Union-Tribune Editorial

Tijuana gets green with park fed recycled water
Ecoparque faces growth questions

July 30, 2001
By H.G. Meyer

The scenery along a riverbank brings this city's environmental issues vividly home. The Tijuana River's concrete bed is scattered with trash, including remnants of past sewage overflows. The hills are carpeted with houses and factories. And where development has not yet crept, the land is an arid brown.

But one slope blooms green. Known as Ecoparque, it is part park, part low-tech sewage processor. And in every way it is an attempt to solve Tijuana's sewage, open space and water supply problems in one environmentally sound swoop.

Staffed by Tijuana's College of the Northern Border, the facility is winning praise for its unique approach -- and concern from some who wonder if it will ever advance beyond a single demonstration project on the side of a hill.

The Mexican and American environmentalists who completed Ecoparque in 1993 turned household sewage into irrigation for the park's 15 acres. Visitors meander through groves of citrus trees, willows and jacaranda -- and among the screens and filters of a human-sized sewage plant.

Megaprojects to treat the sewage that flows into the Tijuana River, like the South Bay International Wastewater Treatment Plant at the border and another plant on the Mexican side, have cost American and Mexican taxpayers hundreds of millions of dollars.

"The general philosophy of waste-water treatment is build a big pipe, put it as far out in the ocean as you can and hope for the best," said Jim Bell, the two-time San Diego mayoral contender who was an Ecoparque construction manager.

But Ecoparque takes the "small is beautiful" approach. Completed at a cost of $600,000, its sewage plant transforms the flushes of 2,500 households into nourishment for bougainvillea, ice plant and dozens of other plant species.

The California Coastal Conservancy, the Mexican Council of Science and Technology, and other Mexican foundations and government agencies fund the project. With Tijuana's 1.3 million population expanding at an estimated 65,000 people per month, parks are an afterthought, said Ecoparque director Martin Medina. Tijuana's park space equals just 1.87 square meters (20 square feet) per resident, less than a quarter of U.N. recommendations, said Carlos Bransburg, spokesman for the city's Municipal Planning Institute.

Tijuana's three major municipal parks are irrigated by the city's increasingly precious drinking water, 90 percent of which comes from the Colorado River. In an era of tight energy supply, CESPT, the Baja California state water and sewer commission, spends 230 million pesos, or $25 million, on electric power to carry water to and from Tijuana, said CESPT spokeswoman Sara Leal.

At Ecoparque gravity, not electricity, is water's guiding force.

Waste water pours into the Ecoparque system's plumbing at four liters per second. Coarse screens filter bulky items. Then a finer sieve removes the most noisome solids, which are raked off and digested by worms to make fertilizer.

The water races through sluices before splashing into tall stacks called bio-filters, where special bacteria eat harmful microbes. In a final step, the sewage waits half a day in settlement ponds before being pumped uphill -- the only time electricity is used in the process -- to a tank, ready to irrigate the parque in Ecoparque.

The recycled water drains by gravity to wet the park, with the unused remainder re-entering the sewer line now cleaned to primary standards -- not safe for drinking or swimming but good for irrigation.

This spring, the Germany-based Bremen Partnership named Ecoparque runner-up for its prestigious urban environmental prize.

Despite the honors, observers question whether Ecoparque's test beaker is half-full or half-empty.

When founders built Ecoparque from the scraps of a similar project in the Tijuana River floodplain of San Diego, they envisioned a tree- by-tree, tank-by-tank revolution in the way Tijuana uses and disposes its water. Former Ecoparque director Oscar Romo says Tijuana has room for at least 40 more Ecoparques.

However, eight years after its ribbon cutting Ecoparque remains unique, and the 90,000 gallons it treats daily are less than 1 percent of the city's sewage output. During that time, the $324- million South Bay plant opened with the ability to process 25 million gallons a day. A proposed project called Bajagua would treat 75 million daily gallons in Tijuana, said Bajagua managing member Jim Simmons.

The Tijuana-based Seagulls Ecologist Group complained to the Frontera newspaper in June that local government hasn't pursued more Ecoparques.

Romo reports progress on other Ecoparque-inspired projects in Tecate, Matamoros, Camargo and San Luis Rio Colorado.

But he says, "To me, Ecoparque should jump from a pilot program to an authentic self-operating organization."

Leal said her agency would support new Ecoparques if they were proposed. Her agency donated the lab and provides the park with water sampling services.

A 1997 expansion proposal was certified by the Border Environment Cooperation Commission, but the related North American Development Bank never made a $180,000 loan because price ceilings on water in Tijuana made the project unworkable, Medina said.

Simmons said Ecoparque and all independent treatment ventures are hamstrung by a lack of sewer ratepayers in Mexico.

"The reason our project is feasible is because we have a customer, and that is the U.S. government," he said.

Looking at Tijuana's future demands for electric power, water and land, Medina is optimistic the Ecoparque model will become common.

"There are different ways to solve a problem, and Mexico tends to imitate what's in the U.S.," Medina said. "Mexico needs to pursue affordable, low-tech solutions."