Municipalities, regulatory agencies, and resource advocacy organizations are often tasked with the enormous responsibility of monitoring water quality and implementing management strategies for vast areas within their jurisdictions. A potential means for addressing the resulting sampling shortfall is the use of volunteer monitoring programs. The project reported herein demonstrates the use of Q...

SWAT (Soil and Water Assessment Tool) is a watershed model that has been incorporated into USEPA’s modeling framework called BASINS used for total maximum daily load (TMDL) analysis. It is thus important that SWAT realistically simulate tile flow and pothole landscapes that are common in much of the Corn Belt and Great Lakes states. In this study, SWAT was modified to simulate water table dynam...

Overview: Coastal embayments throughout the State of Massachusetts (and along the U.S. eastern seaboard) are becoming nutrient enriched. The nutrients are primarily related to changes in watershed land-use associated with increasing population within the coastal zone over the past half century. Many of Massachusetts' embayments have nutrient levels that are approaching or are currently over the...

SWAT is a GIS-based basin-scale model widely used for the characterization of hydrology and water quality of large, complex watersheds; however, SWAT has not been fully tested in watersheds with karst geomorphology and downstream reservoir-like embayment. In this study, SWAT was applied to test its ability to predict monthly streamflow dynamics for a 1,555 ha karst watershed, Chapel Branch Cree...

The U.S. Environmental Protection Agency (EPA) has reported that over 45 percent of the nation's waterbodies are impaired and has identified nonpoint sources as the major contributors to water quality problems. Although federal and state government agencies have largely controlled pollution from point sources through infrastructure grants and permit programs, few statutes and regulations target...

External loading of phosphorus (P) from agricultural surface discharge (tailwater) is the main cause of excessive algae growth and the eutrophication of the Salton Sea, California. Continuous polyacrylamide (PAM) applications to agricultural irrigation water inflows were evaluated as a means of reducing sediment and P in tailwater. Zero (control) and 1 mg L PAM (PAM1) treatments were compared a...

Management of the quality of the Nation’s water requires large quantities of information describing current conditions and related environmental factors. Such information is expensive to collect and difficult to interpret over large scales. To support the efficient use and interpretation of available water-resource information, the U.S. Geological Survey (USGS) developed a spatial water-quality...

Water quality in mountain streams of the southern Appalachians varies seasonally and with storms. In an effort to validate Total Maximum Daily Loads (TMDLs) for sediment in the Chattooga River Watershed (NE Georgia, NW South Carolina, and SW North Carolina), we studied four tributary streams over an eighteen-month period. Two of the streams had completely forested watersheds; one stream was a b...

The Soil Water Assessment Tool (SWAT) was implemented to determine annual sediment yields and critical source areas of erosion for the Buffalo River Watershed. Model calibrations were performed by comparing simulated streamflow discharge and sediment concentrations against measured values. Monte-Carlo simulations were performed to identify the most sensitive parameters and the “best-fit” parame...

Nitrogen often is the limiting nutrient for the growth of algae and phytoplankton in estuaries and surface waters in California. To control cultural eutrophication (i.e., excessive growth of algae and plankton related to anthropogenic sources) regulatory agencies often focus on the control of point source discharges, including municipal wastewater effluent. Recent attempts to control cultural e...