Mike Patterson steered a motorboat across Hetch Hetchy Reservoir, about 300 feet above a valley floor that was hallowed ground to John Muir.
Patterson is a watershed keeper supervisor, charged with protecting this Tuolumne River supply for San Francisco and nearby cities.
But on this voyage, he was not taking water samples or looking for illegal shoreline campsites. He and other San Francisco employees were showing The Bee how the supply might be enhanced with water bought from the Modesto Irrigation District.
The proposed sales, the first of which could go to an MID board vote June 26, have spawned fierce opposition from people who fear they would leave farmers and Modesto residents short in dry years.
Supporters say the vast majority of the water would be freed up by conservation projects on the MID canal system funded by the sales. San Francisco has room for the extra water in the pipelines that run from the Sierra Nevada to the Bay Area.
"That's the beauty of a transfer with Modesto," said Steven Ritchie, assistant manager for the water enterprise at the San Francisco Public Utilities Commission. "We don't have to build anything to take the water."
He talked about the sales on a mid-May morning as the boat made its way across the reservoir, a few miles inside Yosemite National Park.
Yes, there's a big fake lake in a place that's supposed to be wild. San Francisco put it there in the early 1920s, after a long battle with Muir and other leaders of the early conservation movement.
"Nothing dollarable is safe, however guarded," Muir wrote in 1908. "Thus the Yosemite park, the beauty glory of California and the nation, nature's own mountain wonderland, has been attacked by spoilers ever since it was established, and this strife I suppose must go on as part of the eternal battle between right and wrong."
City officials defend the reservoir to this day, and they say it would work even better with the MID water.
Ritchie said this is the best option even with the price a proposed $700 per acre-foot to start. San Francisco wants to boost water conservation and recycling in the Bay Area, but even if successful, that would leave a gap, he said. Another option, a desalinization plant, is prohibitively expensive.
The MID transfer has another advantage San Francisco would divert the water at Hetch Hetchy, which is an especially clean source because the watershed is mostly wilderness, some of it bare granite. This means the treatment cost would be much less compared with water that comes from lower elevations, where sediment can be greater.
"Water quality here is really pristine," Ritchie said. "We're one of five cities in the country that don't have to filter their water."
The system does have a plant near the Bay Area that disinfects the water. Yosemite, as gorgeous as it is, has pathogens in its streams that can make you sick.
The Hetch Hetchy system, built in part to avoid a repeat of the 1906 fire that leveled much of San Francisco, has helped to make the Bay Area one of the most prosperous regions on Earth.
The service area includes much of Silicon Valley, where high-quality water is essential to high-tech manufacturing. The system also produces cheap hydropower for San Francisco's streetcars, airport and other municipal functions, and for sale to the MID and other wholesale customers.
Pleas to scrap the idea
Enough is enough, say people opposed to MID water sales that would provide San Francisco even more of the Tuolumne supply. With rhetoric that at times matches Muir's, they have pleaded with the MID board of directors to drop the idea.
"Why should we become a slave to San Francisco just to get the money to take care of some bills?" Modesto resident Clarence Blom said Tuesday during an emotional MID board meeting.
Linda Hodges said she and other Modestans already deal with year-round watering restrictions.
"You cannot guarantee that we will have enough water to meet our own needs," she told the board May 8. "How dare you promise our water to anyone."
The city of Modesto contends that it has priority over any outside buyer under its agreement with the MID for treated river water.
Critics urge the MID to reject the $700-per-acre-foot offer from San Francisco, which is about 70 times what farmers are paying this year. They say that if the district has water to sell, it should go to parts of the San Joaquin Valley where irrigation water is scarce.
Opponents also worry that the district, despite its apparently strong rights to the Tuolumne, could lose much of the water to downstream fishery releases if it gives the impression it has some to spare.
Supporters of the sales say the income could pay for an estimated $115 million in upgrades to the MID system. This work would include small reservoirs to catch water that runs out of the ends of canals into the Tuolumne, Stanislaus and San Joaquin rivers. This would free water upstream for San Francisco.
The income also could cover the estimated $25 million cost to the MID of a new federal license for Don Pedro Reservoir.
Some farmers skeptical of the San Francisco proposal have said they could accept an increase in their water rates to pay for at least some of the system upgrades. MID leaders said they will consider this.
Staying in the background
San Francisco officials, no strangers to controversy over water, are staying in the background as the latest debate plays out in and near Modesto.
But they were willing to let The Bee see how their system functions, including the boat ride, something not allowed for the public under the strict rules for protecting water quality.
Rare is the reservoir that has waterfalls flowing into it. Unlike their counterparts in Yosemite Valley, where the cascades thrill the crowds as they spill to the valley floor, these falls peter upon hitting the flat water.
But even a river changed by mankind can impress. The discharge from the dam water bound for the MID and downstream rivers sometimes creates a rainbow when the flows are right.
"I think this is something special," Patterson said while watching one such spectacle. "Any time we spill like that, it's an added bonus."
Bee staff writer John Holland can be reached at firstname.lastname@example.org or (209) 578-2385.