Photo of the Herron Hill Reservoir and Tank

Our drinking water system contains approximately 965 miles of water lines, five reservoirs, and 11 tanks with a water storage capacity of 455 million gallons. 

In addition, we provide bulk water to Reserve Township, Fox Chapel, and Aspinwall, along with being interconnected to several other regional water systems for emergency purposes. 

Our water distribution system, built nearly a century ago, is a vast, complex network that was designed to take advantage of Pittsburgh’s unique geography. Gravity, along with the help of pump stations, reservoirs, and tanks, moves water throughout Pittsburgh’s hills and valleys. 

It has served us well for generations, and we are now making the necessary improvements to ensure the delivery of safe, reliable water for future generations. Our capital improvement program identifies the investments we will make in our drinking water over the next several years. 

Improving Our Infrastructure

Homewood water main replacement PWSA construction crew digging trench to replace a water main

Within the capital program, there are two categories of water projects. The first is the replacement of water mains and the ongoing replacement of lead service lines throughout the distribution system. These projects, happening in numerous Pittsburgh neighborhoods and Millvale, are a major investment to improve water quality and reliability for Pittsburgh residents. 

The 2020 Water Main Replacement Program, which will continue in 2021, will replace approximately 14 miles of water mains and any lead service lines found during the work. This will improve service reliability and water quality for thousands of residents throughout our distribution system.  

For more information on this project, visit the 2020 Water Main Replacement main page.


Historic photo of crews constructing original Clearwell circa 1906 Clearwell in construction - 1908

The second category is a series of once-in-a-generation projects to renew key components of our water production and distribution system, called the Water Reliability Plan. To prepare PWSA for the next 80-100 years, there must be resiliency and redundancy in every part of the system.

Resiliency means that all crucial portions of the system, like pump stations and large-diameter water mains will deliver reliable and safe water service to our customers for years to come. Redundancy means that if there is a failure, the system is designed in such a way that there is always another way to supply water and maintain service for our customers.  

Water Reliability Plan Projects

Lanpher Rising Main Project

This project will build a five-mile-long, 48-inch pipe to carry water from the Water Treatment Plant to the Lanpher Reservoir, located in Hampton Township. 

Water Treatment Plant Electrical Power and Backup Projects

These efforts will ensure that our pump stations never lose power. When our pumps are in good working order, we maintain consistent water pressure throughout the water service area.  

Water Treatment Plant Pump Station Upgrades

Ensuring our pump stations are in good condition will help to maintain good water pressure throughout our water service area. 

Highland 2 Reservoir Improvements

The Highland 2 Reservoir is one of the largest water storage facilities in our service area, providing water to most of the East End of Pittsburgh as well as some of the South Side and West End. We will replace the reservoir cover, pump station rehab, and rehab work on the rising main coming from the reservoir will ensure reliable service for years to come. 

Rising Mains 3 & 4 Upgrades

These large-diameter pipes carry water from the Water Treatment Plant to the Highland Reservoirs. Making any repairs to these pipes will ensure there is reliable water service for many of our customers.  


These Water Reliability Plan projects will work together to fortify the system so it is ready to supply continuous water service during the final, and biggest project, the complete restoration of the Clearwell. The Clearwell is a large, century old water storage facility that is used to dose water with chlorine to kill any harmful bacteria or pathogens in the water. It is a unique component in our system and provides a crucial treatment step for the health and safety of our water. Since there is only one Clearwell, PWSA engineers must phase their work so they can prepare to chlorinate water elsewhere while the Clearwell is under construction. As the last of these Water Reliability projects, this project will be a $67 million investment in PWSA’s water future.  

Over the next five years, PWSA will invest nearly $300 million in large-scale water improvement projects. This comprehensive series of projects will provide a resilient and redundant water system that the people of Pittsburgh can rely on for many years to come.  

Water Quality & Treatment

Our dedicated staff at the water treatment plant and in our lab are constantly monitoring and measuring the quality of our drinking water to ensure that it meets all state and federal drinking water requirements. Learn more on our Water Quality & Treatment page.