Waterfront Partnership report gives harbor ecological health C grade

While Baltimore's harbor remains swimmable, the waterway's health continues to be impacted by sewage overflows, stormwater runoff, and trash pollution, according to the Waterfront Partnership's annual Harbor Heartbeat report card released on Thursday.

For the first year, the report assigned recreational and ecological health grades for sites around the harbor.

The harbor earned an overall C grade for ecological health, which Waterfront Partnership vice president Adam Lindquist said is a signifier of both the diligent improvements to the harbor's health in recent years as well as the hard work that still needs to be done.

"Baltimore Harbor is a recovering ecosystem, but it doesn't have the resilience you would like it to have," said Lindquist, who oversees the Waterfront Partnership's Healthy Harbor Initiative. "So when we have an algae bloom or low dissolved oxygen event like we did this past September, wildlife can still become stressed to the breaking point. But as we continue to improve our water quality, we will improve the resilience so that these kind of events have smaller and smaller impacts on wildlife in the harbor."

In September, Baltimore's harbor experienced a fish kill due to pistachio tides , the result of sulfur bacteria being pushed to the surface and causing smelly green algal blooms; and mahogany tides, from nitrogen and phosphorus runoff causing brown algal blooms.

Ecological health grades were fairly consistent across water testing sites, with scores ranging from C- to C.

Grades for recreational health, which measured the percentage of water samples that tested below Maryland's threshold for safe water contact for recreation purposes, varied more widely. Fort McHenry, the Mainstem Patapsco River, and Masonville Cove each earned an A+ for recreational health. Meanwhile, sites at Ferry Bar Park and the Patapsco River Mouth received F grades.

The Waterfront Partnership last year announced that Baltimore's harbor was finally healthy enough for swimming , more than a decade after the partnership launched its Healthy Harbor Initiative with the goal of making the harbor fishable and swimmable. (There are some conditions to that swimmability: swimmers should wait at least 48 hours after rainfall due to stormwater runoff; the water should be deep enough that polluted sediments will not be stirred up from where they've settled on the harbor's floor; and swimming should only take place during designated events with proper supervision to avoid injury from boat traffic and other dangers.)

In June 2024, Baltimore held the Harbor Splash , the city's first public swim event in the harbor in more than 40 years. At that event, 150 people jumped into the Inner Harbor in timed slots with groups of 25 people to celebrate the swimmability milestone. (The Inner Harbor earned a B- grade for recreational health in this year's report.)

The Harbor Splash "sold out" within 10 minutes of registration going live, and the event had a waitlist of more than 1,000 people, according to the Waterfront Partnership.

After the inaugural event garnered such enthusiasm, the Waterfront Partnership is not only bringing back Harbor Splash next year, but it is also planning other events, including a half-mile swim across the harbor and stand-up paddleboard races.

Days after this summer's Harbor Splash, ultra-distance swimmer Katie Pumphrey completed a 24-mile swim from the Chesapeake Bay Bridge to Baltimore's Harbor in about 14 hours. Pumphrey plans to repeat that swim next year.

When floated the ideas of a Baltimore Triathlon or a winter plunge, Lindquist said the possibilities are certainly open.

"I would love that," he said. "I think that that's one of the things we're hoping to see as we demonstrate that you can safely swim in the Baltimore Harbor. We would love to see an event like a triathlon come and incorporate Baltimore Harbor into its route."

Still, Lindquist acknowledges there remains more work to be done to further improve both the ecological and recreational health of the harbor.

Baltimore's googly-eyed garbage interceptor Mr. Trash Wheel was launched in 2014, and in that 10 years he has collected 5.2 million pounds of trash from the mouth of the Jones Falls stream at the Inner Harbor.

Among that heap, Mr. Trash Wheel has gathered nearly 2 million plastic bottles. The Waterfront Partnership is advocating that Maryland's legislature pass a "bottle bill" to reduce litter and pollution from plastic bottles.

"If we pass the beverage container deposit law, we can actually prevent Mr. Trash Wheel from eating his 2 millionth plastic bottle," Lindquist said.

Additionally, the Waterfront Partnership is calling for Maryland to enact the Extended Producer Responsibility Act, which would hold manufacturers responsible for their products' impact on the environment.

The Baltimore City Department of Public Works has been working to repair and upgrade parts of the city's aging sewer infrastructure. That has resulted in an 84% reduction in sewer overflows (more than 240 million gallons of sewage) into the Baltimore harbor over the last four years.

The report also acknowledged the tragic collapse of the Francis Scott Key Bridge earlier this year, in which six construction workers died.

The extent of the bridge collapse's environmental impact is not yet known, but it stirred up polluted sediment that could harm wildlife in the Chesapeake Bay.

"The collapse sent a plume of sediment into surrounding waters where it impacted aquatic life, potentially including a nearby oyster sanctuary reef [near Fort Carroll]," the report's authors write.

The Waterfront Partnership anticipates a survey of the reef's health within the next 12 months.

The good news: polluted sediment ingested by oysters in that reef will not be consumed by people because it is a no-harvest reef. The bad news: the sediment may have smothered oysters in the reef, potentially setting back restoration efforts.

The Great Baltimore Oyster Partnership supplies 350,000 new oysters to the reef at Fort Carroll annually. To offset any potential damage from the bridge collapse, they plan to increase that amount to 400,000 in 2025.