PHYSIOCHEMICAL PROPERTIES OF BOREHOLE WATER IN ILORIN METROPOLIS
1.1 Background Study
Water is life and is known to be next to oxygen in the order of importance in the sustenance of life. In fact, about two-thirds of human body is made of water. This colourless, odourless and tasteless liquid is essential for all forms of growth and development and is the basic need for sustaining human economic activities. Not only does water support a wide range of activities, it also plays a central symbolic role in rituals throughout the world and is considered a divine gift by many religions. It is indeed one of the earth’s most precious resources (Ayoade and Akintola, 1999; Padma and Namrata, 2009).
Availability of water in the desired quantity and quality, at the right time and place, has been the key to the survival of all civilizations. No other natural resource has had overwhelming influence on human history. As the human population increases, as people express their desire for a better living, as the economic activities continues to expand in scale, the demand for fresh resources continues to grow. Although water is a renewable resource, its availability in space (at a specific location) and time (at different periods of the year) is limited by climate, geographical and physical conditions (Chapman, 1996). Clean water is such scarce resource in the world that only a tiny fraction of the planet’s abundant water is available as fresh water. Of the total water on earth only about 97% of it is available as saltwater. More than 2% is locked up in ice cap or glaciers. Only less than 1% of the earth’s total volume of water is available as drinking water. The fresh water we use comes from two sources; surface and groundwater. Precipitation that does not soak into the ground or return to the atmosphere by evaporation or transpiration is surface water. The subsurface area where all available soil or rock is filled by water is groundwater (Padma and Namrama, 2009).
Although water is essential for human survival, many are denied access to sufficient potable drinking water supply. Globally, about 1.1billion people rely on unsafe drinking water resources from lakes, rivers and open wells. The majority of these are in Asia (20%) and sub-Sahara Africa (42%). Furthermore, 2.4 billion people lack adequate sanitation worldwide (WHO/UNICEF, 2008). Nevertheless, the key to increase human productivity and long life is good quality drinking water. The provision of good quality water is often regarded as an important means of improving health. In recent time, some parts of the world have been making encouraging progress in meeting the Millennium Development Goals (MDG) on water, but serious disparities remain. Lack of access to improved drinking water is still a serious problem in large portion of Asia and Sub-Sahara Africa (WHO/UNICEF, 2008).
Water quality assessment process is an evaluation of the physical, chemical and biological nature of a water body in relation to intended uses particularly as it affects human health (Chapman, 1996). The quality of water may be described in terms of concentration and state (dissolved or particulate) of some or all the organic and inorganic materials present in the water, together with certain physical characteristics of water. It is determined by in-situ measurements and by examination of water samples on site or in laboratory. The main elements of water quality monitoring are, therefore, on-site measurement, the collection and analysis of water samples, the study and evaluation of the analytical results, and the reporting of the findings. The results of analyses performed on a single water sample are only valid for the particular location and time at which the sample is taken (Marky and Raman, 2011).
Unsatisfactory water supply and unwholesome sanitation conditions can result in poor human health. This portends the fact that there are very strong relationship between water and health (WHO/UNICEF, 2004). It is a natural resource whose scarcity or poor quality can cause a chain of unpleasant situations for mankind, especially in developing countries like Nigeria where access to improved drinking water is still a serious problem. There are many ways in which poor water quality and sanitary conditions can give rise to poor health (McJunkin, 1982; WHO, 2008). Water-related diseases are responsible for 80% of all illness/deaths in developing countries, killing more than 5 million people every year (UNESCO, 2007). Water borne diseases, as well as water related diseases which include cholera and other diarrheal diseases, as well as other water related parasitic diseases like schistosmiasis, guinea worm and river blindness are very common (WHO, 2006). In developing countries, thousands of children under the age of five die every day due to drinking of contaminated water (WHO, 2006). Thus lack of safe drinking water supply, basic sanitation and hygienic practice are associated with high morbidity and mortality. In fact, one of the goals of the United Nations Millennium Development Goals (MDG) is to reduce persistent poverty and promote sustainable development worldwide especially in developing countries through the improvement of drinking water supply and sanitation. The MDG target for water is to half, by 2015, the proportion of people without sustainable access to safe drinking water and basic sanitation (UNESCO, 2007). The WHO (2008) estimates that if these improvements were to be achieved in Sub-Sahara Africa alone, 434,000 child deaths due to diarrhoea alone would be averted annually.
