We sounded the “May Day” alarm on May Day for the water supply in California this year. How are things looking a month later? In a word, bleak. The percentage of water that the partners in the State Water Project will receive — the “Allocation” — stands at a very low 35 percent. That’s not the lowest we’ve seen, but it is the lowest in the past several years.
To get a sense of the situation we have two graphics today from the Department of Water Resources. In the first, we see the storage status of all the major reservoirs in the State:
The current levels are less than the historical averages for this date, but not significantly so. However, if you compare these percentages to those of one month ago, you see each of them down by 10 – 20 percent!
Of MOST concern is the paltry amount in storage in the major reservoir south of the Sacramento River Delta, San Luis Reservoir. Due to environmental restrictions on pumping during the only period of significant flood flow in the system this year, San Luis is critically low. Essentially all the water in San Luis is pumped in from the Delta, and that can only happen when there is a significant inflow to the Delta. Under normal weather conditions for the rest of the year, this might mean no significant pumping into San Luis until late Fall. This means that we might consider ourselves fortunate if the allocation stays as high as 35 percent!
The other graphic today shows the storage in the largest component of the SWP, Lake Oroville:
Note that the storage level is relatively high in contrast to the other four years depicted on the graph. What is disturbing is the downward trend. In none of the other years do we see a drop in storage in May! We consider this to be MOST dis-Maying!
There is your water supply update, and “bleak” is the word!