Physicochemical quality of drinking water sources in Ethiopia and its health impact: a retrospective study

Environmental Systems Research

Table 4 Median and %WSORL of selected physicochemical parameters of spring, tap, and well water samples

Source of water samples	Total number of sample	Selected physicochemical parameters
Source of water samples	Total number of sample	PH	Total hardness mg/L as CaCO₃	SiO₂ (mg/L)	Na⁺ (mg/L)	Ca²⁺ (mg/L)	Mg²⁺ (mg/L)	Cl⁻ (mg/L)	PO₄ ³⁻ (mg/L)
Spring water	179	6.93 %WSORL = 36.9	72.0 %WSORL = 23.5	41.36	25.50 %WSORL = 26.3	19.24 %WSORL = 20.7	5.70 %WSORL = 5.6	7.6 %WSORL = 1.1	0.05
Tap water	253	7.31 %WSORL = 15.0	76.0 %WSORL = 9.9	24.08	20.40 %WSORL = 7.9	20.84 %WSORL = 11.1	4.78 %WSORL = 3.9	7.2 %WSORL = 0.8	0.04
Well water	551	7.52 %WSORL = 11.4	140.0 %WSORL = 15.8	62.86	54.4 %WSORL = 25.9	35.27 %WSORL = 16.7	10.50 %WSORL = 6.2	12.0 %WSORL = 6.4	0.06
ES (2001) (MPL)	–	6.5–8.5	300	–	200	75	50	250	–

%WSORL percentage of water source out of recommended limit, MPL maximum permissible limit, ES Ethiopian standard