Water and energy supplies remain critical restrictions to sustainable development. Existing water scarcity is being aggravated by the signs of climate change, namely, reduced rainfall in some areas, while in others an increase in temperatures. Climate change in Namibia has the potential to undermine natural resource-based sectors including agriculture, fisheries and the blossoming nature-based tourism sector. The increased incidents of drought and flood events will ensure continued adversity for the poorest segments of society – rural subsistence farmers – who are also challenged by land degradation.
Current status
Climatic variability is a common phenomenon in Namibia, where persistent droughts, unpredictable and variable rainfall and temperatures have become a norm. About 70% of Namibia’s population depend directly on subsistence agriculture (crop and livestock rearing), forestry, nature tourism, indigenous biodiversity and fisheries, which form the basis and backbone of the country’s economy. These resources are vulnerable and sensitive to the anthropogenic climate change, which is predicted to raise global air temperature by between roughly 2 and 5 °C, and alter regional rainfall patterns by the end of this century.
It has been predicted with a high degree of certainty that Namibia will become hotter throughout the years (with a predicted increase in temperatures of between 1°C and 3,5°C in summer and 1°C to 4°C in winter in the period 2046 – 2065). This implies that higher water temperatures and changes in extremes, including floods and droughts, are projected to affect water quality and exacerbate many forms of water pollution.
The government of the Republic of Namibia has identified seven sectors, namely, water resources, marine resources, agriculture, biodiversity ecosystems (tourism), coastal zones, health and energy to be vulnerable to climate change. It has been stated that even if rainfall changes little from present levels, the water balance is anticipated to become drier due to increase in evaporation rates as a result of increases in temperature. Under such scenario of decreases in rainfall and increase in evaporation, Namibia is likely to face severe water shortages.
Climate change is likely to affect water resources by increasing the demand for water, changing surface water and stream flow regimes and through possible effects on groundwater, such as depth to the water table and water quality. Based on the projections, water sources and supply in Africa are already threatened by unsustainable use. Climate change could add another strain on the already existing water scarcity.
Global warming is predicted to reduce soil moisture in sub-humid zones and reduce runoff. Namibia’s aridity is expected to increase grazing stress, deteriorate vegetation resulting in reduction of livestock productivity due to heat stress, reduction of crop yields, resulting in temporary or even longer-term food shortages, poor nutrition, malnutrition and dependency on others, increase pressure on water resources and reduce arable land as the climate is likely to become hotter and drier, presenting a challenge for combating desertification and land degradation.
Provision of basic services to rural communities
The low population density and vast area of Namibia makes it difficult to provide rural areas with access to basic services such as clean water, electricity and sanitation. While good improvements have been made in the area of water supply, providing access to sanitation and electricity is a key impediment to rural development.
Shortcomings in the supply of basic sanitation have far-reaching consequences for the health status of the population. Drinking water is often contaminated due to poor sanitation, which causes problems such as diarrhoea, polio and cholera among young children. Improved sanitation facilities are needed as a fundamental pillar for the health of the rural population. The effort by MLRGH to provide toilets in rural areas is appreciated and we call upon the government through the line ministry to continue with this program.
Impoundments
The demand for readily available surface water in semi-arid and arid areas has led to the construction of some large and many small impoundments on ephemeral river systems. A number of earth dams were dug in some parts of the country, especially in the central northern regions, to provide water for livestock. In some areas people use water for drinking and other household activities due to the unavailability of potable water.
Pollution control of surface water
A water reservoir on an ephemeral river is at risk from at least three sources of pollution. Permanent surface water is at greater risk of direct pollution from the immediate surroundings (shores, air, and acid rain) than the remainder of an ephemeral river, which has a layer of unsaturated soil to filter out some pollutants. Ephemeral floods naturally transport significant quantities of organic material and sediments, which accumulate in dry riverbeds during the dry season. Accumulation of organic materials in impoundments can lead to increased nutrient levels and ultimately result in eutrophication. Decay of organic matter can cause temporary anoxic conditions in lower stratification layers of the water body, which affects aquatic life and requires constant adjustment of water abstraction depth for human consumption. This can be observed sporadically in Lake Oponono. High evaporation rates in arid areas also increase concentration of organic and inorganic compounds in dam water over time.
• Sioni Ikela is the SPYL’s secretary of health, population and environment.