Ringo H.W. Chiu, Associated Press
Homes with swimming pool are seen, Thursday April 2, 2015 in Altadena, Calif.

For the first time in its history, California is implementing mandatory water restrictions in the face of the Golden State’s record-breaking drought. California Gov. Jerry Brown has proposed a number of water-saving measures designed to cut overall consumption by 25 percent.

However, one measure that could have a profoundly positive effect was not mentioned in Brown’s plan. Californians could save a great deal of water by not growing so much marijuana. The same could be said in each Western state now suffering from a dwindling supply of water.

Such is the conclusion of a study recently published by the Public Library of Science journal, which found that California’s marijuana farms are “unsustainable.” The study notes the explosion of marijuana growth since California legalized medical marijuana in 1996 has resulted in “surface water diversions for irrigation resulting in reduced flows and completely dewatered streams.” This is also doing tremendous damage to fish populations. Quoting again from the study: “Continued diversions at a rate necessary to support the current scale of marijuana cultivation in northern California could be catastrophic for aquatic species.”

Yet even though marijuana uses so much of the state’s increasingly rare water supplies, California authorities do not currently regulate marijuana farming. It is only now, in the face of unprecedented water shortages, that the California Water Resources Control Board is developing a permit process for 10 northern California counties where marijuana farming is most prevalent. Yet that seems to be a tepid response to a serious problem. The marijuana industry has long been the province of lawbreakers, and it seems unlikely that those who have been conducting their business without any legal oversight would readily adopt measures to protect the California environment from the impact of their actions.

It is worth noting that Utah also has a problem with illegal marijuana farms. News reports have said these remote operations, mainly in southern Utah, pose dangers to law enforcement as well as innocent hikers who may stumble upon them. Much of what is grown here is for export to other states. But with Utah also in the throes of a major drought, it follows that these farms pose a risk to water supplies, as well.

The drought threat is just the latest evidence that medicinal and recreational marijuana laws cause more problems than they solve. Federal law still prohibits marijuana cultivation, although Washington now seems loath to enforce the law in the face of legalization efforts in some states.

Unfortunately, the politically correct sentiment in many quarters is that marijuana is a harmless drug. This draws attention away from marijuana’s very real and deleterious health effects, which include lung problems, short-term memory loss, and increased risk of psychosis, delusions and paranoia.

But the environmental effects during a time of severe and unrelenting drought are much harder to ignore. The choice between a marijuana high and water to drink is really no choice at all.