Water Sources (Source of Water)

Sources of Water

The nature of the water source commonly determines the planning, design, transmission and distribution works of water supply. However, if a planner wants to go into the design of any water supply then he has to know the various forms of water sources which are:

a. Surface Water:

From natural ponds and lakes of sufficient size by continuous draft. From stream with adequate flood flows by intermittent seasonal or selective draft of clean floods water, and their storage in reservoirs adjacent to the stream or otherwise readily reached from them. From streams with low dry-weather but enough annual discharge by storage of wet-weather flows in reservoir impounded by dam through stream valleys.

b. Underground Water:

is water located beneath the earth’s surface in soil pore spaces and in the fractures of rock formation. Underground water is recharged from, and eventually flows to, the surface naturally; natural discharge often occurs at springs and seeps, and can form oases or wetland. Some of the rainwater seeps through the soil on to the non-porous rocks below. This is underground water. Sometimes due to high pressure, this water sprouts out in the form of springs. It can be obtained by digging wells, sinking tube wells, e.t.c

i. Natural Springs: There are either intermittent land springs or artesian or main springs. The water they contain has the same characteristics of deep or artesian well.

ii. Wells: These are generally dug by hand and has a diameter dictated by the space required by the machine used in the shaft in order to prevent collapse of the well stones, bricks, or precast concrete rings are incorporated as lining which also serve as impermeable stratum to exclude particles of the walls into the wells and also guide against seepage. Wells may be artesian, deep or shallow.

• Artesian Well: This is a well drilled below the very first impervious stratum to a water table under intended pressure. Whenever the water is released, it has a potential of rising above the surface of the ground. This type of well seems to defy gravity because the pressure that builds up between layers of rock gets relieved when the water finds a path to the open air. In addition, the water has been naturally filtered because it passes through porous rock as it seeps into the Earth to reach the aquifer, which is the underground water source (www.wisegeek.org).

• Deep Well: This is a well drilled to the water table just below the first impervious stratum. The water will be purer than that which is obtained from shallow well because of the natural filtration which takes place during its seepage. The water may contain the temporary or permanent hardness.

• Shallow Well: This is a well drilled less deep above the impervious stratum and the water is obtained from the water table of the sub-soil. The water is usually soft and may contain some pollutants and prone to contamination.
  iii. Borehole: This is a well using large drilling rigs like that of oil rig. The drilling machine is capable of drilling deeper than 100m into the ground, and water is then extracted by means of a mono pump manually or electrically pumping machines or using a solar powered submersible pumps.

 

iv. Rain Water: Rainwater harvesting is the accumulation and deposition of rainwater for reuse on-site, rather than allowing it to run off. Rainwater can be collected from rivers or roofs, and in many places the water collected is redirected to a deep pit (well, shaft, or borehole), a reservoir with percolation, or collected from dew or fog with nets or other tools. Its uses include water for gardens, livestock, irrigation, domestic use with proper treatment, and indoor heating for houses etc. The harvested water can also be used as drinking water, longer-term storage and for other purposes such as groundwater recharge.

Water Source Protection

Water source protection can however result in economic savings as well as better quality water. Source protection is clearly an extensive service of the basic public health principle in effective water supply and distribution system in which the water provided for domestic, animal and human consumption, should be available and wholesome. Since there is no evidence to identify that all the potentially detrimental trace level of any contaminant that could possibly be in drinking water nor developing practically universal, effective purification treatment, the best solution is obviously to preserve and protect it from contaminants at the water source as much as possible. However, it is very much essential to protect watersheds or catchment areas and other source for pathogenic and chemical pollutants where possible.

There are chances that some kind of contamination can take place to which the water from the source is sustainable. Therefore, the lower the contamination, the fewer the number and kinds of contaminants or pollutants that should be removed from the water source, the effective and less complex the cost of treatment needed (HOFHES, 1986).