Mill Creek Lake IA 06-LSR-1616

Assessment Comments

Monitored in 1990 by ISU as part of the Clean Lakes Classification Study (1994).

Basis for Assessment

Both fishable and swimmable uses were assessed as FST for the following reasons:  (1) results of monitoring show that average levels of secchi depth, chl-a, total-P, and TSS are better than overall averages for the 116 SPOLs sampled in 1990 and 1992; (2) lake does not have problems with fishkills; (3) levels of usage for both fishing and swimming are relatively high.  Support of uses is threatened by agricultural NPS:  lake has relatively high sedimentation rate (9.5 cm/yr) and very short life expectancy (16 years); presence of two sedimentation dikes, however, may alleviate sediment problems and extend the life of the impoundment.   Lake suffers from an unfavorable watershed: lake area ratio (123:1) and shallow mean depth (1.5m).