Use Constant-Head Injection Test for In-Situ Estimation of Hydraulic Conductivity in Gravel Bed Rivers

In order to get more comprehensive understanding of hyporheic exchange in gravel bed rivers, we use modified Constant Head Injection Test method and developed a set of portable equipment to conduct field survey of hydraulic conductivity. Equipment includes a micro water pump powered by portable electricity generator, a manually driven permeameter made by steel pipe, measuring cylinder, and several accessories. Problems were detected during the trial in Tenryu River and Koshibu River and improvements were made afterwards