last month deadly wildfires in California destroyed thousands of homes killed at least 29 people and will likely cost hundreds of billions of dollars President Trump has repeatedly claimed that state officials made this disaster worse by how they manage the state's complex water system William brangham looks at those allegations and the realities of water management in the nation's most populous state while fires were still burning in Southern California and Crews were trying to save lives and property then president-elect Trump took aim at California's Democratic governor Gavin Nome it's very sad because I've been trying to get Gavin Nome to allow water to come you'd have tremendous water up there they sent it out to the Pacific and after he took office he kept coming back to how California officials managed their water blaming them for making the fires worse we're demanding that they turn the valve back toward Los Angeles millions of gallons of water are waiting to be poured down fire that could have been put out if they let the water flow but is it true that more water from Northern California could have helped Los Angeles there's no truth to that Donald Trump has a strange fixation with California Water policy he has for many many years he comes out here he talks about some imaginary valve or some imaginary faucet that he or someone else could turn to increase the amount of water that flows from Northern California to Southern California it's sort of an odd fixation let's start with some context California has one of the largest and most complex Water Systems in the world it's responsible for delivering drinking water to almost 40 million people and irrigating Farms that grow 3/4 of the nation's fruits and nuts that enormous task is Complicated by an increasingly hot and dry climate growing demands for that water and geography so where does the state's water come from about a third of Southern California Supply comes from the Colorado River and then there's precipitation even though 75% of the state's rain and snow falls north of the state capital Sacramento 80% of the demand comes from areas further south in cities like San Francisco and Los Angeles and the vast farmlands of the sanwen valley when rain and snow fall in the north whatever doesn't evaporate can seep into the ground to be pumped or travel through massive networks of dams reservoirs canals and aqueducts across the state and how all that water is allotted and to whom has been a source of friction in California for decades presently it will be used by thousands of farmers who will transform the Arid desert into fields of green crops the disputes are who gets to use how much water for what purposes we fight between cities and farms and we fight over how much water belongs to the ecosystems but president Trump's accusations have driven been renewed attention to this issue during the blazes firefighters reported that hydrants had low pressure or ran completely dry despite the president's claims that water being held up north was to blame experts say Supply wasn't the issue in fact most key reservoirs serving Los Angeles County had more water than normal the problem was infrastructure our Urban water systems are designed to help us put out house fire or a couple of house fires they're not designed to deal with the massive kinds of wildfires that swept through the Los Angeles area you know if you have a glass of water and you have one straw you can drink that water and there's no real problem but when you have a thousand straws in that same glass of water though the glass gets drained immediately and no matter how fast you try to refill it you can't refill it and that's what happened here Trump also keeps coming back to something else that the fires were made worse by California's protection of an endangered fish known as the Delta smelt again analysts say there is no connection as far as we can tell there's no relationship between the fires in Southern California and leaving some water in the rivers for Delta smelt and other endangered fish the reservoirs in Southern California are full and there's not a limitation on water supply there even so on January 24th Trump signed an executive order to override State policies and maximize water water delivery days later the US Army Corps of Engineers which controls some water systems in the state released over 2 billion gallons of water from two dams in the San waen Valley the president posted this photo saying beautiful water flow that I just opened in California I only wish they'd listen to me six years ago there would have been no fire there's no ability physically to move the water in those reservoirs to the Los Angeles area there are mountains in between there's no Aqueduct no pipelines no systems of water transfer the loss of that water from those reservoirs some of it evaporated some of it may have gone back into groundwater but it certainly never reached Los Angeles the water that was dumped belonged to Farmers in Southern California and now will not be available to those farmers who are going to need that water in the hot dry season that's coming now we should note we spoke to a farmer in the region who said while it'd be better to have that water later in the year the release was relatively small and won't have a huge impact and in the long term many farmers would be supportive of the president's push to increase water flow there but again that had no bearing on the fires or the devastating toll they took on Southern California for the PBS NewsHour I'm William brangham