Groundwater quality assessment from Phalombe Plain, Malawi

Abstract

In the present study, groundwater samples were collected from ten boreholes in the Phalombe plain, Southern Malawi. The main objective was to assess the suitability of the borehole water for human consumption. Physicochemical and bacteriological parameters of the groundwater samples were determined using standard methods. Results were compared to the World Health Organization (WHO) and Malawi Standard (MS) drinking water guidelines to assess suitability. All analyses for physicochemical parameters were within acceptable limits except for fluoride concentration levels which were above WHO recommended limit of 1.5 mg/L in twoboreholes (Lihaka Primary School, 2.9 mg/L and Phalombe T.C, 2.0 mg/L). Trace metal contamination was below detection limits with atomic absorption spectrometry. Feacal coliform units exceeding WHO tolerated limits of 0 cfu/100 mg/L were observed in five groundwater samples from Lihaka Primary School (11 cfu/100 mL), Migowi trading center (4 cfu/100 mL), Phalombe T.C (77 cfu/100 mL), Thetheleya Village (73 cfu/100 mL), and Mpasa T.D.C (102 cfu/100 mL) boreholes. It was concluded that not all the borehole water is safe for human consumption. The presence of feacal coliform in some boreholes is indicative of health risk to the inhabitants of the geographical location. The study recommends mobilization of onsite possible means of treatment of groundwater such as boiling and use of chlorination tablets so as to prevent possible adverse health effects.

Keywords: Bacteriological, Borehole, Malawi, Phalombe Plain, Water quality, WHO/MS drinking water guidelines