South Africa’s capital is sinking

Centurion is quite literally sinking, and residents are bearing the brunt. Roads are closing, homes are threatened, and community institutions like the local hospice are in crisis as sinkholes multiply.

Despite the scale of the problem, the City of Tshwane has a fraction of the funding it needs to repair the damage.

Currently, 64 active sinkholes have been logged across Tshwane. Yet, only R14.7 million has been allocated toward repairs, compared to the over R200 million needed, according to a mayoral report.

Many of these sinkholes in the City of Tshwane have remained unaddressed for years, with some dating back to 2011.

At the root of the issue is Centurion’s unique geology, coupled with aged and unmaintained infrastructure.

“Centurion is underlain by dolomitic rock, which has been weathered and eroded over time, creating an ‘extremely uneven bedrock profile’ filled with numerous cavities,” explained Professor SW Jacobsz from the Department of Civil Engineering at the University of Pretoria.

These voids, he said, are particularly vulnerable to collapse when infiltrated by leaking water from ageing infrastructure.

This is a consequence of inadequate maintenance, with around 95% of incidents caused by water pipe failures.

Older developments are more at risk because they were built before current regulations existed, using materials and methods that have not withstood the test of time.

Jacobsz explained that these aging systems are now corroding and deteriorating, leading to persistent leaks that increase the likelihood of sinkhole formation.

The City is responsible for repairs on municipal land or where municipal infrastructure is involved, while responsibility is shared on provincial or state property.

A recent mayoral committee report, shared with NewsDay, outlines Tshwane’s sinkhole response as of June 2025.

Repairs are prioritised using a risk-based system. However, “nine small-sized and low-priority sinkholes have been earmarked for repairs” this year due to the limited R14.7 million budget.

For reference, a single large sinkhole costs at least R30 million to fix.

The City said “safeguarding, site maintenance and monitoring” are ongoing, but the report ends with a warning about the growing backlog and the urgent need for more dedicated funding.

Why exacerbates the risk?

Jacobsz said these ground collapses are largely a consequence of aging infrastructure and inadequate maintenance, with leaking water pipes responsible for around 95% of incidents.

The scale of the problem is underscored by the fact that, on a countrywide metro average, 40% of potable water is lost in the distribution networks, significantly increasing the risk in these dolomite regions.

According to the report, the Mayoral Committee acknowledged that many sinkholes in Tshwane are the result of “a lack of preventative maintenance,” which itself stems from “insufficient budget.”

It was noted that some sinkholes, especially those caused by water leaks, were “preventable” but worsened by budgetary constraints.

Jacobsz noted that building regulations for sinkhole prevention have significantly improved in dolomite-prone areas like Centurion.

Older developments, built with limited understanding of these risks and ageing materials, such as water pipes that often become “eroded and they leak,” are more vulnerable to ground collapse.

By contrast, “the regulations are more stringent today,” reflecting increased awareness of the “danger of sinkholes.”

Modern standards require “articulated coupling” at pipe entry points and prohibit burying pipes to reduce corrosion.

Construction now follows higher standards, with new developments needing approval from the Council for Geoscience and the City of Tshwane, both described as very strict.

As a result, Jacobsz said, “new developments are not really the problem.”

Political backlash

Amid mounting frustration, political pressure is escalating.

The Freedom Front Plus has launched a petition to declare Region 4 a Local State of Disaster, amassing over 3,500 signatures.

Councillor Wesley Jacobs submitted an urgent motion calling for the declaration under the Disaster Management Act, to be published in the Provincial Gazette.

Declaring a Local State of Disaster would unlock funding and resources, enabling faster intervention from provincial and national government.

The motion also demands:

• A comprehensive audit of all sinkholes and their causes within 14 working days
• Emergency budget allocations for geotechnical assessments and infrastructure repairs
• Urgent talks with the Gauteng Provincial Government and National Treasury to fund long-term infrastructure replacement, especially the asbestos piping system blamed for triggering collapses
• A feasibility study to determine the cost of full-scale sinkhole remediation

“These sinkholes pose a significant risk to human life, property, and essential municipal services,” said Jacobs.

“Many residents, houses, infrastructure and services have been negatively impacted. We, the city, can thank God, that out of the 64 current sinkholes, not one was injured or worse, a loss of life.”

The Democratic Alliance (DA) is also calling for outside intervention, appealing to the Provincial Department of Cooperative Governance and Traditional Affairs (COGTA) and the National Treasury.

“The scale, complexity, and urgency of this crisis have exceeded municipal capacity and now pose a direct threat to public safety, national infrastructure, and constitutional rights,” said DA MPL and Centurion political head, Nicole van Dyk.

“We request that both Government Departments factor… the need for funding in the 2026/2027 financial year.”

Going forward

The mayor’s office said that a city-wide maintenance strategy had been approved, requiring collaboration across departments, though concern was raised about the inefficiency of the current multi-departmental approach.

The committee agreed that “the responsibility for the maintenance of sinkholes should ideally be assigned to one department.”

To address the backlog, the 2025/26 budget process will begin earlier, with maintenance funding prioritised.

With just R14.7 million allocated, the city admits this is “significantly inadequate” to clear the backlog in the medium term, while new ones continue to form, increasing the backlog.

However, Tshwane has been addressing some of the identified potholes, recently fixing a long-standing sinkhole on Amkor Road and Clifton Avenue.

Public awareness and proactive measures are paramount to mitigate any pervasive danger.

Jacobsz emphasises that “the first thing that all owners should do is check for leaking pipes. So close all the taps in your property and go and check that water meter.”

“See if it’s running. If that water meter is running, you are in danger and you should immediately contact the City.”

This simple check can be a vital early warning system for residents living in high-risk dolomite areas.

Gauteng’s COGTA and Finance departments did not respond to queries from Newsday.

Other images of sinkholes in Centurion