Producing more rice with less water from irrigated systems

Irrigation management / Water use efficiency / Crop production / Water requirements / Water balance / Rice / Water distribution / Irrigated farming / Productivity / On-farm research / Irrigation scheduling / Groundwater / Conjunctive use / Rehabilitation / Modernization / Farmer participation / Farming systems / Irrigation systems / Crop-based irrigation / Asia / Philippines / Sri Lanka / Bangladesh / China / Malaysia / USA

Assessment of groundwater extraction in the Tadla irrigated perimeter (Morocco) using the SSEBI remote sensing algorithm

In the Tadla irrigation perimeter, farmers supplement their irrigation supplies with groundwater, leading to water table depletion in the area. An additional concern is the deteriorating water quality in the area. There is no regulation to control withdrawals of groundwater, and no data are available to quantify groundwater use. The paper demonstrates a method based on remote sensing techniques and field observation data to estimate the ground water use for the 2006 hydrological year. Calculations show that for Tadla, average groundwater use amounts to around 55% of the surface irrigation water use. This is substantial, and requires immediate attention. Policy recommendations are needed to control the use of groundwater and to reach an integral management with the canal water. For exact calculations, data on groundwater levels are needed

Hydronomic zones for developing basin water conservation strategies

Water conservation / River basins / Groundwater / Case studies / Irrigation / Water management / Water use efficiency / Sri Lanka / India / Egypt / Turkey / Kirindi Oya / Nile River / Bhakra Irrigation System / Gediz Basin

Planning groundwater use for sustainable rural development

Groundwater management / Rural development / Wells / Aquifers / Surface water / Conjunctive use / Irrigation water / Water pollution / Sri Lanka

The use and re-use of unsustainable groundwater for irrigation: A global budget

Depletion of groundwater aquifers across the globe has become a significant concern, as groundwater is an important and often unsustainable source of irrigation water. Simultaneously, the field of water resource management has seen a lively debate over the concepts and metrics used to assess the downstream re-use of agricultural runoff, with most studies focusing on surface water balances. Here, we bring these two lines of research together, recognizing that depletion of aquifers leads to large amounts of groundwater entering surface water storages and flows by way of agricultural runoff. While it is clear that groundwater users will be impacted by reductions in groundwater availability, there is a major gap in our understanding of potential impacts downstream of groundwater pumping locations. We find that the volume of unsustainable groundwater that is re-used for irrigation following runoff from agricultural systems is nearly as large as the volume initially extracted from reservoirs for irrigation. Basins in which the volume of irrigation water re-used is equal to or greater than the volume of water initially used (which is possible due to multiple re-use of the same water) contain 33 million hectares of irrigated land and are home to 1.3 billion people. Some studies have called for increasing irrigation efficiency as a solution to water shortages. We find that with 100% irrigation efficiency, global demand for unsustainable groundwater is reduced by 52%, but not eliminated. In many basins, increased irrigation efficiency leads to significantly decreased river low flows; increasing irrigation efficiency to 70% globally decreases total surface water supplies by backsim600 km3 yr−1. These findings illustrate that estimates of aquifer depletion alone underestimate the importance of unsustainable groundwater to sustaining surface water systems and irrigated agriculture

Food security and sustainable agriculture in India: The water management challenge

Sustainable agriculture / Food security / Water management / Water scarcity / Groundwater depletion / Waterlogging / Salinity / Soil degradation / Water use efficiency / Productivity / Equity / Irrigation water / Pricing

International Water Management Institute success stories 2000-2009

Research institutes / Research projects / Development projects / Water resource management / Water use / Multiple use / Food security / Soil conservation / Poverty / Farmers / Water harvesting / Water storage / Tanks / Land management / Drinking water / Domestic water / Groundwater management / Irrigated farming / Productivity / Wastewater irrigation / Water scarcity / Maps / Case studies / South Asia / India / Africa / Tanzania / Ethiopia / Thailand / Central Asia / Kyrgyzstan / Tajikistan / Uzbekistan

The Economics of Commonly Owned Groundwater When User Demand Is Perfectly Inelastic

This paper provides a theoretical analysis of the common-pool resource dilemma in extracting nonrenewable groundwater resources when water demand is perfectly inelastic. It complements the existing theory of groundwater use, which assumes away the possibility of demand perfect inelasticity. Under perfectly inelastic water demand, the common-pool resource dilemma is by-passed if groundwater users are equally productive in water use. If they are not, a new type of inefficiency can arise due to the lack of a rationing mechanism on the basis of productivity. Our analysis suggests that groundwater management research should pay more attention to water demand elasticity and productivity heterogeneity.common-pool resources, groundwater extraction, groundwater management, groundwater use, irrigation water demand, optimal control, pumping externality, water demand elasticity, Resource /Energy Economics and Policy,

Hydro-institutional mapping in the Steelpoort River Basin, South Africa

River basins / Institutions / Organizations / Private sector / Public sector / Local government / Mapping / Water resource management / Water policy / Legislation / Rural women / Constraints / Groundwater / Surface water / Water quality / Water use / Water users / Dams / Reservoirs / Large-scale systems / Irrigation management / Industrialization / Case studies / Operations / Maintenance / Canals / Conflict / Farmer-agency interactions / Policy / Water supply / Rural development

Policies drain the North China Plain: Agricultural policy and groundwater depletion in Luancheng County, 1949-2000

Agricultural production / Groundwater / Aquifers / Water shortage / Irigation efficiency / Agricultural policy / Crop production / Wastewaters / Water management / Hydrology / Economic development / Crop yield / Cotton / Wheat / Sprinkler irrigation / Water conservation / Water use efficiency / Pumping / Water balance / Vegetables / Rural economy / Irrigated framing