The
analysis result by the Geographic Information System (GIS) describes
comparatively the risk of water availability reduction in Indonesia during
2010-2015 up to 2025-2030 period as effected by the climate change. The impacts
include:
1. Reduced Water Availability
There
are five risk levels with the highest level of water availability reduction is
found in the region of Java-Bali, particularly in several limited areas in the
northern and southern parts of West Java, central and southern part of Central
Java and East Java, in the capital city of North Sumatera, West Sumatera,
Bengkulu and Lampung (Sumatera); Bali, NTB (Nusa Tenggara) and South Sulawesi
(Sulawesi); whereas the high risk of water availability reduction is in about
75% of Java-Bali region; a minor parts in the northern, western and southern
region of Sumatera; some parts of Lombok Island (Nusa Tenggara), and South
Sulawesi (Sulawesi).
2. Flood
There
are five levels of flood risk and flood distribution, with the highest flood
risk is found very limitedly along the big rivers, particularly at the
downstream in Java, eastern part of Sumatera; West, South, and East Borneo;
East Sulawesi, and South Papua, whereas the high flood risk is found in the
same regions of highest flood risk, only with greater area size.
3. Drought
The
highest drought risk is found in general in the limited region in the central
part of Java; northern part of Sumatera, and minor part in Nusa Tenggara,
whereas the high drought risk is found in the greater area size in the central
part of Java, Sumatera, and Nusa Tenggara;
4. Landslide
The
highest landslide risk is generally found in the central and southern parts of
Java-Bali, central and western parts of Sumatera, the most parts of Nusa
Tenggara, and Sulawesi, and also central part of Papua, whereas the high
landslide risk is found along the highest landslide risk areas as mentioned
above with narrower areas.
5. Sea water intrusion
The
potential impact of sea water intrusion in line with the danger and
vulnerability of sea water intrusion is limited to several coastal areas,
particularly in the regions of Java-Bali (Jakarta, Semarang, Denpasar) and
Sumatera (Palembang and Padang). The risk of sea water intrusion is prompted by
the increasingly shallow sea water surface - sea water interface at the coastal
areas as well as related vulnerability including population density, land
usage, water requirement and deep water drilling. Sea water intrusion causes
reduction on water supply due to water quality deterioration and also land or
building foundation damage.