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TECTONIC TURTLE PROJECT RESTORE H2O PROGRAM
TECTONIC TURTLE IS A REG. TRADEMARK & SERVICEMARK™ Trade & Service-mark (IP) License Registration
All Rights Reserved
TECTONIC TURTLE PROGRAM PLAN Copyright © MONICA KUHON│ DEC 2011
TECTONIC TURTLE PROJECT: RESTORE H2O PROGRAM Research Paper No.1, Title:: WATER IN BALI
By: Monica Kuhon & Joey Marissa; Photograph courtesy: Jez O’ Hare
I. Description of Water Resources Potential in Bali
Bali is an island located near the equator with two tropical seasons, which are the rainy season (November-April)
and the dry season (May-October). The rain fall measures between 1000mm in low altitude up to 3000mm in high
altitude. The southern area of the island is lower than the north, so the southern area of the island has less rainfall.
Although Bali has a high average rainfall of 2106mm which is higher than East Java’s average rainfall of 2080mm; the
potential of water surface and ground water in Bali is different than in Java, this is due to the difference of character
of the river flow and soil transmission between the two islands. (e.g. In Java most rivers are able to flow throughout
the whole year whilst in Bali some rivers run dry). This means that even though we are lucky enough to be provided
with more water, we must be careful as not to run out of water. We must take care of our water-usage, and not waste.
Water resources in Bali comes from the rainfall, a hydrological cycle (precipitation) which begins with the
evaporation of sea water that falls into the rivers to become surface-run-off, which the water then is absorbed into
the soil to become ground water.
The potential of surface water and ground water in Bali can be summarized as follows,
A. Surface Water:
i. Lakes: there are four main natural lakes in Bali
Lake Names Area of Water Capture
(km2)
Surface Area
km2)
Water Volume
(Million M 3)
1.
2.
3.
4.
Batur (Kintamani)
Beratan
Buyan
Tamblingan
105. 35
13.40
24.10
9.20
16.05
4.30
3.67
1.15
815.58
61.44
116.25
27.05
Total 152.05 25.17 1,020.32
The total volume of the 4 Natural Lakes in Bali is approximately 1,020. 32 million M 3.
ii. Man made lakes or dams (waduk), including: - Waduk Palasari, water volume: 8 million m3
Therefore the Total Volume of all Lake Water Resources in Bali becomes: 1,028.32 million m 3.
iii. River Water
Research has conclude a total of 162 rivers in Bali, which has been divided into 5 zones according to their
hydrologist area character similarities. The potential water resources that can be used from these
5 hydrological zones are: 49,837 million meter 3, including from the man made river branches constructed
in the Bukit Peninsula and the island of Nusa Penida.
Bali
River
Zones
Location , Number of Rivers & Characters
Area of Water
Capture /river
(km2)
Water
Volume
(Million
M 3/
second )
Zone
1.
Zone
2.
Zone
3.
Zone
4.
Zone
5.
Bordered by mountain range which runs from the most Western side to center of the
Island. This rivers zone begins on the east along the picturesque Antosari – Pupuan
Highway. Zone 1 consists of 28 Rivers, which flows continuously throughout the year
between the mountain slopes and graphical rice terraces. The river mouths ends in the
Indian Ocean on the South and West Coast of the island.
Is the largest zone, which starts at the Eastern boarder of zone 1, and runs North across the
mountain range. Begins with 33 Rivers, mostly very long with strong current, some of
these rivers widens and branches out as it reaches the low land until it reaches 54 rivers in
total- with river mouth ending into sea on the South and Eastern side of the island.
Located on the Eastern part of Buleleng District. With approximate 48 rivers, but one 3 that
has low capacity of running water throughout the year, while the rest run when there are
heavy rain fall during wet season. The potential of water resources in zone 3 is limited,
with minimal surface area of water flow.
Located of the Western part of Buleleng District. With approximately 33 Rivers in total, 18
of them which runs throughout the year, and the rest only during heavy rain fall. There
are 2 large rivers running on Zone 4, which is the Daya & Sabah Rivers, each with a water
capture capacity up to 80 km 2
Located in Klungkung - Nusa Penida Island, and the Bukit Peninsula on the south of of
Badung District, which consist mostly of Limestone Hills and cliffs. Since there are no
rivers with running waters throughout these areas, man-made river branch are constructed
here.
