“Rain, Rain, go away. Come again some other day” The words from this childhood rhyme are not the words that go through a water manager’s mind when the winter rains come. Winter rains bring the replenishment of supplies that will be needed to meet both irrigation and drinking water demands next summer in California. Without winter rains there will not be enough water when it turns hot and dry. So, what does go through a water manager’s mind when it rains, or more so, when it doesn’t rain?
Well, during winter rainy days, water managers tend to have smiles on their faces. Rainy days are good days, days that fill lakes and recharge groundwater basins. Thoughts on rainy days are of a coming summer with adequate water supplies and low stress levels because there is enough water for everyone.
Then there are those dreaded dry winters. Water managers tend to worry during long winter dry spells. They worry about how they are going to ration what little water that might be available to their district or region next summer. They spend time looking at various weather forecasts trying to mentally bring those desperately needed rain clouds to the watershed that feeds their water supply. And when some rain does come, every drop is cherished even though not enough of those rain drops fall from the sky. Then, after that short spurt of a rain shower, water managers check and recheck lake levels and figure out if there is enough water to make it through the summer. And if there is just enough for this summer, they then start thinking about how little water might be left in storage for next year (also known as “carryover” storage). While some reservoirs have more than one year’s storage, most have just one year’s worth of supply when completely full. This makes those winter rains all the more important.
Walter Cotter
General Manager
Browns Valley Irrigation District