Scientists Publish Groundbreaking Work on Marijuana’s Effect on the Environment

Marijuana Dry Stream Bed
Marijuana Dry Stream Bed
California Department Of Fish And Game
California Department Of Fish And Game

California –-( Environmental scientists with the California Department of Fish and Wildlife (CDFW) recently published a first-of-its-kind study that clearly shows that water used for growing marijuana has a devastating effect on fish in the state.

The study showed that during drought conditions, water demand for marijuana cultivation exceeded stream flow in three of four study watersheds.

The resulting paper, entitled “Impacts of Surface Water Diversions for Marijuana Cultivation on Aquatic Habitat in Four Northwestern California Watersheds,” concludes that diminished stream flow from this water-intensive activity is likely to have lethal to sub-lethal effects on state and federally listed salmon and steelhead trout and will cause further decline of sensitive amphibian species.

The study was published online in the scientific journal PLOS One and can be found here.

By using online tools to count marijuana plants and measure greenhouses, and conducting inspections of marijuana cultivation sites with state wildlife officers and local law enforcement, CDFW scientists quantified plant numbers and water use. Utilizing stream flow data provided by staff at the National Oceanic and Atmospheric Administration (NOAA), CDFW determined water demand for cultivation could use more than 100 percent of stream flow during the summer dry season in three of four study watersheds. Stream flow monitoring conducted by CDFW in the summer of 2014 appeared to verify these results.

“All the streams we monitored in watersheds with large scale marijuana cultivation went dry,” said CDFW Senior Environmental Scientist Scott Bauer, lead author of the research paper. “The only stream we monitored that didn’t go dry contained no observed marijuana cultivation.”

CDFW’s Law Enforcement Division works closely with dozens of other state and federal agencies to eradicate illegal marijuana grows on public, tribal and private lands as well as protect the state’s natural resources.

“This research paper demonstrates the importance of greater regulatory efforts by state agencies to prevent the extinction of imperiled fisheries resources,” said CDFW Assistant Chief Brian Naslund. “CDFW’s new Watershed Enforcement Team (WET) was created with just that in mind.”

The WET program works with agency partners to protect public trust resources from the negative effects of marijuana cultivation, which include both excessive water use and pollution.

CDFW will continue to monitor the effects of water diversion for marijuana cultivation on stream flow through the summer of 2015.

Marijuana cultivation is legal in California if growers have the proper CDFW lake and streambed alteration permits. Responsible growers help conserve the state’s natural resources and are less likely to be subject to enforcement action.

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It’s a flippin’ WEED, man. They DO NOT require copious amount of water. The only reason illegal grow ops affect water resources is that they tend to be in such remote areas to avoid detection, and those areas tend to have scarcity of water. And besides,…even if the article was absolutely 100% accurate,…THAT cost is still better than the cost we have been experiencing from the war on we the people via the current prohibition. Prohibition of all kinds is never successful and never worth it.


More shit brought to you at your expense from our government. Usual


“Our water demand estimates were based on calculations from the 2010 Humboldt County Outdoor Medical Cannabis Ordinance draft [27], which states that marijuana plants use an average of 22.7 liters per plant per day during the growing season, which typically extends from June-October (150 days).”

I call BS!
WTF? 22.7 liters of water per day, PER PLANT???? That would 5 US gallons per day. What plant uses 5 gal of water a day?
This is what happens when CDFW does an environmental study. Make the numbers match the expected political outcome.


Haha never been up to Mendo I take it? There’s a reason it’s called “trees” by some. 110 degrees on a 15 foot baby will definitely take this much water per day, if not more.

John Mark

If marijuana was allowed to be grown in other areas of the country such as the South which is primarily agricultural already and has adequate water supplies these issues could be avoided. You are focusing on what is considered a unpopular crop when drought conditions could be applied to any crops in these areas.


“…Environmental scientists…” The only 2 words you need to see to know this is pure horse pucky.

As said above – Hemp and the Marijuana dirivitive have been growing wild for millions of years and the planet survived – UNTIL the Government got involved.

Government has outlived its usefulness.


More idiocy… if you allowed pot to be grown in the same manner as regular crops (on a managed farm), this would not happen. just legalize it and turn it into a legit business… the “war on drugs” has been a dismal failure and it’s effects are now impacting the environment! At least legalize it for medicinal uses (and there are many legit)… how many times do you touch the burner before realizing it’s a bad idea? Well, politicians….



I agree with you, after Millions of Years of Natural Growth and other plants with similar effects. These Scientists are finding this out NOW…