California cities and farms should brace for little or no water from the state’s big reservoirs in the coming year, a prospect that signals more water restrictions for households and more fallowed fields in the farm belt.

The warning was delivered Monday by state and federal water officials who said they are preparing for the possibility of a fourth year of drought. Both are considering, at least initially, reduced allocations for the many water agencies that contract for reservoir supplies from California’s sprawling water projects.