4f4c4942-4343-5764-6473-313631333937 English Natural Resources Wales Maes y Ffynnon Bangor LL57 2DW Wales opendata@cyfoethnaturiolcymru.gov.uk 2026-01-23T14:34:25.221Z NRW 1.0 wel British National Grid (EPSG:27700) Wales Fluvial Flow Database (WFFD) Wales Fluvial Flow Database (WFFD) 2025-10-16 NRW_DS161397 River peak flow estimates and hydrographs used in Flood Risk Assessment Wales (FRAW, 2019) and covering watercourses with a catchment area greater than 3km2. Estimates created at regular intervals along a watercourse and stored in an ESRI Arc file geodatabase. At each interval (node) a variety of information is provided that includes: - catchment descriptors extracted from FEH. - donor observation gauges used within the flow estimation calculations. - the donor observation gauges used within the flow estimation calculations. - the time to peak and storm duration for the hydrographs and the calculated peak flows and hydrographs for each return period (both from the statistical and hybrid methodologies). - information about the quality control checks carried out on each point, a decision log outlining any changes taken on each WFFD point before use in the FRAW project, and the final modelled inflow polygons used in the FRAW fluvial hydraulic models. River peak flow estimates and hydrographs used in Flood Risk Assessment Wales (FRAW, 2019) and covering watercourses with a catchment area greater than 3km2. Estimates created at regular intervals along a watercourse and stored in an ESRI Arc file geodatabase. At each interval (node) a variety of information is provided that includes: - catchment descriptors extracted from FEH. - donor observation gauges used within the flow estimation calculations. - the donor observation gauges used within the flow estimation calculations. - the time to peak and storm duration for the hydrographs and the calculated peak flows and hydrographs for each return period (both from the statistical and hybrid methodologies). - information about the quality control checks carried out on each point, a decision log outlining any changes taken on each WFFD point before use in the FRAW project, and the final modelled inflow polygons used in the FRAW fluvial hydraulic models. Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en JBA Consultancy JBA Consulting, 1 Belle Vue Square, Broughton Road, Skipton, BD23 1FJ andrew.gubbin@jbaconsulting.com https://www.jbaconsulting.com/ Natural risk zones GEMET - INSPIRE themes, version 1.0 2008-06-01 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme river flows flood risk flood risk management NRW Thesaurus 2026-01-16 geonetwork.thesaurus.local.theme.converted_nrw-keywords NRW Conditional English inlandWaters environment Wales (WLS) -5.311 -2.647 51.384 53.427 2017-07-14 2019-10-18 Original data is stored with FRAW (2019) project deliverables. Contact National Flood Risk Analysis team for details. Copy of core deliverables can be accessed through X:\Flood Risk\Flood Risk Management\Hydrology\Wales Fluvial Flow Database WFFD 2019.lyr Simon James, Lead Specialist Advisor, Flood Risk Analysis Group Geographic Information System Unknown Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 This dataset has not been assessed for conformance to the referenced INSPIRE regulation. false The WFFD was created to provide national-scale river peak flow estimates for FRAW. It is based on data and flood estimation methodologies available in 2017. There has been no verification of the estimated peak flows against observed flows from telemetry gauges or local modelling studies. The WFFD does not provide detailed flow estimates required for local modelling studies and estimates could be refined by more detailed investigation and more recent datasets and methodologies. Existing WFFD estimates should either be reviewed to demonstrate they remain appropriate or new estimates should be created The WFFD was created to provide national-scale river peak flow estimates for FRAW. It is based on data and flood estimation methodologies available in 2017. There has been no verification of the estimated peak flows against observed flows from telemetry gauges or local modelling studies. The WFFD does not provide detailed flow estimates required for local modelling studies and estimates could be refined by more detailed investigation and more recent datasets and methodologies. Existing WFFD estimates should either be reviewed to demonstrate they remain appropriate or new estimates should be created