Updated July 24

Penn Environment is a valued partner to PWD and was instrumental in the establishment and adoption of the Green City, Clean Waters (GCCW) program. We appreciate their continued passion for our mission to achieve clean and healthy rivers and streams. 

As Penn Environment noted in their July 20 “Sewage Pollution in Philadelphia” post, the combined sewer overflow (CSO) charts in their report were obtained from our own annual reporting. We live and breathe these numbers every day. As our spokesperson stated in our initial July 20 response, we have multiple projects under construction designed to further reduce CSOs by an additional 600 million gallons annually in the next three years. We are striving to do more, but we must balance the cost of these massive infrastructure improvements with what our ratepayers can afford.  

The Penn Environment report’s assertions do not consider the complexity of implementing the current Green City, Clean Waters initiative in addition to the challenges associated with adding more infrastructure projects at a greatly accelerated rate.  PWD is already committed to over $4.5 billion in capital program infrastructure investments through fiscal year 2029, with nearly $1 billion of that dedicated to CSO mitigation. Even if we were to receive the entire state-wide allocation Pennsylvania is expecting for sewer investments from the Bipartisan Infrastructure Law over the next four years, it would still only be a fraction of the funding needed for the magnitude of improvements required to mitigate all combined sewer overflows stemming from our aging sewer system.  

By working with our regulatory partners at the Pennsylvania Department of Environmental Protection (PA DEP) and the Environmental Protection Agency (EPA) we have committed to a progressive stormwater management program that consists of incremental improvements over a 25-year period and keeps the impacts on our ratepayers at the forefront.   

When evaluating the city’s rivers and streams and water quality impacts, it is important to remember that we are downstream of approximately 10,000 square miles of vast watershed areas that flow through hundreds of communities, multiple states, thousands of non-point pollution sources—such as farms and parking lots—and hundreds of point sources, such as wastewater treatment plants and stormwater outfalls conveying stormwater and treated wastewater to local waterways. These potential pollution sources are all upstream of Philadelphia. Numerous City of Philadelphia departments are collectively responsible for the environmental welfare of our citizens, for example. Philadelphia Parks and Recreation manages the trails and waterfront access and PWD and other dischargers work to improve water quality, while the Philadelphia Department of Public Health and Police Marine Units do their part improving health and safety associated with near-shore and in-stream activities.  

The suggestion in the report that, were it not for potential bacteria associated with combined sewer overflows, Philadelphia’s rivers and streams would be safe for recreation following storms fails to acknowledge the extremely dangerous conditions in these waterways following precipitation events. On normal and low-flow days, there are far more barriers to swimming in urban rivers and streams than those posed by sewer overflows, including strong currents, dangerous submerged objects, and forceful tides. Even in a dry start to the summer of 2023, there have been two tragic drowning deaths in Philadelphia streams this year.   

What we have done

As noted in articles covering the Penn Environment post, PWD has made significant progress in reducing CSOs in the first 12 years of the Green City, Clean Waters program. As of the last required regulatory reporting period in 2021, PWD reduced the annual average CSO volume by 3.08 billion gallons, exceeding the required CSO volume reduction target of 2.044 billion gallons by more than 1 billion gallons. This includes nearly eliminating all overflows from one of the largest outfalls in Tacony Creek. This three-billion-gallon annual CSO volume reduction is close to about 40 percent of the total CSO volume reduction goal that we have set for ourselves.  

PWD is committed to implementing a multitude of stormwater projects, leading to incremental volume reductions for years to come. PWD has projects under construction that will reduce CSOs by another 600 million gallons annually in the next three years. In addition to the green stormwater infrastructure projects that are being implemented throughout the city, there are several larger projects that are anticipated to be completed that will have significant impacts on reducing CSOs, including modification to regulator chambers, interceptor expansion, and construction of a pretreatment building at the Northeast Water Pollution Control Plant that will allow more flows to be treated at that plant.  We received a $100 million, low-interest, federally backed PENNVEST loan to help finance this project and reduce impacts on our ratepayers over time.   

