Formal flood investigations

As the Lead Local Flood Authority (LLFA) one of Gwynedd Council’s duties under the Flood and Water Management Act (FWMA) is to investigate flood events which occur from local sources. Local sources of flooding include surface water, ordinary watercourses (including lakes and ponds or other areas of water flowing into an ordinary watercourse) and groundwater, and where there is interaction between these sources and main rivers or the sea. 

Gwynedd Council will attempt to record the circumstances surrounding all incidents of internal flooding as well as near misses. However, in some circumstances a flood incident triggers a formal investigation in accordance with Section 19 of the FWMA. A Section 19 report is circulated to key stakeholders and is made publically available. 


Section 19 of the FWMA states:

On becoming aware of a flood in its area, a LLFA must, to the extent that it considers it necessary or appropriate, identify: 

  • which risk management authorities have relevant flood risk management functions
  • whether each of those risk management authorities has exercised, or is proposing to exercise, those functions in response to a flood event 

The FWMA does not specify that the LLFA must resolve the flooding issue. However our investigation’s findings may identify actions which could reduce the likelihood of similar events or identify measures to lessen the impacts. A key function of the reporting process is that it identifies problem areas and can therefore inform future investment programmes. 

For enquiries regarding flood incident reporting or to request a copy of a Section 19 report please contact: