NRFA Review of the Year: 2023/2024

The UK Surface and Groundwater Archives Committee (SAGA) convened for its 41st Annual meeting held on the 6th March 2024.

The SAGA Committee comprises representatives of organisations from across the UK involved in the measurement, management or use of hydrometric data.  This year’s meeting was attended by members of the UK Centre for Ecology & Hydrology, British Geological Survey, Natural Environment Research Council, Welsh Government, Environment Agency, Scottish Environment Protection Agency, Natural Resources Wales, Met Office, Canal & River Trust, British Hydrological Society, Chartered Institution of Water and Environmental Management and representatives from the UK water industry (Thames Water).  Amongst the items discussed at this year’s meeting was a review of the activities of the National River Flow Archive (NRFA) over the last 12 months.

As custodians of the nation’s central database for hydrometric data, the NRFA’s activities have included updating and ongoing maintenance of its holdings.  Ensuring that the Archive is up to date involves an intensive programme of year-round work to quality control new data before it is added to the Archive, as well as reviewing existing data.  During 2023/2024, NRFA staff carried out a two-day visit to the Kent and South London (KSL) area with the Environment Agency.  Later in the year, NRFA staff visited Yorkshire and were hosted by Hydrometry & Telemetry and Hydrology staff from the EA’s North East of England Area.  In both cases, the visits began with an office meeting at which the Environment Agency’s flow gauging network in the area was discussed.  Updates to the supporting information were identified, resulting in improvements to the holdings of the NRFA.  The office meetings were followed by a day of visits to gauging stations in the Medway, Eden and Mole catchments for the Southern trip, and to gauging stations on rivers to the west and north-west of York for the Yorkshire visit.  The sites selected covered a range of different monitoring technologies. In 2024/2025, the NRFA are planning 2-3 liaison visits including to the Environment Agency’s Hertfordshire and North London area.  

The annual update to the Archive this year contained data for the water year 2021/2022.  The year was dry, especially in England and Wales which both saw around 80% of their average rainfall.  There were high rivers flows and flooding in February 2022 which saw three named storms (‘Dudley’, ‘Eunice’ and ‘Franklin’).  However, rainfall and river flows were below average across both the spring (March to May 2022) and summer months (June to August 2022).

Alongside the routine update to daily flow data, an annual update to peak flow data as well as a period of record review of a subset of peak flow stations led to the release of Version 12 on the 13th September 2023, which reflected the NRFA data holdings at the time.  The NRFA’s Peak Flow Dataset provides flood data for 917 river flow gauging stations across the UK and during the review we looked at over 3,500 years of station data. On the 2nd November 2023, the NRFA also released version 12.1 of the NRFA Peak Flow Dataset which included the correction to some catchment descriptors at some sites.

NRFA staff continued to liaise and engage with key stakeholders and the user community, with online and in person seminars for the British Hydrological Society, the Chartered Institution of Water and Environmental Management Water Resources Panel, the Science Media Centre and the Climate Change Commission. 

The NRFA website remains very popular and has seen further increases in the activity in 2023/2024.  There were around 28,500 total downloads across river flow, spatial and metadata.  There were around 1,055,000 page views by 123, 000 users across all pages on the NRFA website, up 43% on 2022.  The most popular page was the search page, which received nearly 74,000 views and was then followed by the home page which gained over 50,000 views.  The NRFA API has also seen sustained usage with data downloaded just over 600,000 times.
The National Hydrological Monitoring Programme (NHMP), operated jointly by the UK Centre for Ecology & Hydrology and the British Geological Survey has continued to publish the monthly Hydrological Summaries for the UK.  In the spring of 2023 the NHMP team responded to media enquiries about low flows and drought risk, in the summer on the influence of a wet July on the hydrological situation, and in January of 2024 during a notable flood event.

Isabella Tindall, Manager of the NRFA commented that “2023/2024 was a successful year for the NRFA, as both the National Groundwater Level Archive (managed by the British Geological Survey) and the NRFA celebrated their joint 40th Anniversary.  Presentations were given at both Geological Society and British Hydrological Society meetings to illustrate the change in data monitoring, analysis and access over the last four decades.  At the SAGA Committee meeting our plans for the next 12 months were discussed.  They comprise continued improvement to our data, website, and tools, including assessing the differences between the data available via the Measuring Authority APIs and the NRFA data holdings.”