St. Louis River AOC Benthic Community Reference Sites


The objective of this study is to get information on the benthic community at "least impacted" sites within the St. Louis River AOC in support of removal of the Degradation of Benthos BUI. The BUI Target reads, in part, "The benthic community in historically degraded areas...of the AOC deos not significantly differ from unimpacted sites of comparable characteristics within the AOC.


Data on "least impacted" sites within the AOC to help define the benthic community structure and the variability expected in a benthic community within sites and between sites.

Study Design

Reference sites were selected based on previous work studying watershed impacts, and ground-truthing of the existing habitat quality on those sites (NRRI-GLEI, 2009). Five petite ponar samples will be taken at each of four sampling locations within each of four reference sites. The sampling locations will be spread along a transect between shallow vegetated habitat toward the deeper unvegetated habitat in that site. One of the replicates will be sent to the Wisconsin State Lab of Hygiene for total organic carbon and particle size analyses. Four of the replicates will be sent to the Lake Superior Research Institute for identification of the macroinvertebrates to the lowest taxanomic level practical. The replicates will be treated separately to allow for study of the variability within sites, while also allowing the replicates at each site to be pooled for other comparisons.

Related Reports

Run Project Summary Report
View Umbrella-Projects
View Related-Projects

Great Lakes Restoration Initiative
Toxics and Areas of Concern
Reports and Documents
Sediment tox of Benthos Reference sites and two others, SLH Lab Report FW000540-545
Technical Memo as part of LimnoTechs deliverable to MPCA for fieldwork portion of this project
WI-MN approved QAPP with appendices
Revision 1 - Approved version
Activities & Recommendations
Monitor AOC Beneficial Use Impairments
Complete a comparison of sample locations among and within reference sites.
Monitor AOC Beneficial Use Impairments
Analyses of samples for benthos, TOC and particle size
Monitor AOC Beneficial Use Impairments
Sample benthic community in reference locations within the AOC