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Research and Planning

The programs we implement to improve the health of Philadelphia's waterways are directly informed by our extensive research and planning efforts.

Studying land cover trends of the Delaware Watershed informs strategies to protect source water in the future.


River Trends

Studying the trends of a river’s flow, quantity and origin over time can be a powerful tool to help us project what future changes to expect. Extracting hints from recorded historical data allows us to anticipate what the future conditions of a river may be.

Modeling Software

We rely on modeling software to provide supporting scientific data. The modeling results can tell us how well our infrastructure is working, which in turn can inform the actions we take to make our flow storage, conveyance, and treatment more efficient.

Future Influences

Researching potential future influences helps us accurately gauge possible impacts on our drinking water supplies, the Delaware and Schuylkill rivers. Our objective is to predict and prevent potential threats to the source water intakes located along these rivers as well as throughout Philadelphia's watersheds.

One major environmental influence is climate change and the various associated components. One example is sea level; as sea levels rise, the encroaching salt line becomes a threat to the drinking water treatment process. Monitoring sea levels allows us to know if and when reexamining our treatment process is a priority, as it currently is not designed to remove salt. Another component of climate change is surface temperature; we monitor temperature trends to predict the influx of bacteria growth as well as the frequency of severe storms and short-term droughts. Vegetation is yet another aspect affected by climate change, as the type, distribution and coverage of vegetation corresponds to precipitation and surface temperature. Researching these trends helps us anticipate potential plant loss, which can be mitigated through various green infrastructure initiatives.

In addition to researching climate change, source water health can also be detected through studying changes in population. The environment can only sustain the necessities for survival – food, water, living spaces, etc. – until it reaches its full capacity. Through the study of population changes, we can predict when an area’s capacity will be reached, and consequently, when the water supply may expire. Furthermore, the anticipated stress on our conveyance and treatment infrastructure helps us gauge how and when mitigation will be reactive rather than proactive.

Source Water Assessments

In order to identify watershed-wide priorities for improving source water, we conduct source water assessments with other stakeholders in each watershed. These assessments are intended to be a collaborative effort among all parties with the common interest of improving the quality of our drinking water sources. Coalitions are formed to provide data and resources so stakeholders have them available. These assessments are living documents and are constantly being updated. This year’s research focus has been to examine water quantity in the Schuylkill River and the sustainability of the supply now and in the future.

Comprehensive Characterization Reports

In order to form the scientific basis for Integrated Watershed Management Plans, technical data is presented and discussed in Comprehensive Characterization Reports (CCR). These documents contain detailed technical information about land use, geology, soils, topography, demographics, meteorology, hydrology, water quality, ecology, fluvial geomorphology, and pollutant loads in a watershed. One CCR is prepared for each watershed, intended to be a single compilation of background and technical documents that can be periodically updated as additional field work or data analyses are completed.


River Conservation Plans

The Philadelphia Water Department views the River Conservation Planning process as a holistic approach to improving watershed health as well as a complementary initiative to the Integrated Watershed Management Planning Program. River Conservation Plans are developed through a collaborative process involving local organizations and residents and address various types of projects that will help make the watershed a more desirable place to live. They address broader concepts of how a combination of restoration, maintenance, and/or enhancement initiatives can preserve or improve history, water quality, culture, ecology, parks, art, trails, crime prevention, youth education, municipal education, and much more.

Integrated Watershed Management Plans

These plans present a logical and affordable pathway to restore and protect the beneficial and designated uses of the waters of a basin. Based on extensive physical, chemical and biological assessments, the plan explores the nature, causes, severity and opportunities for control of water quality impairments in the watershed. The primary intent of the planning process, as articulated by the stakeholders, is to improve the environmental health and safe enjoyment of the watershed by sharing resources and through cooperation among residents and other stakeholders in the watershed. The goals of the initiative are to protect, enhance, and restore the beneficial uses of the waterway and its riparian areas.

CSO Long Term Control Plan

We are always working to protect and preserve our water resources. This includes working on ways to control stormwater that also helps our waterways. Our plan to do this is called a Long Term Control Plan. Part of our plan includes studying our combined sewer systems, rivers and streams. This means we now know how our system is working, and where we can make changes to help it work better.

Philadelphia's original CSO Long Term Control Plan was submitted in January 1997 and contained three major elements: technology-based capital improvements, comprehensive watershed planning, and ongoing implementation of the Nine Minimum Controls. These controls are low-cost actions that can reduce CSO discharges and their effect on receiving waters, and they do not require significant engineering studies or lengthy implementation.

Our original Long Term Control Plan and capital improvements program were reevaluated in 2007 in an effort to integrate additional projects that would reduce CSO frequency and volume. Building on the experience and progress gained from the original plan, this process produced an update to the plan that involved newly-developed management alternatives to ensure capture and treatment of sanitary sewer system flows. Discharges from CSOs are also further reduced through the CSO Long Term Control Plan Update.

Source Water Protection Plans for the Schuylkill and Delaware River Watersheds

The Schuylkill and Delaware River Source Water Protection Plans make recommendations for action based on the source water assessments. Both plans focus on preventing spills in accidents, improving communication among water suppliers during emergencies, and maintaining forest cover critical to drinking water protection.