Water Volume capacity for Nusa Penida :
Water Volume capacity for South of Badung, Nusa Dua & Bukit Peninsula
8 – 50 km 2
Between 10 – 200
km 2
Maximum
10 km 2
0 – 80 km 2
1,717
2,587
36
594
0.1
0.2
Total Volume Capacity of River Water in Bali
49, 837
B. SPRING WATER
There are 500 potential main water springs in Bali which can extract up to 422.54 million cubic meters
No. District No. of springs Extraction capacity
Total debit (m3/s)
The volume per
Year
1
2
3
4
5
6
7
8
Jembrana
Tabanan
Badung
Gianyar
Klungkung
Bangli
Karangasem
Buleleng
37
82
21
33
26
86
71
144
0.11
3.26
0.51
0.98
0.82
1.62
3.91
2.19
3.46
102.80
16.08
30.90
25.86
51.08
123.30
69.06
TOTAL 500 17.40 422.54
C. GROUND WATER
Groundwater potential depends on the rock-formation and geological structure which is located under the earths
surface, which will influenced the aquifer under the soil surface. The geological structure of the island of Bali is
mainly made up of volcanic variety of volcanic topographies such as eroded early Quaternary volcanoes, active
stratovolcanoes, thick tephra deposits, pyroclastic flow slopes and closed caldera lakes. These various topographies
and a dense road network up to 1500 m high made Bali one of the ideal research fields for volcanic hydrology.
Research conducted in 1989 shown that only small areas has a water potential bigger than 10L/second while most
areas in the island less than 2L/second potential. Therefore it is only recommended to exploit maximum 10% from
the average recharge ground water capacity per year.
No. District Area (km2) Average
rainfall (mm)
Average recharge
per year
Limit of water
that can be
exploited= 10%
( M3/second) M3/s Mm
1
2
3
4
5
6
7
8
Jembrana
Tabanan
Badung
Gianyar
Klungkung
Bangli
Karangasem
Buleleng
841.8
839.3
542.5
368.0
315.0
520.8
839.5
1365.9
1957
2400
2001
2010
1653
1967
2039
1815
10.85
23.00
14.87
10.79
4.98
14.17
23.59
24.80
407
865
828
828
925
498
858
489
1,08
2,30
1,49
1,08
0,50
1,42
2,36
2,45
TOTAL 127.05 12,47
II. Usage of Water Resources in Bali
1. Water for Agricultural
The beautiful island of Bali is strongly dependant on their Subak irrigation systems, which is a traditional ‘water
agricultural management’. Agricultural is Indonesia’s second biggest money maker (their first is the oil and gas
industry).
To grow rice, you need a lot of water, but the water in Bali is also very important for their Hindu Buddha belief, as
water is a sign of purification ‚the Holy water‛. Therefore the Subak is also a ‘social religious organization’ as it is
the base of development for their rice paddy industry. The underlying philosophy guiding the Subak system is ‘Tri
Hita Karana,’ which is harmony between the Gods, the people and the nature. Therefore Subak is an age-old
irrigation system which has, over the centuries, proven to be near perfect, as it demonstrates how it's possible for
humans to live in harmony with nature through traditional methods and mutual cooperation, where Water temples
played a major role in hydrological and biological management. The primary role of water temples was in the
maintenance of social relationships between productive groups.
Idealized Map of Four Subaks with their Associated Waterways and Temples.
Subak are egalitarian, cooperative farmer’s associations that manage the flow of irrigation water into rice terraces,
and also coordinate agricultural rituals. But the average size of each subak is less than 50 hectares and 100 members.
When a single subak decides on its planting schedule for the next year (what to plant, and when), it sets in motion an
irrigation schedule for itself, which will also affect its neighbors. In other words, how much water one gets depends
in part on the irrigation schedules of one’s neighbors upstream.
Bali annual precipitation ranges from 1500 to 2500mm in the relevant areas, with seasonality significant but least
marked in the high-rainfall mountain areas that feed the rivers (McTaggart 1988). Nevertheless, rice farming on Bali
is so extensive and intensive that water is in limited supply on the terraced hillsides of this island, and
must be conveyed to fields via kilometers-long canal and tunnel systems. Since rice fields must be flooded at
planting time and kept relatively dry in the latter part of the growing cycle, farmers can deal with water shortage by
staggering the time at which they plant relative to other areas in the same river basin. This impetus to stagger,
however, is counteracted by another factor: if farmers synchronize planting, they synchronize fallow periods and
wet-dry changes and, since wet and dry fields are ecologically different, they can kill off infestations of wet- or dry-
field-specific pests by denying the pests the chance to ‚jump‛ to suitable adjacent fields (Lansing 1987)
According the Public Work Department (PU) of Bali from (1992)
- The amount of river water in Bali that can be used for agriculture, fisheries, and clean water distribution is
around 1.8 million m3, or aound 35% of the total available river water.
