Applicability of a Surveillance Methodology for the Microbiological Safety of Well Water Supplies, in a Highly Vulnerable Hydrogeological Setting——A Case Study Based Findings from the West Coastal Area of Sri Lanka


A well surveillance study carried out in nine Divisional Secretariat Divisions on the west coast of Sri Lanka showed that 70.3% of 101 well sampling points were microbially contaminated with equal to, or greater than, faecal coliform grade C (11 - 100 cfu/100 mL). Due to the very vulnerable hydro-geological setting of the coastal sand, laterite and alluvium aquifers occurring in the study areas, the recommended safe separation distance between an on-site sanitation system and a well could not be achieved. Hence, a cardinal rule of well protection was observed to be broken at almost every well study site. The existing excreta disposal systems need to be improved or replaced with more efficient ones before the impact of other sanitary hazards at the well, and wellhead area, on the microbial quality of well water, can be determined and addressed. The published (WHO, 1997) sanitary survey forms for open dug wells and tube wells need to be modified in the context of the study areas described. Based on a comparison of three different statistical methods used to assess the relative significance of each sanitary hazard modification to the methodology for determining the sanitary hazard index (SHI) was prescribed.

Share and Cite:

S. Barthiban, B. Lloyd and M. Maier, "Applicability of a Surveillance Methodology for the Microbiological Safety of Well Water Supplies, in a Highly Vulnerable Hydrogeological Setting——A Case Study Based Findings from the West Coastal Area of Sri Lanka," Journal of Water Resource and Protection, Vol. 4 No. 11, 2012, pp. 899-912. doi: 10.4236/jwarp.2012.411106.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] C. R. Panabokke, and A. P. G. R. L. Perera, “Groundwater Resources of Sri Lanka,” Government of Sri Lanka Water Resources Board Report, 2005.
[2] Department of Census and Statistics, Sri Lanka, 2012.
[3] D. K. Todd and L. W. Mays, “Groundwater Hydrology,” 3rd Edition, John Wiley & Sons, Inc., New York, 2005.
[4] D. L. Jayasekera, “Impacts on Water Quality of Rural Coastal Aquifers Due to Population Growth and Land Use Exploitation: A Case Study from Kalpitiya Peninsula, Sri Lanka,” MSc Dissertation, Utah State University, Logan, 2007.
[5] D. D. Bhosale and C. P. Kumar, “Simulation of Seawater Intrusion in Erankulam Coast,” Undated.
[6] B. J. Lloyd and R. Helmer, “Surveillance of Drinking Water Quality in Rural Areas Longman Scientific & Technical,” Co-Published in the United States with John Wiley & Sons, Inc., New York, 1991.
[7] WHO, “Guidelines for Drinking Water Quality, 2nd Edition, Vol. 3 Surveillance and Control of Community Supplies,” 1997.
[8] ISO 9308-1, “Water Quality-Detection and Enumeration of Coliform organisms, Thermotolerant Coliform organisms and Escherichia coli,” Published in Geneva, Geneva, 1990.
[9] ARGOSS, “Assessing Risk to Groundwater from On-Site Sanitation: Scientific Review and Case Studies,” British Geological Survey Commissioned Report, CR/02/079N, 2000, 4411 p.
[10] S. Barthiban, B.J. Lloyd, and M. Maier, Sanitary hazards and microbial quality of open dug wells in the Maldives islands, Water Resource and Protection Journal, Vol. 4 No. 7, 2012, pp. 474-486. doi:10.4236/jwarp.2012.47055
[11] B. J. Lloyd and T. Boonyakarnkul, “Combined Assessment of Sanitary Hazards and Faecal Coliform Intensity for Rural Groundwater Supply Improvement in Thailand, Proceedings of a National Conference on Geologic Resources of Thailand: Potential for Future Development,” Department of Mineral Resources, Bangkok, 1992, pp. 17-24
[12] A. A. Cronin, S. Pedley, N. Breslin and R. G. Taylor, “Assessing the Risk to Groundwater Quality from Unsanitary Well Completion and On-Site Sanitation,” 2nd International Symposium on Ecological Sanitation, Luebeck, April 2003, pp. 431-436.
[13] G. Howard, S. Pedley, M. Barret, M. Nalubega and K. Johal, “Risk Factors Contributing to Microbiological Contamination of Shallow Groundwater in Kampala, Uganda,” Water Research, Vol. 37, 2003, pp. 3421-3429. doi:10.1016/S0043-1354(03)00235-5

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.