2.2 ASSESSMENT OF WATERSHED PROCESSES
2.2.1 THE NONPOINT SOURCE MANAGER'S GUIDE TO WATER QUALITY AND
LAND TREATMENT MONITORING
Problem definitions are based on the designated use of the water resource. This section will
discuss designated uses and how pollutants and conditions can threaten a use or impair a use. Please
refer to the report "The Nonpoint Source Manager's Guide to Water Quality and Lane Treatment
Monitoring" at the end of this chapter.
2.2.2 DATA ANALYSIS
220.127.116.11 Linking Water Quality Trends with Land Treatment Trends: The Rural Clean Water
Land use and land management affect the type and amount of nonpoint source (NPS) pollution
entering water bodies. Improvements in land management (also referred to as land treatment) are
necessary to reduce the delivery of pollutants to impaired or threatened water resources.
Documentation of the magnitude of water quality improvements from changes in land management, for
at least a few projects in each part of the country, is essential to provide feedback to project
coordinators and state, regional, and national policy makers. Such feedback enhances the development
and implementation of land treatment programs that effectively reduce delivery of pollutants causing
water quality impairment. In addition, demonstration that land treatment is effective in reducing NPS
pollution and improving water quality tends to increase political and economic support for NPS
pollution control measures.
Historically, it has been difficult to demonstrate the relationship between land treatment and
water quality changes, at least in part because of a lack of well-designed water quality and land
treatment monitoring efforts. Two goals must guide the design of monitoring networks and data analysis
in programs and projects designed to link water quality changes with implementation of best
management practices (BMPs): 1) detection of significant (or real) trends in both water quality and land
treatment and 2) linking or associating water quality trends with land treatment trends.
This fact sheet outlines the principles for development of effective monitoring designs, and
describes the land treatment and water quality monitoring elements necessary for linking land treatment
or land use modifications with water quality changes. These monitoring elements are essential for
successful experimental watershed projects designed to document the relationship between land
treatment and water quality changes.
Many of the recommendations for monitoring discussed in this fact sheet are based on the 15-year
Rural Clean Water Program (RCWP), an experimental, agricultural watershed, NPS pollution control