The most important practical and critical problem related to the performance of reservoirs is the estimation of storage capacity loss due to sedimentation process. The problem to be addressed is to estimate the rate of sediment deposition and the period of time at which the sediment would interfere with the useful functioning of a reservoir.
The technical and institutional performance evaluation of Geray Irrigation Scheme was made in order to identify management practices for implementation to improve the system operation and the performance of the irrigation system.
Annual extreme rainfall series of 1-3 day durations at stations located inside the Indus basin in India were subjected to statistical analysis in order to estimate point Probable Maximum Precipitation (PMP) and maximum rainfall of different return periods for the durations of 1-3 days.
A model is developed to understand the relationship between satellite-derived NDVI and rainfall data in a large tropical catchment. Two Fourier-based modeling techniques with a seasonal component, viz. a seasonal model (SM) and a linear perturbation model (LPM) are tested, and their performance in reproducing the observed NDVI was evaluated. The methodology makes use of 15 years of 10-day composite time series data of rainfall and NDVI, which is estimated from NOAA-AVHRR data, both of which constitute concurrent data from 1982-96.
Elevated arsenic in groundwater is the greatest environmental problem in Bangladesh. Spatial variability of arsenic in groundwater has been examined by semivariogram analysis that revealed high degree of small-scale spatial variability in alluvial aquifers. Small-scale variability of arsenic concentrations, indicated by high "nugget' values in semivariograms, is associated with heterogeneity in local-scale geology and geochemical processes. In unsampled locations, arsenic concentrations have been predicted using both deterministic and stochastic prediction methods.
Geographic Information System (GIS) was utilized to apply a modified DRASTIC method to assess the aquifer vulnerability to pollution of English Bazar Block of Malda District, West Bengal, India. In the western, central and southern parts of the study area the aquifer is prone to contamination. Therefore, in these regions pesticides, which may contain arsenic or arsenic rich groundwater, should not be used in irrigated land or mango orchards. In order to understand the reliability of the aquifer vulnerability, sensitivity analysis was carried out.
The Upper Tana River Basin is one of Kenya's most important natural resource bases. Its Masinga Reservoir supplies water and hydroelectric power for 65 percent of the nation. Unregulated deforestation and expansion of cultivation practices onto marginal soils has resulted in significant reservoir siltation,
The goal of this paper is to assess the impact of future climate change on the hydrological regime of the tropical Upper Suriname river basin (7,860 km2) located in Suriname. GCM based climate scenarios from the MAGICC/SCENGEN model and 14 hypothetical climate scenarios are used to examine potential changes in water balance components in the study area.
Any reduction in water spread area at a specified elevation over a time period is indicative of sediment deposition at this level. This when integrated over a range of water stages helps in computing volume of storage lost through sedimentation. This study relates to estimation of capacity loss due to sedimentation of Hirakud reservoir, located in Orissa, India.
