Indian Journal of Science and Technology

Abstract

Objectives: To propose new concept based on combination of GIS and statistical methods as a decision support tools for estimation of dam dimensions, reservoir volume and area. Methods/Statistical analysis: To accomplish this goal, firstly spatial data analysis on GIS was used to select the best location along the river for construction of the dam that has enough capacity for storage of required volume of water. Then Peaks Over a Threshold (POT) techniques was utilized to estimate 150-year flood discharge using daily discharge data from 1991 to 2013; and a simple overfall spillway was designed to release surplus waters from the reservoir. Findings: Results of GIS spatial analysis showed that a dam with crest height of 84m and length of 339m could be constructed that has a reservoir with 50.7 MCM storage capacities and surface area of about 1.44 km2 . Combination of GIS and POT method reveals that after release of surplus waters from the reservoir by the spillway, reservoir volume rises up from 50.7 to 51.6 MCM (increase about 900000 cubic meters). This is volume of the 150-year flood that can be stored in reservoir of the dam after release of surplus waters by the designed spillway. Application/Improvements: This study concludes that combination of GIS and statistical analysis is a powerful tool for finding the most appropriate situation for dam construction compared with reservoir surveys method.

Keywords: GIS, Peaks over a Threshold (POT), Flood control, Dam construction, Reservoir volume and area