ALBUQUERQUE — The gates on a concrete channel opened in December, signaling a new chapter in the history of the ancient Rio Grande and in the future of Albuquerque's water supply.

Narrow steel panels stretched across the river in the North Valley began diverting millions of gallons of water through an intricate, $385 million engineering marvel of channels, filters, pumps, pipes and sensors, mixing the river water with groundwater and sending it through the taps of more than a half-million Albuquerque and Bernalillo County customers. The clear water flowing from faucets looks nothing like the brown, dirt-laden water flowing into the system from the river.

More than ever now, the river is vital to the people living west of the Sandias. By 2011, half their water will come from the Rio Grande. Fifty miles upstream, Santa Fe is building another Rio Grande diversion project to serve its customers. Downstream, El Paso pulls the silt-filled water from the same river for household and industrial use.

Standing on the concrete walkway across the diversion intake on a freezing, windy March morning, John Stomp, water resources project manager for the Albuquerque-Bernalillo County Water Authority, huddled in a black wool coat and rattled off fact after fact about the project.

It took two winters to build the river diversion; the Colorado contractor could only build in the winter because of ecological concerns for the river's endangered native, the Rio Grande silvery minnow.

The 10- to 40-foot-wide panels can be opened in different sections, allowing Rio Grande water through at different points to avoid scouring a channel in the riverbed. Minnows can swim through, too, although many detour through a half-moon-shaped channel built just for them, where the water moves more slowly and rocks provide hiding places. The Bureau of Reclamation electroshocked the channel a couple of years ago to count the fish, and about 8,000 minnows floated to the top.

"The fish love this channel," said Stomp, 45.

So do a variety of migrating birds that stalk the channel for easy meals when the flow is low.

Water project converge

Thirty thousand tons of steel and 90,000 cubic yards of concrete went into the diversion project. Eight miles of 72-inch-diameter pipe delivers the raw river water to a group of desert-colored, Pueblo-style buildings, where it is cleaned up and delivered through another 38 miles of pipes to reservoirs around Albuquerque.

The water authority can take up to 90 million gallons a day from the Rio Grande under its permit from the state engineer. Half is native Rio Grande water. The other half is water imported to the river through another engineering marvel — the San Juan-Chama project that delivers San Juan River water through a tunnel under the Continental Divide to the Rio Grande via the Chama River.

The Albuquerque-Bernalillo County diversion project now takes only a fourth of the water that it could take, as it slowly tests the new treatment plant and delivery system. By 2011, it will take the full allotment, Stomp said.

Rio Grande water is used to carry the San Juan-Chama water through city pipes and must be returned to the Rio Grande at the other end as treated wastewater.

At the end of the concrete diversion passage is a contraption shaped like vertical blinds. These, and a controlled flow, allow fish that end up in the channel to pass safely without getting crushed against a screen.

The fish passage and the screens were among the diversion project's design features that made environmental groups happier with the massive project. Twelve groups protested initially when the diversion project design was released. The water authority settled with 11, including WildEarth Guardians of Santa Fe. But one coalition, which includes among its members a Los Lunas dairy farmer and a longtime river guide from Pilar, have protested the project all the way to the state Court of Appeals.

Stomp shrugged when asked why the group continues to fight the project. Different reasons, he said. In part, they worry about the impact on downstream water rights. Though he thinks the fear is misplaced, "if I were a farmer, I might have the same fear," he said.

An aquifer in decline

Stomp was born in Albuquerque about the time the San Juan-Chama Project was signed into law by Congress. As a kid, he spent more time in the Sandia Mountains, only a couple of miles from his home, than he did down at the Rio Grande. But he recalled his mother taking him on walks through the river's bosque.

He set out to become an architect and discovered he had little talent for drawing. Instead, with his math skills and his love of problem-solving, he earned bachelor's and master's degrees in civil engineering at The University of New Mexico. His master's thesis was on the ability of wetlands to remove heavy metals from wastewater.

He and his wife moved briefly to Los Angeles until an earthquake made them decide they were homesick.

Stomp's hometown, meanwhile, had found out in the early 1990s that the gigantic aquifer once thought capable of sustaining the city for decades was declining. "Problem was the aquifer was getting depleted because it wasn't directly connected to the river," he said.

Plus, the rapidly growing city was pumping out the water faster than it could be recharged from the nearby Sandia Mountains. Over time, as the water levels dropped, the land began to sag and subside, like a floor with the support beams pulled out.

Albuquerque and Bernalillo County joined forces to devise a long-range plan for saving the groundwater by using renewable surface water from the river. When Stomp took over as project manager in 1997, the idea was inscribed in five paragraphs. It took five years, hundreds of public meetings, dozens of proposals, a lengthy environmental impact analysis and reams of paper before the final project was approved.

Stomp said hundreds of public meetings were held up and down the Rio Grande — from Socorro to Española and all around Albuquerque. Seven water-rate increases were required to pay for the project. "It was a 30 percent increase over the seven years," he said.

Construction on the water diversion project began in 2004 and was completed last year.

A display of engineering prowess

Stomp's given a lot of tours of the project since it was finished. He doesn't seem to tire of showing off the results of so much engineering prowess. "I love this work," he said as he drove around a couple of holding ponds the size of football fields.

