Open Access
Subscription Access
Sharp Variations in Groundwater Levels at the Same Location:A Case Study from a Heavily Overexploited, Fractured Rock Aquifer System Near Bengaluru, South India
Analyses of 83 borehole camera video scans revealed that (i) measured groundwater levels show variations of up to about 200 m, even in borewells located in close proximity to each other; (ii) water-bearing joints located at shallow depths in deeper borewells often produce cascades of water which flow down-hole till they meet the water level; (iii) the downward flow of recharging waters directly through the existing bore-well shafts leads to the formation of a dewatered zone below the recharge zone and above the saturated zone, and (iv) the borewells completed in the dewatered zone show a direct relationship between water level and well depth – deeper the borewell, deeper is the water level. Only the currently yielding borewells, with at least one water-yielding joint below the water level give a fair estimate of the regional groundwater table.
Keywords
Borehole Depth, Dewatered Zone, Fractured Rock Aquifer, Groundwater Level.
User
Font Size
Information
- Briscoe, J. and Malik, R. P. S., India’s Water Economy: Bracing for a Turbulent Future, Oxford University Press, New Delhi, 2006.
- Shah, T., The groundwater economy of South Asia: an assessment of size, significance and socio-ecological impacts. In The Agricul-tural Groundwater Revolution: Opportunities and Threats to De-velopment (eds Giordano, M. and Villholth, K. G.), CABI, Oxfordshire, UK, 2007, pp. 7–36.
- CGWB, Annual report for 2011–12, Central Ground Water Board, Faridabad, 2012.
- Alazard, M. et al., Investigation of recharge dynamics and flow paths in a fractured crystalline aquifer in semi-arid India using borehole logs: implications for managed aquifer recharge. J. Hydrogeol., 2016, 24, 35–57.
- Gleeson, T., Novakowski, K. and Kurt Kyser, T., Extremely rapid and localized recharge to fractured rock aquifer. J. Hydrol., 2009, 376(3), 496–509.
- Dewandel, B., Lachassagne, P., Wyns, R., Marechal, J. C. and Krishnamurthy, N. S., A generalized 3D geological and hydrogeo-logical conceptual model of granite aquifers controlled by single or multiphase weathering. J. Hydrol., 2006, 330, 260–284.
- Dewandel, B. et al., Development of a tool for managing ground-water resources in semi-arid hard rock regions: application to a rural watershed in South India. Hydrol. Process., 2010, 24, 2784–2797. 8. Maréchal, J. C., Dewandel, B. and Subrahmanyam, K., Character-ization of fracture properties in hard rock aquifer system. In Groundwater (ed. Thangarajan, M.), Springer, Dordrecht, The Netherlands, 2007, pp. 156–188.
- Rushton, K. R. and Weller, J., Response to pumping of a weath-ered–fractured granite aquifer. J. Hydrol., 1980, 80, 299–309.
- Rushton, K. R., Vertical flow in heavily exploited hard rock and alluvial aquifers. Ground Water, 1986, 24, 601–608.
- Barker, J. A., A generalized radial flow model for hydraulic tests in fractured rock. Water Resour. Res., 1988, 24, 1796–1804.
- Kukkillaya, J. P., Padmanabhan, K. and Krishnana, E., Use and limitations of short and medium term duration pumping tests in understanding hard rock fracture aquifers – an example from Kerala. J. Geol. Soc. India, 1999, 54, 267–277.
- Ballukraya, P. N. and Sakthivadivel, R., Analysis and interpreta-tion of electrical resistivity data from hard rock areas for ground-water exploration. Technical Report No. 33, Central Board of Irrigation and Power, New Delhi, 1984.
- Ballukraya, P. N., Groundwater over-exploitation: a case study from Moje-Anepura, Kolar district, Karnataka. J. Geol. Soc., India, 1997, 50, 277–282.
- Ballukraya, P. N., Over-exploitation and pollution of groundwater, a case study from Rasipuram area, Tamil Nadu. J. Geol. Soc., India, 2000, 56, 139–150.
- Van Tonder, G. F., Botha, J. F., Chiang, W.-H., Kuntsman, H. and Xu, Y., Estimation of sustainable yields of borewells in fractured rock formations. J. Hydrol., 2001, 241, 79–90.
- Van Tonder, G. F. et al., Manual on pumping test analysis in frac-tured rock aquifers. WRC Report No. 1116/1/02, 2002, ISBN 186845861X.
- Srinivasan, V., Thomas, B. and Lilee, S., Socio-hydrology of the TG Halli catchment in India – from common property to open ac-cess. In AGU Fall Meeting abstr., 2014.
Abstract Views: 360
PDF Views: 150