The Living Waters crew worked up a drinking water filtration system in Tobasco, Mexico (Credit: Living Waters for the World)
In Tabasco, Mexico, water is left undrinkable by mineral deposits in soil and a coastal aquifer that runs beneath the Yucatan Peninsula. Many communities can’t treat it and depend on trucks to bring in drinking water.
But for one small community there, a mission group helped reduce its dependence on outside water by setting up and donating a custom water filtration system. A church houses the system and gives treated water to those who can’t afford it at no cost. The water is otherwise sold commercially at half the price offered by other bottlers.
Living Waters for the World is a mission project of the Presbyterian Church – USA and is no stranger to water treatment projects. Having done similar projects across the world, engineers expected a standard visit and setup, but soon found water in Tabasco wouldn’t be that easy to treat.
“We had some critical water hardness – 120+ parts per million – and water softening was needed,” said Ralph Young, technical director at Living Waters.
Given the complexities of the treatments needed, Young and other project managers wanted to try a new approach: double disinfection using UV and ozone. As they found out, disinfecting the water after running it through filtration was the best approach.
“Disinfecting the water after filtration and then running it through ozonation, however, resulted in oxidation of the minerals in the water, giving it a translucent yellow appearance,” said Young. “No one would drink it.”
So they went back to the drawing board and added more water treatment equipment, namely for water softening and reverse osmosis.
After the water is filtered by passing it through three filters, it is softened, then run through reverse osmosis. The first filter is a 50-micron pleated filter. A 5-micron filter comes second, followed by a 0.5-micron filter. Young says 95 percent of waterborne cysts and chlorine-resistant organisms are taken out by the last two filters. The final filter also uses activated carbon to remove volatile organic compounds. Ultraviolet light provides added disinfection before the processed water is bottled for distribution.
Clean, treated water is pumped into a storage tank until it’s needed. To confirm that the water is potable, system managers test monthly for bacteria with Hach Whirl Paks.
Before final bottling, water undergoes one last round of UV disinfection. It is then sold commercially or given to the poor for free. Young says most of the proceeds go to buying filters and other supplies for maintaining the treatment system.
“We encourage them (the churches) to compete on price and we suggest that they sell their water for half the price of local bottlers,” said Young. “We’re not going to be here forever. That’s one of the keys to this ministry – they’ve got to be sustainable.”
That’s just one lesson from Young’s time with Living Waters, which has developed a system for successful water treatment projects over time, as well as a thorough training program for teaching volunteers what they need to know for setting up water treatment systems.
“We train engineers who put the pipes together, teachers and project managers who cover things like business plans,” said Young. “We’re building relationships with people.”
The project in Tabasco wouldn’t have gotten off the ground without local support. A conference there was the first step, as local church leaders drove – very long distances in some cases – to meet with representatives from Living Waters and request systems for their churches.
“The water operators conference was one of the most valuable parts of the trip. We get operators together to share stories, teach about maintaining systems,” said Young. “One of the systems had been taken over by a lady who operated it like a business. She had actually run off the local water bottler in her town.”
Top image: The Living Waters crew worked up a drinking water filtration system in Tabasco, Mexico (Credit: Living Waters for the World)