The impact of building development and renovation towards the hydrological condition in Java Heritage Hotel Purwokerto

¹ Master Program, Department of Civil Engineering, Universitas Jenderal Soedirman, Purwokerto, Indonesia
² Department of Civil Engineering, Universitas Jenderal Soedirman, Purwokerto, Indonesia
³ Department of Hydraulic and Ocean Engineering, National Cheng Kung University, Tainan, Taiwan

^* Corresponding author: annisaindahpratiwi@gmail.com

Abstract

The development at the Java Heritage Hotel Purwokerto will have a direct impact on the hotel’s water use. Because it results in reduce water catchment areas. Considering that the water source in this hotel uses groundwater from deep wells, the expansion of the built-up area this hotel will make the groundwater level decreases. The objective of this study was to investigate the effect of the development of this hotel on the local drop in groundwater levels and to propose solution for the area’s hydrological circumstance. To overcome the predicted increase in flooding and restore the groundwater level, water conservation measures are required, one of which is infiltration well technique. According to the result of the calculation, the calculate design rainfall for the 5 year return period is 68.66 milimeter per hour. Using the design of infiltration wells with a depth of 3 m and a diameter of 1 m, 162 infiltration wells for absorb roof runoff, 63 infiltration wells for absorb parking a lot runoff, 178 of infiltration well for absorb half the channel capacity and 356 wells for absorbing the total channel capacity. Meanwhile, pumping activities at the this hotel will result in a drawdown of 14 cm, and to return the groundwater level to its original state, a pumping time lag of 2.7 hours is required.