Iowa DNR

Water Quality Assessments

Impaired Waters List

Shell Rock River IA 02-SHL-783

from south corporate limit of Shell Rock (S12 T91N R15W Butler Co.) to confluence with Flood Cr. in S27 T93N R16W Butler Co.

Assessment Cycle
Result Period
1996 - 1998
Assessment Type
Not Assessed
Integrated Report
Category 0
Legacy ADBCode
IA 02-SHL-0010_2
Overall Use Support
Not assessed
Aquatic Life Use Support
Not assessed
Fish Consumption
Not assessed
Assessment Comments

Not assessed.

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses and the fish consumption uses are considered "not assessed."  EXPLANATION:  The DNR quarterly water quality monitoring station on the Shell Rock River at Shell Rock, upon which previous assessments of the Class B(WW) uses have been based, has not been monitored since the 1992-93 biennial period.   These data are now considered too old (greater than five years) for developing a valid assessment of support of the Class B(WW) uses.   In addition, the special water quality studies of dissolved oxygen levels conducted for the proposed hydropower project at Greene were conducted in 1994 and are now too old to be useful for characterizing current water quality conditions.   As part of DNR's expanded water quality monitoring program, monthly monitoring began at the Shell Rock station in October 1999.   Results from this monitoring will allow development of an updated assessment of support of beneficial uses for the 2002 report.   Fish consumption uses were considered "not assessed."  The most recent fish tissue monitoring was conducted in 1990 near Clarksville, and the results from this monitoring are too old for developing an assessment of current support of the fish consumption uses.