South Dakota's Republican members of Congress are apparently determined to prevent water regulations from becoming their Waterloo.

Like the French emperor Napoleon Bonaparte at the famous 1815 battle of that name, Sen. John Thune and Rep. Kristi Noem realize that if they're defeated, it could be their end. So, they launch strikes against the federal Environmental Protection Agency every chance they get. Lately, they've been critical of an EPA move to gain greater clean water regulatory power (as of last week, Sen. Tim Johnson, D-S.D., had not publicly opined on it).

The plan would allow the EPA to regulate seasonal and rain-dependent streams, and wetlands near rivers and streams, while other ponds and streams would be considered on a case-by-case basis to determine if they play a significant role in the quality of downstream waters.

In their assault on the proposal, Thune and Noem are backed by an army of agricultural lobbyists who are concerned that agricultural runoff -- from pesticides, fertilizers and the like -- might come under greater scrutiny.

We're all for South Dakota's elected officials standing up for South Dakota, but they tend to suffer from blinders when an issue pits agricultural interests against federal regulations. While getting riled up about the potential costs to farmers -- who are now reaping the benefits of the best ag economy in modern history -- our politicians tend to ignore the costs of inadequate regulation, including polluted water.

If you don't trust the EPA, take it from South Dakota's own Department of Environment and Natural Resources. It assessed South Dakota waterways from 2008 to 2013 and rated 94 rivers, streams or segments, and also 72 lakes, as "impaired." Impaired waterways are too polluted to support certain beneficial uses, possibly including irrigation, fish propagation, recreation, domestic water supply, livestock watering and more.

Who or what is to blame? Carefully read this highly technical quote from The 2014 South Dakota Integrated Report for Surface Water Quality Assessment, issued by the DENR in March:

" ... Nonsupport for fishery/aquatic life uses was caused primarily by total suspended solids (TSS) from agricultural nonpoint sources and natural origin. Nonsupport for recreational uses was primarily caused by fecal coliform and Escherichia coli (E. coli) contamination from livestock and wildlife contributions."

Translation: Agricultural sources, while not solely to blame, are a significant contributor to water pollution in South Dakota. That's according to South Dakota's own regulators.

We don't want to overburden farmers with regulations. But if an industry has a role in polluting water, the offending industry should bear a reasonable level of responsibility and should work with regulators to address the problem.

To reject any and all efforts by the EPA to further clean up public waters may be politically expedient for politicians who rely on the agricultural industry for campaign contributions and votes, but it's detrimental to the environment and everybody else who collectively owns and uses those waters.

We wish our elected officials would take a common sense approach, realizing that everybody needs and wants clean water and that some kind of balance between regulation and freedom is best -- not rigidly protected immunity for politically important offenders.