Due to its strategic location, the population growth of Muntilan city is raising rapidly. Consequently, clean water demand is also increasing. However, the clean water demand is not available for 24 hours a day due to the development of the clean water is not in the right direction as initial design. In comprehend to the fact, a solution is required, especially by emphasizing to several strategies and solution alternatives. The objection of this research is to study the planning and development efforts taken by PDAM Tirta Gemilang of Magelang District, especially Kota Muntilan, in order to fulfill its service target. It is by viewing the technical aspect, particularly the pipe network efficiency.
In consider to the wide extent of the problem, limitations are required, that the study area consists of 28.61 km2, and predicted clean water demand up to the year of 2015. Data analysis is carried out based on available data. Especially for the pipe network simulation, WaterCAd Version 3 is used.
The simulation results show several junctions with pressure greater than 50 mH20 are found in the pipe network of PDAM Muntilan. To decrease the pressure, use of a pressure releasing structure can be alternative utilized. Due to the excessive water supply at ground reservoir of Gondosuli, there is a large amount of water during the existing condition. To have an efficient function of the reservoir, water supply from Semaren should be opened only based on the existing need. Mostly, water velocity at existing condition is still < 01 m/sec because the pipe diameter is wider than the size needed. However, this condition is still allowable since the flow is turbulence. There are no significant changes between the pipe condition in the year 2015 and the existing condition, in which water demand can still be fulfilled although the demand rises. Based on the simulation of the existing condition, the alternative model for the existing pipe which have technical advantages are the network pipes with smaller diameter adjusted to water demand, and smaller volume of Gondosuli ground reservoir. These may result in more efficient and economical cost of Rp 416,818,750. The allocation of this cost can then be utilized for the development of a wider network.