After the floods, are Kampala’s downtown buildings still safe?

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In the aftermath of the October 30 floods that turned Kampala’s bustling downtown centres, including Pentagon City Plaza, Totala, and Freedom Centre, waterlogged, fear and frustration continue to grip traders.

As water still seeps through the basements and ground floors, many are worried about the safety of their buildings. Amid the chaos, local leaders and construction experts are stepping in to calm tempers and guide affected traders through a proper compensation process and building safety.

Vincent Nyonyintono, the LC1 defence secretary for Shawuriyako B, Kikuubo Zone, said he believes local councils must play a central role in verifying beneficiaries and in clearing out the confusion among traders seeking compensation.

However, as they work on the ongoing recovery efforts, Nyonyintono said the water is still seeping through buildings, but traders keep mopping it out.

“So, we have several engagements here. Traders are meeting to discuss the way forward, compensation, rent issues for affected traders, and the way forward regarding the floods.”

Nyonyintono, however, warned that traders need to follow the right protocol to get help.

“The Office of the President should work closely with local council leaders because we know the traders personally and can verify their lists before they go to the Kampala Minister, the Lord Mayor, and finally the President,” he said.

Compliance survey

A 2022 compliance survey by the National Building Review Board (NBRB) found that nearly 78% of buildings across the country fail to meet approved construction standards.

The findings have raised alarm among experts and the public alike, casting doubt on the safety and structural integrity of Uganda’s built environment.

Building safety

Dr Apollo Buregyeya, a lecturer at Makerere University’s Department of Civil and Environmental Engineering, said building safety is broader and not just about whether a structure stands.

“It’s about functionality, sustainability, and economy. Safety means ensuring the return on investment for the owner, the protection of life for the users, and the preservation of our environment. When a building collapses, you not only lose capital, but also inflict a wound on the environment. That’s why safety is a fundamental component of national development,” he said.

Enock Kibbamu, an architect and former chairperson of the National Building Review Board (NBRB) noted recently during a Twitter (X) spaces discussion on the safety of buildings in Uganda, that because buildings serve many functions and affect many people, there is a need for professionals.

“First, a physical planner determines land use: Residential, commercial, industrial, etc. Then, a land surveyor parcels and coordinates it. Only after that can an architect step in,” he noted.

He said the architect isn’t just drawing walls, he designs function, aesthetics and compliance. Approval ensures harmony, safety, and alignment with national standards.

According to Kibbamu, without a qualified architect, there’s no assurance of structural soundness, environmental sustainability, or functionality.

“It’s not about ego or money—it’s about safety and quality of life. Approvals verify that plans meet the Building Control Act’s requirements. Land may be yours, but the building affects public safety,” he noted.

Structural engineers' view on building safety

Buregyeya shared professional insights into whether the city’s building basements that were submerged are structurally safe and what steps should be taken next.

He explains the hidden risks but also notes that most properly designed buildings will not suddenly collapse just because their basements have been submerged for a few days.

“The real risk is deeper and more long-term. This is not just rainwater. Our city’s drains carry a mixture of storm water, sewage from on-site sanitation, oil and fuel from garages, detergents, industrial effluent, plastics, and decomposing organic waste. When this cocktail settles in the basement of a building, it brings with it salts such as chlorides and sulphates, acids from decaying waste, oils and hydrocarbons, and fine clays and silts that keep structures damp,” he said.

Although concrete can live under water for a long time, he said the problem is that contaminated water carries into the pores and cracks of the concrete and down to the steel reinforcement.

And when the basement gets flooded, he said there are three main short-term concerns. “First is lateral water pressure on basement walls. Water is heavy, one metre of water outside a wall equals about one tonne per square metre pushing sideways. If water remains outside but is pumped out quickly inside, that unbalanced pressure can overstress walls not designed for it,” he said.

Secondly, Buregyeya said, is uplift or flotation.

He said, “A basement acts like a boat. Rising groundwater tries to push the floor slab up. If the designer did not check anti-floatation properly, the slab can crack or lift, especially in areas built on former wetlands.”

Thirdly, he said, is the softening and erosion of soil. He explained that moving floodwater can wash away soil supporting foundations. As such, repeated flooding and poor drainage gradually undermine the ground carrying the building, according to Buregyeya.

He further explained, “If the structure was well designed, three days of standing water may not cause instant collapse. But where basements were poorly designed or built on marginal land, the safety margin is much smaller.”

Long-term deterioration

According to Buregyeya, the bigger danger is long-term deterioration. “Concrete protects steel reinforcement by keeping it in an alkaline environment. Chlorides and other aggressive ions in dirty floodwater break down this protective layer and start corrosion,” he said.

As steel corrodes, he noted that rust occupies more space than the original metal, creating internal pressure that leads to cracking and spalling of the concrete cover, and over time, the steel bars become thinner and weaker.

“After flooding, basements rarely dry uniformly. Some parts remain damp while others dry quickly, causing wet–dry cycles. Ironically, corrosion is often most aggressive under these conditions,” Buregyeya said.

In Kampala, where some basements flood several times a year, the pattern becomes predictable according to Buregyeya.

“Flood, pump, crack, rust, repeat. The building may stand for years, but its remaining life quietly shrinks,” he said.

Immediate action needed

Buregyeya advised that there is a need to treat flooded basements as structural incidents, not cleaning jobs.

“Pump water out in stages, not violently, to avoid large, unbalanced pressures on walls. Owners should engage competent structural engineers to inspect walls, slabs, columns, and foundation areas for new cracks, tilting, soil loss, exposed steel, or spalling concrete. And findings should be documented, and repairs done promptly,” he advised.

He said Kampala Capital City Authority (KCCA) and the National Building Review Board (NBRB) should publish a simple post-flood inspection and repair protocol that entails what to check, when to restrict use, how to pump, and minimum repair standards for affected basements.

“Kampala’s flooded basements are a warning light on the dashboard. If we respond with science, enforcement, and honest planning, we can still correct course. If we simply drain, mop, and move on, the next generation will inherit a city with buildings whose decay started quietly, in three days of dirty water we chose to ignore,” he noted.