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Landslides could alter water cycle in Mt Elgon Region

By IW:LEARN

March 28^th, 2025

The Mt. Elgon region is endowed with numerous natural perennial watercourses whose sources can be traced back to the springs on the slopes of Mt. Elgon.

Agricultural products like coffee, bananas, Irish potatoes, onions, wheat, vegetables, fruits, nuts, and flowers, produced for both the local market and export, are also cultivated along the river banks throughout the year.

Cultivation in the dry seasons is based on base flow, which provides water for perennial rivers.

Adjacent to the Mt. Elgon Forest are smallholder farmers who predominantly practice mixed farming but depend on the forest for their livelihood. The area has recently had its first large-scale irrigated farms and greenhouses.

Although not explicitly related to groundwater, some large-scale irrigated farms and greenhouses exist.

The breathtaking landscape of Mt. Elgon, a UNESCO Biosphere Reserve, is a haven for biodiversity and a critical resource for the communities that inhabit its slopes.

However, regular landslides in the region have raised alarm bells among environmentalists and local residents alike. They threaten the ground’s capacity to absorb and retain water, an essential function for ecological balance and human survival.

For example, at the end of November 2024, a powerful landslide struck the Bulambuli district in eastern Uganda, leaving at least fifteen people dead and over a hundred missing.

Triggered by heavy rains, the landslide buried numerous homes across several villages.

Charles Odongtho, spokesman for the Office of the Prime Minister, stated that all bridges in the area had been washed away, and roads had been flooded.

A section of locals could be seen involved in voluntary search and rescue for those who were buried by the landslides. Photo: Javier Silas Omagor.

How landslides affect groundwater

According to water experts, the aftermath of a landslide can alter the topography affecting how water flows across the land.

For instance, new channels may be formed, directing water away from certain areas and preventing it from being absorbed into the ground.

Over time, these changes can lead to altered hydrological cycles in the region, which could have potential consequences for water availability and quality.

According to the Nile Basin Initiative, the landscape's inability to effectively retain water can affect agriculture, ecosystems, and the overall water supply for local communities.

Landslides can also have devastating effects on groundwater sources, as they often lead to the physical removal of soil and rock layers that protect aquifers. When a landslide occurs, it can carry away topsoil and debris, disrupting the natural filtration system that allows groundwater to recharge.

This disturbance reduces the amount of water that can infiltrate into the ground and exposes the underlying water sources to potential contamination.

As sediments and pollutants from the surface are washed into these groundwater systems, the quality of the water can be severely compromised, posing risks to health and safety for those reliant on these sources for drinking water and irrigation.

The aftermath of floods and landslides poses the risk of contaminating water sources. Photo: Emma Muchunguzi.

The causes of landslides

According to the 2023 study by the Nile Basin Initiative (NBI) on the Mt. Elgon Aquifer, landslides in the Mt. Elgon region are often triggered by heavy rainfall, deforestation, and agricultural practices destabilizing the soil.

In its other report, Technical Reports Water Management Resources—Groundwater Series 2023, the company highlights mass wasting and landslides caused by overpopulation and farming in unconsolidated volcanic areas as factors impacting the availability of groundwater.

Lately, natural disasters have been a menace in Bulambuli, a district of the Mt. Elgon Aquifer, with floods topped by landslides.

In July 2023, several sub-counties were hit hard, including Buluganya Sub County, which was the most affected; schoolchildren were killed.

Over ten people were killed, with an estimated 500 displaced by the landslides a year ago.

Buluganya incident aside on September 11, 2022, tens of hundreds were made homeless while the flooding and waterlogging killed five persons.

Bulambuli district is an area within the Mt. Elgon area where several people have died in natural disasters over the last few years.

In 2010, the Government had to relocate and resettle more than 3,000 people from the neighbouring Bududa to Kiryandongo district since landslides ravaged villages.

The Government has also relocated thousands from Bududa to Bunambutye in the neighbouring embattled Bulambuli in recent years.

The region’s unique geological composition, characterized by volcanic rock and steep slopes, makes it susceptible to erosion.

As trees are cut down for timber and land is cleared for farming, the protective vegetation that once held the soil in place is lost, leading to increased runoff and soil degradation.

“Climate change is a big problem in the Elgon sub-region, and it is having a devastating impact on all the local communities,”

Beatrice Anywar, the state Minister for Environment, says.

“Between 1989 and today, a lot of lives and property have been lost. We have learned that the ongoing cultivation on the slopes of the steeps has always triggered these effects,” notes the Minister.

She narrates that an integrated landscape management approach is being implemented in this region, and she says,

" We strongly hope that this will be vital to restoring depleted forest cover and river banks.”

Justifying her notion, the Minister said that such irresponsible human-induced activities on the environment,

"weaken the soil texture of the mountain to hold hence mudslides, landslides, and floods, which eventually disrupt the groundwater composition.”

Anywar emphasises that the government is aware that the environment underpins all human well-being, and land and environmental degradation undermine the government’s development.

