The End of Cheap Water

Major water price increases and supply cuts are underway in southern California, both of which are long overdue. This part of the state is a desert, and yet too many people live there, and too many of them live their water consumption lives like they are somewhere with higher and much more predictable rainfall.

The end is here, or at least near. As one California water official put it today, “The era of cheap water is over”. Call it peak water, if you like, but the water calculus of California with respect to housing and economic development, long disconnected from reality, is finally on its way back to somewhere appropriate — if mostly because there is no choice.

There are two things underlying the new urgency. First, water supplies are declining because of a serially lower-than-normal (a dubious notion, but I digress) Sierra snowpack, which is the source of much California water. Second, and this is related, the Colorado river flows have been lower than normal (see above) for at least five years now.

The whole idea of “normal” is, in this context, nearly useless. With respect to Sierra snowpack, we don’t know what normal is, because we don’t have enough data, and, more importantly, whatever normal was, we are headed in a lower direction. At the same time, and as the following figure shows, we have now reconstructed Colorado River flows back to 1500 (via tree ring data), and it demonstrates that long periods of drought and reduced flows have been a regular phenomenon. Notice, in particular, that the period during which the Colorado River compact put together was abnormal in the first place, so the state straws — Arizona, Utah, Colorado, and California — sucking from the river are simply too big.