Testing a water monitoring tool to enhance potable water quality and safety in Lebanon

Abstract

This thesis develops and tests a valid Potable Water Quality Index (PWQI) to monitor the desirability, acceptability, and safety of distribution water supplies. It also assesses the quality of potable water distribution networks of Mount Lebanon, based on the developed PWQI, identifies problematic areas and recommends interventions. The study methodology consisted of collecting 20-25 random water samples from the each of the six Qadaas in Mount Lebanon (Aley, El Chouf, Baabda, Jbeil, Kisirwan, and Al Matn). Samples were collected during 4 rounds reflecting on the wet and dry season .The physical, chemical and microbiological quality was determined in the laboratory, based on standard analytical methods and in line with LIBNOR standards. The statistical analytical scheme consisted of: (1) Calculation of the proposed PWQI based on the equation developed by the Canadian Council of Ministers of the Environment (CCME) in accordance with LIBNOR water quality standards; (2) Validation and factor analysis was conducted (3) Contribution of quality parameters; (4) Parameter sensitivity analysis; by simple Regression by using backwards method. Results showed that the PWQI is more reflective of the water quality than the AWQI which only reflects on the acceptability of the water due to the unaccounted for microbiological profile, while the HWQI reflects only the health concern and does not reflect on water acceptability which is a major factor in determining water use by consumers. The UNEP WQI and the PWQI yield overall similar results in terms of water quality classification; still, the ranges seem to be more defined by the PWQI possibly as it includes parameters (TDS, total hardness, and free residual chlorine) that reflect more on the types of water sources, sources of pollution and the management of water supplies. The regression analysis showed that for HWQI, UNEP WQI and PWQI, [F3], the amplitude (the extent to which the failed test exceeds the guideline, showing by how much each parameter exceeded the guideline,