Why Namibia should focus on desalination rather than piping water from the Kavango River

NamWater's plan to pipe water from the Kavango River near Rundu to supplement Windhoek's water supplies is short-sighted, environmentally damaging, and sets Namibia up for conflict with Botswana. Our alternative vision for a desalination plant and pipeline from the coast of Namibia to Gaborone via Windhoek will promote cooperation between the two countries and meet both water and energy needs.

Uncertainty surrounding use of the Kavango River

The people living along the Kavango River in Namibia (also known as the Cubango in Angola or Okavango in Botswana) are sceptical of the government's proposal to use their most precious natural resource for people living hundreds of kilometres away in Windhoek. The traditional authorities in the area rightly say that they are concerned for the future – this river provides fish, irrigation for crops, and many other goods and services, besides its important cultural value.

At a minimum, these communities are asking for improved local water supply that would allow them to use tap water at home rather than risking crocodiles in the river each day. Angolans living on the north bank of the river are also concerned about Namibia pumping water which they rightfully share.

Beyond Namibia, the Kavango River feeds the world-famous Okavango Delta, which is Botswana's premier tourist attraction. With the decline in diamond sales and other economic sectors, Botswana is becoming increasingly reliant on tourism. On the environmental front, this Ramsar wetland and UNESCO World Heritage Site provides habitat for vast numbers of animals, including the world's largest population of African savannah elephants.

Botswana and Namibia are the top two rated countries in the world in terms of megafauna (large animals) conservation, which underpins their tourism appeal. We must keep it this way. Anything that impacts the Okavango Delta will impact Botswana's globally recognised wildlife status and the regional status of the Kavango-Zambezi Transfrontier Conservation Area. Tourism in Namibia, Botswana, and their neighbouring countries will suffer as a result.

The Kavango River is already under pressure from large green schemes and hundreds of other small and medium scale farms that use water from this river for free, as though it is an unlimited supply. No measures are being taken to limit or monitor water use, as detailed in this article and its associated report. The cumulative use of water for these schemes and many smaller farms is therefore unknown.

Without proper monitoring of current water use, we do not know what the impact of adding yet another large pipeline will have on this river. Each time another pipeline is added to the river, it invites more pipes and pumps. If Namibia is taking so much water, why shouldn't Angola take just as much? Angola plans to redirect water from their part of the river to dams further west in the Cuvelai Basin, and Namibia's pipeline will only encourage such plans. This race to the bottom of the riverbed will leave the local people on both sides with nothing, the Delta dry, and Botswana and Namibia's tourism revenue badly reduced.

Angola is developing quickly, and this includes many water-hungry developments along the Kavango River and within its wider catchment area. During the drought of 2022, the Kunene River virtually dried up, a situation exacerbated by upstream use in Angola. This could be a taste of the future for the Kavango River.

Using combined climate change models with expected agricultural expansion, scientists from Namibia and Germany predicted that the river flow may decrease by up to 60% by 2100 in a study published this year. Under such conditions, the river is expected to dry up almost completely during dry seasons and drought periods. recently decried the lack of transboundary water cooperation, citing peace, stability and prosperity as key reasons for better water management. This is a direct contradiction to Namibia's plans to pump water from the Kavango River.

During a severe region-wide drought, it is likely that Windhoek will be water stressed at the same time that the Kavango River is receiving reduced inflows from Angola. In such a time of severe water stress, how will increased water use by Namibia and Angola be viewed by Botswana, as they watch their prime tourist attraction and economic pillar start to shrink?

Rather than viewing the Kavango water as an unlimited ‘free' resource that Namibia should grab before it leaves the country, we must recognise the potential national, regional and international costs of overusing it. This is in line with a recent statement made by Penda Naanda, Namibia's Permanent Representative to the United Nations, regarding transboundary water management. Any other alternatives for securing Windhoek's water supply should be taken seriously and implemented long before the Kavango River is considered as an option.

What the Windhoek supply plan entails

The project proposed by NamWater will cost an estimated N$ 7 billion to implement. This includes laying a new pipeline from Rundu (before the Cuito River joins the Kavango) to an existing canal that links Grootfontein to the Omatako Dam. This canal, commissioned in 1987, was initially designed as part of a larger project called the Eastern National Water Carrier. The Carrier was part of a larger 1974 “Water Master Plan” that included channelling water from the Kavango River to Windhoek.

The canal part of the Carrier originally linked the Berg Aukas Mine near Grootfontein to the Omatako Dam. The mine was located on an underground aquifer, which meant that groundwater had to be continuously pumped out of the mining shafts. The 300 km-long Omatako Canal allowed this excess water to be channelled to Omatako Dam. Pipelines were built to link Omatako to Von Bach Dam near Okahandja, and from there to Windhoek. The only part of the Carrier that was never completed was a pipeline from the Kavango River to the start of the Omatako Canal. This pipeline is what the government is now proposing to build.

Taking up the pipeline project again in 2026 ignores the changes that have occurred during the 52 years since the original plan was drawn up. Due to population growth in Windhoek, the current size of the proposed pipeline is three times larger than the one initially planned. The populations in Angola and along the Kunene have increased, while several water-hungry developments have grown around the river. The threat of climate change is now better understood, along with the potential consequences for the Okavango Delta and Botswana.

On the positive side, desalination technology has improved and other water sources for Windhoek have been identified (e.g., the aquifers around the city). An honest re-assessment of the 1974 Master Plan shows that the Kavango pipeline is no longer a good option to pursue.

