Costs, regulatory gaps cited as main barriers to water reuse in Chile

Despite the appeal of water reuse in Chile to alleviate scarcity caused by drought, there are various legal and technical challenges, particularly when it comes to costs. 

“The technologies exist and have been tested and retested. The technical challenge is improving efficiency and reducing costs. That’s where most of the work should be focused,” María Pía Mena, vice president of the Chilean chapter of the Interamerican Sanitary and Environmental Engineering Association (AIDIS), said at a seminar in response to a question from BNamericas. 

Chile passed a law to reuse graywater in 2018, but guidelines are still being awaited from the health ministry (Minsal) regarding the water quality rules required for its application.

At the same time, the senate is studying a bill that would promote the reuse of treated wastewater that would otherwise be allowed to flow through marine outfall pipelines.

However, even if those regulations go into effect, Mena warned that there would still be administrative issues to solve, including how water reuse is promoted. 

“What specifically needs to be done is coordinated action, so that potential users are involved in projects,” she said during a water reuse seminar hosted by the advanced center for water technologies (Capta).

An estimated 22% of Chile’s urban wastewater ends up in the sea, while 77% goes into rivers, and less than 1% flows into lakes and irrigation canals, according to figures from the environment ministry (MMA). Only 6% of this volume is reused, mostly for agriculture (62%).

At the same event, the water transition advisor at the MMA, Pilar Berria, said that water reuse is a tool that could potentially be used by the soon-to-be created water basin councils, new public-private entities that are intended to improve coordination between the various actors involved in water management in specific water basins. 

“The idea of basin councils is to identify possible solutions to problems through shared objectives and reutilization is one solution,” she said.

Among their attributions, basin councils will be able to propose projects for funding through the country’s national regional development fund (FNDR).