The EWB-USU Peru Team, in collaboration with The Chijnaya Foundation, is aiding the Andean community of Tuni Grande to improve and augment their potable water supply and provide sustainable engineering solutions to improve the quality of life for members of Tuni Grande.
Tuni Grande is located approximately 3 miles north of Pucará, on the Altiplano in southern Peru, and is home to just under 400 residents. Most of the community live in one of six 1.8 acre blocks. The community is mostly agricultural, with an obvious abundance of livestock. They collect and sell milk from cattle and also raise crops during the wet season. The community is also home to several families who earn income from local mines.
The principal drinkable water system for the entire community consists of an elevated storage tank fed by water pumped from a single well and a branching PVC pipe distribution system with a faucet for each household. Additional water can be hand drawn from two other frequently used “community wells” located near the south side of the community. Several community members further supplement this water with one or more of nearly two dozen other private or livestock wells. A submersible pump in a nearby well pumps into the community’s elevated storage tank. Due to the slow recharge rate of the well, this process takes approximately three days. Once the tank is filled, a valve is opened and the water is distributed to the community. Consequently, water is supplied to the community just twice a week. During these distribution events, water is distributed to each household simultaneously via a branching pipeline.
Before the 2012 implementation trip, there was a large degree of disparity between the water received from this distribution system. The eastern end of the community received the vast majority of the water released during each event, and members on the western end of the community received little or nothing.
Assessment trips were made in March 2010 and August 2011 to gain an accurate idea of the community’s needs. Detailed data were gathered on the community’s potable water system, including quantity and quality of sources and water use. The community members, especially the Water Committee, were regularly consulted and involved in data gathering and planning efforts. An implementation trip was made in August 2012.
The 2012 EWB-USU Peru team designed a new water supply system with three separate zones that can be turned on one at a time. This system uses a mainline that crosses under the road in a much more direct path to the community. When this mainline intersects the community, the main supply line branches into three separate zone supply lines, each containing an isolation valve. The three zones (east, central, and west) are shown below. The new, larger, and centrally located main supply line as well as the three zone solution were designed to reduce the level of inequity in water distribution.
In general, the changes made to the distribution system increased flow equality to the satisfaction of Water Committee and community members. In addition, members on the far eastern end of the community were not unhappy with the slightly reduced water flow they received on the new system. Remarkably, with the new system, much of the community turns now turns their faucets off after collecting water due to the vastly increased water flow. This has further increased water equality throughout the community.
Main Line Installation (click for video)
Christening the new valve box (click for video)
For more information, please see the post-implementation report.