Publications

An assessment of ambient toxicity of Delaware public peninsula creeks where agriculture is the dominant land use. The assessment evaluates potential persistent impacts and potential intermittent or pulsed impacts. Three watershed assessments have plastic culture practices.

This workshop was held to cover the topic of Sedimentsheds. sedimentshed is a new concept, and is defined as the area that contributes the sediment which directly influences water clarity in near-shore Submerged Aquatic Vegetation (SAV) grow zones.

Download publication‍

Chesapeake Bay watershed model precipitation and meteorological data development and atmospheric nutrient deposition.

Download publication‍

The Chesapeake Bay Groundwater Toxics Loading Workshop was held April 15-16, 1992, at the U.S. EPA Chesapeake Bay Program Office. Workshop participants reviewed and discussed available information on results from groundwater studies and developed a strategy to provide a firs order estimate of the magnitude of groundwater loads of toxic substances to Chesapeake Bay and its tidal tributaries. The participants also recommended that groundwater loads of nutrients should be assessed concurrently with the toxic substance loads.

Download publication‍

This report summarizes the findings of the workshop. The first objective of the workshop was to determine connections between issues, programs, agencies, organizations, and jurisdictions to advance their abilities to address atmospheric nitrogen issues. The second objective was to identify platforms for discussion of solutions, and the last objective was to determine research and policy work needed to advance the understanding of ecosystem impacts of nitrogen in the air and watershed.

This study was performed to compare standard EPA techniques for determining nitrogen and phosphorus concentrations in natural waters with oceanographic techniques typically employed by estuarine and marine scientists.

Download publication‍

Eutrophication -- low dissolved oxygen -- caused by excess nutrients, is the most significant water quality problem facing the Bay. The Chesapeake Bay Program jurisdictions have committed to reduce nitrogen and phosphorus pollution reaching the Bay by 40 percent from 1985 levels by the year 2000. This report addresses the cost effectiveness of various control options. This is an archived document.

Appendix F documents in detail the Phase IV Chesapeake Bay Watershed Model point source nutrient data assimilation process for the facilities located in signatory and non-signatory jurisdictions of the Chesapeake Bay Watershed. This document includes a description of the data sources, the methods of assimilation, types of analysis performed to determine nutrient reduction estimates, and trends in nutrient loadings discharged to the Chesapeake Bay Watershed. The Phase IV Watershed Model Point Source Database includes information for approximately 612 (the exact number varying depending on the year) active industrial, municipal, and federal facilities discharging directly to surface waters within the Chesapeake Bay watershed from all signatory and non-jurisdictions including: New York, Pennsylvania, Maryland, Delaware, District of Columbia, Virginia and West Virginia. Facility information, and flow and loading data are included for each of the 612 facilities for the years 1985 through 1996, 2000, Tributary Strategy Implementation (which is expected to occur after the year 2000) and additional nutrient reduction scenarios. The following flow and loading parameters are included: flow, total nitrogen, nitrate, organic nitrogen, total phosphorous, phosphate, organic phosphorous, biochemical oxygen demand, and dissolved oxygen.The nutrient point source loading data can be presented in both loads discharged at end of pipe and loads delivered to the Chesapeake Bay. To determine delivered loads, delivery factors were applied to the discharged loads to estimate attenuation as loads travel down the tributaries to the mainstem of the Chesapeake Bay. The total nitrogen load delivered to the Chesapeake Bay has decreased by 14 percent from 1985 to 1996, and is expected to decrease 27 percent from 1985 to 2000, and 33 percent from 1985 and Tributary Strategy Implementation (after 2000). These reductions are primarily due to facilities implementing biological nitrogen removal. The total phosphorous load delivered to the Chesapeake Bay has decreased 50 percent from 1985 to 1996, and is expected to decrease 55 percent from 1985 to 2000.

Download publication‍

Available in digital format and hardcopy. The Scientific and Technical Advisory Committee (STAC), in cooperation with the USDA and the Mid-Atlantic Water Quality Program, convened a forum on innovation in agricultural conservation in May 2003. Leading experts on various aspects of agricultural nutrient pollution control from the Bay region and beyond discussed current, emerging, and future practices, technologies, and policies that can help to achieve needed nutrient reduction goals within a sustainable agricultural system. Twenty-eight speakers and discussion leaders provided their vision for innovation, while discussion among scientists, engineers, economists, and practitioners broadened and diversified the vision. The forum included factors that influence the adoption of innovation and policies and approaches to implementing innovation. This White Paper identifies emerging science-based practices, programs, and policies that can be implemented within three years as well as developing efforts that will aid nutrient reduction within a 10-year timeframe, including the research and education necessary for that implementation.

Download publication‍

A continuous deterministic environmental model of the Chesapeake Bay Watershed (HSPF), linked to an atmospheric deposition model (RADM) is used to examine nutrient loads to the Chesapeake Bay under different management scenarios. Model structures and calibration are generally described. Averaged over a ten-year simulation, loads under a limit-of-technology setting throughout the watershed are a 50% and 65% reduction from loads reflecting 1985 condition and in total nitrogen and total phosphorus, respectively. Urban loads which include discharges from point sources, on-site wastewater, disposal systems, combined sewer overflows and both pervious and impervious non-point sources, have the highest nutrient fluxes to the Chesapeake Bay among major land uses.

Download publication‍