Design of Water Distribution by Using Umbulan Water in West Surabaya

Umbulan spring water would be used as raw water for clean water production by Surabaya City. Umbulan water would be sold in bulk for Rp3,300.00/m3 in 2019. The price would rise by 5.53% annually. The difference between Umbulan water price and PDAM Kota Surabaya tap water rates encouraged PDAM Kota Surabaya to plan using Umbulan water source. In its design, PDAM Kota Surabaya would make a special area that would use only Umbulan water as tap water. To maintain its quality, Umbulan water must be distributed separately from PDAM Water. There are two alternative plans to distribute Umbulan water. The first alternative was by isolating the distribution pipes in the planned area. The second alternative was by using new food-grade pipes without isolating the existing pipe. These two alternatives affect water flow pattern in West Surabaya. Customers in the planned area still doubted the quality of Umbulan water. However, customers in that area were willing to pay a higher rate as long as it would not increase more than Rp50,000.00 monthly. By using Umbulan water and not rising tap water's rates, PDAM Kota Surabaya would not experience any deficit until 2023. But, if PDAM Kota Surabaya increased tap water's rate, PDAM Surabaya would not get any deficit until 2030.