properties affected
homes displaced
of water in some homes
On 30 July 2026, a sudden flood from historic mine workings devastated homes in Gwaelod-y-Garth following a planned blast at Taffs Well Quarry.
Homes were flooded, roads and fields were covered in mud and debris, and thirteen households were forced to leave their homes. Residents in surrounding communities also reported tremors around the time of the incident, including in Pentyrch, Radyr and Taffs Well.
The historic Garth Iron Mine lies within approximately two miles of an estimated 8,000–12,000 homes across Gwaelod-y-Garth, Taffs Well, Pentyrch, Morganstown, Radyr and neighbouring communities. What happened therefore raises important questions not only for those directly affected by the flooding, but for the wider area.
Stronger Together brings residents together to understand what happened, seek answers and accountability, support those affected, and help ensure our communities are protected from anything like this happening again.
What we know
On 5 August 2026 the Health and Safety Executive set out what its investigation had found.
A substantial quantity of rock from a planned blast entered one of four interconnected known bodies of water collected in the old iron mine workings. A substantial volume of that water was displaced out of an existing mine adit.
Health and Safety Executive, 5 August 2026
The HSE has also said that the information used in the blast design is the focus of its continuing investigation. That investigation has not yet reported.
We now know the immediate cause of the flood. What remains unanswered is why this risk was not prevented, whether the danger to homes below the hill had been properly assessed, and what will now be done to protect residents from it happening again.
Were you affected?
Register your damage, tell us what you saw, and hear about meetings and developments.
Understand what happened
The events of 30 July, the hill above the village, and the questions still open.
For Councillors and journalists
What residents are asking for, and how to reach the committee.
Were you affected by the flooding?
The more of us the group hears from, the clearer the picture becomes and the harder our questions are to set aside.