Introducing CIMIS – which is the California Irrigation Management Information System.
CIMIS plays a big, hidden role in our gardening lives – and in the future you will hear more about it. It is a statewide program in what is called the Office of Water Use Efficiency (OWUE). This “efficiency office” is part of California Department of Water Resources (DWR), which in turn is part of the Natural Resources Agency.
CIMIS manages a network of over 120 automated weather stations all over our state. It was originally organized by the water resources people and UC Davis to assist California’s big water users (agriculture) to manage their increasingly controlled and limited water resources.
The idea was to figure out how much rainfall a particular area received. The farmer, knowing how much water a particular species needed over a year-long period, would be able to calculate supplemental irrigation needed to keep the plant at optimal health without wasting water.
When we started to help homeowners reduce turf areas and plant with natives, this data was invaluable in making comparisons between native plant needs and the natural rainfall of an area. Match your plant to your rainfall and happiness ensues. It reminds me of the Dickens character, Mr. Micawber defining his life view, “Annual income twenty pounds, annual expenditure nineteen pounds nineteen and six, result happiness. Annual income twenty pounds, annual expenditure twenty pounds nought and six, result misery.”
So, annual CIMIS data rainfall twelve inches, annual irrigation need for Ceanothus eleven inches, results happiness. Annual CIMIS data rainfall twelve inches, annual irrigation need for Kentucky bluegrass thirty-six inches, result misery.