Estimating leakage rate from riverbed using diurnal temperature signals of bottom sediments (Heihe river, Inner Mongolia, China)

Abstract

Estimation of leakage from riverbeds is an important task to quantify the interaction of surface and groundwater and to perform effective water management under arid climate conditions, where the leakage from riverbeds helps to maintain the existence of riparian ecosystems. One of the methods to estimate the leakage rate from the riverbed is to use the daily temperature signals of riverbed sediments. In present paper, the continues measurements of riverbed sediments temperatures in the lower reaches of the Heihe river (North-Western China) are used to calculate the leakage rate from the riverbed. The obtained results of the leakage rate calculations are compared with the results of inverse problem solution on a onedimensional model of heat and water flow. Good agreement of the calculated and model leakage rates is observed when a significant distance is found between temperature sensors (≥ 0,3 m) and between temperature sensors and riverbed surface (≥ 0,5 m).