The DCPP waverider buoy, located about a 1/4 mile off the breakwater, was swapped out last Wednesday morning by company divers, a marine meteorologist and a marine biologist. Due to the limited battery life in the buoy, the device needs to be exchanged periodically in order to continue to provide accurate computerized swell information to the plant. The batteries in the buoy last about eight to nine months before they need to be replaced. "In preparation for the upcoming winter season, we needed to go ahead and swap out the waverider buoy so we will have a whole new set of fresh batteries installed," says John Lindsey, Diablo marine meteorologist. The batteries should last through April, 2001.
The purpose of the waverider buoy is to provide the plant with an early warning of a swell event that may be approaching the plant and the intake. The buoy has a telemetry system which broadcasts to the DCPP Ocean Lab swell readings 24 hours a day, seven days a week. These data are in turn downloaded to the Coastal Data Information Program (CDIP) at the Scripps Institution Of Oceangraphy, processed and disseminated to the National Weather Service in near real-time. With these warnings, the plant can take actions to mitigate the affects of the possibility of kelp entering the intake area after being sheared by a large swell. The plant has only one buoy deployed off our coastline, but the Ocean Lab is still able to relay swell information from more than 25 similar buoys along the Pacific seaboard, from the Gulf of Alaska to Christmas Island.
"The exchange of the two buoys went very well, with preparation the key to the short diver time in the water during the actual exchange," says Lindsey. For a while, the computer picked up two distinct readings from the two buoys as they bobbed together in the water. But as the older buoy was hoisted ashore and the antenna was disconnected, the measurements settled back down with a new and stronger reading coming across the computer screen.