Abstract:
Flooding is a regular event in Khyber Pa.khtunkhwa, especially the areas settled along
the Rivers. During and after the flood, the main issue is the availability of clean
drinking water to the affected community. The floods of 2010 adversely affected the
infrastructure, water resources and the population of Charsadda District. Vast majority
of flood affected population had no access to clean drinking water and were forced to
rely on unsecure and contaminated sources. Keeping in view the severe situation of
drinking water quality, a study was developed with the objectives to (a) analyze/map
pre & post flood drinking water quality parameters (pH, alkalinity, total hardness,
electric conductivity, chlorides, sodium, sulphates, potassium, TDS, total plate count
and Coliform Bacteria) and identify suitable drinking water sites/sources. For this
purpose, pre and post event satellite remote sensing data (Landsat ETM+ 2001 and
GeoEye-1 2010) and DEM were used to map and extract flood extent, land covers and
topographic information of the study area. Similarly, post event water samples were
collected from various sources within and outside the flooded area. Lab tests were
performed and water quality parameters were compared with Pakistan Council for
Scientific & Industrial Research (PCSIR) standards. Department of Environment
(DOE) classification was used for developing the Water Quality Indices. These results
were compared with the pre:.event lab results for the same points in the study area and
analyzed with PCSIR standards. Water Quality Index based on the chemical
parameters revealed no change for alkalinity, chlorides, hardness and sulphates.
Sodium and pH shows an improve condition, but the rating of potassium, TDS, total
plate count and coliform bacteria have deteriorated. Comparison with the PCSIR
standards reveals that the water becomes totally unfit for drinking purposes due to
plate count and Coliform bacteria in part of Charsadda District. These parameters
were overlaid on flood extent map showing that not all the contamination was due to
flood water but samples outside flood plain also had values exceeding the permissible
limits. Water quality maps were generated showing classes as most suitable,
moderately suitable and unfit for drinking, as well as for suitable sites for clean
drinking water.
