Members of California’s Legislative Delta Caucus, including its co-chairmen, Sen. Bill Dodd, D-Napa, and Assemblymember Jim Frazier, D-Discovery Bay, sent a letter Friday to the Environmental Protection Agency objecting to a $1.6 billion loan for construction of the state’s controversial twin tunnels project on the Sacramento-San Joaquin Delta known as WaterFix. “This project poses devastating environmental consequences for the state’s most important waterway while threatening the economic vitality of the entire region,” said Dodd, one of nine lawmakers to sign the letter.