Groundwater level and rainfall analysis

Groundwater level and rainfall analysis

Rainfall

Daily rainfall data from all local rainfall stations (Met Éireann) are used to calculate average annual rainfall within catchment.

The Standardised Precipitation Index (SPI) graphs calculated for the synoptic stations are used to describe periods of above or below average rainfall.

Daily Potential Evapotranspiration (PE) data is calculated from synoptic station(s) data within catchment.

Rainfall and PE data are used to calculate effective rainfall and an initial estimate of the range of outflow from the catchment which is compared to hydrometric data.

 

Surface water

We are using data from the OPW, the EPA, Local Authorities (LA) and ESB currently monitor surface level and/or flow (hydrometric data) at different locations within the catchments.

Flow statistics from this hydrometric data are compared to the calculated Q95s from EPA hydrometric data. The flow duration curves are used to describe how flow changes throughout the catchment.

If there are no hydrometric stations in the catchment modelled estimates of flow (Naturalised and Influenced Mean Flows and Q95s) from EPA's QUBE model is used.

 

Groundwater level

Groundwater hydrographs provide direct evidence of how aquifers are behaving.

We are using groundwater hydrographs from the EPA's national monitoring network to understand the impacts of recharge, abstraction and climate change within each catchment. 

To interpret the hydrographs, we are using calculated standardised precipitation indices and effective rainfall.