Sun, XXu, YJovanovic, NebojsaKapangaziwiri, EvisonBrendonck, LBugan, Richard DH2014-01-242014-01-242013-04Sun, X., Xu, Y., Jovanovic, N., Kapangaziwiri, E., Brendonck, L. and Bugan, R.D.H. 2013. Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa. Warer SA, vol. 39(2), pp 221-2300378-4738http://www.wrc.org.za/Pages/DisplayItem.aspx?ItemID=10203&FromURL=%2FPages%2FAllKH.aspx%3Fdt%3D%26ms%3D%26d%3DDocument+Type%26e%3DWater+SA+Manuscript%26start%3D1http://hdl.handle.net/10204/7170Copyright: 2013 Water Research Commission. Published in Water SA, vol. 39(2), pp 221-230Recharge estimation in arid and semi-arid areas is very challenging. The chloride mass balance method applied in western South Africa fails to provide reliable recharge estimates near coastal areas. A relationship between rainfall events and water level fluctuations (WLF) on a monthly basis was proposed in the rainfall infiltration breakthrough (RIB) model for the purpose of groundwater recharge estimation. In this paper, the physical meaning of parameters in the CRD and previous RIB models is clarified, and the RIB model is reviewed with the algorithm improved to accommodate various time scales, namely, daily, monthly and annual scales. Recharge estimates on a daily and monthly basis using the revised RIB approach in 2 study areas, one in a sandy alluvial aquifer (Riverlands) and the other in the Table Mountain Group (TMG) shallow unconfined aquifer (Oudebosch), are presented, followed by sensitivity analysis. Correlation analysis between rainfall and observed WLF data at daily scale and monthly scale, together with recharge estimates obtained from other methods, demonstrates that the RIB results using monthly data are more realistic than those for daily data, when using long time series. Scenarios using the data from Oudebosch with different rainfall and groundwater abstraction inputs are simulated to explore individual effects on water levels as well as recharge rate estimated on a daily basis. The sensitivity analysis showed that the recharge rate by the RIB model is specifically sensitive to the parameter of specific yield; therefore, the accurate representative specific yield of the aquifer needs to be selected with caution. The RIB model demonstrated in these two cases can be used to estimate groundwater recharge with sufficiently long time series of groundwater level and rainfall available in similar regions. In summary, the RIB model is best suited for shallow unconfined aquifers with relatively lower transmissivity; the utility of the RIB model for application in different climatic areas under different hydrogeological conditions needs to be further explored.enRainfall infiltration breakthroughRIBRIB modelGroundwater recharge estimationWater level fluctuationsWLFShallow unconfined aquiferGroundwater-level fluctuationTable Mountain Group aquiferArticleSun, X., Xu, Y., Jovanovic, N., Kapangaziwiri, E., Brendonck, L., & Bugan, R. D. (2013). Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa. http://hdl.handle.net/10204/7170Sun, X, Y Xu, Nebojsa Jovanovic, Evison Kapangaziwiri, L Brendonck, and Richard DH Bugan "Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa." (2013) http://hdl.handle.net/10204/7170Sun X, Xu Y, Jovanovic N, Kapangaziwiri E, Brendonck L, Bugan RD. Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa. 2013; http://hdl.handle.net/10204/7170.TY - Article AU - Sun, X AU - Xu, Y AU - Jovanovic, Nebojsa AU - Kapangaziwiri, Evison AU - Brendonck, L AU - Bugan, Richard DH AB - Recharge estimation in arid and semi-arid areas is very challenging. The chloride mass balance method applied in western South Africa fails to provide reliable recharge estimates near coastal areas. A relationship between rainfall events and water level fluctuations (WLF) on a monthly basis was proposed in the rainfall infiltration breakthrough (RIB) model for the purpose of groundwater recharge estimation. In this paper, the physical meaning of parameters in the CRD and previous RIB models is clarified, and the RIB model is reviewed with the algorithm improved to accommodate various time scales, namely, daily, monthly and annual scales. Recharge estimates on a daily and monthly basis using the revised RIB approach in 2 study areas, one in a sandy alluvial aquifer (Riverlands) and the other in the Table Mountain Group (TMG) shallow unconfined aquifer (Oudebosch), are presented, followed by sensitivity analysis. Correlation analysis between rainfall and observed WLF data at daily scale and monthly scale, together with recharge estimates obtained from other methods, demonstrates that the RIB results using monthly data are more realistic than those for daily data, when using long time series. Scenarios using the data from Oudebosch with different rainfall and groundwater abstraction inputs are simulated to explore individual effects on water levels as well as recharge rate estimated on a daily basis. The sensitivity analysis showed that the recharge rate by the RIB model is specifically sensitive to the parameter of specific yield; therefore, the accurate representative specific yield of the aquifer needs to be selected with caution. The RIB model demonstrated in these two cases can be used to estimate groundwater recharge with sufficiently long time series of groundwater level and rainfall available in similar regions. In summary, the RIB model is best suited for shallow unconfined aquifers with relatively lower transmissivity; the utility of the RIB model for application in different climatic areas under different hydrogeological conditions needs to be further explored. DA - 2013-04 DB - ResearchSpace DP - CSIR KW - Rainfall infiltration breakthrough KW - RIB KW - RIB model KW - Groundwater recharge estimation KW - Water level fluctuations KW - WLF KW - Shallow unconfined aquifer KW - Groundwater-level fluctuation KW - Table Mountain Group aquifer LK - https://researchspace.csir.co.za PY - 2013 SM - 0378-4738 T1 - Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa TI - Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa UR - http://hdl.handle.net/10204/7170 ER -