Abstract:
Water resources planning is usually based on limited and often inadequate data. Existing hydrologic data base may not be oriented to newly arising water resources development requirements It is intuitive that when situations arise which were not considered in the planning of water management systems, it is possible that the systems can fail to meet their design purpose. A major limitation of the existing methods of hydrologic data collection is that these can not provide time-effective data necessary for taking prompt action especially when the area covered is extensive. Hydrologic data measurement points are sparse in most instances. But most important is. hydrologic processes are phenomena that vary rapidly in space and time. Measurements of these hydrologic processes have so far been accomplished primarily by in-situ point measurements. This has required either a high dense network of in-situ observations, or more frequently, and assumption of uniformity or aherence to appriori knowledge of the variability in space and time.