Abstract: The main source of groundwater recharge in arid area is river water seepage.An accurate calculation of streambed parameters is required in evaluating groundwater resources in arid region, and the streambed parameters include the vertical streambed hydraulic conductivity K and vertical river water seepage rate V.In this paper, a simplified seepage meter was described, and the equation was deduced for calculating the vertical streambed hydraulic conductivity in arid area.On which the streambed parameters in the northern piedmont of the Kunlun Mountains, an arid area in south Xinjiang, were measured.The results showed that the vertical streambed hydraulic conductivity in 18 tests varied from 0.07 to 1.03 cm·min^-1, and this method could be used to effectively measure the vertical hydraulic conductivity of streambed in arid area.According to the test results, the relationship between river water seepage rate and river water depth in arid area was summarized, and a formula to describe their relationship was proposed.The results showed that there was apositive correlation between the vertical seepage rate V and the vertical depth M of river water, but a negative one between the increase of seepage rate dVdM and the depth of river water.When M is deep, the growth rate dVdM of seepage rate tends to zero.The study is of great significance for evaluating groundwater resources in arid area.

Key words: streambed, vertical seepage rate, vertical hydraulic conductivity, arid area, Xinjiang