West Fork Cedar River IA 02-WFC-801

Assessment Comments

Assessment is based on results of (1) IDNR ambient monthly monitoring at Finchford in 2000 & 2001.

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses are assessed as "fully supported."  Fish consumption uses remain "not assessed."  The source of data for this assessment is the results of IDNR ambient monthly water quality monitoring conducted on the West Fork Cedar River at Finchford during the 2000-2001 biennial period.   EXPLANATION:  None of the 24 samples collected during the 2000-2001 biennial period at the IDNR monthly station violated Class B(WW) water quality criteria for pH, dissolved oxygen, or ammonia-nitrogen; no violations occurred in the four samples analyzed for toxic metals or in the six samples analyzed for pesticides.   This river segment continues to demonstrate above average water quality conditions for Iowa rivers.   For example, only one of the 24 samples collected during the biennial period contained a detectable level of ammonia-nitrogen (maximum value of 0.20 mg/l on April 12, 2000).   Although monitoring conducted by USGS from 1996 to 1998 showed that one of 26 samples contained DDE above the Class B(WW) chronic criterion (see assessment for the 2000 report above), none of the six samples analyzed for DDE at the IDNR station during the 2000-2001 biennial period contained a detectable level of DDE.   Based on these results, the Class B(WW) aquatic life uses of this river segment are assessed as "fully supported."  Support of the fish consumption uses remains "not assessed" due to the lack of recent fish contaminant monitoring in this river reach.