TIJUANA — As they watch millions of gallons of treated Tijuana wastewater flow into the Pacific Ocean each day, Baja California authorities say they have a better idea: Why not pipe it to the Guadalupe Valley, Baja California’s winemaking region, where the water table has been falling even as the area has risen in international renown?
Gov. José Guadalupe Osuna Millán’s government is proposing a 46-mile aqueduct that would carry the treated water from eastern Tijuana to the vineyards and olive groves in the small agricultural valley north of Ensenada.
“If we wanted to use all the treated water in the city, we’d be hard-pressed to find places to put it, no matter how many green areas we had,” said Efraín Muñoz, head of the State Water Commission, Baja California’s water planning agency.
Miles from Tijuana’s crowded hillsides, winemakers in the picturesque Guadalupe Valley say they’re running out of water, and that is threatening the future of a region responsible for 90 percent of Mexico’s wine production.
The valley shares its wells with the city of Ensenada, and the growing demand for urban and agricultural uses has put unprecedented pressure on the aquifer.
The Guadalupe Valley would not be the first to use reclaimed water in its vineyards. Napa Valley has been using treated wastewater in some vineyards for at least a decade, said Jeff Tucker of the Napa Sanitation District.
Hugo D’Acosta, owner of the Casa de Piedra winery and a member of the Baja California Wine Growers Association, offers cautious endorsement for the pipeline proposal.
The reclaimed-water project could offer a solution, he said, “if and when it’s well-executed and meets the needs of the valley.”
D’Acosta and other vineyard owners have become increasingly wary of encroachment by housing developments and fear that without strict zoning regulations, the pipeline could encourage large-scale projects that destroy the valley’s vocation.
“I see it as feasible, but also very dangerous,” D’Acosta said of the proposed aqueduct.
This is not the first proposal aimed at using Tijuana’s wastewater. A U.S. company, Bajagua, for years proposed building a treatment plant in Mexico with $170 million in U.S. government funds, then selling up to 59 million gallons of reclaimed water a day. But the San Marcos company’s much-debated proposal failed in 2008 when the International Boundary and Water Commission opted to instead upgrade its existing San Ysidro treatment plant that treats 25 million gallons of Tijuana sewage a day.
Collecting and treating Tijuana’s sewage has been the subject of binational efforts for decades. The city’s spills and overflows risk contaminating San Diego County beaches and threaten the Tijuana River estuary, a federally protected wetland. Although dry-weather flows have largely been eliminated, cross-border sewage flows during wet weather continue to shut down South Bay beaches.
Last year, officials on both sides of the border celebrated when Tijuana’s state-operated utility, the CESPT, inaugurated the Arturo Herrera sewage treatment plant in eastern Tijuana.
The opening launched Tijuana’s first comprehensive wastewater-reuse program, and the inauguration of a pipeline carrying 470,000 gallons a day from the plant to nearby Morelos Park.
The CESPT is completing a second treatment plant nearby called La Morita, and is planning a third one, Cueros de Venado. The three plants would feed the Guadalupe Valley aqueduct up to 25 million gallons a day of wastewater treated to a secondary level, which is acceptable for irrigation purposes.
Muñoz, the Baja California water planner, said the Guadalupe Valley pipeline proposal has a good chance of becoming a reality, but it faces several hurdles.
Because the state government can’t afford the project’s $169 million price tag, it is turning to the private sector. The winning bidder would recover its investment by selling the water. But to keep water rates down, federal funds are also needed, Muñoz said.
The state hopes to put to the project out to bid this year and begin construction in 2011, Muñoz said.
Before reaching the Guadalupe Valley, some of the water would be diverted to the Valle de las Palmas outside Tijuana, where a satellite city is under construction. Additional amounts would be delivered to agricultural communities along the way, with the remainder stored at a reservoir planned at the valley’s northern end, Muñoz said.
The water would receive further treatment before being delivered to growers, allowing it to be used in spray and drip irrigation systems.
Even with the Guadalupe Valley pipeline in the planning stages, Muñoz is looking ahead to a second project to use the rest of Tijuana’s treated wastewater.
He envisions a coastline pipeline that would supply communities with irrigation water for their green spaces.
“It would be much cheaper than the drinking water we are now using,” Muñoz said.
By Sandra Dibble, UNION-TRIBUNE STAFF WRITER