Positive and negative aspects of water reservoirs

The main purpose of the research was to create a comprehensive methodology to assess, predict and prevent the consequences of the negative impact of water-reservoirs on the environment, provide the safety of population and infrastructure; to find a way allowing jointly realize the interests of hydropower and coast protection. To achieve this goal, the following methods were used: full-scale experiment, field-expedition surveys on operating reservoirs, informational analysis, mathematical methods of least squares, water-balance calculation, etc. New methods have been developed to determine the limiting volume of the accumulated sediment � silting prism (SP), the location of the equilibrium channel and hydrographic curves, echo-sounding, underwater relief planning, etc. The following activities were carried out in water objects of Georgia: instrumental monitoring of SP dynamics on active reservoirs and artificially created small hydro-objects; GIS analysis of the information base and archival materials; analysis of statistical series of observations. The mechanism of reservoirs sedimentation and spatial-temporal dynamics of the SP have been studied. The most effective way to minimize the negative consequences of sedimentation and increase hydropower efficiency is continually removed beach-forming materials from the reservoirs via the quarry system and fill degraded beaches with this material. The mechanisms of reservoirs' impact on climate and groundwater regime, population safety, and infrastructure were calculated, and their indicators and parameters were determined as a template. Criteria for selecting vulnerable areas of the seashore have been developed. Recommendation proposals have been developed for reservoir designers to select the site of their construction, type of regulation, and settlements� location.