DOMESTIC RECHARGE WELLS FOR RAINWATER-HARVESTING IN DENPASAR CITY, BALI - INDONESIA

Abstract

This research is to create the design of shallow recharge wells for harvesting rainwater in
Denpasar City, Bali-Indonesia. The growth of the tourism industry is increasing rapidly. It has been able to
accelerate the economic growth, but also followed by some negative effects, including rapid growth of
population, changes in land use, reduced the catchment area and groundwater exploitation for tourism
infrastructure development. The result showed that in several strategic areas have shown an indicator of
water crisis, especially in North and East Denpasar. Based on the permeability analyses, the recharge area
was in the north and a little part of west Denpasar. The rainfall was between 1500 - 1750 mm/year with 4 wet
months a year. The shallow groundwater level reaches 16.10 m below ground level in the North, while in the
West was 18.2 m with the maximum infiltration rate was 0.00000054 mm/sec. Based on those data, it has
been designed the ergonomics shallow recharge wells for rainwater harvesting to offset the domestic water
usage. The analyses showed that if all 220.150 households make at least one shallow recharge wells, it can
harvest rainwater about 222.40 l/sec, and is able to return about 63.87% of water which should be recharge to
the ground. In conclusion, making one-recharge wells for each household has not been able to recover the
domestic water usage. It is recommended to create another innovation for water conservation program such
as building the recharge wells along the drainage tunnel.