Trends in surface-water quality during implementation of best-management practices in Mill Creek and Muddy Run Basins, Lancaster County, Pennsylvania

Abstract

Status yields and trends of nutrients and sediment and methods of analysis for the nontidal data-collection programs, Chesapeake Bay Basin, 1985-96: U.S. Geological Survey Open-File Report 98-17, 60 p.

Concentrations and Loads of Nutrients and Suspended Sediments in Englesby Brook and Little Otter Creek, Lake Champlain Basin, Vermont, 2000-2005

“…19). This pattern is consistent with concentrations of phosphorus during base flow found in an agricultural stream in Pennsylvania (Koerkle, 2000).…”

“…Also, streambank fencing improved sediment concentrations and some sediment yields but not nitrogen or phosphorus yields for storm samples. Another Pennsylvania study concluded that streambank fencing, in conjunction with other BMPs, resulted in reductions of flow-adjusted concentrations of phosphorus and suspended solids in base flows, and a reduction in suspended solids in storm samples (Koerkle, 2000). A third Pennsylvania study showed that pipe-outlet terracing reduced sediment loads but not nitrogen or phosphorus loads and that nutrient management reduced dissolved nitrate in ground water (Lietman, 1997).…”

Nitrate Removal in a Restored Spring‐Fed Wetland, Pennsylvania, USA1

“…Because nitrate dominates the total nitrogen load in many agricultural landscapes (Koerkle et al. , 1996; Koerkle, 2000), denitrification in wetlands can have a substantial impact on total nitrogen loads.…”

“…Denitrification is quantitatively the most significant water quality improvement process in surface flow wetlands (Watson et al, 1989;Reddy and D'Angelo, 1994;Bavor et al, 1995;Bachand and Horne, 2000) and occurs as anaerobic heterotrophic bacteria typically found below the soil surface use inorganic oxides of nitrogen (NO 3 ) and NO 2 ) ) as their energy source, releasing gaseous end products (N 2 O and N 2 ) (Knowles, 1990). Because nitrate dominates the total nitrogen load in many agricultural landscapes (Koerkle et al, 1996;Koerkle, 2000), denitrification in wetlands can have a substantial impact on total nitrogen loads.…”

Effects of legacy sediment removal and effects on nutrients and sediment in Big Spring Run, Lancaster County, Pennsylvania, 2009–15

“…Big Spring Run flows north and joins Mill Creek, which is a tributary to the Conestoga River. The Conestoga River and Mill Creek watersheds have been identified as important contributors of nutrient and sediment loads to Chesapeake Bay (Koerkle, 2000;Gellis and others, 2004). Many stream reaches in the Conestoga River and Mill Creek watersheds are impaired, including Big Spring Run, which is listed for aquatic life, construction, siltation, habitat modification, and unknown toxicity (Pennsylvania Department of Environmental Protection, 2014).…”