Screenshot of a UK Hydrological Summary
Hydrological Summary

Thumbnail image for UK Hydrometric Register
Hydrometric Register and Statistics

Thumbnail image for Hydrological data UK 1994 Yearbook
Hydrological Yearbook

2010-12 drought and transformation

2010-2012 Drought and Transformation

Thumbnail image for The summer 2007 floods in England & Wales
Summer floods of 2007

Long term hydrograph for the River Kennet at ThealeLong-Term Hydrographs

NRFA Gauging Stations Map 2013Maps

National River Flow Archive Publications in the Hydrological Data UK Series

This series of publications documents and interprets hydrological conditions and water resource variations throughout the UK. It embraces a number of components:

Hydrological Summaries for the UK

These monthly reports are prepared jointly by the Centre for Ecology & Hydrology and the British Geological Survey as part of the National Hydrological Monitoring Programme.

Each report includes regional rainfall data - both recent and, where significant, longer term accumulations for the major administrative divisions in the water industry. Also featured are maps and representative hydrographs of river flow and groundwater levels with supporting summary statistics and details of current stocks for a selection of major reservoirs. A commentary examines notable hydrological events and summarises both the national hydrological status and the water resources outlook. The summaries are published within ten working days of month-end.

The material is freely available via this website (see Monthly Hydrological Summary for the UK)


Hydrometric Register and Statistics

These reference volumes are indispensable handbooks for practising hydrologists and a wide community of other users of hydrometric data.

The latest edition includes maps, tables and statistics for over 1500 river basins and over 160 representative wells and boreholes throughout the UK. Its principal aims are to assist data users in the selection of monitoring sites for particular investigations, and to allow more effective interpretation of analyses based upon the raw data. Comprehensive summary statistics are given for each monitoring site together with concise gauging station and catchment descriptions for the featured flow measurement stations - particular emphasis is placed on hydrometric performance and on the net effect of artificial influences on the natural flow regime.

Past editions are less comprehensive but provide summary hydrometric statistics alongside the corresponding long term averages, or extremes, to allow annual variability in surface and groundwater resources to be considered in a suitable historical context.

  • UK Hydrometric Register (2008, £15.00 or free PDF download 7.2 MB)
  • Hydrometric Register 1996-2000 (free hard copy or PDF download 15.0 MB)
  • Hydrometric Register 1991-1995 (free hard copy or PDF download 12.0 MB)
  • Hydrometric Register 1986-1990 (out of print; free PDF download 11.6 MB)
  • Hydrometric Register 1981-1985 (out of print; free PDF download 13.4 MB)

Contact the NRFA to to acquire hard copy reports.


Hydrological Reviews and Yearbooks

From 1981 to 2010 the National Hydrological Monitoring Programme (NHMP) currently published an annual review of hydrological events and hydrological conditions within each calendar year. Based on analysis and interpretation of the data holdings of the National River Flow Archive and the National Groundwater Level Archive, these regular reports place the year in its hydrological context, focussing on rainfall, evaporation and soil moisture, river flows, and groundwater levels. Until 1995 Yearbooks were published as part of the Hydrological Data UK series, bringing together the principal datasets relating to river flows, groundwater levels and areal rainfall throughout the UK and featuring a comprehensive hydrological review of the year. Also included in the editions for 1986-95 are water quality data for a representative selection of river basins throughout Britain.

In 2011 the UK Hydrological Reviews were superseded by the quarterly UK Hydrological Bulletins.

All Yearbooks, and feature articles relating to significant hydrological events or issues within the year, as well as annual hydrological reviews from 1981 onwards, are available in electronic format from the Hydrological Review of the Year page of the National Hydrological Monitoring Programme.

Hard copies of these Yearbooks are available from the National River Flow Archive Office, though a few editions are out of print; Contact the NRFA.

UK Hydrological Bulletins

These quarterly reports, prepared initially for the British Hydrological Society's newsletter (Circulation) provide an overview for the featured period.

Occasional Reports

The National Hydrological Monitoring Programme (NHMP) produces reports, or webpages, on recent hydrological events of major significance. Some aim to comprehensively summarise the event and provide a historical record, whilst others are contemporary and often preliminary assessments of an unfolding episode, and their contents should be understood in this context. A full list of these reports is available here.


Long-Term Hydrographs

In 1990 the British Geological Survey launched a series of wallcharts depicting long term variations in groundwater levels. Copies may be obtained from the British Geological Survey - for further details visit the BGS website (external link).

Long-term hydrographs of daily or monthly flows are also available for selected gauging stations (e.g. the River Thames at Kingston with records from 1883), for details contact the NRFA.



The NRFA occasionally produces maps of the distribution of gauging stations with flow records on the national archive. Gauging stations are marked by their Station Number.

  • Gauging Stations in the United Kingdom, 2013, free hard copy or PDF download 4.1 MB)

A limited number of hard copies are available. To acquire a copy contact the NRFA.