Assessment of transmission losses and groundwater recharge from runoff events in a wadi under shortage of data on lateral inflow, Negev, Israel
✍ Scribed by Isabela Shentsis; Lev Meirovich; Arie Ben-Zvi; Eliyahu Rosenthal
- Book ID
- 101283367
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 316 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0885-6087
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✦ Synopsis
A hydrological±lithostratigraphical model was developed for assessment of transmission losses and groundwater recharge from runo events in arid water courses where hydrological and meteorological records are incomplete. Water balance equations were established for reaches between hydrometric stations. Because rainfall and tributary ¯ow data are scarce, lateral in¯ow, which is an essential component of the water balance equation, could not be estimated directly. The solution was obtained by developing a method which includes a hydrological±lithostratigraphical analogy. This is based on the following assumptions: (a) runo resulting from a given rainfall event is related to the watershed surface lithology; (b) for a given event, the spatial distribution of runo re¯ects the distribution of rainfall: and (c) transmission losses are uniquely related to the total in¯ow to the reach. The latter relationship, called the loss function, and the water balance equation comprise a model which simultaneously assesses lateral in¯ow and transmission losses for runo events recorded at the terminal stations. The model was applied to three reaches of the arid Nahal Tsin in Israel. In this case study, the transmission losses were of the same order of magnitude as the ¯ow at the major hydrometric stations. The losses were subdivided into channel moistening, which subsequently evaporates, and deep percolation, which recharges groundwater. For large runo events, evaporation was substantially smaller than the losses. The mean annual recharge of groundwater from runo events in the Tsin watershed was 4 . 1 Â 10 6 m 3 , while the mean annual ¯ow volume at the major stations ranged from 0 . 6 to 1 . 5 Â 10 6 m 3 . Once in 100 years, the annual recharge may be seven times higher than the mean annual value, but the recharge during most years is very small.