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A Blue View: Grading the Inner Harbor's Health

On the surface, the recently released 2014 Healthy Harbor Report Card may paint a bleak picture of our local waterways, but a closer analysis reveals a few reasons for hope. 

Published June 09, 2015

An initiative of the Waterfront Partnership of Baltimore, the Healthy Harbor Report Card tracks the progress being made toward a swimmable, fishable future for our Inner Harbor. While Baltimore’s streams, rivers and harbor received dismal scores between 52 percent and 61 percent, some of these grades indicate improvements over the previous year. Gwynns Falls’ overall score, for example, improved from an F to a D- since 2013.

To fully understand these signs of progress, you also have to understand what the report card is measuring. Waterfront Partnership of Baltimore uses six major water-quality indicators to determine scores:

Fecal Bacteria Levels

These numbers help to determine the risk of getting sick from contact with water. Sewage overflows, broken sewer pipes and pet waste contribute to high fecal bacteria levels.

Chlorophyll A

Chlorophyll a tells us if the water contains an unhealthy amount of algae, which can lead to low dissolved oxygen and harm fish and other living things. 

Chlorophyll levels improved in the Tidal Patapsco River, earning a D- compared to last year’s F. 


By measuring conductivity, we can find out if there are too many salts and chemicals that could harm fish and other organisms. Common sources of conductivity pollutants include road salt, wastewater and industrial discharge.

Dissolved Oxygen

This is an important factor to measure since it’s necessary for all harbor inhabitants to breathe. 

Dissolved oxygen improved in the Inner Harbor, earning a C- compared to last year’s B-.

Total Nitrogen and Phosphorus

These are nutrients that tell us how much stormwater pollution is being washed off the land into the water. Common sources include fertilizers, wastewater, urban runoff and the burning of fossil fuels. 

Total nitrogen improved form an F to a D in Baltimore streams. Total phosphorus improved from a C to a C+ in Baltimore streams.

Turbidity and Clarity

This indicator tells us if the water is clear enough for fish to find their prey and for underwater plants to thrive. 

In order to continue moving in the right direction for a healthy harbor, it’s critical for individuals and communities to be cognizant of their impact on our waterways. We can help the harbor by properly disposing of trash and recycling, reducing stormwater runoff and picking up pet waste. 

To see the full report, click here.

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