A new bill introduced by state Sen. Bill Dodd would expand the state’s ability to measure water flow in thousands of local streams in an effort to protect the state’s water supply. California currently collects data on hundreds of waterways through the use of stream gauges, which record the amount of water flowing in a river or stream. However, more than 3,200 local waterways, accounting for 70 percent of the state’s streams, have never been measured with a stream gauge. Another 15 percent do not currently have active gauges, according to Dodd’s bill.