Charlotte MacAlister

Assessing the economic impact of a low-cost water-saving irrigation technology in Indian Punjab: the tensiometer

ABSTRACT This article assesses the impact of the tensiometer on the consumption of groundwater and electric power in paddy cultivation in Indian Punjab, and its subsequent economic benefits. We find that compared to the continuous flooding method, the tensiometer-based application of irrigation reduces water and power consumption by 13%, cutting variable costs by 7% without any yield penalty. If 30% of the paddy area is irrigated following tensiometer-based schedules, then the state could save a total of 0.67 million ha m of water and 1516 million kWh of electric power in 2010–2025, with aggregate economic benefits of US

Climate change and adaptive water management: innovative solutions from the global South

459 million.

Using the Climate Forecast System Reanalysis as weather input data for watershed models

Climate change is one of the most pressing threats to sustainable development across the globe. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2014) notes that 93% of the impacts associated with climate change will be felt in the water sector. Climate change is already altering precipitation patterns and snowmelt, impacting the frequency and magnitude of floods and droughts, and contributing to more extreme weather events and wildfires globally. Availability of renewable surface and groundwater resources is likely to decrease significantly in most arid and semi-arid subtropical regions, exacerbating competition for water between agriculture, ecosystems, industry and settlements (IPCC, 2014). Climate change is projected to lower raw and drinking water quality, due to interacting factors including increased sediment and pollutant loads due to heavy rainfall and breakdown of water treatment infrastructure during floods and extreme weather events, with flood hazards projected to increase across half the globe (IPCC, 2014). The populations of developing countries, primarily in the global South, are particularly vulnerable to the impacts of climate change on water availability due to high levels of exposure to water-related risks, limited coping capacity, and limited ability to recover from loss, often arising from non-climatic factors. The impacts of climate change are exacerbated by rapid population growth, rapid urbanization and chaotic economic development, particularly where water demands already exceed limited supplies. Climate change impacts destabilize development by affecting food security, health, infrastructure development and sustainable economic growth in developing countries. Simply put, climate change is not only a critical environmental concern but arguably the most urgent development challenge for the global South. Moreover, the voices of developing-country scientists – best placed to conduct research and present feasible local adaptation plans – are often silent in international public debate. The International Development Research Centre is a Canadian Crown corporation, established by an act of parliament in 1970 with a mandate ‘to initiate, encourage, support, and conduct research into the problems of the developing regions of the world and into the means for applying and adapting scientific, technical, and other knowledge to the economic and social advancement of those regions’ (IDRC, 1970). This special issue of Water International represents a sample of IDRC-supported projects on water