Flood zones. POT Risk Areas

Areas delimited as Flood Risk Zones according to the territorial criteria set out in Annex PN 5 “Criteria relating to the Zoning of Flood Areas and Allowable Uses therein”, common to the five Territorial Planning Plans of Navarre (POT). According to the return periods and draughts can be distinguished in: — Low risk area: areas where flooding can be expected with a return period of more than 50 years and a reduced draught (less than 0.4 m). — Medium risk area: areas where flooding can be expected with a return period of less than 50 years and a reduced draught (less than 0.4 m), or with a return period exceeding 100 years and a draught exceeding 0.4 m. — High-risk area: areas where flooding can be expected with a return period of less than 100 years and draught greater than 0.4 m. In any case it shall also be considered as a high-risk area where the water speed is equal to or greater than 1 m/s. These layers come from two-dimensional flooding studies carried out by the Government of Navarre, as well as from the processing of draught rasters and speeds for the different return periods of the development studies of the National System of Cartography of Floodable Areas (SNCZI) carried out by the Ebro and Cantabrian Hydrographic Confederations (see information sources).