surface water sites in eastern Iowa (see map below) were monitored on a
daily basis in order to evaluate the variability of selected parameters
through time in Iowa streams. The
variability of pesticides, nitrogen, phosphorus and bacteria was evaluated through a 90-day period including part or all of May, June,
July, and August, 2000. Sites that were monitored include Old Man's Creek near
Sharon Center (Johnson County), the English River at Riverside
(Washington County), and the Iowa River at Marengo (Iowa County).
In addition to sampling for common herbicides, water samples were
collected and sent to Aventis CropScience, where isoxaflutole
(Balance™) were analyzed and reported to the Iowa
Department of Natural Resources. Samples are analyzed for the parent compound of Balance and its two
addition to these three sites, the 60 monthly surface water sites were sampled for Balance
May, June, and July 2000.