Is Marijuana Destroying California’s Water and Wildlife?

The discussion over marijuana in California is a heated one, and not just because of THC.

Since 1996, marijuana has been legal in California for medical purposes, setting off an increase in marijuana cultivation. But while that’s good for the pro-marijuana crowd, it’s not as good for the pro-environment crowd. Why? California’s marijuana industry is having a serious affect on wildlife and water, now aggravated by the state’s worst-ever drought.

Proposition 215 was passed in 1996, and since then officials have recorded more and more streams going dry, even causing one country to outlaw personal grows. But officials hold that it’s not really personal growing that’s the problem. According to the AP, “State fish and wildlife officials say much of the marijuana being grown in northern counties under the state’s medical pot law is not being used for legal, personal use, but for sale both in California and states where pot is still illegal.”

That demand is in turn increasing supply, in the form of larger-scale marijuana farming, which is having a serious environmental effect.

“People are coming in, denuding the hillsides, damming the creeks and mixing in fertilizers that are not allowed in the U.S. into our watersheds,” Denise Rushing, a Lake County supervisor told the AP. “When rains come, it flows downstream into the lake and our water supply.”

The affected watershed is often home to endangered salmon and steelhead, protected under federal law. According to an article in Outside magazine, looking at the threat of marijuana farms to fish, “The Department of Fish and Wildlife is spending $12 million annually on fish-habitat restoration in Northern California, and that money is disappearing as quickly as the state’s water. But if these creeks dry up for three or four years in a row, it will all be for nothing. There will be no generations of fish to return; the runs will be dead.”

So how much of the water issues can be attributed to marijuana? It’s hard to know exactly, simply because of the nature of the industry. But if officials are right, it’s easy to start pointing fingers.

“It’s impossible to know exactly how much water is being drawn from streams for marijuana farms because, by its very nature, the industry is unregulated. Estimates for how much a plant consumes in a day vary from three to six gallons, depending on size, how they’re grown, and whether you ask Fish and Wildlife or a grower. But with farms increasing at unprecedented rates in past years, many residents believe marijuana is the biggest factor threatening Humboldt’s watersheds,” Erik Neumann wrote in his Outside magazine article.

One biologist found a way to get a pretty precise estimate, though, by combining Google mapping technology and satellite data to find marijuana farms paired with government data on stream flows. Scott Bauer, a wildlife biologist, estimates that around 30,000 marijuana plants are being grown in each river system, and that each of those plants uses about six gallons of water per day during marijuana’s 150 day growing season. As Bauer told the AP, ”We didn’t know they could consume all the water in a stream.”

Some marijuana farmers are working to clean things up, but the situation has been referred to as a “full-scale environmental disaster” by one Fish and Wildlife official.

The argument on the other side is that pot farmers are being unfairly blamed for environmental damage that can also be attributed to things like the timber industry and overfishing. As water in California becomes a hotter and hotter issue, you can be sure that the dispute over marijuana and its effects on the environment will continue.

Photo Credit: Mark


Jim Ven
Jim Ven6 months ago

thanks for the article.

Jonathan Y.
Jonathan Y.2 years ago

All California crops are jostling for water. Marijuana is indeed one of our state's biggest cash crops, but I don't think it consumes what strawberries or tomatoes do. For one thing, being illegal under Federal law means outdoor growing is limited compared to legal crops like rice which takes enormous amounts of water. For another, marijuana actually does better under a dry regime after the seedling stage. A day of deep watering and then a week of drying cause it to produce more resin and hence thc. That given, both local farmers and forest service reps. do have the right to complain about water which is simply taken from public or private land, without permitting or permission of the stakeholders.

Janice Thompson
Janice Thompson2 years ago


Nikolas K.
Nikolas K.2 years ago

Oh this so called expert claiming these plants consume all the water in rivers is stretching the fiction just a little too far for those of us who can think what is reality. One advantage of these plants is the fact they need very little water. its the GM modified plants that need more water so they wont drown in herbicide.

Nikolas K.
Nikolas K.2 years ago

This smacks of a fear mongering article by an anti marijuana crusader as the facts are baseless without substance even using a worthless quote of a comment alluded to a nameless fish and wildlife official. lets have members contact this department and see if such a view is held and why. I would be more concerned with the proliferation of GM foods than this healthy life giving plant. Oh, if Californians are really worried about the drought just contact your Congress member and get him to order that the military industrial alliance turn of the HAARP machine creating the Californian drought as all weather globally is affected by this machine depending on the political advantage to this alliance.

Robert Hamm
Robert Hamm2 years ago

You are right Jamie of course the paper industry doesnt agree and they have very rich lobbyists LOLOL

Roxana Saez
Roxana Saez2 years ago


Jamie Clemons
Jamie Clemons2 years ago

Hemp farming would have an extremely good benefit for the environment as opposed to traditional methods of making paper and cloth.

Mass V.
Mass V.2 years ago

this is all crap cannabis adds to soil its a rotation crop for all fields Fact is a nature insect repellant even so it kills bad insects cannabis is god sent so wake up and put the real devils like the DEA and make them DEAD

Janis K.
Janis K.2 years ago

If we could all grow our own plants (and for friends and family who can't) there would be less problem, and we'd save money.