- The amount of river water that has been used is around 1.38 million m 3, or 76.5% from the total amount that
can be used.
- The research of ELC and ADC (1981) found that from the development of 35 subak, with the total area of
17,560 hectare, only 11,040 hectare (62.9%) can be used for wet rice planting twice a year; while 2,670 hectare
(15.2%) can be use for wet rice planting only 1 time a year plus additional 2 time of dry soil planting of other
crops like corn, coffee, chilly, peanuts, ect. The balance of 3.850 hectare (21%) can be used for 2 x wet rice
planting, and 1 x dry crop planting. This system of planting, is being used based on studying the water
resources measurements. Which measures the water availability and the irrigation water requirement on the
35 subaks, with ‚safety of supply‛ greater than 90% for 25 subaks , while for 5% are less then 90%.
- Research finds that there is enough supply of irrigation water during dry season, by using the method of
Taking turns in irrigation between land owners. Also the river water can be used repeatedly twice, since
The water will run from top to down stream.
The pictures above give you an idea on how the canal system looks like in Bali. I have also depicted the typical flow
division structures which work on the principle of continuous fixed proportional flows. The width of the diversion
structures is determined by the size of the land that is to be irrigated thereof. Farmers are not allowed to manipulate
these structures. However, in reality manipulation takes place.
As the illustration shows, farmers increase water flow into their own fields with a variety of methods.
Especially in the early stages of the rice cultivation water is the crucial variable. By closing other farmers’ inlets and
half of the weir just after the individual inlet (tembuku), the flow of water into the field is increased. As long as the
farmer stays next to the water inlet and returns the flow to normal before going home this manipulation is labelled
as ‚borrowing‛. Each passing farmer will be informed about the act of borrowing and assured that the flow will be
returned to normal. The borrowing farmer can explain why he has to borrow water and the other farmers can
remind him that he shouldn’t borrow water too long. This is not necessarily done verbally. Just seeing the borrowing
farmer is enough to remind him of the shame attached to stealing water. If the water flow is not returned to normal,
a farmer will be accused of stealing water. If this occurs the farmer will be warned and finally fined according to the
subak regulations. Though, these sanctions are hardly used because it is not the financial sanctions which the
farmers want to avoid, it is the fear of being known as a water stealer within the own social group.
Another possibility observed in the field to increase water flow is the sharing of surplus water. The farmer of one
subak makes an agreement with a farmer of another subak to use his off-flow water for his field in that he uses a
bamboo stick. The water which would usually flow into the off-flow canal to be used further down in another subak
is now diverted into the field of the neighbouring farmer’s field before flowing back into the off-flow canal.
2. Water for Clean Water
For the average Bali village community, clean water is generally obtained from shallow (individual home wells) and
surface water, like river, lakes and springs. Meanwhile in the urban areas, clean water are provided by the PADM
(State Owned Government Water Company), which uses ground water resources (deep well), springs and surface
water (rivers), which are being undergoes the water treatment process.
The usage of ground water in Badung District as well as Denpasar needs extra attention, since water exploitation
besides for clean water, is also being used for Industry. In Badung District and Denpasar, surveyed found more then
171 wells that has obtained permit, but has not be properly equipped with proper water debit measurement system
(Hassl et.al, 1992) , so we cannot count the usage.
Clean Water Exploitation of Fresh Water Springs, between 1988 – 2010
No. District Water Debit from
Springs (L / second)
Water Supply through Pipes
(L / second)
Without Spring & Surface
Water Pipes (L / second)
1988 2010 1988 2010
1
2
3
4
5
6
7
8
Jembrana
Tabanan
Badung
Gianyar
Klungkung
Bangli
Karangasem
Buleleng
110
3260
510
980
820
1620
3910
2190
0
98
5
30
64
46
64
162
0
261
5
61
97
117
196
474
24
117
28
93
19
83
82
68
32
137
26
107
22
98
96
93
Total 13400 469 1345 519 611
Clean Water Exploitation of Ground Water, between 1988 to 2010.
