In 2018, Hamlin Street NE installed bioretention systems managing 2.6 acres in Washington, DC. 8 years later, they retain nearly 20,000 gallons per storm, improving water quality in Hickey Run

Hamlin Street bioretention systems are giving stormwater somewhere else to go. Two systems along the Washington, DC, street can retain nearly 20,000 gallons during a storm. That is a significant amount of water for a project built within an ordinary urban neighborhood. The systems also sit within the Hickey Run watershed, where controlling polluted runoff matters for local water quality.

The project manages runoff from roughly 2.75 acres around Hamlin Street NE. Much of that area includes hard surfaces that prevent rain from soaking naturally into the ground. Instead, rainfall can move quickly across streets and other paved areas toward drainage infrastructure. The bioretention systems interrupt that rush and hold water long enough for treatment.

There is also an important detail behind the project's timeline. Hamlin Street was identified for stormwater improvements around 2018, but construction came later. Work began in 2022, and the project was completed during fiscal year 2023. The finished systems now provide roughly 2,627 cubic feet of stormwater retention per storm event.

Why does this part of Washington need stormwater control?

Urban rain behaves differently from rainfall falling on open soil. Roads, sidewalks and other hard surfaces leave water with fewer places to disappear naturally. During heavier storms, runoff can therefore build quickly and carry material from developed areas into nearby waterways.

Hamlin Street sits within the Hickey Run watershed, making that runoff especially relevant. Hickey Run is part of the wider Anacostia River watershed and has faced problems associated with urban runoff. Capturing some rainfall before it reaches the stream can reduce both the speed and pollution burden of that water.

The project was also tied to neighborhood participation. Residents on the block had taken part in Washington's RiverSmart Homes program. That participation helped make Hamlin Street a natural location for a larger neighborhood stormwater retrofit.

How do Hamlin Street bioretention systems work?

Bioretention systems are designed to make developed land behave more like natural ground. Stormwater enters a planted area instead of immediately disappearing through a conventional drain. Soil and other engineered layers then slow the water and help capture pollutants.

The Hamlin Street project combines those planted areas with underground stormwater chambers. That combination creates additional storage beneath the surface. It allows the relatively small street-side spaces to handle more water than landscaping alone could manage.

The basic idea is straightforward, but the engineering matters. Water needs to enter the system without overwhelming it during a storm. The system must also provide enough space for temporary storage before water moves onward or soaks into the ground.

Nearly 20,000 gallons is enough to show that this is more than decorative street landscaping. The systems were built to perform a specific stormwater management job within a developed neighborhood.

The project manages runoff from several acres while fitting into an existing street environment. That makes the approach interesting for cities dealing with limited space. Instead of relying only on large drainage projects, smaller sites can become pieces of a broader stormwater network.

That does not mean two systems can solve Hickey Run's water-quality problems alone. Their value comes from reducing runoff at one location before it travels farther downstream. Similar projects can then build on that effect across an urban watershed.

Why does the project matter beyond Hamlin Street?

Washington's experience reflects a broader challenge facing American cities. Older urban areas often have extensive paved surfaces and drainage networks built around moving water away quickly. Climate and development pressures can make managing that runoff increasingly important.

Green infrastructure offers another way to approach the problem. Vegetated systems can be placed where rainfall already collects, allowing cities to manage water closer to its source. Hamlin Street demonstrates how that strategy can work within a neighborhood rather than only on large open sites.

The project also received recognition from the Chesapeake Stormwater Network. In 2025, the network named the Hamlin Street retrofit a "Small But Mighty" award winner. That recognition reflects the project's practical use of limited urban space for stormwater management.

What can Washington learn from one neighborhood project

The most useful lesson may be how ordinary infrastructure can serve another purpose. A residential street does not need to become a massive construction site to help manage stormwater. Carefully designed spaces beside the road can capture water while remaining part of the neighborhood.

For people living nearby, the benefit is easy to overlook because much of the system operates quietly. There is no dramatic machinery or visible treatment plant. Rain simply enters a designed landscape, slows down and receives treatment before continuing through the watershed.

That is what makes Hamlin Street worth watching. The project does not promise to fix an entire watershed by itself. It shows something more practical: many modest interventions can change how a city handles rainfall, one neighborhood at a time.