Arbor Lake IA 03-NSK-864

Assessment Comments

Assessment is based on results of water quality monitoring and surveys by IDNR Fisheries Bureau.

Basis for Assessment

Both fishable and swimmable uses were assessed as "not supported" (NS) for the following reasons:  (1) Bachmann et al.  (1994) make the following statements regarding Arbor Lake:  "There are frequent algal blooms and siltation is a serious problem.   Because of the poor water quality, the fish are unfit to eat and swimming is prohibited."  Monitoring in 1990, however, suggests that the lake has approximately average WQ for Iowa SPOLs:  average levels of secchi depth and TSS are approx equal to or better than overall averages for the 116 SPOLs sampled in 1990 and 1992; average levels of chl-a and total-P are worse, but just slightly, than the overall averages.   The lake has a relatively high sedimentation rate (7.6 cm/yr) and rel.  short life expectancy (28 years) for SPOL impoundments.   Based on info in Bachmann et al., lake uses were assessed as NS.