Centre and Herron Green Stormwater project located in the Upper Hill District

We are building new stormwater solutions to reduce flooding, decrease water pollution, and change Pittsburgh's infrastructure for the better.



Pittsburgh’s first sewer lines were constructed in the 1840s in what is now present-day Shadyside and Oakland. These lines sent water directly to the Monongahela River. By 1908, nearly 400 miles of underground sewer lines were in place, establishing the start of our 1,200-mile combined sewer system.

Historic Photo, PGH2O

Today, Pittsburgh looks a lot different.

There are more buildings, more roads, less green space, and greater demand placed on our infrastructure. While many things have changed, the way we treat wastewater and stormwater largely remains the same.

What does all this mean?

Rendering of a completed stream restoration near Nobles Lane and Ansonia Place

Our combined sewer system sends wastewater and stormwater through one pipe to ALCOSAN, the regional wastewater treatment plant located along the Ohio River. Once water is treated, it is released into the river for downstream communities to use as drinking water.


Our sewer system is overwhelmed by the increasing intensity and frequency of rain. And with so much pavement and hard surfaces throughout the city, all this rain has nowhere to go.


Sewage frequently overflows into rivers, floods our streets, and overflows into basements throughout Pittsburgh. This method of sending wastewater and stormwater through one pipe is no longer acceptable.

How are we addressing this problem?

A bioretention area at the Hillcrest Stormwater Project in Pittsburgh's Garfield neighborhood.

We are building a new wave of stormwater infrastructure that captures the rain where it falls, soaks into the ground, and is slowly released back into the sewer system.


They use a combination of green and gray infrastructure that on the surface mimic nature using vegetation, engineered soils, and open channels that retain water. Underneath are storage systems that hold water back before slowly releasing it through our network of sewer pipes.


The new projects are cost-effective and help to reduce basement backups, sewer overflows, and improve water quality. As we build up our network of stormwater infrastructure throughout Pittsburgh, they will become more effective at addressing some of our most crucial stormwater challenges. For more information about our plans to manage stormwater, including the proposed stormwater fee, please visit

See green stormwater infrastructure in action.



Man riding bike during rainstorm in Pittsburgh

As heavier and more intense rains overwhelm our sewer system, stormwater management is a growing concern throughout Pittsburgh. Heavy rains cause sewage to overflow into rivers and streams, flood our streets, and backup into basements. To solve the problem of too much stormwater, we are managing it more deliberately across Pittsburgh.

Read more about the stormwater program and the plans we are implementing.



Rain garden at Wightman Park in Squirrel Hill

There is currently no comprehensive approach to managing stormwater in Pittsburgh. As PWSA transitions to the agency responsible for managing stormwater, we must think differently about how we fund stormwater projects and initiatives.


The stormwater projects, recently constructed by PWSA, are funded using revenue collected through the wastewater conveyance charge on your water and sewer bill. This is based on water usage, which has nothing to do with stormwater. 

Image of parcels on a city street showing hard surfaces

A more equitable approach is to charge a stormwater fee that is based on a property's impervious or hard surfaces such as roofs, driveways, patios, and sidewalks. This ensures that all property owners in Pittsburgh contribute a share that is proportional to the amount of runoff generated by their property. 

Proposed Stormwater Fee

Image of the sun setting over the Allegheny River

In April 2021, we submitted a request to the Pennsylvania Public Utility Commission (PUC) to change how we bill for stormwater services. The stormwater fee would provide a dedicated funding source to improve stormwater management, build innovative stormwater infrastructure, and reduce sewer overflows and pollution entering our rivers and streams. 


If approved, it will create a more equitable way to fund the stormwater projects and initiatives that are needed to better manage stormwater in Pittsburgh – ensuring everyone pays their fair share. Learn more about the proposed stormwater fee at



A rain barrel collecting water from a house gutter by a garden

Everyone in Pittsburgh needs to become part of the stormwater solution. You can make a difference by taking small actions every day to manage stormwater on your property, improve the quality of our rivers and streams, and protect those you care about during the large storms that frequently occur in Pittsburgh. Explore our stormwater pages for helpful resources and tips.


  • Help Manage Stormwater: Learn how you can become part of the stormwater solutions that are needed in Pittsburgh.
  • Find Your Sewershed: Use this searchable map to find which sewershed you live in and its contribution to combined sewer overflows (CSOs) to our rivers. 
  • Flood Preparedness: Learn how to protect your family, property, and belongings from flooding. 

Building Stormwater Solutions Together