Costs for water absorption

The ability of the ground to absorb and retain water is crucial for maintaining the region’s water supply.

According to Denis Ngabirano, the senior water expert at the Ministry of Water and Environment, healthy soil acts like a sponge, soaking up rainwater and slowly releasing it into rivers and streams.

“However, landslides disrupt this natural process,” Ngabirano explained.

“When soil is displaced, the ground becomes compacted and less permeable, reducing its capacity to absorb water”

The water expert continued:

“This not only leads to increased surface runoff but also exacerbates the risk of flooding in low-lying areas.”

The consequence is obvious: These interruptions result in the region not having good groundwater potential for boreholes, shallow wells, and springs.

It goes without saying that this also affects surface water sources, such as water pans, shades, dams, rivers, and streams.

The aquifer system has several dams, springs, streams, rivers, and shallow wells, but the locals bear the brunt whenever natural disasters such as landslides strike.

A young man takes a lonely but frightening walk past their family’s destroyed house in the landslide that hit Bulunganya village. Photo: Javier Silas Omagor.

Impact on local communities

For the communities living around Mt. Elgon, the consequences of reduced water absorption are dire.

Many rely on rain-fed agriculture for their livelihoods, and diminished soil health directly impacts crop yields.

As water becomes scarcer, the competition for this vital resource intensifies, leading to conflicts among farmers and threatening food security.

Moreover, the loss of water retention capacity can lead to a vicious cycle of environmental degradation.

“The situation (landslides) leave a big negative on our shallow wells and springs seasonally, and that affects our lives and agricultural production as well,”

Silver Mungoma, a farmer in Wanale sub-county, Mbale district, said.

Mungoma stressed that “with less water available, vegetation struggles to thrive, further destabilizing the soil and increasing the likelihood of future landslides.”

This cycle affects agriculture and threatens the delicate ecosystems that depend on consistent water flow.

Annet Nandutu, a local resident, says that groundwater depletion directly threatens her community’s food security and livelihoods.

“I want to urge the government to find sustainable solutions to this problem,”

she calls out.

Women stranded in the mudslides buried village of Namisuni as they struggle to find a way out of danger. Photo: Zewu Kanyago.

Indigenous knowledge and sustainable practices

In response to these challenges, local communities are turning to traditional practices that have long been used to manage water resources sustainably.

The Wells of Wisdom initiative, which emphasizes the importance of indigenous knowledge in groundwater conservation, is gaining traction.

Beatrice Nambale, a 34-year-old resident, says that they are involved in tree growing to combat landslides, which have become more frequent in the region.

“The idea is to try as much as possible to plant these trees that experts advise us to grow so that we can keep our soil strong enough to hold,”

Nambale said.

Elders in the community are sharing techniques for soil conservation, such as contour farming and agroforestry, which help stabilize the soil and enhance its water retention capabilities.

Collaboration with external organizations has also led to innovative solutions that blend traditional practices.

Fortunately, the development of the Mount Elgon model by NBI under its Mount Elgon Transboundary Aquifer Diagnostic Analysis and Ground Water Modelling, Outcomes, and Steps Forward could help improve knowledge of the aquifer and predict the future status of groundwater in this region.

Through further improvements, starting with the inclusion of monitoring data, the Mount Elgon groundwater model can become a standard tool for managing water resources in the region, including conjunctive use and possible transboundary impact.

About the project

The Nile Basin Initiative (NBI) is implementing a Project entitled “Enhancing Conjunctive Management of Surface and Groundwater Resources in Selected Transboundary Aquifers: Case Study for Selected Shared Groundwater Bodies in the Nile Basin,” with funding from the Global Environment Facility (GEF) through the United Nations Development Programme (UNDP). The goal is to improve water resource management at the national and basin levels.

The first phase concentrated on building knowledge and capacity for the sustainable use and management of significant transboundary aquifers within the Nile Basin. Three aquifer areas were selected for intervention: the Kagera aquifer, shared by Uganda, Tanzania, Rwanda, and Burundi; the Mt. Elgon aquifer, shared by Uganda and Kenya; and the Gedaref-Adigrat aquifer, shared by Sudan and Ethiopia. The Mount Elgon aquifer, in particular, faces significant water stress due to a lack of water storage and seasonal river flow variability. Relying heavily on groundwater, which is being depleted by population growth and increased tube well use, the aquifer shows a decline in water levels. As a result, the government and households face the cost of deepening or digging new wells and lowering pumps.

The initial phase involved gathering existing data and creating a Shared Aquifer Diagnostic Report (SADA) for the three selected aquifers. The subsequent phase engaged in groundwater modeling to enhance the understanding of the aquifers and analyze scenarios based on changes in climate and groundwater use. Managed Aquifer Recharge (MAR) techniques are being explored to help replenish groundwater levels, ensuring a more stable and secure water supply in areas like Mount Elgon, where demand is increasing.

For more information on the project, please contact the Project Manager, Maha Abdelraheem Ismail (mabdelraheem@nilebasin.org), visit the project website, or view the dedicated project page on iwlearn.net.