Balinese farmers' associations (subaks) that share water from common weirs and coordinate planting through a network of water temples. Lansing showed that temple-level scheduling balances water supply against pest control; the system survived a Green Revolution conflict and was listed by UNESCO in 2012.
A subak is a Balinese association of farmers who share water from a common source, usually a weir and canal, to irrigate terraced rice fields. Written references to the institution go back at least to the eleventh century, when inscriptions used the term kasuwakan, and the system is thought to be older. Subaks are linked to a hierarchy of water temples, from shrines at individual weirs and fields up to regional temples and the temple of Lake Batur (Pura Ulun Danu Batur), which Balinese regard as the origin of the island's springs and rivers. Ritual, agricultural calendars and water allocation are bound together under the Tri Hita Karana philosophy of harmony between people, nature and the divine.
The system became internationally known through the anthropologist J. Stephen Lansing, whose book Priests and Programmers (1991) argued that the water temples performed a real engineering function: coordinating planting and irrigation across whole watersheds. In 2012 UNESCO inscribed the Cultural Landscape of Bali Province, including subak landscapes and water temples, on the World Heritage List.
Each subak has its own name, membership and written or customary rules (awig-awig). A small subak is led by a single head (kelihan or pekaseh); larger ones have a board. Members meet in assemblies (paruman) to decide planting dates, maintenance work, contributions and fines, typically with one voice per member household. Water is divided by proportional weirs and dividers. Very large systems divide their subaks into upstream, middle and downstream groups that receive water in sequence.
Coordination above the subak runs through the temples. Lansing described how priests and congregations at regional temples set cropping schedules so that neighbouring subaks plant and fallow in a staggered but synchronised pattern. This involves a trade-off: if everyone plants at once, water runs short downstream; if planting is spread out too much, pests move from field to field and multiply. Synchronised fallowing across blocks of fields deprives pests of habitat while staggering keeps peak water demand manageable.
The public goods are water delivery, canal maintenance, pest control through coordinated fallowing and the ritual life that binds members. Labour and contributions come from members; the state's irrigation agencies built and rebuilt some major weirs but local operation remained with subaks. An estimated 1,559 subaks were recorded in 2019, compared with about 1,300 in the 1990s.
The best-documented conflict was with the Green Revolution. From 1971 the Indonesian government's BIMAS programme pushed farmers to plant high-yielding rice varieties continuously, with fertiliser and pesticides, and an Asian Development Bank irrigation project treated the temple system as religious rather than technical. Reports of disorder in water scheduling began in 1974 and pest outbreaks caused heavy crop losses in the late 1970s. Lansing and the ecologist James Kremer built a simulation model of irrigation and pest dynamics for 172 subaks in the Oos and Petanu watersheds; the model, which captures the trade-off between sharing water and synchronising fallow periods against pests, explained most of the observed variation in yields, indicating that regional coordination by the water temples mattered more than local factors. Their results were published in 1993. Government policy later allowed subaks to regain control of cropping schedules. The episode is now a standard example of planners undermining a working local system.
Current pressures are different: conversion of rice land to housing and tourism (the subak area near Denpasar fell from about 5,753 hectares in 1993 to about 2,444 hectares by 2018, according to figures compiled on Wikipedia from Indonesian studies), competition for water with hotels, falling water tables, land taxes and an ageing farming population. World Heritage status has brought visitors but also disputes over who benefits from tourism revenue.
Subaks have sustained intensive rice cultivation on a densely populated island for many centuries. Lansing and colleagues argued in 2017, using a model and satellite imagery, that cooperation spreading from pairs of farmers to whole watersheds creates a resilient bottom-up system that both increases and equalises harvests. Critics have cautioned against romanticising the temples, noting the role of state power, internal hierarchy and conflict in Balinese history, and that the model's assumptions simplify farmers' motives.
Centuries of intensive terraced rice farming coordinated from the bottom up. After the 1970s Green Revolution disrupted cropping schedules and pest outbreaks followed, research by Lansing and Kremer helped restore subak control. UNESCO World Heritage listing came in 2012. Rapid land conversion near Denpasar, tourism's demand for water and an ageing workforce now threaten many subaks. Founding year shown approximates the earliest written references (11th century).
Lansing and Kremer modelled 172 subaks on Bali's Petanu and Oos rivers: water-temple coordination of cropping patterns trades off water sharing against pest control, and tested against observed data the model explained most of the variation in yields.[1][2][3]
Green Revolution policies from 1971 promoted continuous cropping that disrupted subak water scheduling; pest outbreaks followed in the 1970s and the government later returned cropping decisions to subaks.[1][2]
Conversion of irrigated land threatens subaks: around Denpasar the subak area fell from about 5,753 hectares in 1993 to about 2,444 hectares by 2018.[1]