Williamson Pond IA 04-LDM-1058

Assessment Comments

Assessment based on surveys by IDNR Fisheries Bureau.

Basis for Assessment

The Class A (primary contact recreation) uses remain "not assessed."  The Class B(LW) aquatic life uses remain assessed as "partially supported."  EXPLANATION:  The Class A uses remain "not assessed" due to the lack of recent water quality information upon which to base an assessments.   The Class B(LW) uses remain assessed as "partially supported" based previous assessments (see above).   This lake was part of the ongoing statewide survey of Iowa lakes conducted by Iowa State University in 2000.   This lake, however, was dry during 2001 and was not sampled.   Too few data are available from the sampling conducted in 2000 upon which to base an assessment of either the Class A or Class B(LW) uses.   The assessment category for the aquatic life uses of this lake ("evaluated") indicates that the assessment is based entirely on "best professional judgement."  In terms of Section 305(b) reporting, "evaluated assessments" are those based on data older than five years or other than site-specific ambient monitoring data (e.g., questionnaire surveys of fish and game biologists [=best professional judgement]) and thus have relatively low confidence.   IDNR does not consider waterbodies identified as "impaired" based on "evaluated assessments" as candidates for the state's Section 303(d) list.   In contrast, "monitored assessments" are based primarily on recent, site-specific ambient monitoring data and thus have relatively high confidence.   IDNR considers waterbodies identified as "impaired" based on "monitored assessments" as candidates for the state's Section 303(d) list.   Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring at this lake.