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Irrigation management
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Irrigation is the artificial exploitation and distribution of water at project level aiming at application of water at field level to agricultural crops[1] in dry areas or in periods of scarce rainfall to assure or improve crop production.[2] This article discusses organizational forms and means of management of irrigation water at project (system) level.
Contents
1History
2Water management
2.1Communal type
2.2Enterprise type
2.3Utility type
3Water pricing
3.1Tariffs
3.2Cost recovery
3.3Cost coverage
3.4Water User Associations (WUAs)
4Water delivery principles
4.1Rotational turns
4.2On demand
4.3Preferential rights
4.4Protective duty
5Water delivery practices
5.1Competition
5.2Tail-end problems
6See also
7References
History[edit]
Scholars such as Julian H. Steward and Karl August Wittfogel have seen the management of irrigation as a crucial factor in the development of many early states (hydraulic empires).[3] Water management[edit]
Communal maintenance of a diversion dam in a stony river bed, Baluchistan
The most important physical elements of an irrigation project are land and water. In accordance with the propriety relations of these elements there may be different types of water management:[4]
the communal type
the enterprise type
the utility type
From the point of view of water, the universal law of water balance must be obeyed for any Water Use System, including an irrigation system.
Communal type[edit]
Until the end of the 19th century the development of irrigation projects occurred at a mild pace,[5] reaching a total area of some 50 million ha worldwide, which is about 1/5 of the present area (see Irrigation statistics). The land was often private ha "privates" property or assigned by the village authorities to male or female farmers, but the water resources were in the hands of clans or communities who managed the water resources cooperatively.
Enterprise type[edit]
Slave labor in a cotton plantation
Labor in a sugarcane plantation
The enterprise type of water management occurred under large landowners or agricultural corporations, but also in centrally controlled societies. Both the land and water resources are in one hand.
Large plantations were found in colonised countries in Asia, Africa, and Latin America, but also in countries employing slave labor. It concerned mostly the large scale cultivation of commercial crops such as bananas, sugarcane and cotton.
As a result of land reforms, in many countries the estates were reformed into a cooperatives in which the previous employers became members and exercised a cooperative form of land and water management.
Utility type[edit]
Irrigation canals of the Gezira Scheme, Sudan, from space, 1997, with the utility type of management. The water comes from the Blue Nile
The utility type of water management occurs in areas where the land is owned by many, but the exploitation and distribution of the water resources are managed by (government) organizations.
After 1900 governments assumed more influence over irrigation because:[4]
water was increasingly considered government property owing to the increasing demand for good quality water and the reducing availability
governments embarked on large scale irrigation projects as they were considered more efficient
the development of new irrigation schemes became technically, financially and organizationally so complicated that they fell outside the capabilities of the smaller communities
the import and export policies of governments required the cultivation of commercial cash crops whilst, by controlling the water management, the farmers could be more easily guided to plant these kind of crops.
The water management signified a large subsidy on irrigation schemes. From 1980 the operation and maintenance of many irrigation projects was gradually handed over to water user organizations (WUA's) who were to assume these tasks and a large part of the costs, whereby the water rights of the members had to be respected.
The exploitation of water resources via large storage dams - that often provided electric power as well - and diversion weirs normally remained the responsibility of the government, mainly because environmental protection and safety issues were at stake.
In the past, the utility type of water management witnessed more conflicts and disturbances then the other types (see water delivery practices below).
Water pricing[edit]
See also: Water pricing Tariffs[edit]
Irrigation water has a price by which the management costs must be covered. The following tariff (water charge) systems exist:[6]
No tariff, the government assumes the costs
Tariff in labor hours, which holds mainly in communal types of management in traditional irrigation systems
Yearly area tariff, a fixed price per ha per year
Seasonal area tariff, a fixed price per ha per season with the higher price in the dry season
Volumetric tariff, a fixed price per m3 of water; the consumption is measured by water meters
Block or stepped-up pricing for water use per ha; the price increases as the water consumption per ha falls in a higher block.
The use of groundwater for irrigation is often licensed by government and the well owner may be permitted to withdraw only a maximum volume of water per year at a certain price.
Cost recovery[edit]
The recovery of water charges may be below target, because:[6]
The revenues accrue to a (government)organization other than the one responsible for the management
Farmers and water users have no say in the water management
Lack of communication between farmers and project managers
Poor farmers are unable to comply
Farmers do not receive water according to need; for example insufficient quantity and/or inappropriate time
Corruption at management level
Cost coverage[edit]
The cost recovery is often insufficient for full cost coverage, for example:
