Philadelphia Faces a Rising Tide of Water Challenges

Philadelphia has a long history of water leadership and innovation. But the growing number of water challenges Philadelphia faces from the maintenance and cost of aging infrastructure to the impacts of climate change remain a looming concern for the city.   


Philadelphia Regional Summary

Philadelphia is one of the earliest developed cities in the United States, and one of the first cities in the country to supply fresh water to its citizens through a public water system. However, multiple and cumulative impacts throughout Philadelphia’s regional and local watersheds, are posing critical water related challenges for Philadelphia, similar to what many cities are facing nationally.

Philadelphia’s water source is surface water from the Delaware and Schuylkill Rivers. Its location at the bottom of the 12,800 square mile Delaware watershed, means that all upstream impacts affect Philadelphia’s sourcewater. These impacts include development pressures, resulting in an increase in impervious surfaces and forest clearing, and a decrease in riparian buffer zones, stormwater runoff, agricultural runoff, combined sewer overflows, spills and accidents, treated wastewater effluent, improper disposal of trash/waste, legacy pollutants and emerging contaminants. Comprehensively addressing these issues at a watershed scale is difficult considering the fragmented governance and variable finances of upstream municipalities. Although Philadelphia has more capacity, justifying the spending of ratepayer funding on upstream municipality issues is not easy.

The Clean Water Act of 1972 and The Safe Drinking Water Act of 1974 have set the standard for surface water quality and ensuring drinking water safety. To better integrate approaches to meet these mandates, and organize activities at a watershed scale, The Philadelphia Water Department (PWD) established the Office of Watersheds in 1999. PWD also established the Source Water Protection Program focused on achieving source water goals through regional partnerships, outreach and education, advanced technologies, research projects and on-the-ground implementation and monitoring. PWD, in collaboration with its regional partners, conducted a watershed-scale assessment and identified sources of contamination. PWD developed the Source Water Assessment into a Source Water Protection Plan to prioritize and guide efforts within the watersheds.

On a national and local scale, aging infrastructure is a significant challenge. PWD manages more than 3,000 miles of water infrastructure, 3 water treatment plants and over 25 water pumping stations. Philadelphia’s underground sewer network is approximately, 3,000 miles and includes both combined sewers and separate sewers requiring continuous inspection and maintenance, due to age and demand. The need for ongoing assessment of water infrastructure in Philadelphia is both expensive and difficult to manage and plan for. Emergency repairs and maintenance add additional pressure and costs on PWD’s operations with impacts to private property, business, traffic delays and service losses. Massive investments are needed for water, wastewater and stormwater infrastructure, while commensurate funding continues to be challenging due to affordability considerations, undervaluation of services and infrastructure by the public, including drinking water, and potential new bond rating considerations, including climate risks.

Furthermore, with aging infrastructure comes the compounding challenge of water affordability.
As a response, in 2017 PWD created the groundbreaking income-based water tariff system known as the Tiered Assistance Program (TAP). Through TAP, households are charged a percentage of total monthly income (between 2 and 4%) based on the household’s percentage of the Federal Poverty Level (FPL), with the lowest percentages of FPL being charged the lowest percentage of income. TAP is seeing initial success with over 5,000 households currently participating in the program but ensuring equitable access of this service remains a challenge.

Stormwater runoff and combined sewer overflows are a significant concern for Philadelphia. Once a city of streams, Philadelphia’s hydrology and topography was drastically changed by the conversion of these streams and smaller creeks to sewers in the mid-19th century, creating the combined sewer system which still serves a majority of Philadelphia. Today, only 118 miles of streams remain out of 283 linear miles of streams that once existed in Philadelphia. To reduce combined sewer overflows, the Philadelphia Water Department put forth a 25- year plan, Green City, Clean Waters, which proposed a triple bottom benefit approach to managing combined sewer overflows and its impacts on Philadelphia’s streams and rivers. In 2011, the plan was formally adopted by the City of Philadelphia and PWD through a signed Consent Order and Agreement with the Commonwealth Department of Environmental Protection (DEP) detailing Philadelphia’s $2.1 billion plan. In contrast, many cities are spending tens of billions of dollars to build tanks and tunnels to come into compliance. Successful implementation of the Green City, Clean Waters plan is dependent on partnerships and aligned investments with City agencies, allowing PWD to access public land for stormwater management, with private sector entities that develop or retrofit properties, and with outside organizations that leverage additional resources.

Philadelphia is confronted with an increase in flood risk to both properties and natural areas, resulting in dangerous and costly localized flooding due to steep slopes, a high water table, or sewer system capacity issues. PWD has dedicated funding to reduce and mitigate flood risk throughout Philadelphia. PWD also participates in Philadelphia’s Citywide Flood Risk Management Task Force to coordinate City agencies in addressing flood issues and attract Federal and State support.

Philadelphia is also preparing to face imminent challenges, including changes to current and future regulatory requirements regarding stormwater management for both the combined sewer area and the separate sewer area, and most importantly climate change impacts. Temperature increases can degrade source water quality making treatment more difficult, while an increase in precipitation will increase stormwater runoff, and combined sewer overflows, localized flooding and erosion. An increase in sea level rise can flood PWD’s critical assets, result in more infrastructure damage from extreme events, impact Philadelphia’s pipe infrastructure, and shift the salt line, affecting the Delaware River source water intake. To fully understand and develop adaptation strategies to minimize climate change impacts, PWD established the Climate Change Adaptation Program (CCAP).

Philadelphia’s long history of water leadership will be put to the test in the coming decades. Like other cities throughout the US, PWD needs to transform its aging infrastructure and address watershed and local impacts with a resiliency focus, ensuring adequate, high quality drinking water, and system services for Philadelphia residents at an affordable cost. If PWD can meet this challenge, it may just be Philadelphia’s greatest feat yet.