On Climate Change and Jakarta Urban Water Supply
This posting is extracted from the latest paper written by Vincent Pooroe and me about climate change and urban water supply of Jakarta which is going to be presented in Young Scientist Workshop, one of the venues of International Water Week Amsterdam. Ironically, while this paper is being written, half of Jakarta residents are barely recovering from a water shortage due to a damage at Buaran retention basin.
For the last 15 years, water shortage is occurring annually in Jakarta. Interestingly, the event is occurred randomly both during the dry and wet season. Since 1998, the year of inception of water supply privatization, private water companies have been stating different reasons for water shortages; regular maintenance, ecosystem stress, infrastructural failures, and less water from Jatiluhur Dam. In respect of that spectrum of rationales for water shortages, networked infrastructure of water supply straddles through the rural-urban continuum and make it more complicated to analyze.
Some highlights in this paper are:
– The main problem at Jatiluhur Dam is competition between portion of water quantity for raw water supply and agricultural demands. When the elevation of the dam is severely decreasing during the peak of dry season, raw water supply will be affected disproportionately due to the infinitesimal quota. In the overall water balance, percentage of water channelled for Jakarta water supply is relatively small (6%) compared to portion of water from the dam directed for agricultural use which accounts for around 90% of total water balance.
– Ecosystem stress along West Tarum Canal mainly comes from fixed point sources of industrial and domestic waste. During weather transition period, the mixing of Tarum Canal water with the three bypassing main rivers induces high levels of turbidity. The alarming water quality thus results in increasing marginal cost to the point where plant loss is happening: more than half of raw water is constantly being wasted because the treatment cost is too high.
– Compared to infrastructural failures, climate change slightly affects the quantity of piped water system. The main reason of water shortage is arguably infrastructural failures while climate change merely attempts to amplify it.