Scientists researching the potential effects of climate change have bad news for California wine producers and other agricultural interests. Future droughts are likely to be worse and last longer than the current dry spell gripping the state, and ameliorating those droughts will be more difficult than ever.

The research findings prepared by some of California’s top climate experts at the Scripps Institute of Oceanography and the U.S. Geological Survey suggest than by 2050 the state’s mountain snowpack, which provides the bulk of California’s fresh water, will be substantially less than at present. By 2100 it’s expected to be even worse, with the potential of making severe drought a year-round occurrence.

To cope with that possibility, the state Department of Water Resources has produced (and just released) a revised edition of its California Water Plan with an emphasis on managing the effects of climate change on the state’s water supply.

Among the plan’s 350 proposals to do that, according to the Sacramento Bee, are to breach levees and change land uses to allow rivers to reconnect with their historic floodplains, which would make it possible to hold floodwaters and renew groundwater wells. Other proposal involve changing reservoir rules to allow them to hold more water, plus increase conservation measures and water recycling.

The bill for all this won’t be cheap, the plan estimates. Some $200 billion will be necessary over the next 10 years just to maintain the same level of service, while in the future another $500 billion will be required from local, state and federal sources to make needed improvements.