Nutrient, Sediment, and Flow

The goal of the IAN seminar series is to provide concise, thought-provoking ideas relating to Chesapeake Bay science and management.

This web site is dedicated to providing water-quality load and trend results for the nontidal rivers of the Chesapeake Bay watershed.

Changes in nitrogen, phosphorus, and suspended-sediment loads in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Water-Quality Monitoring Network (NTN). These results are used to help assess efforts to decrease nutrient and sediment loads being delivered to the bay. Additional information for each monitoring station is...

Changes in nitrogen, phosphorus, and suspended-sediment loads in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the nine Chesapeake Bay River Input Monitoring (RIM) stations.

Prepared by Allen C. Gellis and John W. Brakebill, U.S. Geological Survey (March 2013)

USGS scientists have determined that high-salinity groundwater found more than 1,000 meters (0.6 mi.) deep under the Chesapeake Bay is actually remnant water from the Early Cretaceous North Atlantic Sea and is probably 100-145 million years old. This is the oldest sizeable body of seawater to be identified worldwide.

During the past 10 years, integrated studies of sediment in Chesapeake Bay and its tributaries have been carried out by a team of USGS scientists, in collaboration with researchers from several universities, the Maryland Geological Survey, the U.S. Naval Research laboratory, the USEPA, and other institutions. The USGS worked with these investigators to prepare a comprehensive review of sediment...

High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...

Access the most recent data gathered from the Chesapeake Bay Nontidal Monitoring Network, learn about the techniques used to collect this data, and read about the history of the Chesapeake Bay Nontidal Monitoring Program. Nontidal Network (NTN) data refers to data from the 123 monitoring stations where nutrients and sediment are collected monthly and during storms. River Input Monitoring (RIM)...

The USGS has completed more enhancements to our innovative technique to assess water-quality trends. The WRTDS (Weighted Regressions on Time Discharge and Season) method was first published in 2010 as an exploratory data analysis technique for understanding trends in surface water. Subsequently, we published the EGRET (Exploration and Graphics for RivEr Trends) software which implements the WRTDS...

USGS results on phosphorus trends reveal little progress over the past decade. USGS results show phosphorus trends over the past decade do not show improving conditions at a majority of the sites. Water-quality managers call for more actions to increase progress.

As the largest and most productive estuary in North America, Chesapeake Bay is a vital ecological and economic resource. In recent decades, however, the bay and its tributaries have been degraded by excessive inputs of nutrients (nitrogen and phosphorus) and sediment from contributing watersheds, and in 1998, the Chesapeake Bay and its tidal tributaries were listed as “impaired” under the Clean...