President Donald Trump’s war on clean water regulations could end up benefiting something near and dear to his heart — and his bank account: the dozen golf courses he owns in the U.S.

Trump last month signed an executive order calling on the Environmental Protection Agency to issue a review of the Clean Water Rule, also known as the Waters of the United States rule. The rule, which Barack Obama instituted in 2015, designates many smaller creeks and wetlands as protected under the Clean Water Act of 1972, meaning landowners are required to protect such bodies of water from pollution.

Builders, farmers and golf course owners — via their lobbying group, Golf Course Superintendents Association of America — have fought the Obama rule, calling it federal “overreach.” They say they don’t want to be saddled with the extra costs of keeping smaller bodies of water on their land clean, even though environmentalist say they feed into larger water systems depended on by the public.

Trump’s push against the rule raises yet another concern about his conflicts of interest in his dual role as both president and business owner. (Bloomberg points out that the golf association includes 20 Trump employees.) Critics worry that Trump is considering what’s good for the bottom line at his golf courses, rather than what’s good for the country.

“This conflict is disturbing and his failure to completely step away from his business raises questions about his White House actions,” Scott Amey, general counsel for the Project on Government Oversight, told The Associated Press.

When Trump signed the executive order calling for the regulation to be reconsidered, he blasted the rule as “horrible” and called it a sign that federal regulation had “truly run amok.”

Trump’s order to “rescind or revise” the rule could take years because some replacement would have to be drafted. The Obama regulation is currently being challenged in court and hasn’t taken effect yet.

Things could get hairy for the commander in chief and the golf course owner-in-chief when water use becomes a critical issue. Golf courses, especially those in hot climates like Trump’s Mar-A-Lago resort, require extraordinary amounts of water to keep the greens green. And, unlike farmland, they don’t help feed the population. Golf courses in the U.S. drank up some 2.08 billion gallons of water per day for irrigation in 2015, Inside Science reported.

Trump doesn’t appear to be the kind of golf course owner concerned about water conservation. He blasted the “horrible look” of the Pinehurst Resort course in North Carolina during the 2014 U.S. Open. The club had cut back on irrigation as part of its drive to reduce water use.

I'd bet the horrible look of Pinehurst translates into poor television ratings. This is not what golf is about! — Donald J. Trump (@realDonaldTrump) June 15, 2014