No. District 1988 (L/second) * 2010 (L/second) * Limit of Exploitation
1
2
3
4
5
6
7
8
Jembrana
Tabanan
Badung
Gianyar
Klungkung
Bangli
Karangasem
Buleleng
134
57
887
67
44
0
071
158
331
776
**734
532
60
0
154
325
1080
2300
1490
1080
500
1420
2360
2540
Total 1418 2212 12470
* Including clean water supplied by pipes from individual home wells, and wells in both urban and village areas
** Is required to improve the water pipe or other type of water distribution system, that can help minimize the
Clean water usage.
In order to meet the clean water requirement in Badung district, besides spring and ground water, the PDAM also
obtain 600 L / second - surface water of Tukad Yeh Ayung River, which will be develop as estuary dam. This dam
will consist of the excessive water from Tukad Badung River, and Tukad Mati River with a capacity o 600 L/second,
the provide clean water to the community, especially to meet the requirement for tourism Industry as well as the
main urban residential areas.
Notes*
Balinese farmers recognize, the irrigation schedules chosen by subaks also affect the life cycles of rice pests, like rats,
insects and diseases. Gusti Nyoman Aryawan, a Balinese ecologist, has shown that synchronizing irrigation
schedules over a sufficiently large area of rice terraces can control rice pests, since ‘if all of the fields in a sufficiently
large area are harvested at the same time, and subsequently flooded, rice pests are deprived of their habitat. If no
alternative hosts are available, the pest population will drop’ (Lansing, 1991: 121, cf. Aryawan et al., 1993)
In the 1970s, the World Bank and the Asian Development Bank attempted to improve on the system by introducing
the Green Revolution - Bali Irrigation Project. Without consulting the locals, they introduced a new water
distribution system and pesticides to Bali. The project almost destroyed Bali's farming and other ecological system.
The ‘Green Revolution’ brought the water temples into direct conflict with the goals of foreign engineers and
planners. ‘The powers of the water temples were entirely invisible to the planners involved in promoting the Green
Revolution, who regarded agriculture as a purely technical process,’ and that production would be optimized if
everyone planted high-yielding varieties of rice as often as they could. In contrast, Balinese temple priests and
farmers argued that the water temples were necessary to coordinate cropping patterns so that there would be
enough rice for everyone and to reduce pests by coordinating fallow periods.
Since the advent of high yielding ‘Green Revolution’ rice agriculture in the 1970’s, Balinese farmers have been
advised to supply all the potassium and phosphate needed by rice plants via chemical fertilizers. This policy neglects
the contribution of minerals leached from the volcanic soil and transported via irrigation systems.
Expert measured potassium and phosphate levels in unfertilized Balinese rice paddies, and found them to be
indistinguishable from those in fertilized paddies, and sufficient for high grain yields. Field experiments indicate
that most of the added phosphate flows out of the paddies and into the river systems, accumulating very high levels
before reaching the coast. Thus for the past 30 years, the ‘Massive Guidance’ program has instructed Balinese
farmers to purchase superfluous fertilizers, which flow out of the paddies and into the rivers and ground water.
Since most Balinese rivers are fast and short, a great deal of fertilizer reaches the coastal zone, threatening the coral
reefs (coral death and red tides have already been observed).
The real question is why these programs were implemented and sustained by technocrats for decades with so little
regard for local conditions?
Recommendation & Intervention
Mathematical apparatus of systems ecology simulation modeling have been useful in the defence of Balinese ‘traditional’
farming practices. For example, we were able to make a convincing argument against the continued use of chemical
pesticides, by modelling the effects of synchronized fallow periods on rice pests. Without the use of mathematical
tools, this analysis could not have been done, and Balinese farmers would still be told to spray organochloride
pesticides on their fields in the interests of national development.
References
Subak – Sistem Irigasi Tradisional di Bali (Sebuah Canangsari)
Publisher: Upada Sastra Denpasar
Ir. Wayan Windia, SU; Ir. Wayan Sudana, MS; I Ketut Wirta Griadhi, SH; Prof. Dr. Nyoman Sutawan; Ngakan
Made Samudra, SH; Ir. IGM. Suadnya; Ir. I Gde Pitana, MSc.; Ir. Nyoman Norken, MS; Drs. Ida Bgs. Pt. Purwita;
IGM Jelantik Sushila, BIE; Editor: I Gde Pitana
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Japan Y. SHBVIANO Department of Culture, Utsunomiya Bunsei College, Utsunomiya 320, Japan, O. SHBMMI
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Aryawan, I.G.N., I. N. Widiarta, Y. Suzuki and F. Nakasuji (1993)
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