Q: Why are we considered to be in a drought, at least in the Sierra foothills, when our rainfall totals are at nearly 50 percent of “normal” for the precipitation year? – Phil Zink, Colfax, CA
A: The state Department of Water Resources doesn’t list a series of thresholds that, once crossed, mean we are in a drought. Instead, state officials consider drought a gradual phenomenon that affects different people in different locations in different ways.
When Gov. Jerry Brown declared the state to be in a drought earlier this year, he noted that, “California’s largest water reservoirs have very low water levels for this time of year; California’s major river systems ... have significantly reduced surface water flow and groundwater levels throughout the state have dropped significantly.”
If drought is simply several consecutive years without much rain or snow, then the current predicament qualifies. Snowpack in the Central Sierra is at 32 percent of normal, roughly where it was at this time of year in 1977, the driest water year on record.
Last year at this time, the Central Siera snowpack was at 56 percent of normal; in 2012, it was at 44 percent.