MD-DE-DC Water Science Center
Publications
Estimation of base flow by optimal hydrograph separation for the conterminous United States and implications for national-extent hydrologic models
Optimal hydrograph separation (OHS) uses a two-parameter recursive digital filter that applies specific conductance mass-balance constraints to estimate the base flow contribution to total streamflow at stream gages where discharge and specific conductance are measured. OHS was applied to U.S. Geological Survey (USGS) stream gages across the...
Foks, Sydney; Raffensperger, Jeff P.; Penn, Colin A.; Driscoll, Jessica M.
Effective solubility assessment for organic analytes in liquid samples, BKK class I landfill, West Covina, California, 2014–16
Executive SummaryThe U.S. Geological Survey assessed the effective solubilities of organic analytes at the BKK Class Ⅰ Landfill site, West Covina, California, in cooperation with the California Department of Toxic Substances Control, using available data for liquid samples collected within (in-waste) and below (sub-waste) the landfill in 2014–16....
Lorah, Michelle M.; Majcher, Emily H.; Morel, Carol J.
Hydrologic study at Farm Creek Marsh, Dorchester County, Maryland, from April 2015 to April 2016
In 2015, the U.S. Geological Survey began a 1-year hydrologic study to investigate the extent and cause of inundation at Farm Creek Marsh, in Dorchester County, Maryland. In combination with a tide and precipitation gage, a representative section of the marsh was instrumented with surface-water monitors and shallow groundwater piezometers to...
Walker, Charles W.; Lester, Todd R.; Nealen, Christopher W. Toward explaining nitrogen and phosphorus trends in Chesapeake Bay tributaries, 1992-2012
Understanding trends in stream chemistry is critical to watershed management, and often complicated by multiple contaminant sources and landscape conditions changing over varying time scales. We adapted spatially-referenced regression (SPARROW) to infer causes of recent nutrient trends in Chesapeake Bay tributaries by relating observed fluxes...
Ator, Scott; Garcia, Ana; Schwarz, Gregory; Blomquist, Joel; Sekellick, Andrew
Drought forecasting for streams and groundwaters in northeastern United States
BackgroundWhen rainfall is lower than normal over an extended period, streamflows decline, groundwater levels fall, and hydrological drought can occur. Droughts can reduce the water available for societal needs, such as public and private drinking-water supplies, farming, and industry, and for ecological health, such as maintenance of water...
Austin, Samuel H.; Dudley, Robert W.
Spatial and Temporal Patterns of Best Management Practice Implementation in the Chesapeake Bay Watershed, 1985–2014
Efforts to restore water quality in Chesapeake Bay and its tributaries often include extensive Best Management Practice (BMP) implementation on agricultural and developed lands. These BMPs include a variety of methods to reduce nutrient and sediment loads, such as cover crops, conservation tillage, urban filtering systems, and other practices....
Sekellick, Andrew J.; Devereux, Olivia H.; Keisman, Jennifer L.D.; Sweeney, Jeffrey S.; Blomquist, Joel D. The complex spatial distribution of trichloroethene and the probability of NAPL occurrence in the rock matrix of a mudstone aquifer
Methanol extractions for chloroethene analyses are conducted on rock samples from seven closely spaced coreholes in a mudstone aquifer that was subject to releases of the nonaqueous phase liquid (NAPL) form of trichloroethene (TCE) between the 1950's and 1990's. Although TCE concentration in the...
Shapiro, Allen M.; Goode, Daniel J.; Imbrigiotta, Thomas; Lorah, Michelle M.; Tiedeman, Claire
Annual wastewater nutrient data preparation and load estimation using the Point Source Load Estimation Tool (PSLoadEsT)
The Point-Source Load Estimation Tool (PSLoadEsT) provides a user-friendly interface for generating reproducible load calculations for point source dischargers while managing common data challenges including duplicates, incompatible input tables, and incomplete or missing nutrient concentration or effluent flow data. Maintaining a consistent...
Gorman Sanisaca, Lillian E.; Skinner, Kenneth D.; Maupin, Molly A. Bank‐derived material dominates fluvial sediment in a suburban Chesapeake Bay watershed
Excess fine sediment is a leading cause of ecological degradation within the Chesapeake Bay watershed. To effectively target sediment mitigation measures, it is necessary to identify and quantify the delivery of sediment sources to local waterbodies.This study examines the contributions of sediment sources within Upper Difficult Run, a...
Cashman, Matthew J.; Gellis, Allen; Gorman Sanisaca, Lillian; Noe, Gregory B.; Cogliandro, Vanessa; Baker, Anna
Geomorphic characteristics of Tenmile Creek, Montgomery County, Maryland, 2014–16
Data collected from April 2014 through September 2016 were used to assess geomorphic characteristics and geomorphic changes over time in a selected reach of Tenmile Creek, a small rural watershed near Clarksburg, Maryland. Longitudinal profiles of the channel bed, water surface, and bank features were developed from field surveys. Changes in cross...
Doheny, Edward J.; Baker, S. Matthew
Manure and fertilizer inputs to land in the Chesapeake Bay watershed, 1950–2012
Understanding changing nutrient concentrations in surface waters requires quantitative information on changing nutrient sources in contributing watersheds. For example, the proportion of nutrient inputs reaching streams and rivers is directly affected by when and where those nutrients enter the landscape. The goal of this report is to contribute...
Keisman, Jennifer L.D.; Devereux, Olivia H.; LaMotte, Andrew E.; Sekellick, Andrew J.; Blomquist, Joel D.
Monitoring the water-quality response of agricultural conservation practices in the Bucks Branch watershed, Sussex County, Delaware, 2014–16
The purpose of this study was to evaluate the effects of irrigation and cover crops as conservation practices on water quality in groundwater and streams. Bucks Branch, a stream in the Nanticoke River watershed in southwestern Delaware, was identified as having one of the highest concentrations of nitrate in all surface-water sites sampled by the...
Denver, Judith M.; Soroka, Alexander M.; Reyes, Betzaida; Lester, Todd R.; Bringman, Deborah A.; Brownley, Michael S.