What we still need to do

PWD has 13 years remaining in the approved Consent Order Agreement (COA) and Administrative Order for Compliance on Consent that formalized the Green City, Clean Waters program, with nearly five billion gallons of additional CSO volume left to eliminate annually. At the completion of Green City, Clean Waters, we are targeting to reduce CSOs by approximately eight billion gallons in the typical year from the original 13 billion gallons. There are benchmark performance standards outlined in five-year intervals, with the next at Year 15 of the program in 2026. Throughout the implementation process, we will continue to develop and refine approaches to meet each COA Performance Standard while balancing PWD’s other significant water resource priorities at our drinking water treatment plants and throughout our water, stormwater, and wastewater conveyance systems. 

Background on Combined Sewers

Overflows that impact our waterways occur because we are preventing overflows on our neighborhood streets and at treatment facilities providing critical services.  

During dry weather, the combined sewer system and wastewater treatment plants have the capacity to transport and treat all the sanitary sewage entering the system (including flow from PWD’s wholesale customer communities). However, when flow in the combined sewers increases as a result of rainfall or snowmelt, the sewer pipes and treatment plants may reach their capacity. When this happens, the US Environmental Protection Agency (US EPA) permits Philadelphia, as it does with approximately 800 cities across the country with combined sewer systems, to discharge excess combined sewage (mixed wastewater and stormwater) into nearby waterbodies to prevent health and human safety issues that may result from localized flooding in neighborhoods and in treatment plants. We would like to reiterate that the average annual content of sewage in the combined sewer overflow is approximately 10 percent, with the remaining 90 percent consisting of rainwater from storms. 

Replacing the entire combined sewer system in Philadelphia would be prohibitively expensive and infeasible, for many reasons. As a utility, PWD must make difficult decisions about our drinking water, wastewater, and stormwater systems in order to balance priorities, like reliable access to clean drinking water, and the costs, which are passed on to our customers through water bills. PWD’s 25-year plan to reduce CSOs is a work in progress—Green City, Clean Waters is a multi-billion-dollar investment in traditional and green infrastructure. We are investing the time and money needed to address the problem of CSOs. This plan represents a robust and ambitious program that balances regulatory priorities with the pace of implementation along with maximizing benefits to our ratepayers.   

The plan and its timeline are not arbitrary – it took many years of collaboration with state and federal regulators and key stakeholders and environmental advocates like Penn Environment to design a solution that is feasible and that can be implemented at a pace that our customers can afford.  

Regulatory context

PWD is a regional drinking water, wastewater, and stormwater management entity with wholesale customer contracts with several neighboring municipalities. As the utility managing water quality in receiving waters downstream from hundreds of miles of urban and suburban development, we are mindful of water supply protection as well as receiving water quality and the implications of lack of proper management during large-scale events.   

PWD produced a CSO Long-term Control Plan Update in 2009, updated through negotiations and formalized through a Consent Order & Agreement (COA) with the Pennsylvania Department of Environmental Protection in 2011 and an Administrative Order for Compliance on Consent (AOCC) with the United States Environmental Protection Agency 2012. The Green City, Clean Waters program was met with overwhelming endorsement and support from the environmental NGO stakeholder community, including Penn Environment. PWD’s agreements require the reduction of CSOs through the implementation of green stormwater infrastructure, treatment plant improvements, and sewer system projects. The COA outlines a 25-year implementation duration with the inclusion of a Water Quality Based Effluent Limit (WQBEL) table listing benchmarks for progress PWD must achieve by dates throughout the 25-year implementation horizon.  At the beginning of the program in 2011, Philadelphia experienced 13 billion gallons per year of CSO in a typical year.    

Dry weather water quality has been a priority of PWD for decades. PWD is committed to reducing dry weather flows in the City’s municipally separate sewer system (MS4) through our Defective Lateral Abatement Program. It is worth noting that when comparing the scale of water quality impairments, dry weather discharges in the MS4 portions of the city are on a far smaller scale than CSO discharges during wet weather.   

