San José, Costa Rica, since 1956

Wastewater Treatment Neglected, but on Rise

Costa Rica’s drinking water system is among the best in Latin America. Thanks to a system of treating drinking water and, more recently, a national program that pays residents who live near aqueducts to conserve watersheds, the nation’s tap water historically has been safe and well maintained.

By most estimates, more than 95 percent of the country’s population has access to clean, drinkable water.

But the history of wastewater management is a very different story.

Septic tanks fill the underground landscape, and most existing sewage lines lead directly to rivers and streams, polluting the water and harming wildlife.

Approximately 5 percent of Costa Rica’s sewage water receives treatment before being returned to the water cycle.

A joke about the system says the Instituto Nacional de Acueductos y Alcantarillados (AyA), or the National Water and Sewer Institute, worked hard to develop the first “A,” but forgot about the second one.

While there is no single reason for the lack of wastewater infrastructure in Costa Rica, many experts believe it is due to the high cost and difficultly of maintaining treatment plants.

“It’s always been easiest and cheapest to install septic tanks and direct the pipelines to the rivers, so no one has invested in treatment plants.” said Luis Gámez, director of the Public Services Company of Heredia (ESPH), a private water company that operates with a public concession.

But even with the high price tag, AyA and other national agencies are seeking to unclog the cash flow and begin pumping money into wastewater management systems.

The National University (UNA), for example, completed construction of its own treatment plant in 2006 at a cost of some $258,000. UNA received financing from the Central American Bank for Economic Integration (BCIE) to build its facility.

ESPH is looking to upgrade Heredia’s treatment plan. The company already operates five small treatment plants that service the city of Heredia, but Gámez said the plan is to build one large facility that would have the capacity to serve a larger portion of the province of Heredia.

“A water treatment plan is no good if it’s small in scale,” Gámez said. “You have to seek many users to make it feasible.”

ESPH’s plan is to install 110,000 sewage connections in the province of Heredia over the course of 20 years. All of the connections would be fed to a new treatment plant.

The project would ring up a bill of approximately $200 million. ESPH received donations from the French government and financial support from the Interamerican Development Bank (BID) to conduct studies for the project, and Gámez said the Banco Nacional, a state-owned bank, has expressed interest in backing the material costs and construction of the project.

In the San José metropolitan area, AyA is following suit. The Legislative Assembly approved a contract for a loan from the Japan Bank for International Cooperation (JBIC) in October 2006.

The loan, for approximately $200 million dollars, covers the first phase of AyA´s two-part project. Stage one aims to increase the amount of treated water in the metro area to 26.8 percent by the year 2015, up from only 3.5 percent in 2007.

“This new system will form a great part of the development of the metropolitan area,” said Eduardo Brenes, director of the Regional and Urban Planning for the Greater Metropolitan Area (PRUGAM), an EU -sponsored program.

Brenes said that AYA didn’t neglect an environmentally friendly sewer network, but a system overhaul is needed due to drastic changes in Costa Rica during the past 20 years.

“Costa Rica has changed a lot since 1990,” he said. “We didn’t use to have the population and the development we have now, …and so we have to build a more extensive system to manage it all.”

While the cost of properly treating wastewater may be draining national pockets, Susana Lopez, a biotechnological engineer and manager of UNA’s treatment plant, said the long-term environmental cost of not providing treatment would be much worse.

She said one of the most common chemicals found in wastewater is phosphorus, a chemical typically present in detergents and disinfectants.

Without treatment, phosphorus and other nitrates drain directly into waterways from residences and industries, choking the channels of oxygen and killing fish and fauna.

“These chemicals affect the whole ecosystem in a negative way,” Lopez said. “It’s a cycle. What affects the rivers affects us.”

A good indicator of harmful liquids, she said, is the amount of bubbles a product produces. The more bubbles, the more harmful it is.

Lopez said the best way to keep bodies of water clean is to use biodegradable products containing fewer harmful chemicals. UNA strongly promotes the use of these products as part of its sustainable campus plan.

She admitted that persuasion of this sort requires time and education. Meanwhile, Lopez believes the best way to keep wastewater from harming the earth is to invest in treatment plants, regardless of the cost.

“We can work on producing less harmful products, but for now this is the only solution.

Next week: A look at the management of hazardous wastes.


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