ABSTRACT

The Delaware River Basin Commission is charged with establishing water-quality objectives for the tidal and non-tidal portions of the Delaware River, which include developing nutrient standards that are scientifically defensible. The U.S. Geological Survey, in cooperation with the Delaware River Basin Commission and the Academy of Natural Sciences, studied the effects of nutrient enrichment in the upper, middle, and lower sections of the non-tidal Delaware River. Algal samples were collected from the natural habitat using rock scrapes and from the artificial nutrient enrichment samplers, Matlock periphytometers. The knowledge gained from this study is to be used in helping determine appropriate nutrient criteria for the Delaware River in the oligotrophic, mesotrophic, and eutrophic sections of the river and is a first step toward gathering data that can be used in selecting nutrient effect levels or criteria thresholds for aquatic-life use protection. This report describes the methods for data collection and presents the data collected as part of this study.

First posted February 10, 2011