Transforming the impact and effectiveness of responses to “hot spots” and “hot moments” of water contamination.


All major Pennsylvania river basins have considerable nonpoint source nutrient and sediment pollution. In 2020, nearly one-third of Pennsylvania's streams were impaired, largely from agricultural runoff, abandoned mine runoff, and stormwater. Across the Chesapeake Bay, the Delaware Bay, and the Lake Erie and Ohio River watersheds, the impairment of streams is increasing despite millions of dollars spent to improve water quality. Most nutrients reaching these waterways are transported and transformed during brief periods of time (hot moments) in discrete elements of the landscape (hot spots).

Overcoming complex barriers to the success of water quality investments

Current management solutions largely ignore biophysical hotspots, giving equal credit, irrespective of where on the landscape best management practices (BMPs) are placed. For many BMPs, pollutant removal efficiency is variable through time – successful removal dramatically decreases during large pollution events, or requires multi-year solutions, as is the case with the development of riparian buffers. Typically, these temporal dynamics are not considered when implementing management solutions; and despite overwhelming documentation that maintenance and upkeep is required to maintain pollutant removal efficiency, credit isn't always given for maintenance. Close attention to the temporal variability of BMPs is required to effectively mitigate nonpoint source pollution.

In addition to the biophysical template, complex social, cultural, policy, and economic factors impact the cost effectiveness and willingness to pay for some BMPs over others. Emerging evidence suggests that many management dollars in the U.S. are funneled to a small number of municipalities, especially those in affluent neighborhoods. This initiative aims combine biophysical hotspots and socioeconomic hotspots to create a more realistic and nuanced understanding of sweet spots in the landscape that can produce more effective, cost efficient, and equitable nutrient reductions across the Commonwealth.


Jonathan Duncan, Ph.D.
Associate Professor of Hydrology
Department of Ecosystem Science and Management

Associated Members



Related College of Agricultural Sciences Research Impact Areas