Irrigation expert Tushaar Shah, a Senior Fellow at the International Water Management Institute (IWMI), introduces conjunctive management as an opportunity for increasing irrigation efficiency in India which may be one of the country's best response to some of the major challenges in the irrigation sector.
What sparked your interest in irrigation?
Thirty years ago, I got involved in a study of decentralized irrigation service markets that were booming throughout South Asia. As an institutional economist, I found that these informal markets in groundwater irrigation service had profound and wide ranging productivity, equity, and sustainability impacts, and could be developed as an instrument of small farmer development.
What are the biggest challenges that India's irrigation sector faces today?
Some of the major challenges to India's irrigation sector include:
- Steady decline in the management and performance of all government- and community-managed surface and groundwater irrigation systems
- Regulating groundwater overdraft and quality deterioration
- Increasing the sustainability of groundwater irrigated agriculture
- Reducing power subsidies in groundwater irrigation
How are these irrigation challenges being addressed by government and other stakeholders?
Water, power, and other public services are in the domain of state governments, so responses to irrigation challenges vary from state to state.
In Punjab, Haryana, and Rajasthan, groundwater depletion is growing apace, power subsidies are mounting, and performance of canal irrigation is deteriorating. Improvements in other states can be observed, such as in Gujarat, where power subsidies are declining; groundwater balance is improving; and agricultural economy is booming.
In improving canal irrigation systems, many states are trying participatory irrigation management. To regulate groundwater overexploitation, governments are enacting new laws and regulations.
In the 12th five year plan, the Government of India is proposing a massive aquifer mapping exercise to promote participatory groundwater management. At the same time, massive investments are also planned for modernizing existing irrigation systems and constructing new ones.
Your recent work calls attention to understanding conjunctive management of surface and groundwater in India. What is conjunctive management and how can it help the irrigation sector?
Conjunctive management refers to the integrated and joint management of rainwater, surface water, wastewater, and groundwater resources for optimal socio-economic and environmental outcomes at the level of aquifer and irrigation system or a river basin. In contrast, conjunctive use refers to integrated use of surface and groundwater at the farm level. Conjunctive management works through structures and processes that guide individual water users to undertake conjunctive use.
Conjunctive management is at work, for example, when canal irrigation system managers purposely direct surface water deliveries away from water-logged areas to groundwater depleted areas; or when they suspend canal supplies during the rainy period to provide irrigation during dry season; or when they use treated urban wastewater to supplement fresh canal or groundwater supplies. In Gujarat state of western India, the Government has constructed a 600 km long spreading canal to use surplus flood waters from Kadana and Sardar Sarovar reservoirs in the south to recharge parched aquifers of North Gujarat to counter groundwater depletion and reduce power subsidies to irrigation. This is a good example of conjunctive management of surface and groundwater.
Conjunctive management is an important opportunity for increasing irrigation efficiency in India and may be the country's best response to runaway groundwater depletion, massive farm-power subsidies, drought and dry spells, and water quality deterioration.
What are the policy, institutional, and structural prerequisites for conjunctive management?
Sustained conjunctive management requires:
- high quality main system management in surface system
- well-managed and regulated surface water distribution systems
- a profusion of groundwater wells in command areas
- stringent enforcement of appropriate rules and norms for siting of groundwater structures
- a main system operational protocol (irrigation scheduling; rules for gate operation, real-time information and communication system, etc) that supports optimal conjunctive use
- effective network in agricultural extension.
Is conjunctive management already happening in India?
Yes and No. India offers many examples of conjunctive management of surface and groundwater, but because these have been occurring more by default and less by purposeful managerial action by water managers, it is difficult to consider them as such.
The Mahi Right Bank Canal System in central Gujarat is one example of conjunctive use by default. Commissioned in the 1970s, the canal irrigation system provided water to 250,000 hectares of land that became waterlogged and faced secondary salinization . Over the years, about 100,000 private tube wells were constructed and became the major source of irrigation water in command areas . These tube wells now serve as vertical drains - excellent substitutes for capital-intensive lateral drainage system. Waterlogged areas shrunk and agriculture boomed in previously unproductive regions. Irrigation efficiency, once defined as cubic meters/hectare of canal supplies was low; but when now measured as cubic meters/canal and groundwater irrigated area together, it is very high.
The vast plains of Punjab offer the same story. Massive waterlogging and secondary salinization in the 1950s and 60s have eased or been eliminated by private tube well development.
