Implications of Applying Statistically Based Procedures for Water Quality Assessment

Abstract

Assessment of water quality conditions as required by Section 303d of the Clean Water Act must rely on limited monitoring data. Because data are limited there will always be the potential for error when deciding if water quality standards are being met. However, the informed use of statistical procedures makes it possible to describe and manage these errors. We make the case for using such procedures in water quality assessment and draw the implications for the monitoring data for water quality standard setting, arguing that standard setting must accommodate the limits of the monitoring data and the statistical procedures that will be used for water quality assessment.