The causes of flooding in Aberdare, Aberaman, Rhydyfelin and Hawthorn during Storm Dennis in 2020 have been revealed. Two more section 19 reports have been published by Rhondda Cynon Taf Council, one covering Aberdare and Aberaman and the other covering Rhydyfelin and Hawthorn, looking into the floods of February two years ago.
The Aberdare and Aberaman report said there was internal flooding to 45 homes, five commercial premises and that there was flooding to the highway. The report said the main source of flooding in the area was from the significant overland run-off generated from the steep hillsides above Aberdare and Aberaman North draining to lower ground through a series of ordinary watercourses, many of which became overwhelmed with water and debris and eventually overflowed.
After reviewing the condition and hydraulic performance of the culvert infrastructures which were the sources of flooding to properties, two culvert networks were judged to have provided inadequate standards of protection in with free flowing and blocked water. The other culvert network identified as a source of flooding was judged to have adequate standards of protection in free flowing water.
