Philadelphia is situated in the southeastern portion of the Delaware Basin, and the city is supplied water from two rivers – the Delaware River and the Schuylkill River. The surrounding suburbs have a big impact on the quality of water that comes into our treatment facilities, and these suburbs are quickly-expanding. While the population of Philadelphia county has recently dropped about 22%, the subsequent populations of Montgomery and Bucks counties grew by 20% and 44% respectively. Both of these suburban counties are largely part of both the Delaware and Schuylkill watersheds.
The Delaware watershed is 330 miles long and runs from New York through Pennsylvania and New Jersey, all the way down into Delaware. It also provides water to a whopping 10% of all Americans. As with most watersheds across America, threats to the Delaware include waste dumping, bad agricultural practices, erosion/runoff problems, industrialization, transportation, and coal mining. Another common problem with pollution in the water supply that affects the Delaware is overflowing sewer systems from prolonged periods of rainfall. This problem has occured in many parts of the United States, and a good solution is to collect and store rainwater on a residential level, thus keeping a lot of runoff from flooding the overburdened sewer systems.
The Schuylkill watershed is 130 miles long and runs across 11 counties until it eventually merges with the Delaware in South Philadelphia. A lot of repeat problems plague this watershed, such as overflowing sewers, stormwater runoff, agricultural runoff, and abandoned mine drainage (Schuylkill county).
The Philadelphia Water Department (PWD) operates three plants in the area and does a good job of treating our water supply. Chlorine-resistant microorganisms, such as Cryptosporidium and Giardia, were detected in untreated water flowing into the facilities. After treatment, PWD tested the water quality for these microorganisms, and they managed to rid the water of all detectable amounts of both disease-causing organisms. Turbidity of water was significantly lower than required by state and federal law (80%).
