Empirical relationship between soil permeability and resistivity, and its application for determining the groundwater gross recharge in Marpoyan Damai, Pekanbaru, Indonesia

In this article, a novel approach to measuring the gross groundwater recharge rate over a district area is presented. It is based on soil resistivity measurements. It is nondestructive, and allows quick, low-cost mapping of infiltration over large areas, which makes it particularly relevant for land planning. An empirical relationship between soil resistivity, ρ, and permeability, k, must be established before the permeability is related to the gross recharge rate theoretically. The method has been applied in Marpoyan Damai, Pekanbaru, Indonesia. The empirical relationship between resistivity and permeability was determined as log k = −0.1588 ρ + 6.628. The administrative districts within Marpoyan Damai with the lowest and highest annual gross groundwater recharge rate were found to be Wonorejo (about 61,000 m³/a for a 0.3 km² drainage area) and East Sidomulyo (about 881,000 m³/a for 1.44 km²).