With a growing population and aging infrastructure, the city of Malang, Indonesia, was experiencing daily pipe bursts, with reservoirs dripping up to 20% of capacity at night and leakage rates of up to 400 liters per second.
Ranhill Water Services worked with PDAM Malang, PT Pancatama and Singer Valve to develop a solution to reduce pipe bursts, conserve water and provide improved service  to the 30% of customers who were being deprived of water due to the leaks.
The city was split into a number of control zones called district metered areas (DMAs), with a single source of water fed to the meter and a pilot-operated control valve at the source. Inflow and outflow were measured, allowing for pressure to be reduced and leakage to be controlled. The main distribution line had high pressure, but the addition of two pressure-reducing pilots in the main diaphragm-operated control valve set for daytime and nighttime pressures (high and low demand) helps control this.
To convince city water directors to approve the project budget, which called for the installation of 138 valves, PDAM Malang set up three DMAs near a problem reservoir. As a result, pipe bursts stopped, leakage was reduced and reservoir levels were maintained. Additionally, PT Pancatama conducted a test on a standard Singer diaphragm-operated pressure-reducing valve, which helped control pressure, reducing leakage and pipe bursts. The directors were convinced, the budget requirements were approved and the project moved forward.
After the first 42 valves were installed, the city experienced a 75% reduction of non-revenue water loss, a 300% improvement in pipe breakage and a 33% reduction in power consumption.
With increased reservoir capacity and reduced leakage rates, the city has been able to expand its distribution main and make water available to an additional 25,000 service connections—which amounts to approximately 125,000 people.
“Being an important part of a project as a manufacturer and supplying product application knowledge on our product that is truly making a difference, and being able to assist and supply water to thousands of Malang customers that never had the opportunity to have water available to them is a remarkable feeling and a great sense of accomplishment,” said Brad Clarke, vice president of sales and marketing for Singer Valve.