untreated stormwater runoff makes our streams and rivers cloudy.