Abstract:
Variations in river water volumes have direct or indirect effects on biodiversity
because sustainable development is highly dependent on availability of adequate
water. Global records show declining water levels in most rivers. Most rivers
flowing through TharakaNithi County have recorded notable decline in water
volumes and this is a major challenge to achieving sustainable development in the
County. Knowledge about water volume variations and factors responsible for the
variations is key to effective water resource management. This study aimed at
establishing extent of water volume decline in river Mutonga, the impact of human
water abstraction and effects of climate change on the declining water volumes over
the last 30 years. The study adopted a descriptive survey research design. The study
corrected primary and secondary data from 270 households’ heads, three regional
NEMA officials and three regional water resources authority officials. Data was
analyzed using descriptive and inferential statistics. A long-term variation in the
recorded rainfall in the region in the period between 1990 and 2020 and was
associated with the decline in river volume. There was a significant relationship
between increased temperatures and river discharge amount (0.639816>0.05). The R
square value of 0.8597, shows a significant relationship between the number of
intakes constructed to abstract water and the river discharge. It is advisable for
County Governments to adapt suitable water management strategies during
implementation of development projects that are likely to affect water resources.
