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Chester, Pennsylvania, located in Delaware County just southwest of Philadelphia, was founded in 1681, making it the oldest city in the state. Situated directly on the Delaware River, Chester was a manufacturing and industrial community for much of its history, though that activity began to decline starting in the 1950s. That legacy and other factors make the city of 32,000 potentially prone to a catastrophic toxic flooding event, now and in the future as the effects of climate change continue to intensify.

Despite the decline in development and population growth (the city lost more than half its population between 1950 and today), remnants of Chester’s industrial history remain. The most well-known — and most controversial — facility is the Covanta incinerator known as the Delaware Valley Resource Recovery Facility. This waste-to-energy incinerator takes solid waste from Delaware County and other parts of Pennsylvania, New York, New Jersey, and Maryland and burns it to generate electricity.

Just down the road, Monroe Energy’s Trainer Refinery produces jet fuel, gasoline, diesel, and home heating oil. The DELCORA wastewater treatment plant accepts industrial and municipal wastewater, sludge, and grease, which it then treats and returns to the Delaware River. A PQ Corporation chemical manufacturing facility is also located in Chester, along with a Kimberly-Clark paper mill.

This concentration of polluting facilities is especially concerning when one looks at the demographics of the community bearing the burden of associated health and environmental risks.

Toxic floodwater risks and environmental justice

Chester is what is known as an “environmental justice area,” defined by the Pennsylvania Department of Environmental Protection (PADEP) as any census tract where more than 20 percent of the population lives at or below the federal poverty line or more than 30 percent of the population are people of color. More than 70 percent of Chester residents are people of color, and the median household income is $35,751 (in 2021 dollars). Compare this to Delaware County as a whole, where 33 percent of county residents are people of color, and the median household income is $80,398.

The health and environmental hazards associated with living in close proximity to facilities such as waste incinerators, oil and gas refineries, wastewater treatment plants, chemical manufacturers, and paper mills are numerous and well-documented. In Chester and similar communities across the country, exposure to air pollutants like noxious gases (NOx) and particulate matter (PM) can cause an increased risk of asthma, respiratory diseases, and cancer. Facilities located near lakes and rivers may also discharge pollutants directly into the water, leading to increased risk of drinking water contamination or other chemical exposures.

There is an additional environmental risk that is exacerbated by climate change. Toxic flooding occurs when floodwaters become contaminated with chemicals and hazardous materials, spreading these pollutants to the surrounding community and environment. Toxic floodwaters can contaminate drinking water, and exposure can lead to intestinal problems, headaches, and other illnesses. Additionally, floodwaters can wash pollutants into rivers and lakes, harming wildlife.

Climate change presents a worsening risk of flooding events due to sea level rise and the increasing severity and frequency of hurricanes and other extreme storms. The greater the number of polluting facilities in flood-prone areas, the greater the risk of toxic flooding.

Toxic floodwater risks in Chester

Chester provides an illustrative example of this risk. Located on the tidal portion of the Delaware River (the part of the river affected by ocean tides), the city’s riverfront is vulnerable to both sea level rise and severe weather events. Most of the active and shuttered industrial facilities are located in this area.

In 2016, as part of the process to improve Chester’s stormwater infrastructure, professors at Widener University submitted a preliminary report to the Pennsylvania Sea Grant, assessing the number of brownfields in the city at risk of flooding. The report found 31 potential brownfield sites, which are defined by the U.S. Environmental Protection Agency (EPA) as “real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.” Of those 31 sites, the report found that 19 of them were at risk of flooding.

Brownfield properties are often empty, abandoned, or unmaintained. Hazardous pollutants frequently remain on the properties, left over from their industrial uses, and unscrupulous entities may illegally dump additional trash and hazardous waste in these areas. Left unmonitored, these properties pose an often unknown but very real threat of toxic flooding in Chester.

Brownfield properties are not the only source of possible toxic floods in the city. Many of the active industries in the city are located along the riverfront. A brief analysis using the FEMA Flood Map Service Center shows that all or part of several of these facilities, including the Covanta incinerator, Monroe Energy refinery, PQ Corp chemical manufacturer, and Kimberly-Clark paper mill, are located in flood hazard areas.

Possible policy solutions

Laws such as the Clean Water Act require such facilities to develop stormwater pollution prevention plans and spill prevention, control, and countermeasure plans, which help address the risk of onsite pollutants entering the water as a result of flooding and severe storms. However, facilities that are out of compliance with these requirements increase the possibility of toxic flood events.

The risk posed by toxic flooding can be addressed in a variety of ways:

Stay tuned to this space for more on toxic flooding and other hazards in the Delaware River basin in the weeks and months ahead, and be sure to follow us on social media and subscribe to our email list.