What is an Internal Drainage Board

The responsibilities for the management and maintenance of flood defence and drainage systems in England and Wales have been placed by Parliament in the hands of drainage authorities.

Whilst district and county councils have limited drainage powers, the vast majority of the necessary flood protection is carried out by drainage boards and the Environment Agency.

Drainage Boards

Drainage districts have been established in the most drainage sensitive parts of the country being the low lying areas, much below sea level, constantly at risk from flooding. The drainage districts, administered by drainage boards, vary in size from a few hundred acres to over 100,000 acres, aggregating in total to some 3 million acres. Thus, unlike other statutory authorities, which blanket-cover the country, drainage boards only administer districts that directly benefit from their operations which include the improvement and maintenance of rivers, drainage channels and pumping stations. Over 2 million acres of land, including large areas developed with residential and industrial property, depend on pumping stations to evacuate water to prevent permanent flooding and water logging.

In all drainage districts it is of paramount importance that open drainage channels are regularly dredged and vegetation controlled. In some districts, underground storm water culverts need to be kept in good repair and maintained. Without all these essential works the environment and conditions for persons living and working in the areas would become intolerable; everyone would suffer. Services would become inoperable, properties and gardens would be affected and prime agricultural land would be unable to yield the wide range of crops and this could create food shortages with associated price increases.

Drainage boards have the advantage of being locally based, providing a local service to the community with locally elected members in control.

The members are elected directly by farmers within a district, all of whom pay drainage rates to the board, or are elected councillors nominated by a district council to serve on boards within its area. Apart from the income raised through the rating of agricultural land, the boards serve a special levy on district councils reflecting the benefit received by domestic and industrial property in the district, and can also recover sums from developers in order to carry out works necessary to ensure that the presence of the new development does not create flooding/drainage problems.

Environment Agency

The Environment Agency has duties throughout the country and, besides keeping a watchful eye on other drainage authorities, has direct responsibilities for sea defences and the major rivers, including tidal sections, several extending many miles into the low lying areas. It promotes improvement work to increase the standard of flood protection and drainage and ensure that all the works are adequately maintained. This maintenance is vital to retain the flood risk at an acceptable level and includes routine repairs and vegetation control to both sea and river embankments. It is necessary to ensure that the flood carrying capacity of channels is not reduced and this is achieved through regular dredging and the removal of obstructions including the seasonal weed growth, which, if unattended, would cause both short and long term problems. In particular sensitive coastal and inland areas the Agency has developed flood warning systems for use when defences are at risk of over-topping or channels are unable to contain flows.

General powers and functions of Drainage Authorities

All drainage authorities have general supervisory functions and powers. They can make byelaws to ensure and protect adequate drainage systems and works, like sea defences; they can require owners and occupiers of properties to remedy defects in systems, for example where flows of water are impeded through defaults of persons; they control the erection of structures affecting watercourses and the culverting of watercourses which require their special consents. From new hard paved areas the flow of rainwater increases to a rapid rate and an important role of drainage authorities is their participation in planning the development of land. They consider the implications of proposals by assessing risks of flooding, both to areas subject to proposed development and adjoining areas, and their advice is given to planning authorities and all other interested parties. Their expertise is called upon to ensure that vital flood protection works are carried out as a necessary part of the infrastructure for developments; the drainage authorities themselves often undertaking the works.

Historical Footnote

Public bodies are required to deal with matters which are beyond the scope of the individual. This need was first recognised in this Country in 1252 with the creation of the Romney Marsh Commissioners, whose corporate planning and combined effort was required to create a living and working environment within the Romney Marsh. This model approach was repeated many times, particularly in the seventeenth century, and preceded other forms of truly local administration. These historic areas of drainage sensitivity are today within Drainage Districts, the Boards being the direct descendants of the early Commissioners with similar responsibilities.

The only thing that has changed over the centuries is that these areas are more populated; people’s expectations in terms of flood protection are substantially higher, and the nation’s dependence on the food produced within them has increased dramatically.

The need for a public authority to provide a service in areas dependent upon flood defence and land drainage was established long ago. The work of Drainage Authorities is today as vital as it has ever been.


Area of Responsibility of Lower Severn Internal Drainage Board

The Board has an administrative area covering over approximately 21,000 hectares of land alongside the Rivers Severn, River Frome in the Stroud Valley, the River Leadon and the River Little Avon in South Gloucestershire.

The area of the Board extends into Eight Local Authority areas as follows;- Herefordshire, Forest of Dean District,Tewkesbury Borough, Malvern Hills District, Gloucester City, Stroud District, Bristol City and South Gloucestershire Councils. The board is a member of the Association of Drainage Authorities based at Huntingdon in Cambridgeshire.

Members of the Board

The Board’s members consist of 14 directly elected members who comprise owners or occupiers of land within the Board’s area, together with 15 members nominated by the Local Authorities that contribute to the Board’s funding. The latter members represent the business and householders within the Board’s area. Elections are held every 3 years for the directly elected members. A full list of current members is available from the Principal Officer during office hours.

Staff of the Board

The Board’s Officers are headed by the Principal Officer. The Board’s direct labour force is engaged on the maintenance and improvement of approximately 300 miles of watercourses and drainage rhines within its area aided by Contractors as and when needed, particularly in the North of its area, and to maintain the various pumping stations which are necessary to evacuate water in times of heavy rainfall or when the tides are high in the River Severn. The Board’s employees are based at its purpose built office and depot complex at Oldbury Naite, near Thornbury in South Gloucestershire.

As well as maintaining its drainage systems, the Staff of the Board are consulted by all of the relevant planning authorities in respect of development proposals which may either infringe the Board’s Byelaws or have an impact on its area as a result of increased rates of surface water runoff. This is a requirement of the Department of Transport and Region’s guidance note Policy Planning Statement 25 issued in December 2006.

For areas where large scale development is planned e.g. in the Severnside Area at Avonmouth and Severn Beach the Board has produced “Guidance Notes for Developers” available from the Board’s offices.

As the Drainage Authority in the area the Staff administer the issue of consents to discharge water within its area or for structures such as bridges and culverts proposed to be erected over watercourses. This is a requirement under the Land Drainage Act 1991 and the Board’s own ‘LAND DRAINAGE BYELAWS’ available from the office.

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