In an average winter, rainfall in Sonoma County peaks in January and begins to taper off in February. That history doesn't bode well for a quick end to the drought, which is now in its third year.
The magnitude of the crisis is becoming clearer with reports that the Sierra snowpack is 12 percent of normal, the state is halting all deliveries to water contractors, and the water supplies for 17 mostly rural communities, including Cloverdale and Healdsburg, could go dry in the next 60 to 120 days.
As a result, pleas for voluntary conservation are giving way in many places to stricter measures.
With no assurance that year three of the drought won't be followed by year four, it's prudent to start making mandatory cutbacks now.
For these measures to succeed, however, water purveyors must overcome public skepticism.
In Southern California, some water districts are worrying publicly about crying wolf. They want to wait and see if spring storms develop before asking customers for anything more than voluntary cutbacks.
Utility regulators, meanwhile, are assessing the impact on the supply and cost of hydro power.
Closer to home, some readers are telling us that they can't do much more after years of saving rinse water for plants, removing lawns and other conservation measures. Others complain that steep rate increases followed past conservation efforts.
Their concerns aren't unfounded.
Over the past 10 years, Sonoma County Water Agency deliveries declined about 20 percent, from 66,500 acre-feet to 54,200 acre-feet, while wholesale and retail water rates have continued climbing to meet the fixed costs of maintaining and operating the water-supply network.
So we were pleased to hear Water Agency officials pledging on Monday to tap reserves to avoid charging people more for using even less during the current drought.
"Proactive financing will help prepare for declining water sales due to the drought and resulting necessary conservation," said Grant Davis, the Water Agency's general manager.
By taking $6.6 million from reserves, agency officials say they can scale back this year's rate increase from as much as 13 percent — the amount suggested by dividing operating costs by water sales — to less than 4 percent.
It's not yet clear how that will translate to residential rates. The Water Agency is a wholesaler, setting rates for cities and water districts that serve residences and businesses in Sonoma and Marin counties. They will make their own decisions about passing on some or all of the Water Agency's rate increase.
They, too, should look for alternatives to raising rates while asking, or perhaps requiring, customers to use less water.
Despite Sunday's welcome rainfall, long-range forecasts and a century of weather data strongly suggest that the drought will last into spring and summer, the seasons when water use increases. We can't change that. We can conserve more, starting now.