Groundwater exploitation has been with man way back in the ancient times. The civilizations of the ancient time had its success anchored on water supplies from groundwater as well as surface water. It is reported that in 1183 BC, crusade prisoners in Egypt constructed wells from excavated rocks which they called Joseph’s well to ensure the citadels and water supply. The drilling instead of the usual digging of wells began in the 12th century with successful drilling of well at Artois of France in 1226 (Osiakwan, 2002).
In the basement rocks, groundwater occurs in the weathered regolith and the fractured zones which sieves as the aquifer zone and usually occurs at depth ranging from 0m to a maximum of 60m. This underground water is protected from surface contamination by a layer of clay and fine grained sediments. The level of groundwater in the borehole may undergo change due to the recharge and discharge. The rate at which a borehole is recharged may vary due to variation in rainfall events, or as influent flows from nearby streams and rivers. A geological material that stores and transmits groundwater freely is known as an aquifer (Back et al., 1993).
1.2Statement of Problem
The major source of drinking water for the inhabitants of Ilorin metropolis in recent time is the untreated groundwater obtained from boreholes that are drilled across the entire study area mostly by government agencies and individuals. Most of these boreholes are newly constructed and there is no existing information on their water quality. Meanwhile, the area is known for its intensive agricultural activities and most of these boreholes are located within the vicinities of farm lands and therefore could be contaminated. Also, the area is characterized by massive underlying rocks which could contain minerals capable of impacting on the groundwater.
Although some of these pollutants are essential, others are toxic to animals, man and plants. When these pollutants accumulate beyond the recognized and recommended limits, they become toxic to living organism (man, animals and plants) (Borne, 1978). The consumption or use of water from polluted water sources is capable of causing water or chemical related diseases
1.2 Aim and Objectives of the Study
The aim of this study was to access the quality of borehole water sourced from selected boreholes in Ilorin Municipal. To achieve this aim, the objectives were as follows:
- To determine the level of heavy metals in borehole water which include: zinc (Zn), copper (Cu), iron (Fe), cadmium (Cd), lead (Pb) and manganese (Mn).
ii.To determine the physicochemical properties of the underground water (borehole) which include: temperature, turbidity, total dissolved solid, electrical conductivity, pH, phosphates, sulphates, nitrates, total hardness, chlorides and fluorides.
iii.To compare the level of heavy metal and physicochemical parameters obtained from the analysis with the WHO, NSDW and USEPA standards for drinking water to ascertain the suitability of the water for drinking purposes.
1.3 Research Questions
- What is the level of heavy metals in boreholes water in Ilorin Municpal?
- What is the physiochemical; properties of the underground water(borehole)?
- What is the comparism between level of heavy metal and physiochemical parameters obtained from the analysis with WHO,NSDW and USEPA standards for drinking water?.
1.4 Significance of the Study
According to Vanguard(2010) boreholes and hand pumps provide up to 69.6% of the potable water in Nigeria, with surface water providing 22.5% of the water needs of the communities, other water sources like rain and external supplies like tankers and piped water contribute about 8.9%. The population in Ilorin metropolis cannot be sustained without reliable access to safe water and adequate quantity. The high birth rate has led to increased reliance on borehole water. Many consumers rejected borehole water in specific seasons especially during the wet season, citing sudden change in water taste, appearance or odor, hence the need to determine quality in the dry and wet seasons. Wet Season analysis was done from Mid-June to July 2011 and Dry Season from February to Mid-March 2012.
This research will contribute to MDG 7c by determining water quality parameters and recommending for suitable action or creating awareness about water quality and water borne diseases. This research will also identify areas of water stress where less water is available for use, affecting the per capita consumption. The information from this research will be used to guide government agencies, researchers and other development organizations like NGO’s to develop strategies, policies
and institutional infrastructures to provide quality and accessible water resources to communities.
1.5 Scope of the Study
The study will be aimed at finding the physiochemical properties of borehole water in Ilorin municipal. Selected borehole sample will be used for the study analysis to check for both the present of heavy metals and physiochemical properties of borehole.