NRFA Peak Flow Dataset V12

We have become aware of some problems relating to the recent release of the NRFA Peak Flow Dataset V12, which fall under two categories: Catchment Area and FARL. 

1. Catchment Area: There have been some changes to the way catchment areas are calculated, relating to a new improved method used to snap locations to the digital river flow network. On the whole these changes have been negligible, or very minor and represent an improvement on where the gauging stations are located on this digital river network. However for four catchments (33023, 41014, 33052, 42010), larger changes in catchment area have been processed. The NRFA will investigate these stations to make sure that the new area released in V12 of the dataset is an improvement on what was previously held. 
2. FARL: At five stations, where data is rejected following the introduction of a reservoir in the catchment, the incorrect FARL value is included in the files – the post-reservoir FARL has been given, where it should be the pre-reservoir value. The stations affected are in the table below, and the correct FARL value is given: 

The NRFA will investigate and correct these issues over the coming days and publish a V12.1 of the NRFA Peak Flow Dataset in due course.