The drought means less fresh water and that is causing a salinity problem for California's canals.

Usually that fresh water keeps the salt water from moving too far up the Delta but because we have been so dry this year, that salt water is threatening some of the state's fresh water storage. 

Nancy Vogel with the California Department of Water Resources says to control this, the agency wants to build rock barriers in three Delta canals. 

Some farmers who pull water from those canals have expressed concern that this might affect water quality, but Vogel says there are measures the agency would put in place to make sure the water stays fresh.