Pittsburgh turns to trees and rain gardens to ease sewer overflows
Pittsburgh's combined sewer system carries both sewage and stormwater, and intense rain can cause overflows into rivers and creeks. Upstream Pittsburgh encourages rain barrels, street trees, and rain gardens with underground storage to capture water before it reaches the sewers. These measures aim to reduce local flooding and keep polluted runoff out of waterways.
Pittsburgh’s sewers mix household sewage with runoff, so when storms send more water than the system can handle, untreated wastewater can reach local waterways. Climate change is linked in the story to more intense rainfall, which makes these overflow events harder to manage.
Upstream Pittsburgh, a nonprofit, works with residents and communities on solutions that capture rain before it enters sewers. Examples include barrels attached to downspouts, street trees that absorb water, and rain gardens built on vacant lots with underground tanks that store stormwater until the sewer system can manage it.
Residents and communities in Pittsburgh could be affected if these approaches are adopted widely. Homeowners may reduce stormwater leaving their properties, while neighborhoods near creeks and rivers could see less local flooding and fewer polluted overflows. The benefits may depend on participation, maintenance, and how well the measures handle intense storms. City agencies and ratepayers might also face different infrastructure and cost pressures over time, though the story does not quantify those effects.