Methodology for the Estimation of Wetting Front Length and Potential Recharge under Variable Depth of Ponding

Abstract

A methodology for determining the length of advancement of wetting front and potential groundwater recharge under variable depth of ponding is presented. The methodology provides no restrictions to infiltration time period, depth, and nature of ponding and soil types. Performance of the proposed methodology has been compared with other models using the published laboratory and field experimental data. The quantitative statistics, namely, coefficient of determination (R2), index of agreement (d), and percent bias (PB), are utilized to assess the performance of the proposed methodology. Results show that the proposed methodology worked with the same potential as the numerically rigorous solution of the other models. The quantitative statistics R2 and d between the models’ estimates approached unity. Analyzed results shows that the proposed methodology for estimation of advancement of wetting front, cumulative potential recharge, and 5rate of potential recharge has a maximum PB of −12.98, −14.33, and 12.62%, respectively, in comparison to the other models, which is within permissible limit of 25%. The derived methodology is also successfully applied with 3 years (2006–2008) of field data from small recharge ponds located over a watershed in the semiarid region of India. The response of the methodology is found most promising for simulating the length of advancement of wetting front and corresponding potential groundwater recharge from small recharge ponds. Results of the comparative and field studies of the proposed methodology under variable depth of ponding over a variety of soils demonstrated the capability of the proposed methodology for their field uses to design artificial groundwater recharging facilities, irrigation systems, and resolving solute transport problems.