Down south in Tamilnadu, many canal irrigation systems have been over-extended so much so that canal water supplies needed to be rotated to different blocks of command areas. In some systems, all canal water is supplied to half a command area for a certain number of months; the other half uses well water while waiting for its turn to canal water privileges. In other systems, the entire canal network is run for a particular season, with canal water deliveries confined to left side in one year and on the right side the next year.
The proliferation of tube wells in command areas has made it possible for irrigation system managers to distribute available surface supplies over a much larger area than was earlier possible. Moreover, farmers value groundwater recharge from canal irrigation as much as - sometimes even more than - direct irrigation benefit.
In all these cases, conjunctive management of surface and groundwater has helped to cover larger areas, reduce waterlogging, and replenish diminishing groundwater resources.
How ready is India for sustained conjunctive management?
Indian agriculture is already plumbed for highly effective conjunctive management of surface and groundwater. All that the sector needs are reconditioned surface systems and a conjunctive management protocol.
India's conjunctive management potential has increased enormously thanks to a booming groundwater irrigation economy in the command areas of surface irrigation systems. However this potential is far from being fully utilized. Canal irrigation managers often ignore or are unaware of the benefits of conjunctive management. Moreover, poor rule enforcement in canal commands also makes conjunctive management difficult. As a result, conjunctive management in many Indian systems happens but largely by default through private entrepreneurial action by farmers.
Purposeful conjunctive management of surface and groundwater requires a mindset change among irrigation managers and tighter rule enforcement, besides, of course, modernization of canal and irrigation network. Institutions and management structures need to take up proactive and purposive conjunctive management of rainwater, surface water, wastewater, and groundwater.
Asia, with its ever-expanding population, needs major irrigation reforms fast or it could face food and water security crises. What advice or recommendations can you give to Asia's irrigation managers?
Irrigation planners and managers in Asia need to recognize that
- the era of construction of irrigation projects in Asia is rapidly coming to a close; the challenge now is to improve the management of public irrigation assets
- ignoring the role of private groundwater irrigation in canal command means missing out on a great opportunity for unlocking value from irrigation systems;
- Asia's semi-arid regions its own model of managed aquifer recharge and sustainable agricultural water solutions.
About the Champion
Tushaar Shah is a policy expert on irrigation and groundwater management and a Senior Fellow at the International Water Management Institute (IWMI) in India.
A development economist and strategic management specialist, Tushaar obtained his doctorate from the Indian Institute of Management at Ahmedabad. Tushaar's major contribution to irrigation development has been to improve the understanding of the groundwater economy of India. His extensive studies in the 1980s and 1990s on the structure, conduct, and performance of decentralized informal groundwater markets highlighted the nexus between power subsidies and groundwater irrigation.
He was honored with the Outstanding Scientist award of the Consultative Group of International Agricultural Research (CGIAR) in 2002. His most recent publication is Taming the Anarchy: Groundwater Governance in South Asia published by the Resources for the Future Press, Washington.
Prior to joining IWMI, Tushaar was formerly Director of the Institute of Rural Management at Anand in 1987-95 and consulted with the World Bank, the Ford Foundation, the Swiss Agency for Development Cooperation, and the Swedish International Development Agency. He also consulted extensively with private Indian foundations including the Sir Ratan Tata Trust and Sir Dorabji Tata Trust. He has also served on the boards of some 25 Indian nongovernment organizations and research centers.
Tushaar joined IWMI in 1999 as leader of the Policy, Institutions and Management program. In 2001, he took over the leadership of IWMI's new theme on Sustainable Groundwater Management and became Director of the IWMI-Tata Water Policy Program in India - the first ever collaboration between an international center and an Indian foundation. In 2005, he created two IWMI research projects funded under the Challenge Program for Water and Food: "Groundwater Governance in Indo-Gangetic and Yellow River Basins" and "Strategic Analyses of India's National River-Linking Project". Tushaar's research at IWMI contributed to the formulation of US$450 million groundwater recharge scheme for hard-rock districts by the Government of India and a US$270 million investment by the government of Gujarat in improved farm power infrastructure for sustainable groundwater management. His research-based recommendation for a US $ 2 billion National Irrigation Management Fund to incentivize Irrigation Service Fee Collection, Participatory Irrigation Management and irrigation service contracts is being considered for inclusion in India's 12th Five Year Plan.
Tushaar served on several committees of the Government of India for developing the irrigation component of India's 11th as well as 12th Five-Year Plans as well as in a committee of the Indian Planning Commission on Sustainable Groundwater Management.Stay up to date Subscribe to our newsletter and get the latest issues, news, events, jobs and data in your e-mail inbox.