Abstract: The Hydrology Reference Network is a group of OPW hydrometric gauging stations that have been specially selected to provide a nationwide snapshot of the status of flood or drought events. These gauges were selected on the basis that they provide good quality estimates of fluvial high flows and have a suitable geographical spread across the country. The hydrological reference is used in two possible ways. This first is for reporting on large scale flood incidents after the fact. The second is for tracking changing water levels during a flood event for the purposes of rapid reporting. As the quality of measurements at these stations are of a sufficiently high quality, it has been possible to derive certain thresholds that describe the current or previously observed status of water levels at these sites. Current water levels at these gauges can be compared to the thresholds to describe the degree of severity of flood or drought conditions at any particular time.

Lineage: Data is pulled from the selected OPW Hydrometric Gauges hourly. It should be noted that the configuration of gauges may change over time subject to new gauges becoming available that meet the acceptance criteria for the network.