Water leakage paths in the Doosti Dam, Turkmenistan and Iran

Abstract

The Doosti Dam, with a reservoir capacity of 1,250 million cubic meters, was constructed on the Harirood River at the border of Turkmenistan and Iran. The reservoir is in direct contact with permeable formations on the right abutment of the dam including the Neyzar Sandstone, the Kalat Limestone and the Pesteleigh alternative layers of marlstone and sandstone. After the reservoir impoundment, several new springs and seepages emerged from these formations and the alluvium. The amount of leakage increased with the rise in reservoir water level. Fifteen kilograms of sodium fluorescein were injected into a 113-m deep borehole intersecting three permeable sandstone layers of the Pesteleigh formation. Dye was detected downstream of the grout curtain in boreholes and springs that were in direct contact with parts of the Pesteleigh formation having the same sandstone layers as the injection borehole. The dye velocity was in the range of diffuse flow, confirming the good performance of the grout curtain in the Pesteleigh formation. No dye was detected in the other formations because the injection borehole was not in direct contact with these formations. The hydraulic relation of the other formations with the reservoir was determined by considering direct contact of the formations with the reservoir, emergence of new springs and seepages after reservoir impoundment, correlation of time variations of the springs discharge and the borehole's water level with the reservoir water level, and in some cases the hydrochemistry of the water. The results show that the Kalat and Neyzar formations are hydraulically connected to the reservoir, but the small amounts of leakage from these formations at a hydraulic gradient of 24% indicates good performance of the built grout curtain. The total reservoir leakage at maximum reservoir water level was 100 l/s which is insignificant compared with the 15 m 3 /s average annual release of the reservoir.

Rock Slope Stability and Water tightness Assessment of Arjo Didesa Dam site, Western Ethiopia

“…However, most of the dam constructed on volcanic and sedimentary terrains in different parts of the country have faced engineering geological problems such as leakage, reservoir siltation, slope instability, damages of spillway and dam body without giving their desired purposes (Haregeweyn et al 2006;Abdulkadir 2009;and Berhane et al 2013). Nowadays, leakage of water is a common problem almost in all the dam sites in the world (Mozafari et al 2011). Leakage problem may lead to water losses from the reservoir and slope instability problem of the dam body and dam abutments.…”

The Effect of Hydraulic Gradient and Pattern of Conduit Systems on Tracing Tests: Bench‐Scale Modeling

“…However, the approaches should be used in a systematic step‐by‐step manner at both regional and local scales (Mohammadi et al ). Tracing tests is one of the most practical and effective methods used to assess hydraulic and hydrogeological data of karst aquifers, especially groundwater‐flow velocities (Thrailkill ; Lee et al ; Mohammadi et al ; Mozafari et al ). In most instances a tracing test can yield more information than tens of boreholes (Quinlan and Ewers ).…”

Optimization of the hydrodynamic characteristics of a karst conduit with CFPv2 coupled to OSTRICH

“…Valuable information is obtained from the general methodology of karst study (Bakalowicz, 2005;Goldscheider and Drew, 2007) including 1) geological, geomorphological, and speleological investigations, 2) water balance studies, 3) spring hydrograph and time series analysis, 4) hydrochemical and isotopic methods (i.e., natural tracing), 5) artificial tracing, 6) analysis of ambient spatial and temporal variations of piezometer data, and 7) pumping tests. Although an integrated and comprehensive study requires the implementation of all these methods, dye tracer tests are specifically used to determine the hydraulic connections of karst features in a heterogeneous karst terrain (Borghi et al, 2016;Mohammadi et al, 2007b;Morales-Juberías et al, 1997;Mozafari et al, 2012;Smart and Ford, 1986). In order to obtain data for water movement and conveyance of pollutants for all hydrological and hydrogeological studies, dye tracer test is a well-known method (Kass and Behrens, 1998).…”