Caltrans got one step closer to its controversial $500 million project to widen Highway 37, a notoriously trafficky corridor, with an infusion of funding Thursday. But critics said the money could be wasted as rising tides are expected to flood the low–lying highway within decades. On Thursday, the California Transportation Commission approved $73 million toward the plan, which calls for widening Highway 37 between Sears Point in Sonoma and Mare Island in Vallejo from two lanes to four. Caltrans said the project will greatly reduce congestion on a highway used by 47,000 daily. However, the highway is also expected to be inundated by rising tides by 2050, threats that will not be addressed by the project, Caltrans said. Instead, the agency has a separate $10 billion plan to elevate and protect the highway in the future. … Portions of Highway 37 “will be completely inundated by 2050,” especially during major storms and king tides, and there will be increased flooding leading up to that time, Caltrans said in a statement.