UK runoff trends
Staff gauge on the River Brue at Lovington
Staff gauge at bridge over the Wellow Brook at Wellow

National Hydrological Monitoring Programme - A history of the Hydrological Yearbooks

Publication of river flow data for Great Britain started with the series of Surface Water Yearbooks. The first edition, which was published in 1938 for the water-year (October-September) 1935-36, also included selected data for the previous fifteen years; the edition for 1936-37 followed in 1939. Both these publications were prepared under the direction of the Inland Water Survey Committee. Assisted by the Scottish Office, the Committee continued to publish hydrological data after the Second World War; the Yearbook for the period 1937-45 was published as a single volume in 1952. Due to economic stringency, the Survey was suspended in 1952 for a period of two years but was then re-formed as the Surface Water Survey Centre of Great Britain. A Yearbook covering the years 1945-53 was published in 1955.

In 1964 the Survey was transferred to the Water Resources Board where it remained until the Board was disbanded in 1974. The work of collecting and publishing surface water information in England and Wales then passed to the newly created Water Data Unit of the Department of the Environment (DoE). Yearbooks were published jointly each year by these organisations and the Scottish Office for the water years 1953-54 to 1965-66; thereafter information for the five calendar years 1966 to 1970 was published in one volume in 1974. Subsequent editions were renamed `Surface Water: United Kingdom' to mark the inclusion of the first records from Northern Ireland and in recognition of the move away from single year volumes. Two volumes of Surface Water: United Kingdom, covering the years 1971-73 and 1974-76 were published jointly by the Water Data Unit, the Scottish Development Department (thence The Scottish Office Environment Department) and the Department of the Environment for Northern Ireland.

Following the transfer of the Surface Water Archive to the NERC in 1982, the final edition of Surface Water: United Kingdom, for the years 1977-80, was prepared by the Institute of Hydrology at the request of the Water Directorate of the Department of the Environment, and published in 1983. The 1981 and 1982 Yearbooks were prepared concurrently and were, in 1985, the first Yearbooks published in the Hydrological data UK series. Further Yearbooks - the editions for 1983 to 1995 - were published over the following 11 years.

Responsibility for the publication of data upon which assessments of water resources in England and Wales may be made, was transferred (under the Water Act 1989) from the Department of the Environment (thence the Department of the Environment, Transport and the Regions - DETR) to the National Rivers Authority (now the Environment Agency). Part of this responsibility continued to be discharged through the publication of the Yearbook series. Water quality data - a selection from the Harmonised Monitoring Scheme Archive - were published in each Yearbook from 1986 to 1995; responsibility for the maintenance of the Harmonised Monitoring database was transferred from the DETR to the Environment Agency in 1998.

A compilation of `Groundwater levels in England during 1963' which was produced by the Geological Survey of Great Britain (prior to its incorporation into the Institute of Geological Sciences), was the precursor to the publication of groundwater level data on a national basis. The more formal Groundwater Yearbook series was instigated by the Water Resources Board which published the inaugural edition, for 1964-66, and a further volume for 1967, both covering England and Wales. In 1975 a third Yearbook, for 1968-70, was published by the Water Data Unit. The Groundwater: United Kingdom series was introduced in 1978 with the production of the 1971-73 volume, also published by the Water Data Unit.

Following the transfer of the Groundwater Archive to the Institute of Geological Sciences (now the British Geological Survey), the second edition of Groundwater: United Kingdom, covering the period 1974-80, was prepared by the Institute of Hydrology at the request of the Water Directorate of the Department of the Environment. Subsequently, groundwater level data were included in the Hydrological data UK publications.

Publication of the Yearbooks in the Hydrological Data UK series was discontinued following the 1995 edition when the primary dissemination mechanism for river flow data became the National River Flow Archive retrieval service which has subsequently become largely web-based. The commentaries on hydrological conditions incorporated in the Hydrological Data UK Yearbooks have been superseded by the broader range of material published under the aegis of the National Hydrological Monitoring Programme.