According to United Nations report 2018, there are 2.1 billion people globally living without safe water at home and 80 percent of these people live in rural areas. Water scarcity continues to be a global challenge as the population increases coupled with erratic climate patterns leading to floods, rising sea levels, and global warming. These changes have negative impact on food security, health and general social-economic development. However, Sustainable Development Goals, particularly Goal 6 on ensuring availability and sustainable management of water and sanitation for all, provides an optimistic framework for addressing the concerns associated with water access at international level.
On her part, Africa is guided by Agenda 2063 framework that provides for equitable and sustainable use and management of water resources for the continent’s socio-economic development and regional cooperation. However, the situation of water access on the continent is still not quite impressive. At first glance, Africa appears to be endowed with abundant water resources. Africa has big rivers, large lakes, vast wetlands, and limited but widespread groundwater. Much of this is located in the Central African sub-region and in the island countries. Africa has 17No. rivers with catchment areas greater than 100,000km2; and it has more than 160No. lakes larger than 27km2, most of which are located around the equatorial region and the sub-humid East African Highlands within the Rift Valley.
Rainfall in Africa is about 670mm per year with greater variation in time and place. Temporal variability of rainfall is typically 40 percent around the mean; much higher than in temperate zones. At sub regional level, the spatial distribution of rainfall is varied. The highest rainfall occurs in the Island countries (1,700mm per year), the Central African countries (1,430mm), and the Gulf of Guinea (1,407mm). The lowest precipitation occurs in the northern countries where average annual rainfall is only 71.4mm.
In spite of the vast availability of water in Africa, supply services are highly inadequate. In rural Africa, for instance, about 65 percent of the population does not have access to adequate supply of water. In urban areas, 25 percent do not have access to adequate water.
Kenya’s water access and flooding challenges appear to mirror the bigger picture of African continent. With an estimated population of 47.6 million (KNBS, 2019), Kenya is characterized as water scarce as about 80 percent of the country is arid and semi-arid. At the same time, flooding is a frequent occurrence in the country especially during heavy rains. Rivers Nzoia, Nyando and Tana are among the rivers known for flooding catastrophes. In spite of that, the rain water that causes flooding present a huge opportunity for harvesting, storage and use in dry seasons particularly in semi-arid and arid areas of Kenya.
Owing to increasing need for water for domestic use as well as agricultural and industrial purposes to support the Government’s Big Four Agenda and to satisfy the Constitution of Kenya 2010 provision on the right to water, there is considerable pressure exerted on the country’s available water resources which take different forms. For instance, the average annual rainfall in Kenya is 630mm with a variation from less than 200mm in Northern Kenya to over 1,800mm on the slopes of Mt. Kenya. Her water endowment at 647m3/capita is below the global bench mark of 1,000m3/capita. Freshwater resources are limited and unevenly distributed in Kenya; therefore, the contribution made by dams and reservoirs to the harnessing of water resources are inevitable (Samantha Marshall, 2011).
The development of water storage includes water harvesting as outlined in the National Water Harvesting and Storage Policy 2010, which recommends water storage increase from the current 5.3m3 per capita to 16m3 per capita by 2030 taking into account, among other factors, Kenya’s population growth. This requires an increase in capacity from 124Mm3 to 4.5Bm3 over the same duration.
The current status of storage shows that nationally, there are 26No. large dams with about 3,906Mm3 of stored water for hydropower. The total capacity of the major water supply storage dams is about 95Mm3. Another 47No. relatively large non-hydroelectric dams and 3,000No. small dams together with pans had a total storage of 124Mm3 by the year 2010. This total combined is below the threshold value of 4.5Bm3 implying that there is need to increase storage (Draft National Water Strategy, 2019).
Against the stated background, the Government of Kenya is committed to ensuring that Kenyans have access to adequate water by the year 2030. Currently, the water coverage in Kenya stands at 72%.
Economic Benefits for Dams in Kenya
Economic growth and food production will be boosted through irrigation which requires investment in water storage and not dependence on rain-fed agriculture.
The following are some of the immediate economic benefits of large Dams construction in the Country:
- To harvest rainwater during the rainy seasons hence store water for use during drought while mitigating against the effects of flood control.
- To minimize the effects drought and climate change. Water storage in various water infrastructure such as dams and boreholes will provide irrigation water thereby saving the government approximately Kshs 30billion for food imports.
- To increase the coverage of water services in the country and support the efforts to achieve the MDGs.
- Provision of clean and portable water is a preventive measure in reducing the prevalence of water borne diseases in the country.
- Availability of water for livestock production in ASAL areas of the country hence, improved and sustained livelihoods.