Anoxia and Hypoxia in the Severn River, Chesapeake Bay

Abstract

Repeated observations have shown that water quality in bodies of water with developed coastlines and watersheds is often compromised. In this study water quality in the Severn River, a tributary to the Chesapeake Bay, was monitored to determine the extent of hypoxic and/or anoxic conditions. Fifteen sites were monitored weekly throughout the summer of 2008; temperature, salinity, and dissolved oxygen were measured as a function of depth at each site. A secchi depth measurement was also made to determine water clarity at each site. Differing degrees of hypoxia and anoxia were observed at each site. Some areas experienced prolonged anoxia due to natural conditions, but in other areas anoxia appeared to be related to runoff caused by development and poor land management, which ultimately adversely affected water quality. While it is difficult to restore damaged watersheds, better management of the Severn watershed could help maintain or restore water quality in the Severn River.