Flood for thought
this is Baluchistan, in Pakistan's west. Infrequent floods, a hot, desert-like climate and an isolated location: Baluchistan's people have adapted themselves well to these disadvantages. They have used flood water irrigation (also called spate irrigation) to make the best of whatever little water nature sends their way. It is rather strange that flood water irrigation, which makes agriculture possible in a region as arid as Baluchistan, is yet to receive the attention it deserves from development officials. Archaeologists, however, have long known the value of harnessing flood waters for irrigating fields. Agriculture fed by floods is an ancient practice going back to 3000 bc when it provided the economic basis for early civilisations in West Asia, the Arab Peninsula and Egypt.
Spate irrigation can be of several types. These are spate diversion, where seasonal floodwaters are diverted from the normally-dry riverbeds, inundation canals that start flowing the moment the flood in a perennial river reaches a certain level and flood waters rise, where a rising perennial river overflows its banks and inundates the fields alongside. Baluchistan is familiar with these methods and also with the uncertainty that plagues all floods. And because floods are not really predictable, the risk of crop failure is formidable and the extent of land that farmers can cultivate in a year varies. Therefore, it is natural that the region's cropping practices, farm systems and social structures have been built keeping this uncertainty in mind.
Sailaba , as spate irrigation is known in Baluchistan, is quite different from run-off rainwater harvesting. In sailaba , the catchments are bigger and water is diverted from riverbeds, instead of being collected from hill slopes. In Baluchistan, it is common to find a combination of water harvesting and flood irrigation systems. For instance, in the mountainous regions, the land at the edge may receive water from both the sources. Further, fields are often deliberately kept at a slope so direct rainfall can collect at one edge of the field, making cultivation on a smaller portion of land possible even without floods.
The Sailaba systems vary widely throughout the region, the main parameters being cathcment characteristics, rainfall patter, location, level and so on. All these systems are, however, plagued by a certain uncertainties. These include recurrent uncertainty, related to variations in water availability and those arising out of the systems' configuration. The local people, however, have found ways to mitigate these and maintain agriculture to the best of their abilities. Farmers often save the surplus grains from a peak year, but this is not a common practice, partly due to inadequate storage facilities. Grains are stored either in elevated clay pots or buried and are vulnerable to rodent and pest attacks. A more common method is to buy disposable property that can be sold off in times of crisis. Farmers buy bullocks in a good year and, in the leaner months, live on the money from selling these. Diversification of the household economy is another method of coping with risks. Families generally depend on multiple sources of income, with livestock being a part of the flood irrigated farming system. Small ruminants often boost a family's income to overcome the dry years.
In these dry years, migration becomes increasingly common. In good years, the situation is different and labour demands peak, particularly during land preparation and harvest. This has led to flexible labour markets and, in recent years, mechanised traction. In several parts of Baluchistan, semi-nomadic populations have permanent relations with the flood water cultivators. For instance, the Brahui pastoralists from the hills of central Baluchistan come down to the Kacchi plains in the winters, where they assist in the harvest and and graze their animals. And in some cases, the cultivators themselves leave their flood water-irrigated highland wheat fields after sowing to work on sorghum harvests in the lowlands. They return once the wheat matures.
Another threat to agriculture is depopulation. In regions where farmers depend on each other for reconstructing barrages, the population figures might drop resulting in a freeze in the activities. To solve this crisis, Baloch and Brahui -- both highland tribes -- developed a conditional land tenure system. Under this, a person who develops land will acquire permanent cultivable right ( lathbandi ) and even has the freedom to sublease the land. If the landlord wants to discontinue the system, the tenant must be given a previously-agreed upon share of land. Likewise, if the tenant fails to cultivate, he will loose whatever rights he has on the land. But such practices are not universal. For instance, in Anambar plain in the upper reaches of the Nari river in Loralai district, landlords prefer to acquire bonded labourers.
Less water requires optimal usage. And this means better water management and distribution. So distribution of flood water irrigation systems are usually allocation rules-based and concern certain rules. These include construction of diversion structures such as bunds and obligations to break these, and certain 'privileged' land tracts which will be irrigated before others when spate flow is less. The sequence in which lands will be irrigated is another crucial factor. In Chandia, Sibi district, flood water is diverted from the Chakar River simultaneously distributed over three main branch channels: Kachwallah, Shaherwallah and Kandwallah, further distributed over 12 distributories. The sequence in which the lands within each channel are irrigated is fixed and small bunds or diversions are built into the channels to redirect the water into these fields. This simple system is also self-regulatory to a great extent. In years that see low floods, only a few tracts of land -- usually the low ones -- will be irrigated. If flood levels are high, the channels may overflow and the water might inundate all the tracts. Water is a rare commodity in Baluchistan and hence, it is impossible for farmers to divide pre-fixed volumes of water among themselves.
Less water also means contention over its distribution. The Haji Musa Bund on the Kud river in Las Bela district, is an instance. Here, the Kud river changes its course and created a new branch by eroding a substantial portion of the river's left bank. High floods that once threatened land on the right bank were now braided and flowed simultaneously in Kud's new left and old right branches. After a decade or so, the construction of a bund to prevent further erosion of the left bank was proposed. The right bank landowners were up in arms, as the bund, if built, would expose them to high floods again. They argued that the siltation, having developed naturally, should not be reversed. But eventually, the construction went ahead and the bund was built.
So far, agriculture in Baluchistan has been made possible only because of maximum community participation . Official intrusion in water issues is minimum. Of course, officials do intrude and are expected to do so when contention over water distribution leads to conflicts. But generally, the government maintains a status quo and leaves distribution of water and repair of the various irrigation systems to the people. In fact so far, the government has only once been directly involved in the management of spate irrigation systems. And despite the uncertainties that these irrigation systems are prone to, public investment in these during the past 30 years has been significant. Right now, only 35 per cent of the government's Provincial Irrigation and Power Department portfolio concerns spate irrigation systems. Despite optimal participation by the local people and investments, these irrigation systems are prone to failures. An evaluation of some 47 government flood irrigation schemes in the last three decades revealed that only 34 per cent of these still function. The rest have either become defunct or suffer from serious operational difficulties. The major flaw with these government-built systems and those erected by the people themselves has been the unsuitability of the engineering concepts behind them. Almost all systems aimed to control flood waters at a single point rather than managing the inherently varying flood rivers. Further, their designs hardly left any room for the uncertainties that plague these systems. Some of these were weak, and collapsed in the face of high floods.
The water-related conflicts plaguing the region are easily dispensable provided the people and the government adopt sensible and sustainable water conservation, management and usage plans. Like failures, Baluchistan has success stories, too. The flood management system in D I Khan district of Punjab in Pakistan is one such success story. Under this approach, the people try to manage the river rather than controlling it -- something they have tried till now. Of course, this needs a more comprehensive look at the river system and land formation processes. Wherever possible, farmers should continue to be the primary implementers under the river management approach. Other ways of avoiding problems would be to establish farmers' associations to represent different sections of a flood river, and to go in for well-planned organisational framework.