Constructed in 1945 by the U.S. Coast Guard, this concrete building sits 25 feet behind the lighthouse. It held the backup generator for the lighthouse light and foghorn, and served as the watch room for the light keepers. The watch room was manned 24 hours a day with the light keeper and two crewmen each putting in an eight hour shift. In addition to maintaining the Browns Point light, the crew also watched over the lights at Point Defiance and Point Robinson.