Five months after California outlined a $383 million plan to slow the shrinking of the state’s largest lake, agencies will try to make sure officials honor the commitment, according to a report. The proposal announced in March involves building ponds at the north and south ends of the Salton Sea, a salty, desert lake that has suffered a string of environmental setbacks since the 1970s. The plan left agencies in the Imperial Valley unsatisfied because only $80.5 million has been approved so far — and they questioned whether the state would follow through and live up to its commitments during the next decade.