Impact/Purpose:

The objective of this study is to gather general data and information that will aid in determining if it is necessary to develop a more thorough assessment of the naturally-occurring levels of dissolved oxygen (DO) and concurrent conditions that support healthy, unimpaired biological communities in blackwater streams. This study is designed to determine what taxa comprise the benthic macroinvertebrate community under two different sets of sample conditions. This study is not designed to determine what DO levels should be maintained in blackwater streams. The study was requested by R4 Water Management Division, Standards Monitoring and TMDL Branch.

Description:

The limited availability of data pertaining to naturally occurring levels of dissolved oxygen (DO) in blackwater stream reduces the ability of both EPA and the States to make assessment decisions and evaluate the appropriateness of the existing criteria for blackwater streams. The data collected during this study will support the R4 Water Management Division’s need to better understand what levels of DO naturally occur in and support a healthy biological community in blackwater streams. Based upon the data and information collected in this study, a more thorough study may be developed to assess what the naturally occurring levels of DO are in blackwater streams. The data collected at each site during each phase of the study include the following: hourly measurements of DO, pH, temperature, conductivity, and turbidity; weekly measurements of nutrients and total organic carbon (TOC); and, a monthly sample of benthic macroinvertebrates, tannin and lignin, chlorophyll a, and algal growth potential.

Record Details: