Total damage estimates attributed to the March 22 megastorm, including Hetch Hetchy infrastructure, Tuolumne County infrastructure, and Caltrans roads in Tuolumne and Mariposa counties, now exceed $74 million, nearly double preliminary estimates.

That includes $3.2 million in damage to the state fish hatchery at Moccasin Creek, which lies downstream from the compromised Hetch Hetchy Water & Power’s Mocassin Dam.

The hatchery was flooded March 22 by waters that overwhelmed Hetch Hetchy’s storm-swollen Moccasin Reservoir and seeping Moccasin Dam.

Moccasin Creek Hatchery is a key facility for the state Department of Fish and Wildlife. Before the storm hit, the state relied on Moccasin Creek Hatchery to supply trout to multiple Central Valley and western Sierra Nevada reservoirs and other bodies of water.

State Fish and Wildlife people expect the hatchery to be operational sometime this fall, a spokesperson said Monday. It might take as long as 18 months to two years to restore and return the hatchery to full production, which includes breeding trout, hatching eggs, and raising fish to catchable size.

That same storm also tore up state highways 49 and 132 and multiple county roads that are still being repaired. Rainfall in Groveland and at Priest Reservoir exceeded 4.8 inches that day, according to Western Regional Climate Center data. Hetch Hetchy workers at Priest Reservoir measured 3.1 inches in a four-hour period from 11 a.m. to 3 p.m. Two deaths occurred in Mariposa County during the height of the storm.

Damage estimates increasing

Initial total damage estimates from the county and Hetch Hetchy in late March approached $50 million, with $40 million in damaged infrastructure at Hetch Hetchy’s Moccasin dam and reservoir.

Tuolumne County, Caltrans, state Fish and Wildlife and Hetch Hetchy damage estimates totaled $74.4 million as of Monday afternoon.

• Damage estimates for Hetch Hetchy infrastructure at Moccasin have now increased to approximately $43 million, Betsy Lauppe Rhode, a regional communications manager for the Hetch Hetchy Regional Water System, said Monday.

• Damage estimates to Tuolumne County roads and other infrastructure have increased to $8 million, Tracie Riggs, assistant county administrator, said Monday.

• Caltrans damage estimates to roads in Tuolumne and Mariposa counties from the March megastorm now total $20.2 million, Warren Alford with Caltrans District 10 said Monday. The state Department of Transportation now has director’s orders that include $5 million in damage to Highway 49 in Tuolumne County, $8.9 million to Highway 49 near Bagby on the Merced River, and $6 million to Highway 132 between Coulterville and the community of Don Pedro. The remaining money is for other storm-related damage, primarily on Highway 140 in Mariposa County.

More than a million dead fish

According to Peter Tira, a public information officer with state Fish and Wildlife, when the megastorm and its massive runoff hit Priest Grade and Moccasin, the state fish hatchery was holding about 1.6 million fish.

Most of them were rainbow trout, along with some brook, brown and golden trout. They were in stages of development from just-hatched eggs to fish weighing 1 to 2 pounds.

Tira said in late March more than a million fish died. More than a month after the March 22 storm event, Tira said the hatchery “suffered extensive damage estimated at $3.2 million.”

In response to questions Monday from The Union Democrat, Tira said the storm was so severe that massive flooding in Moccasin Creek “resulted in mud and debris laden floodwaters that fully engulfed the exterior raceways where the hatchery’s trout were being raised.”

Mud and debris also clogged the hatchery’s water intake in Moccasin Creek Reservoir, preventing water from coming into the hatchery, Tira said.

“The combination of mud, debris and floodwaters resulted in all of the fish being lost in the hatchery building, where eggs are hatched and baby fish are raised, and in the loss of most of the larger sized fish being reared in the external raceways,” Tira said.

Fencing at the hatchery was lost, as well as protective netting that surrounds outdoor raceways to keep birds and other animals from preying on fish, Tira said.

The state had 10 workers at Moccasin Creek Hatchery before the storm, and they all are still working there. State worker housing suffered “relatively little damage,” Tira said. There are eight residences on site at the hatchery.

There have been no staffing changes at Moccasin Creek Hatchery since the storm. Other hatcheries around the state are helping with fish production to offset losses at Moccasin Creek. Tira said Moccasin Creek Hatchery staff are receiving “lots of support” from other Fish and Wildlife personnel.

For people who fish and keep up with California Department of Fish and Wildlife timetables, Tira said Central Valley anglers anticipating the state’s general trout opener this Saturday can expect to find “many local fishing opportunities” despite the flood damage at the Moccasin Creek Hatchery.

Opening dates

Trout fishing on Moccasin Creek opens on Saturday, which is opening day of the general trout fishing season in California, Tira said. The creek flows to Don Pedro Reservoir and it is not fenced.

A big reason people have reported decent to great fishing at Don Pedro Reservoir since the storm is state Fish and Wildlife workers did an emergency plant of 150,000 rainbow and brook trout late last month at Don Pedro downstream from Moccasin Creek Hatchery.

Tira said the state Department of Fish and Wildlife was granted a small window of time to return to evacuated hatchery fish and rescue fish from the storm’s aftermath.

Alford with Caltrans District 10 said Monday that Highway 49 from Moccasin to Coulterville could be open by Memorial Day weekend or earlier if possible. Memorial Day this year is May 28. Opening of Highway 132 between Coulterville and Don Pedro is also expected by Memorial Day weekend.

Work on Highway 49 from Coulterville to Bear Valley is not going as quickly as planned and the hope now is to have it open by early July, Alford said. All prospective opening estimates are subject to change due to traffic incidents, weather, availability of equipment or materials and other construction-related issues.

Repairs to Hetch Hetchy infrastructure could be complete by sometime this fall, Rhodes with Hetch Hetchy said Monday.

Rhodes added that Hetch Hetchy leaders and employees are working with the California Department of Fish and Wildlife on repairs and reopening of the hatchery.

The Hetch Hetchy Regional Water System serves about 2.7 million residential, commercial and industrial customers in the Bay Area, including all of San Francisco and San Mateo counties and portions of Alameda and Santa Clara counties.

Contact Guy McCarthy at or 588-4585. Follow him on Twitter at @GuyMcCarthy.