Investigating the Hydraulic Properties and Design Criteria for the River Subsurface Intake with a porous media without cut off

Surface and subsurface water collection in small seasonal rivers is very crucial, particularly in dry seasons. In this study a type of intake is introduced which acts as a river drainage network. An experimental model of the subsurface intake was constructed and the effective parameters such as upstream discharge, installation depth, and drain intervals were evaluated. The results showed that the water diversion was mostly influenced by the upstream flow rate. The very small drain interval reduced the discharge of each drain. It was also revealed that the total drained discharge in the very transmitting media was mostly controlled with the number of drains and drain interval did have a marginal effect, the total discharge of drains in length of 100 cm has increased 63% in comparison to the total discharge of drains in length of 50 cm, whereas this increase was about 90% in length of 150 cm comparing to the length of 50 cm. Finally the regression equations were developed to estimate the discharge of each drain based on dimensional analysis, which facilitate the design of this structure.