Since June 2014, our system has been technically complete!
Before we talk more about the status of the project and our most recent trip, we’d like to share some of our annotated as-built drawings. We hope that these will help you better understand what we implemented, and be used as a reference for our other posts. Click on the drawings to enlarge in a new window.
This was the layout of the water distribution system as built in 2008 by the African Medical & Research Foundation (AMREF). Water was drawn toward the kiosks from the Colonial line (“Kikumbulyu pipeline”, in the drawing) north of Usalama. The source of the water supply was, and still is, Umani springs, far west of Usalama. Though the tank (‘AMREF tank’ at D4) was meant to be filled and then distribute water to each of the kiosks, there was insufficient pressure to do so where the tank was located. Usually, only kiosks 1 or 2 were used, drawing water directly from the colonial supply. Kiosk 4 was occasionally used if there was enough pressure in the system for water to reach it. Between the connection to the Colonial line and the boundary of Usalama is the wildlife preserve, where elephants continually dig up and damage the pipe, causing enormous leaks in the system. This portion of pipeline was owned and maintained by Usalama, making them responsible for repairing leaks here.
The new pressurized water supply by KIMAWASCO (the local water authority, Kibwezi Mtito-Andei Water and Sanitation Company) runs parallel to the colonial line, and then turns and continues south along the Nairobi-Mombasa Highway. A branch that taps into this line at D4 and continues southwest is what Usalama’s system now taps into. The valve at D6 is closed, and the kiosks are now supplied by the new tank rather than the colonial line. Without their pipelines running through the forest any longer, Usalama’s water supply is not threatened by wandering elephants.
Close up of New layout:
Our new tank (“EWB tank”) is located at B4 in the drawing below and is connected to the KIMAWASCO supply by a 2” line. The KIMAWASCO tank at C1 is not part of our system, and supplies Kithasyu Village further west. From the new tank, water is distributed to the kiosks. At its higher elevation compared to the AMREF tank, water at the new tank has sufficient pressure to reach all of the kiosks.
Our tank is a reinforced concrete masonry tank designed to hold 40,000 liters of water.
The tank has an inlet for the KIMAWASCO supply, two outlets leading to the kiosks, an overflow, and a drain. A float valve closes off the KIMAWASCO supply inlet when the tank is full.
The tank also has an inlet that could be used for supplying water from the old supply with a booster pump. This was installed as an interim solution until the new KIMAWSCO supply became operational, but the community decided to forego the pump and wait for the new supply.