Critical Periods of Pollutant Loading
Project Number: BQY32
Project Chief: David J. Graczyk; Steven R. Corsi
Project Topics: xxxc
Cooperators: Wisconsin Department of Natural Resources
Period of Project: October 2005–September 2007
Non-point Evaluation Monitoring Studies team member Judy Horwatich (right) discusses ongoing work with area residents.
The distribution of daily constituent loading throughout the year is important for design and evaluation of best-management practices. Is most of the annual constituent load generated by snowmelt runoff during a few days in the spring of the year or is most of the annual constituent load generated by intense thunderstorms during the summer? How much does the distribution of daily constituent load vary from year to year and from site to site? Does the portion of the annual constituent load vary seasonally from year to year and from site to site?
The objectives of the study are to: (1) determine the cumulative distribution of daily constituent loadings and examine the differences over time and between sites and (2) determine the seasonal distribution of annual loads.
Daily constituent loads from the evaluation monitoring sites will be used as the data set. Loads have been calculated at 8 rural evaluation monitoring sites with 6-8 years of data at each site. The cumulative distribution of daily constituent loadings will be determined for each site and for each year. The portion of annual load attributed to seasons selected will be determined and compared over time and between sites.
Data were compiled for the eight rural evaluation-monitoring sites. Cumulative distribution of daily constituent loadings for each site and year was determined.
Analyses will continue and preparation of a report will begin. Results will be published as a U.S. Geological Survey Open-File Report.
Publications and Reports
Results will be published as a U.S. Geological Survey Open-File Report.