Proposed tunnel would move water out of Lake Nacimiento. Residents are fighting back

Saying they want to capture much-needed water that flows over Lake Nacimiento’s spillway, Monterey County officials are planning to build an underground tunnel that would move some of its water to Lake San Antonio farther north.

But that plan has upset residents near Lake Nacimiento, who fear that could hurt water levels — and recreation on the lake — as well as groundwater along the tunnel route.

“We have nothing to gain and everything to lose,” said landowner Bill Capps, who is one of about 50 people in the path of the proposed project.

He and a handful of other landowners have delayed the project by refusing to allow Monterey County engineers on their land to drill test holes, fearful that it could pollute their groundwater.

Monterey County officials say the $80 million project would help prevent flooding below Lake Nacimiento as well as provide additional storage in Lake San Antonio for water that would otherwise fall over the Nacimiento dam spillway. In addition to the 2.3-mile tunnel, the project would raise the San Antonio spillway by 10 feet, increasing the storage capacity of that reservoir by 59,000 acre feet, or nearly 18 percent.

While Lake Nacimiento is in San Luis Obispo County, Monterey County controls the water, and Salinas Valley would benefit the most from the extra storage.

Nacimiento fills three times faster than San Antonio because it is in a bigger watershed. Nacimiento has a capacity of 377,000 acre feet and was 44 percent full last week. Lake San Antonio’s full capacity is 335,000 acre feet and was 32 percent full.

“Last winter, we did flood control releases of 192,000 acre feet (from Nacimiento). If we had the tunnel, we would have been able to, during the same time period, transfer 88,000 acre feet to San Antonio,” said David Chardavoyne, general manager of Monterey County Water Resources Control Agency.

Instead of that water flowing to the ocean, water diverted by gravity through a 10-foot wide tunnel would primarily be used in Salinas Valley to percolate into the groundwater basin and irrigate agricultural fields, he said.

The project could be complete by 2021, depending on various factors, including if Monterey County residents who would benefit from the project approve a tax in 2019 to help pay for the tunnel’s construction, Chardavoyne said. The state allocated $10 million to the project last year.

Monterey County, however, has met resistance from San Luis Obispo County residents who feel they’re bearing the brunt of the impacts without any benefit.

“We don’t get any more water. We don’t get any more land. We don’t get anymore money,” Capps said.

Public meetings held on the issue have been described as tense and emotional, as landowners are fearful of losing easements of their property through eminent domain and lake enthusiasts worry the tunnel could drain the lake.

When water is low, people stop coming

How the project would impact Nacimiento lake levels, and by extension the local economy, is unknown. That information will depend on analysis that hasn’t been done yet, Chardavoyne said.

The reservoir is a popular recreation area when the water is high. When it’s low — as it was in the midst of the drought — lake fingers become dry canyons and boats are left sitting in mud.

“Consequently, people stop coming to the lake. They can’t recreate; they can’t fish. The lake becomes undesirable, and then people stop buying property. Gas stations, the grocery store, they depend on lake traffic,” Bing Smith said.

Smith, an attorney who owns a log cabin in one of the subdivisions around the reservoir, is also a member of Nacimiento Regional Water Management Advisory Committee that represents property owners, visitors and lake enthusiasts.

The lake is full at an elevation of 800 feet. NRWMAC wants to maintain a minimum lake level of 780 feet, and it has focused on the proposed depth of the tunnel as a key issue of contention.

As proposed, the tunnel intake would be located at 745 feet, and no water would be moved through the tunnel unless the lake is above 760 feet, Chardavoyne said.

“That doesn’t mean we’re going to take every drop of water above 760,” he said.

Still, he said, “The landowners who are going to be paying for this project want to make sure they’re getting value for what their paying for... I don’t think we can neglect the stakeholder interest of the people actually paying for it.”

Relations between Monterey County and lake residents are already strained as residents have said they’ve had to fight to maintain lake levels and management resources. Monterey County is responsible for operation and management for the lake, which it developed and paid for.

“Monterey County just does not care about people around Nacimiento,” Smith said.

“Just do right by us”

The interlake tunnel project was recently delayed by six months, in part, by a handful of landowners who denied county officials access to land to drill test bores for engineering planning purposes.

“We’re a little frustrated because we’re being blocked to be able to do the science to answer everybody’s questions,” Chardavoyne said.

Although landowners worry that they could lose easements across their property, their immediate focus is on protecting their water source.

“Mostly, I am concerned about my well. It affects my land, my houses and my livestock,” Capps said. “We’re being hard-nosed because it involves our land, our water.”

Pockets of oil and sulfur have been found underground in the area, and he’s concerned construction of the tunnel, or even drilling test bores, might disrupt or pollute his or his neighbors’ groundwater.

In response to those concerns, Monterey County adopted a resolution that says the Water Resources Agency is “committed to mitigating the potential impacts to private wells as a result of the construction and operation of the tunnel” and will take measures “to fully address impacts to wells that can be proven to result from construction.”

But that’s not enough, several landowners have said. As protection, they’ve asked Monterey County to indemnify their wells, to insure they’ll be reimbursed for any disruption to the flow of water.

To Capps, the matter is simple. “Just do right by us, that’s all we’re asking,” he said.

To Monterey County officials, the request is unnecessary. Chardavoyne said the county resolution means that “if there is an impact, that is verifiable, they will be made whole.”

Plus, he says, his geotechnical guys, “are shaking their heads and saying, ‘nothing’s going to happen.’ ”

“Any concern should be about easement areas and not the bore holes,” Chardavoyne said.

This story was originally published November 11, 2017 at 11:35 AM with the headline "Proposed tunnel would move water out of Lake Nacimiento. Residents are fighting back."