Razor wire surrounds the metal fence around the property. Motion sensors and cameras watch for intruders. "Bioterrorism is real, but with this much water, it would take a lot of chemicals to do it," Stomp said.

The bigger concern is the family of ducks that took up residence in the holding ponds. "It's not what we want to see, but how are we going to stop them?" Stomp said.

The raw river water dumps into these ponds first. They hold 100 million gallons, enough to serve the city for one day. The water is kept there for 24 hours, allowing gravity to pull the heaviest dirt particles to the bottom.

The slightly clearer water is pumped to the first of several buildings on 160 acres the water authority owns for the water-treatment plant. Computer-monitored cyber keys ensure only authorized personnel enter each one. Stomp is one of the few whose key works at all the buildings.

"We use gravity to get the dirt out," Stomp said as he led the way into the first building. "When gravity doesn't work, we add ferric-chloride, a coagulant, to the water. The chemicals plus microsand make the remaining particles bigger so gravity can work."

It takes two more buildings filled with noisy pumps, gigantic blue pipes and some mixing tanks to coax out most of the finer particles.

Water cleanliness is tallied by sending a light through a sample and measuring how much is blocked by sediment and other particles — known as turbidity. Albuquerque is aiming for turbidity levels of less than half that allowed by federal standards.

The sediment removed at the water-treatment plant is mixed with sludge from the city's sewage treatment plant and with wood chips to make composted fertilizer.

Ensuring quality drinking water

The largely sediment-free water is next ozonated twice to break down organic materials including pharmaceutical residues. Then it is sent through activated carbon filters to remove any remaining particles, and finally chlorinated.

Ozone is made on site and contained there — none is released into the atmosphere — and it is an expensive process, Stomp said. "Ozone breaks cell walls much better than chlorine. The problem with ozone is it doesn't last. It goes into the atmosphere very rapidly," Stomp said.

Chlorine has a long life and is added before the water is finally shipped through pipelines to homes and businesses in case contaminants enter the water at line leaks along the way or at the end spot.

Santa Fe's water-treatment plant for the Buckman Direct Diversion project currently under construction will be similar, except it will go one step further and include a microfilter.

Albuquerque and Santa Fe pay close attention to the quality of the water that finally makes it to people's taps because both cities have relied until now on clean groundwater, Stomp said. In addition, Santa Fe gets water out of reservoirs fed by snowmelt and mountain streams. "Everybody is accustomed to such clean water that you have to match the quality of that water, otherwise people would notice the difference," Stomp said.

The Albuquerque-Bernalillo County Water Authority is researching the possibility of injecting cleaned river water underground to beef up the aquifer at times when demand is lower. Any injected water must be chemically compatible with the existing groundwater.

Focus on green power, conservation

Powering the water diversion project isn't cheap. The electricity budget before the drinking water project was about $5 million a year to extract groundwater and pump it through water lines. "Now it's about $8 million a year," Stomp said.

The water authority is looking at adding solar panels or some other renewable-energy system to produce some of its own electricity; already the city's wastewater-treatment plant produces most of its own power using methane gas off the city's sewage.

When fully online, the water diversion will provide all of Albuquerque's drinking water in the winter. From spring through fall, when demand is higher, river water will be mixed with the water pumped from municipal wells.

The water authority hired 20 more people to keep the intricate system running smoothly; it is staffed 24 hours a day.

Stomp said he's been asked a lot what would happen if a long-term, severe drought — the kind that's been part of New Mexico's distant past and could be worse in the future with climate change — dried up the rivers.

"I don't see a scenario where there's never going to be San Juan-Chama water for some very long period of time. I don't believe that we're going to have no snow in the San Juans for 20 consecutive years," Stomp said. "But if it did happen and there wasn't any water in the river, then we would obviously shut this project down and go to our wells. That's why it's so important to make sure there is a drought reserve in the aquifer."

To that end, the water authority promotes water conservation. The goal right now is to reduce customer usage from 161 gallons per person per day to 150 gallons, but Stomp said they'll keep working to push it lower. The city uses reclaimed wastewater for parks and landscaping. Water restrictions could get tougher under a severe drought scenario.

"We may reach a time where we have to consider a scenario where we clean up all our wastewater to drinking water standards and re-inject it," Stomp said. "Right now Cloudcroft is doing that."

He's not convinced brackish water pulled from thousands of feet underground is a good supply. "It is hugely expensive to treat and there are environmental concerns over what to do with the brine, and then it's not a sustainable supply. It may be good for filling little gaps in supply," he said.

Stomp said the water authority is developing a water budget and a dynamic model to look at what happens if climate change fears are right and a severe, longtime drought occurs or water demand changes.

He thinks one of the things missing in water planning is how to better manage in a good water year. "Right now, get a wet year and everyone breathes a sigh of relief and stops worrying about managing the river," he said. "We need to use wet periods to recharge the aquifer, figure out how to capture more of the water. We do a lot of planning for drought. But we don't do much planning for wet years."

Contact Staci Matlock at 986-3055 or smatlock@sfnewmexican.com.

Editor's note: Rio Grande Voices is an occasional series about people whose lives or careers are tied to the river.