With water capacity less than 45 percent, boats are banned
Published in the Sept. 2-15, 2015 issue of Morgan Hill Life
By Staff Report
Anderson Lake County Park east of Morgan Hill was closed last month to recreational boaters due to the water level reaching a point too low for safe launching of vessels.
Santa Clara County Parks and Recreation made the decision to close for boating use the county’s largest reservoir effective Monday Aug. 17. The threshold capacity for boating is 45 percent or more (about 40,000 acre feet) and the water level reached a 44.3 percent capacity last month.
“I understand it’s really about the boat launching ramp,” said Marty Grimes, a spokesperson for the Santa Clara Valley Water District which manages the reservoirs in the county. “The ramp only goes down to a certain level. So once the water gets below a certain level, it’s not safe to launch boats down there.”
One of the reasons for the lower water level was due to a malfunctioning water pipe near Casa de Fruta on Pacheco Pass, causing the water district to switch to Anderson Lake for water to feed treatment plants in the northern part of Santa Clara County for safe use for drinking, bathing and other uses by county residents and municipalities. This increased the Anderson Lake water removal to 3 percent, compared with the normal 1 percent for treatment use.
“We were using San Luis Reservoir water which is imported water that comes to us from the Delta through the Central Valley Project water,” Grimes said. “When that pipe went down, we needed to switch the sources to Anderson to feed two of our water treatment plants, and as a result, more water was taken from Anderson at a higher rate, so that has caused the water level to go down.”
The water level did not go down because of the dam retrofitting project scheduled for 2017, he emphasized. Because of the potential of dam damage from a major earthquake in the region, the water district needs to keep the capacity of Anderson Lake at a maximum of 65 percent capacity until the dam can be strengthened. The four-year drought has also brought the water level down.
The original boat season started April 15 and was scheduled to go through Oct. 14 before the closure to boaters. It’s unlikely that the County Parks will re-open the lake to recreational boaters this season, Grimes said.
“We can’t make any commitments,” he said. “It’s possible that the water level at Anderson could go up, but it doesn’t seem likely that it would go up enough to allow boating this season.”
An El Nino winter season is expected for this winter, with heavy rain storms helping to raise the water level at Anderson Lake for next spring’s boating recreation season.
“We’re hoping for that,” Grimes said. “We’re not, obviously, banking on that, but it would be a welcome occurrence if we got a good rain year and, more critically, a heavy snow-pack in the Sierras. But we also don’t want to get too much rain all at once. The water district is a flood protection agency and we’re preparing for the possibility that it could be a strong winter storm season.”