ASSESSMENT OF THE CONTRIBUTIONS OF HYDROLOGIC CYCLE TO THE WATER QUALITY PROFILE OF OTAMIRI RIVER

1.1 INTRODUCTION
Since the beginning of concern over the possible consequences of global warming, it has been widely recognized that changes in the cycling of waters between land, sea and air could have very significant impacts across many sectors of the economy, society and the environment. The characteristics of many terrestrial ecosystems, for example are heavily influenced by water availability, in the case of aquatic ecosystems, the quantity and quality of water in rivers and aquifers is fundamental to human, aquatic life and many activities. Most obviously agriculture use, industry use, power generation, transportation and waste constraint on economic development. Consequently, there have been a great many studies into the potential effect of climatic change on hydrology (focusing of cycling of water and water quality aspects with its proper analysis and assessment).
The majority of these studies have concentrated on possible changes in the water balance for example, the quality of stream water, impacts of the changes in the gravity of water such as the reliability of a water sources (supply) or the risk of contaminated source. This study focuses on techniques adopted to determine the quality of water, by carrying out chemical text, biological text and physical text on Otammiri River to ascertain its quality and beneficial use of water.

Water And The Hydrologic Cycle
Water begins its never ceasing cycle as vapour in the atmosphere as well as the water in the lakes and oceans, provides protection against extremes of both heat and cold. Hydrologic cycle refers to the complete movement of water from the atmosphere and below the earth surface. It includes water precipitation as rain, snow, hail or dew, it journey over around and through obstacles above on and below the earths surface and its eventual evaporation and return to the atmosphere. It is the longest water purification system known to man.

Water
Water is essential for man’s existence, it is needed in large quantities and in all wholesomeness despite the requirements for potable supply, water is needed for power generation, irrigation, recreation, industrial production processes and in waste disposal. The importance of water made it possible for nature to distribute it all over the regions of the earth. The planet earth contains about 70% water in form of oceans, seas, rivers, lakes and ground water. Water provided for human consumption should receive minimum possible treatment, though the best supply is one which needs no treatment at all. Public health is vulnerable to the danger of incidence of diseases, mainly through water borne, water related and water washed diseases. These diseases include cholera, typhoid and para-typhoid fever, malaria, yellow fiver, schistosomosois and guinea worm. Consequent to the incidence of disease, water treatment processes become a preciosity that require careful while handling. For an acceptable quality of water supply the international standard for drinking water established by World Health Organization (2007) states that water intended to human consumption must be free from organisms and from concentration of chemical substances that may be hazardous to health. Supplies of drinking water should be pleasant to drinking as circumstance permit.
The quality of water must be wholesome and palatable. Wholesome water must be free from organisms, poisonous and excessive amount of mineral, turbidity taste, odour, and must be well aerated.