The state D-N-R is investigating five separate fish kills, three on waterways in Sioux County and one each in Lyon and Keokuk counties. The longest of the kills extends for three miles of Willow Creek in Sioux County near Granville. D-N-R spokesman Kevin Baskins says the recent rains are likely to blame in the four cases in northwest Iowa. Baskins says that rainfall after it’s been dry for so long washes all of the concentrated matter on the landscape into streams, which are already lacking in water so there’s little dilution of the pollution. Four of the fish kills are in far northwest Iowa: on the West Branch of the Floyd River near Maurice in Sioux County, on Willow Creek in Sioux County near Granville, on Mud Creek near Doon in Lyon County and on the Floyd River in Sioux County near Hospers. Baskins says that region of the state got significant rain late last week.The fifth fish kill under investigation is on Coal Creek near What Cheer in Keokuk County. Baskins says there were some high levels of ammonia detected in the stream, but as of Tuesday afternoon, a source of the pollution had not yet been determined. While most of the fish kills were reported over the past few days, Baskins says there are new reports on the fish kill on the Floyd River in Sioux County near Hospers. He says they’re back on the scene today and investigators are continuing to follow a tributary upstream that may lead them to the source of the contamination. He says most of the incidents involve hundreds of dead fish but the one on Willow Creek near Granville in Sioux County involves thousands of fish. Since most of the kills are several days old, Baskins says it will be difficult to identify specific sources. He urges people who run across large numbers of dead fish to report it immediately.