The identification of historic floods and floodplains, the delineation of flood-prone areas and the assessment of potential flood impacts are the main objectives of the ongoing review and update of the preliminary flood risk assessment (PFRA) for the third planning cycle.

The work is being carried out by a consortium of the Institute of Meteorology and Water Management – NRI (leader) and the Arcadis company, with the participation of the Polish Geological Institute – NRI. Specialists from the PGI-NRI Groundwater Identification and Protection Department are once again participating in this work, carrying out tasks with regard to groundwater flooding.

Flooding is one of the most dangerous and devastating natural hazards. Prevention is the best way to avoid this type of natural disaster, which includes diagnosing and assessing the possibility of flooding. A preliminary flood risk assessment, the execution of which is an obligation under the Water Act and the EU Floods Directive, serves this purpose.

The preliminary flood risk assessment covers the whole country, including the division into river basin districts. The first preliminary flood risk assessment was published in 2011. The review and update of this document was completed in 2018, and its annex included the 'Methodology for the development of a preliminary flood risk assessment (PFRA) for groundwater floods (flooding)', carried out by PGI-NRI experts participating in the project.

In the current third planning cycle, both the review and update of the preliminary flood risk assessment will be carried out by 22 December 2024. The study is financed by the European Funds for Infrastructure, Climate, Environment (FEnIKS) 2021-2027.

PGI-NRI has for many years been involved in the identification and analysis of areas at risk of groundwater floods (flooding). The result of this work is, inter alia, the 'Map of areas in danger of being flooded in Poland', first drawn up in 2003-2006. The mapped areas show the maximum possible extent of flooding (i.e., the location of the groundwater table close to the land surface, resulting in waterlogging) in the region and vicinity of a river valley.

The study has become one of the elements of a warning system against dangerous phenomena that pose a threat to groundwater supply and abstraction zones. Areas at risk of flooding in and adjacent to river valleys were delineated using geological, hydrogeological and hydrological materials and a detailed analysis of the morphology and hydrography of the area.

Text: Anita Starzycka, Piotr Wesołowski, Anna Bagińska