One important challenge associated with the project is the need to rehabilitate the Omatako Canal. The canal has fallen into disuse since the mine was closed and remains dry for most of the year (only channelling rainwater during the wet season). The Omatako Dam is thus also dry for most of the year. The canal has several cracks that will need to be fixed to prevent seepage, and unless it is covered, much of the water that it carries will be lost to evaporation.

The open canal has resulted in the deaths of millions of animals (especially reptiles, but also antelope like kudu) since its construction. Many have called for it to be covered since it was built, but these calls have gone unheeded. For the sake of the environment, this canal should either by covered with concrete slabs, or filled in with earth and abandoned permanently. Learning from this lesson, Namibia should only develop closed pipelines rather than open canals.

Desalination – a better alternative

The unregulated, increasing water use in Namibia and Angola, the threat of climate change, and the leaky open-air canal means the Eastern National Water Carrier will be an unreliable source of water for Windhoek. It could also lead to conflict and deteriorating diplomatic conditions with our neighbouring countries, particularly Botswana. Furthermore, the N$ 7 billion required for this project will be funded almost entirely by the Namibian taxpayer.

Another option that is already working in Namibia and could be considerably expanded is desalination. Unlike the Kavango River, the Atlantic Ocean has no risk of running dry. A large desalination plant or series of modular plants would not only supply Windhoek with water – it could be piped all the way to Gaborone in Botswana.

Both Namibia and Botswana are in desperate need of reliable sources of water, given the scarcity of fresh surface water in both countries and the risk of overusing underground sources. Rather than fighting for the small amount of freshwater available, the two nations should work together to develop a joint desalination plant and transboundary pipeline that could grow to supply fresh water to both countries forever. Desalination of marine water is perhaps the only source of water where supply is not capped and no ecological damage occurs if abstraction is well planned and managed.

The greatest challenge for this project is piping water from the coast to Windhoek – an elevation difference of about 1,700 metres. A large solar farm on the edge of the Namib Desert could provide the energy required to run the desalination plant(s) and pump water from an appropriate site on the central Namib coast up to Windhoek. Solar energy would be available during daylight hours for nearly 365 days of the year, shutting off only at night. This system would require one-way valves installed along the pipeline to ensure that water does not flow backwards at night.

Once the water reaches Windhoek – where it will be used mainly to recharge our aquifers (an option that prevents evaporation) – it can be mainly gravity-fed all the way to Gaborone, which is 700 metres lower than Windhoek. Along the pipeline in both countries, some water could be diverted to tanks or small dams that feed agricultural projects. High value crops grown in greenhouses using water-efficient farming methods would provide a healthy return on investment and create jobs.

This ambitious project could cost about N$ 11-13 billion, which is more than the Kavango pipeline project, but the cost need not be borne only by Namibian taxpayers. Both Namibia and Botswana would invest in the joint project and attract money from external sources.

Since this is a climate-resilient and environmentally friendly approach to meeting our water needs, it would attract international partners and private sector investment to provide startup capital. This large-scale project falls within the remit of the Green Climate Fund, an international funding agency designed to assist developing countries to mitigate and adapt to climate change.

With the right institutional arrangements, the project should be opened for public-private partnership, such that private sector capital and management expertise is harnessed. The governments would create the enabling regulatory framework to encourage investment and set pricing caps where appropriate. Additional value addition, such as high value agriculture, urban development and services, would be developed and driven by the private sector under this enabling environment, funding further water supply.

These multiple streams of investment would maximise the economic opportunities created by the pipeline and create numerous jobs for people in both countries. It would also significantly reduce the financial burden on the taxpayers in both Namibia and Botswana – ultimately costing Namibians far less than the Kavango pipeline project.

A further critical consideration is the long-term outlook for the two options. A multi-billion-dollar investment must provide enough water to meet long-term demand – accounting for population growth, development and climate change. Within only 20 to 30 years after completing the Kavango link, there may not be enough water in the Kavango to provide for the growth in demand in the central regions of Namibia, while relations with Botswana may have seriously deteriorated. At that point, a new development – a desalination option – will be needed. By contrast, desalination plants and solar energy sources can easily be scaled to meet demand, with no impact on the ocean's water supply.

Final thought – going nuclear

A Namibia-Botswana pipeline would provide another opportunity for bilateral cooperation – this time in the energy sector. Once the pipeline is established and functional, the governments could invest in a small nuclear power plant (footprint of around 20 hectares) to add to the solar plant, providing 24-hour energy for both desalination and pumping, plus considerable surplus energy for both countries. This carbon-neutral power plant would be cooled using the desalinated water. The use of nuclear power to pump at night and during the few cloudy days in the Namib would more than double the capacity of the pipeline.

A nuclear power plant could provide for the energy needs of both countries and allow them to export energy to their southern African neighbours. Nuclear power is much cleaner energy than coal, which will again attract international donors and public-private partnerships to make the dream a reality without over-burdening taxpayers. The secure baseload of nuclear energy would help ensure the stability of national electrical grids in both Namibia and Botswana, allowing further expansion of renewable solar energy.

As Namibia considers its options for meeting its long-term water and energy needs, we encourage bold new thinking. Rather than going back to a 1974 “Master Plan” for water and revamping a canal that is damaging our environment, decision makers should pursue a new vision for the future.

This vision includes a reliable water supply for the central and coastal areas of Namibia, a productive partnership with Botswana, and an option for meeting and exceeding our energy needs. Other positive spin-offs include small-scale, high-value agricultural projects to create jobs along the length of the pipeline and the upliftment of adjacent settlements, services and economic opportunities. This plan is far superior to a short-sighted pipeline that will create unnecessary tension with our neighbours and come at great cost to the people and wildlife that rely on the Kavango River.