If you need further evidence of the sometimes cartoonish level of ham-fisted management of environmental regulatory matters by the federal government, consider the proposal by the Environmental Protection Agency to change the definition of “navigable waters” under the Clean Water Act.

A coalition of over 30 business organizations led by the Arizona Chamber of Commerce and Industry recently submitted comments in response to a rule proposed by the EPA and the Army Corps of Engineers that could have a dramatic and negative effect on Arizona’s economy.

Under the EPA plan, there’s no telling what economic harm could be inflicted on the state by changing the definition of “waters of the United States,” since vast areas of Arizona would come under federal government jurisdiction for the first time. Existing federal law requires agencies to gather feedback from affected stakeholders – in this case farmers, ranchers and other businesses – in the rulemaking process to ensure potential economic impacts of a rule are fully understood. There was no such engagement process this time around. Instead the EPA simply said its proposal would “not have a significant economic impact,” cold comfort for businesses in Arizona facing a rule that would place new regulatory burdens on canals, ditches and other private property.

This is no small change that the feds are mulling. According to an analysis performed by the Central Arizona Project and the L. William Seidman Research Institute at ASU, CAP alone generated $1 trillion of Arizona gross state product from 1986-2010. That the administration did not engage in a robust consultation with affected stakeholders in an area that plays such an integral role in Arizona’s economic health would be unfathomable if it weren’t for the fact that we’ve become used to the feds’ mismanagement of federal-state environmental issues.

Arizona in just the last few years has seen its share of federal highway dollars put at risk as it battled with the EPA over the effect seasonal dust storms have on air quality readings in Maricopa County, and we’ve seen the future of the Navajo Generating Station jeopardized as part of a manufactured crisis over haze at our national parks that was really a proxy in the administration’s hardline against coal. Now we’re facing a proposed rule that would treat washes that fill with water only after big storms as navigable waterways and place them under federal regulation.

Arizona knows water management. To grow a vibrant economy in an arid desert is a remarkable feat that takes the dedication of committed professionals who understand fully the scarcity of water here.  CAP and our utilities around the state are leaders in water stewardship. But now Washington, D.C. bureaucrats are telling Arizona how to manage its water, using questionable science and far overstepping their authority under the Clean Water Act.

Arizona’s congressional delegation deserves credit for keeping a close eye on this. Senators John McCain and Jeff Flake last week sent a strong letter to the EPA raising serious questions over the scientific basis for the proposed regulatory expansion, and Reps. David Schweikert, Paul Gosar, Trent Franks and Matt Salmon in June convened a hearing in Phoenix to field concerns over the rule.

No one doubts the importance of properly managing our water supply or the necessity of revisiting the Clean Water Act from time to time to ensure its effectiveness. But the latest proposed rule by the EPA needs to go back into the shop. If the agency wants to better understand Arizona’s unique water landscape, it can start by ensuring Arizonans are at the table the next time it develops such a far-reaching proposal.

Glenn Hamer is the president and CEO of the Arizona Chamber of Commerce and Industry, which is committed to advancing Arizona’s competitive position in the global economy by advocating free-market policies that stimulate economic growth and prosperity for all Arizonans.