Water Supply in Lesotho

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					                   WATER RESOURCES IN LESOTHO
INTRODUCTION
Water resources are sources of water that are useful to human, plants and animals.
They can be used agriculturally, industrially, for domestic purposes, recreationally and
for environmental activities. These resources have to be well managed to avoid their
scarcity in the future because they play a vital role in the environment.

Water resources are divisible into two categories mainly:

      Surface water resources
      Underground water resources

Each of these categories is part of the earth's water circulatory system called the
hydrological circle and ultimately derived from precipitation which is rainfall and snow.
The loss of the other is the gain of the other e.g. water on the surface may be lost by
seeping into ground and therefore the ground would be gaining that percentage of
water.



                        SURFACE WATER RESOURCES
They found in:

      Rivers
      Dams

Rivers

As precipitation takes place, some of the water infiltrates into the ground and percolates
to water-table. Due to the steep ground, the water may flow from the high head to the
lower head of the water-table. Eventually the volume of water at this area increases and
spring out to ground surface because of high pressure generated, forming a channel of
water. Due to erosion, this will finally form what is called a river. This mostly happens in
the highlands because of their high relief hence why rivers in Lesotho flow from the
highlands to the lowlands.

Mohokare, Senqu and Makhaleng are examples of rivers that flow from the highlands to
lowlands of Lesotho. Wetlands are form of tributaries of rivers in highlands hence why
the river flow in the highlands is higher than one in the lowlands. River flow in the
highlands is also high because of the high relief.
Dams

In Lesotho, dams are forms of reservoirs constructed to conserve water. It is formed
from the collection of water from a number of different sources e.g. Katse dam uses
water from Bokong and Malibamats'o rivers. They also consume water from
precipitation that falls directly on the surface of a dam and from the inflow of water from
surface run-offs.



                         GROUNDWATER RESOURCES
As water soaks into the ground, a percentage of it adheres to clay and sand to provide
water to plants through their roots. This water is said to be in the unsaturated or vadose
zone, most of vadose zones are covered with air rather than water hence why they are
unsaturated. Then gravity continues to pull down the other percentage down through
the ground. Finally, the water will reach the saturated area where all the pores are filled
with water. These saturated and unsaturated zones are separated by what is called a
water-table.

The water at this area is held by a rock called an aquifer. All these constitute what is
called ground water resources.

The water at this area can be obtained through the following:

   a) Wells− they occur when the water-table reaches the surface of the earth. They
      usually form naturally due to high rainfall that intent to increase the level of water-
      table.
   b) Springs− they also naturally occur when the water-table reaches the surface of
      the earth, but they usually form as flow of water from cracks of rocks.
   c) Hand pumps− they are formed by drilling a deep hole into the ground until a
      saturated zone is reached. The water is then obtained using a pump.



These groundwater resources have played a crucial role in water supply for both rural
villages and urban centers in Lesotho. Use of developed and undeveloped springs as
well as hand pump and high capacity boreholes are all contingent upon groundwater
supplies. And Lesotho's long dry season and recurrent droughts, coupled with
significant soil erosion and siltation of streams, use of groundwater reservoir provide an
effective method of water supply.
    FACTORS AFFECTING WATER RESOURCES IN LESOTHO


1. CLIMATIC CONDITIONS

          Rainfall − As rain falls into the ground, some of the water will infiltrate and
           percolate down the water table hence increasing the water table level.
           This increases the amount of water to be obtained. Also, some of water
           may not infiltrate due fully recharged soil so it will run-off the surface of the
           earth, filling up rivers and dams.

          Snow − As snow melts, some of it will contribute to surface run-off and
           therefore increasing the amount of surface water. Some of the snow will
           infiltrate into the ground and therefore increasing the volume of water
           available in the ground.

          Temperature − temperature is one of the common factors encountered in
           Lesotho. As temperatures are high, there too much evaporation from the
           surface water resources therefore decreasing the water available.

2. PHYSICAL FACTORS

        Land use

                 Construction of buildings and roads across wetlands reduce a
                  number of wetlands which keep rivers flowing.
                 Live overgrazing and tamping on the wetlands.
                 Overexploitation of wetlands.

3. GEOLOGICAL FACTORS

If the base of an aquifer is permeable or cracked, some of the water would be lost as
it will penetrate through it. This would result in the shortage of water for the users. If
the ground level is mainly composed of an impermeable rock, Most of the water
would run off and therefore increasing the volume of water available on surface of
the earth. While the underground water would be available in small volumes.
 ADVANTAGES AND DISADVANTAGES OF WATER RESOURCES


Disadvantages

      Groundwater resources

                    The moisture from the ground may be in contact with the
                     foundation components and cause the engineering structure
                     to collapse.

                    If the volume of water available in the ground reduces,
                     people using this water would not get enough water to
                     satisfy their needs.

                    If the water table happens to reach the surface of the earth
                     on a farm area, it may disturb the soil structure of that area,
                     resulting in the low chances of consuming good crops.


      Surface water resource

                    If the water from the surface is used without treatment, it
                     may cause illness to the users as it is exposed to the
                     surrounding. It may be contaminated by pollution from the
                     industries e.g. industries produce gases that may cause acid
                     rain that will in turn contaminate water resources.

                    During construction of Katse dam:
                        i. Wild plants and animals were misplaced.
                       ii. Arable land was destroyed.
                      iii. Lively hood of people was changed.
                      iv.  Risk of flooding was also increased.
  Advantages

         Groundwater resources

                        Water from the ground is obtained naturally filtered resulting
                         in the reduction of cost for cleaning the water and the
                         illnesses caused by contaminated water.
                        Water from the ground also helps in the formation of rivers
                         that are of beneficial to the environment e.g. for irrigation, for
                         domestic purposes.

         Surface water resources

                        They can be used for agricultural purposes e.g. irrigation
                        Fishing
                        Generation of electricity



RECOMMENDATIONS

   Unleaded petrol should be used in order to reduce harmful gases that cause acid
    rain that in turn contaminate water. Also combustion of materials that produce
    harmful gases should be ended.
   Surface water should be well conserved as reduce its scarcity in the future.
   Forest plantation should be promoted as they reduce the amount of carbon
    dioxide in the atmosphere hence decreasing the amount of acid rain.
   Building of structures over wetlands should be ended as it reduces the amount of
    available water resources.

				
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Description: Listed in the doc are the various sources of water and how they are affected by human activities.