Rivers at Risk in S.D.

A record level of new federal funding will help the Lewis & Clark Regional Water System expand and provide more drinking water to southeastern South Dakota. The expanded system will be better equipped to provide clean water from the Missouri River to the greater Sioux Falls region, even with continued population growth and extended drought conditions.

South Dakota’s native freshwater mussels clean the water in state rivers and streams, but agricultural pollution and habitat destruction appear to be reducing their numbers at the same time the invasive, non-native zebra mussels spreading throughout South Dakota are a new threat to aquatic populations. Experts wonder if state and federal wildlife and environmental protection agencies are doing enough to protect native freshwater mussels.

South Dakota farmers and ranchers -- many hurting from low commodity prices -- say the state's current system of ag land valuation and taxation places an unfair financial burden on them at a time they can least afford it. Ongoing efforts to reform the system, however, would likely raise taxes on homes and businesses or leave school districts and counties with fewer revenues.

About 900 gallons of Roundup weed-killer and other chemicals flowed into the river near Estelline in late June; so far, officials predict no lingering impacts.

The Agropur plant in Lake Norden may face fines over effluent violations just three months after a $252 million expansion that shifted wastewater directly to the Big Sioux River.

Taxpayers could face millions in mitigation costs and restrictions on boaters could rise due to invasive mussel infestation recently discovered on second Missouri River reservoir.

A mandatory effort in Minnesota shows regulation can be effective in reducing agricultural runoff. But some say a regulatory approach is unnecessary, citing progress in South Dakota with volunteer methods.

Repairing and replacing aging, overworked treatment plants is an important step in improving the quality of South Dakota rivers, some of which provide drinking water for communities. But costs would fall largely to residents.

Researchers say waterways contain genetic markers for potentially deadly strain of E.coli. In addition, decades-old mining runoff continues to raise arsenic levels in Cheyenne River.

Most attempts to mitigate damage from runoff of agricultural operations and urban construction are voluntary in South Dakota. Few farmers and contractors opt to use sometimes costly pollution-control processes.