California drought pits farmers vs. cities. But neither is the biggest water victim in California, the state’s fish.
The current water-shortage crisis in California — the worst in state history — is partly caused by what many predict will be a huge growth in the state’s population over the next few decades, which will increase demands on water. As a result, the amount of water Californians take out of the state’s rivers and streams during rainy periods grows more than any other source of water, and the amount of water taken out of the reservoirs at the end of rainstorms grows even more than that.
But even while the amount of water that California’s rivers and streams take out of them grows, demand for the state’s water is growing, too.
That water demand is likely to go up significantly in the coming decades.
In recent decades, the state has been able to grow water supply with relatively low rates of population growth. But with future population growth, the amount of water the state could grow without any additional water is much smaller than it was 20 years ago. The amount of water that could be produced without growth in demand is limited by the amount of water available at the end of drought periods.
That is why a lot of water-shortage observers have gone to war with the notion of growing demand for water as a cause of the drought. They want to find a way to grow water supply without having to increase demand.
This is the central reason why the state could have water during drought times but not during dry periods — and why California should be able to grow supply, but not need it, without changing water demand.
But here’s where it gets tricky: The amount of water California could produce without more water demands is a lot less than some other sources of water. California has to produce more with higher growth in population than almost every other water supply in the world. What makes the situation more tricky, though, is that those other sources of water grow during drought periods.
Dry-season growth in population, for example, is greater than water demand growth by three to four times in California.
Other sources of water — lakes,