Table of Contents

Abstract: That water is the world's most precious natural resource cannot be in doubt. Increasing demands for water due to growing population, increasing urbanization and industrial development exemplify its vital role in human life. Water touches us all, from the commercial private sector which either generates or uses the product potable water; through national and international government agencies (policy makers and regulators who attempt to maintain and improve our environment, whilst also making provision for the effective and safe treatment and distribution of potable water, and the collection, treatment discharge of our wastewater); to the general public whose lives depend upon the availability of sufficient quality and quantity.

Abstract: Among all the chemical substances available in the universe, water, with its deceptively simple formula H₂O, is the most discussed subject either in science or in philosophy [1]. If you are not convinced by this affirmation, a little experiment at no cost may help you change your mind. Just open your favorite web browser and type the word “water” in any search engine. When I have done that using Google, the number of hits was about 682,000,000 (please do not try to read all the pages). In fact, the only words that seem to beat water at this little game are “air” (770,000,000 hits with Google and 3,120,000,000 with Yahoo), and “food” (689,000,000 hits with Google and 3,820,000,000 with Yahoo). Of course this should not be a surprise, as breathing, eating, drinking just mean that you are a living entity. In fact extending the water search to “eau” (French), “wasser” (German), “agua” (Spanish, Portuguese) and “acqua” (Italian) leads to 978,900,000 hits under Google and 3,426,000,000 hits under Yahoo, showing now that water is about as important as food. After all, as everybody knows, “water is life”, and do we really have to read about one billion documents to know at least what water really is? [...]

Abstract: The economic value of tank irrigation water was determined through Contingency Valuation Method by analyzing farmers’ willingness to pay for irrigation water under improved water supply conditions during wet and dry seasons of paddy cultivation. Quadratic production function was also used to determine the value of irrigation water. The comparison of the economic value of water estimated using different methods strongly suggests that the present water use pattern will not lead to sustainable use of the resource in the tank command areas. Policy options for sustainable use of irrigation water and management of tanks in India were suggested.

Abstract: Water management issues continue to plague the western United States, including rapid population growth, degraded aquatic ecosystems, unfulfilled claims to American Indian users, the threat of global warming, an economic recession, and many other issues. This essay outlines some advantages of market-driven reforms to the management of water resources in the western USA. Historical and contemporary western water resource issues are examined from economic, environmental, and social viewpoints. In all such contexts, it is argued that regulated water markets provide flexible and just solutions to western water dilemmas, and reallocations may provide much-needed additional water supply.

Abstract: Daily rates of whole tree water use were measured in a homogeneous 7-year-old plantation over 84 days. Two trees were selected in the two most contrasting ends, i.e., with mean water table at -1.5 m and -3.5 m. Results showed that the mean tree water use was close to 80 dm³ day^–1 with a small mean difference between the two sites (5.4 dm³ day^–1, about 7%). Higher daily variations were observed on a single tree over the season (from 17 to 138 dm³ day^–1). These fluctuations could be modeled using linear regressions on the vapor pressure deficit (VPD). Results also indicated decreasing sap flux densities with radial sapwood depth and that the whole tree water use could be estimated from the sap flux densities measured at the 0–2 cm depth.

Abstract: The optimal management of a potable water distribution system requires the control of the reference (standard) data, the control points, control of the drainage parameters (pressure, flow, etc.) and maintenance parameters. The control of the mentioned data defines the network learning process [1]. Besides classic IT functions of acquisition, storage and data processing, a geographical information system (GIS) can be used as the basis for an alarm system, allowing one to identify and to localize the presence of water leaks in the network [2]. In this article we propose an algorithm coupling the various drainage parameters for the management of the network. The algorithm leads to an optimal management of leaks. An application is in progress on the primary network in the region of Bonaberi in Douala, the largest city of Cameroon.

Abstract: A water balance model was developed for Bung Boraphet reservoir, a large flood plain lake in Thailand, from daily measurements over three inflow outflow cycles between 2003 and 2006. Measurement error was 10% (as one standard deviation) of the total measured volume. The specific yield from the Bung Boraphet catchment was 3.9 m³/ha/yr and surface water inflow from the local catchment was the largest gain term and evaporation was the largest loss term in the water budget. Irrigation was the second largest loss term and dry season demand exceeded the storage supply. Uncontrolled extraction of water for irrigation is regarded as a threat to the reservoir fishery, although the increasing drawdown range may benefit wetland biodiversity. Sustainable management of the Bung Boraphet wetland will depend on careful management based on an informed understanding of the ecohydrological requirements of all wetland uses. Water balance models like this one are recommended as a tool to allocate water equitably and in ways which can be integrated across the Chao Phraya basin.