The study area comprises Okada Town and its environs located in the South Western part of Edo State in Nigeria. The study area is primarily, an agricultural and commercial area with prospects of becoming a big town with attendant water supply problems. The study identified viable sources for sustainable community based water supply with the objectives to determine hydraulic parameters of the existing streams. The method used to measure the stream hydraulic parameters was Current Meter Discharge Method. The mean dry weather widths are: Okada Stream (3.6m and 10.2m at narrow and upstream sections); Iguedo and Okhai Streams (10.6m and 2.8m at typical upstream sections respectively). The corresponding stream stages and discharges are: Okada (0.57m; 100,656m3/day); Iguedo (1.23m; 117,590m3/day) and Okhai (0.21m; 8,294m3/day). From the obtained, and plotted data, the derived stream stage-discharge equations of the form Q = CHn are: Q = 1.543H0.5 for Okada Stream; Q = 1.062H1.2 for Iguedo Stream; and Q = 0.1334H0.21 for Okhai Stream. This study established only 1-year hydrological frequency. A 5-year or 10-year return period is needed for greater risks from probable worst condition scenarios. The recorded maximum combined discharge was 552,441m3/day in September 2011 and minimum flow was 226,540m3/day in January 2012. The reliable yield is estimated at 103,886m3/day and maximum allowable abstraction is 81,455m3/day. The results show that the three source streams will be adequate for sustainable water supply for the study area.

Water quality is a worldwide concern especially water for human consumption. Regular monitoring and tools should be developed, to ensure continuous assessment of the level of concentration of chemical constituents prevalent in water. This will guide against health dangers and risks associated with water of low quality. The research focus on using semi-variogram models to measure the degree of spatial dependency of sampled boreholes for prediction of the concentration of water quality parameters at un-sampled locations because of the cumbersome nature of assessing the whole boreholes in Benin City. One hundred and ten (110) different domestic boreholes were systematically sampled and analyzed in laboratory for determination of the concentration of some chemical water quality parameters which include Electrical Conductivity (EC), Total Dissolve Solids (TDS), Bicarbonate (HCO3), Sodium (Na), Potassium (K), Calcium (Ca), Magnesium (Mg), etc. Laboratory examination of boreholes water quality parameters were carried out in wet and dry seasons. Geographical locations of sampled boreholes were also determined. The obtained experimental results were utilized in investigating the spatial structure of the boreholes using semi-variogram models which include spherical, exponential, Gaussian etc. Exponential model was the most fitted model. The borehole water quality parameters exhibited high degree of spatial dependency in EC, TDS, HCO3, Na, K, Ca. Mg, Cl, P, and NO3 in both seasons with ratio < 25% therefore, interpolation technique can be employed to produce spatial variation quality map of boreholes in Benin City as a monitoring technique to detect contamination or changes in water quality.

The study area comprises of Okada Town and its environs (having combined base population estimate of 78,000) are located in the South Western part of Edo State in Nigeria. The study area is primarily an agricultural and commercial area with prospects of becoming a big town with attendant water supply problems. This study assessed the adequacy of available streams as possible viable sources of water supply with the objective to assess the existing water facilities, capacity and production levels. And further, to carry out comparative analysis of projected target water demand and minimum stream flow. The study area falls under urban water schemes, although in terms of economic and commercial activities, it has the character of rural and semi-urban composition. The 20-year projected population of target water consumers is 124,800 using arithmetic growth rate pattern and 140,877 persons using geometric pattern, both with growth rate of 3%. The 20-projected ultimate water supply is 23,250 m3/day. The existing water schemes have total capacity of 7,600 m3 and effective capacity of 2,512 m3.The present water supply of 1,618 m3/day is very grossly inadequate when compared totarget water demand. Okada; Iguedo and Okhai Streams are the three source streams. The combined and reliable stream yields is226,534m3/day and 103,886m3/day respectively. The maximum stream abstraction is 81,455m3/day. Analysis of water demand, stream yield and projected water demands showed adequacy of the source streams as possible viable sources of water supply.

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This paper reviews water quality parameters and their health effects on humans with the objective of enlightening the public on drinking water guidelines, the focal point and protection measures. It is also intended to help evade the health catastrophe that manifests as a result of ingesting water containing substances in excess concentration of recommended limits. Sources of water are reviewed, including rain water, surface water and groundwater. The presence and level of the biological, physical and chemical constituents referred to as water parameters which determine its suitability for drinking were also reviewed. Biological parameters are microorganisms, while physico-chemical parameters include temperature, color, dissolved solids, cations, etc. Drinking water quality standards as well as the health impacts of water quality parameters were discussed. Some of the health impacts include water borne diseases, organ failures, cancer, neurological damage, etc. The paper concludes that microorganisms and chemical constituents in drinking water sources and supply can directly or indirectly impair the use of the water for human consumption. Recommendations were made including the disinfection of drinking water sources to prevent growth of disease causing organisms, hand washing to prevent infections including Covid 19 virus and laboratory assessment of water quality parameters to ascertain their conformity with drinking water standards.