Two groups of S&T students traveled to Bolivia this summer to help bring sustainable, clean water to two villages.

The first group spent months in Rolla designing a water distribution system for a subdivision in Erquis Sud. The system connects a well to a storage tank and uses PVC pipes to distribute water to houses in the subdivision. The planned well was dug deep enough to draw clean water that will require little or no treatment. The nine-member team also provided funds to bring electricity to the community to power a submersible pump for the system so water could potentially be pumped automatically up to the storage tank.

In Tacachia, the second group of 12 students continued efforts to bring drinkable water to the town, which previously relied on a spring at a nearby community for water.

The new water distribution system includes two hydraulic ram pumps, two settling tanks, two 2,500-gallon storage tanks, and in-home biosand filters.

“These pumps use the flow rate of the Rio Palca river — not electricity — to divert water from the river up a mountainside where settling tanks will be located,” says team leader Matthew Schultz, a senior in architectural and civil engineering. “This will lower the suspended solids in the water before it’s sent to the storage tanks. From there, water can be distributed throughout a PVC pipe system to each of the homes serving the 120 members of the community.”

Inside each home, a biosand filter will then make the water drinkable.

Last year, S&T students introduced the concept of biosand filtration to the community by installing 10 precast concrete filters. The team also constructed one of the needed ferro-cement storage tanks. Ferro-cement structures are typically strong and inexpensive to build, and made from a wire-reinforced mixture of sand, water and cement.

The students plan to build the two settling tanks and 30 biosand filters, using 160-liter plastic barrels for the bodies of the filters.