CSO outfalls do not discharge during dry weather conditions and PWD maintains a vast network of monitors in the combined sewer system that we use for operating purposes to make sure that there are no dry weather overflows from the CSO outfalls.   

When sanitary capacity issues in the form of Sanitary Sewer Overflows (SSOs) were identified they were addressed by adding new infrastructure. PWD is committed to ensuring these discharges are remediated and continues to closely monitor locations with known capacity challenges.  

Balancing regulatory priorities

PWD has resources dedicated to the management of aging assets, compliance with multiple types of regulatory obligations, and a series of emerging issues and public health interests, as well as the occasional unpredictable and sometimes unavoidable emergency. Each of these focus areas necessitates dedicated staff resources and funding to establish scopes, schedules, and measurable benefits. PWD remains committed to reducing CSOs through a multitude of asset enhancements and project implementation.  

However, an initiative of this scale requires sufficient time to implement. PWD is heavily investing funding and resources in many other programs, including our Drinking Water Revitalization Plan, Wastewater Revitalization Plan, Climate Change Adaptation Program, and asset management, among others, to address other regulatory requirements. We are simultaneously investing in protecting and replacing drinking water and wastewater infrastructure. We are spending a tremendous amount of money to make substantial progress in those areas as well, while also making progress in reducing CSOs.    

It takes a great deal of time to plan for infrastructure investments as we must investigate to understand the source or cause of an issue, evaluate ways of addressing it, and consider how projects to address one issue may fit in with future needs or obligations. We must work closely with our regulatory agencies to determine approval for projects as they fit within compliance approaches. We must also engage the on-the-ground local stakeholder community impacted by the siting, construction, and long-term neighborhood impact of a given project. Needless to say, this scale of planning takes years. It is then often complicated by a dynamic environment whereby the regulatory priorities, economic climate, or on-the-ground conditions can change. These added complications help to focus PWD’s attention on defined obligations when planning projects.  

Why acceleration is challenging  

 The water resources programs that PWD is leading are complex, costly, and resource intensive.    

Additional funding, especially in the form of grant funding that could potentially reduce burdens on water bills, would certainly be valuable and PWD is advocating for this. Our ratepayers are paying for these increasing regulatory obligations. However, there seems to be a misconception that additional funding alone might lend itself to either project acceleration or additional project implementation. While this may be possible in some instances, the challenges with acceleration are both time-based and financial.  

PWD must remain focused on planning for known regulatory obligations while being mindful of potential changes to ensure that projects planned for today are not incompatible with future needs, while remaining agile to address emergencies and other pressing priorities as they emerge. With this balancing of priorities, it is not often prudent to have massive, resource-intensive extra projects that would cost hundreds of millions of dollars identified, planned, designed, and ready for construction prior to the planned implementation. Projects are planned based on program priorities, regulatory obligations, and their relationship to future projects, as many are interrelated in their function and benefit.  

It is simply not realistic to move the goalposts on a massive, 25-year initiative at the halfway point to dramatically increase the implementation pace or add new projects. Even if funds were unlimited, the resources to support acceleration are not. It would likely take more than a decade to plan, design, and implement the drastic changes to Green City, Clean Waters that are being alluded to.  

The entire $70.5 million that Penn Environment cites in Pennsylvania’s allocation for Clean Water State Revolving Funds could be used for a single large project in Philadelphia, leaving no funds for any other part of the Commonwealth. Additionally, these funds are overwhelmingly available as loans that must be repaid.  It’s imperative the public and stakeholders understand the limits of existing state and federal funding for CSO mitigation projects.

Philadelphia continues its decades-long investment in improving the health of local waterways and is making tremendous strides in meeting the vision of the Clean Water Act. In order to continue that progress and meet the needs of the customer base that funds our work and depends on our infrastructure for access to affordable, clean water, we must balance our priorities and make investments that protect public health while continuing to improve the health of our rivers and streams.  

Investments that balance the needs of our neighborhoods with the continued improvement of our waterways is the at the heart of the Green City, Clean Waters approach to addressing combined sewer overflows.