The Quality of Urban Domestic Water Wells in Nigeria Aondover Tarhule 1, R. Mundi 2,David Sabatini 3,, Y.J. Magaji 2, S.

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1 The Quality of Urban Domestic Water Wells in Nigeria Aondover Tarhule 1, R. Mundi 2,David Sabatini 3,, Y.J. Magaji 2, S. Aondokaa 2 1. Department of Geography and Environmental Sustainability, University of Oklahoma, USA 2. Department of Geography and Environmental Management, University of Abuja, Nigeria 3. School of Civil and Environmental Engineering, University of Oklahoma, USA

2 In Jigawa, cholera strikes, 20 die Victims bemoan poor health care as cholera claims lives in four local councils Number of Child Diarrhea Deaths Can Be Halved With Current Interventions, Experts Say ScienceDaily (Mar. 23, 2011) Deaths from diarrhea -- a major killer of young children in poor countries -- could be almost halved if already available interventions such as breastfeeding, hand washing with soap, and improved household water treatment were widely implemented. Just building a million latrines won't solve Africa's sanitation crisis Nigerian Children At Government Schools Suffer High Burden Of Intestinal Worms ScienceDaily (Jan. 30, 2008) Intestinal worms are more common in Nigerian children attending government-owned schools than those attending private school, and the water supply and sanitation are worse in the government schools, according to a new study. Nigeria: Gwagwalada Chairman Tasks Residents On Pit Latrine Abubakar Sadiq Isah 1 September 2011 Nigeria, Northern Borno: installing toilets to reduce blindness Posted on June 23, 2010 by westerhof Leave a comment PIT LATRINE TRAGEDY: Lagos Govt Pays For Boy s Burial

3 Context Nigeria s urban centers have weak institutions for environmental risk monitoring and regulation enforcement. Water supply is erratic, even in planned urban areas or neighborhoods. Many, especially poor residents, depend on hand dug wells from shallow aquifers on their domestic water needs Electricity supply is erratic and undependable

4 Nigeria by Numbers Indicator Total population using improved drinkingwater sources 2008, % (T/U/R) 58 /75/42 % of population using improved sanitation 32/36/28 facilities 2008, Under 5 mortality rate, Primary school enrollment 61 Life Expectancy 48 years Percentage of population below international 64 poverty line ($1.25/day; ) Rate of urbanization ( ) 4

5 Location of study sites

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7 Source: Pennsylvania Dept of Environmental Quality

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12 Hypotheses 1. Domestic groundwater sources will be contaminated. 2. Well points close to septic tanks (soakaways) will be more heavily contaminated with fecal matter. 3. The shallower the well, the greater will be the degree of contamination.

13 Site 2 (Makurdi) Wells Soak ways

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15 Hypothesis 1: Groundwater sources will be contaminated

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18 Site comparison

19 Cross correlation of measured variables E.coli Colifor m Depth ST-well E.coli Coliform Depth Lid or not? Lined? PH Alkalinity Hardness Nitrite Nitrate Flouride ST-Well Lid or Not Lined? PH Alkalinity Hardness Nitrite Nitrate Flouride Pearson-product moment correlation used ST-well is the distance between septic tank and well

20 Hypothesis 2: Well points close to septic tanks (soakaways) will be more heavily contaminated with fecal matter. Coliform count (1 ml) Distance to soakaway (m) Nitrate (1 ml) E. coli count (1 ml) Distance to soakaway (m) Distance to soakaway (m)

21 Coliform count (1 ml) Depth b.g.s. (ft) Well depth and contaminants Nitrate (1 ml) E. coli colonies (1 ml) Depth b.g.s. (ft) Depth b.g.s. (ft)

22 Comparison between lined and unlined wells Unlined Lined Note: Numbers on the Y axis are meaningful only for coliform!

23 Comparison between lined and unlined wells Uncovered Covered Note: Numbers on the Y axis are meaningful only for coliform!

24 Multivariate Analysis Results of stepwise (backward) linear regression analysis shows that: Variations in E.coli counts can be explained (R 2 =51%) by: Coliform counts (p<0.001) whether the well is concrete-lined or not (p<0.072) concentrations in Nitrite (p<0.016).

25 Summary A large number of urban residents in Nigeria depend on groundwater from open wells to supplement their supplies. All wells tested had values of key microbiological quality indicators (e.g. E.coli, coliform, Nitrate) far in excess of WHO recommended standards for drinking water quality. Proximity to septic tanks (soakaway) did not emerge as a statistically significant factor in water quality contamination.

26 Summary A different study design is needed to definitively identify well water contamination pathways. A possible contaminant source not investigated is introduction from above There is potentially a significant risk of drinking well water from open wells without some treatment. There is opportunity for social entrepreneurship that explores low cost measures of water treatment for urban Nigerians.

27 Acknowledgements Chris Cope Bob Nairn Mrs. Shanwa A. Pradeep Juddy Okpara Uvirkaa Akumaga Residents of the study sites Numerous field assistants