The rate of stream depletion caused by cyclic pumping from a well located in a connecting groundwater aquifer was studied. Equations were developed by applying superposition principles to analytical solutions for steady continuous pumping. Dimensionless plots based on these equations have been developed; one for dimensionless volume of stream depletion over a pumping cycle and another for maximum rate of stream depletion at a practical state of dynamic equilibrium. These plots provide a way to quickly determine the time at which a practical state of dynamic equilibrium is reached and the error in stream depletion rates produced by neglecting the nonuniform pumping rate within a pumping cycle. Analysis showed that the volume of stream depletion over a cycle ending at time t, is the same as the volume of stream depletion between the start of pumping and time t by a single period of pumping. Analysis also showed that under some circumstances, approximating the effects of cyclic pumping by a steady, continuous pumping at the equivalent cycle‐average rate is not adequate.

Rainfall is a key source to diminish the problem of water scarcity in the arid and semi-arid regions. Rainwater harvesting is considered an imperious tool for rainwater conservation. Locating the appropriate location for rainwater harvesting structure plays an important role to increase water availability and improve water resources planning. The main goal of this paper is to recognize the proper location for a rainwater harvesting structure using a suitability model generated with ModelBuilder in ArcGIS. Six thematic layers i.e. soil structure, slope, drainage density, vegetation cover, distance to the roads, and runoff depth, are considered to find the proper site for rainwater harvesting structure. The result shows that 12% represents the suitable zone of the total study area, 42% represents the medium suitable area, and 46% represents not suitable areas to implement rainwater harvesting structure. The application of this scheme should maintain any policy adoption for site selection for rainwater harvesting.

Hasanlar Dam and Hydroelectric Power Plant are located on Küçük Melen Creek in the Western Black Sea Basin of Turkey. The dam was constructed in 1974 to provide domestic water needs of the Düzce Province, to supply irrigation water need, to control and mitigate floods and to produce hydroelectric power. This dam has been subjected to severe sedimentation since its construction in 1974. Therefore, bathymetric field survey studies were conducted to determine storage loss in the Hasanlar Dam reservoir by sedimentation. Bathymetric survey data from the reservoir site of the Hasanlar Dam were obtained in 1979, 1999 and 2014. Analysis of the bathymetric data, GIS and remotes sensing techniques showed that storage loss in reservoir active volume between 1974 and 1999 was 24% and between 1974 and 2014 storage loss was 26%. Analysis of the bathymetric maps also showed that sediment accumulation is severe near and around the dam body and the spillway whose discharge capacity was decreased by sediment accumulation. This is extremely critical because the flood of May 1998 caused the high risk of collapse of dam due to reduced capacity of the spillway. Remote sensing technique was used to determine the future deposition of sediment in the reservoir. For this purpose, 35 points in the reservoir area were determined by comparing the relative water depths and actual water depths using satellite image of the bathymetry in July 2017 and Lake Observation Station. High correlation (R 2 = 0.833) was calculated by using logarithmic nonlinear regression analysis between actual and relative water depths for those 35 control points. The average of absolute values of differences between the estimated and actual water depths was found as 1.06 m, and RMSE was calculated as 1.25 m. This analysis shows that in the future, remote sensing data can be used in the studies of determining the depth of water and the total sediment thickness. In addition, the volume of the entire reservoir can be predicted by measuring the actual water depth only at those 35 control points without making a bathymetric map of the whole dam reservoir.

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