Description
In 2002, Hardwood Creek was listed on Minnesota's 303(d) List of Impaired Waters, for biological impairment resulting from a low fish index of biotic integrity (IBI). In 2004, Hardwood Creek was again listed on Minnesota's 303(d) List of Impaired Waters, for biological impairment, this time due to low dissolved oxygen (Table 1). Due to the fact that both TMDLs are intrinsically linked, a TMDL study was conducted that encompassed both impairments. Through the stressor identification process, the primary causes of the low IBI in Hardwood Creek were identified as sedimentation and low DO. The TMDL for the biological impairment is based on total suspended solids (TSS) loads, which address sedimentation. Various candidate mechanisms affecting DO were identified and ultimately may all play a role in DO levels to varying degrees. However, the low DO TMDL focuses on biochemical oxygen demand (BOD) loading, which was identified as a significant stressor during 2004. Therefore the TMDL for the low DO is based on BOD loads.
Date Issued
2009-07
Number of Pages
37
Decade
Associated Organization
Publisher
Minnesota Pollution Control Agency (St. Paul, Minnesota)
Main Topic
Keywords
Publication Series
Status
Body of Water
County
Format
Rights Holder
Minnesota Pollution Control Agency
Rights Management
Public Domain