AHDB field drainage guide gets essential maintenance

The basic principles of field drainage, as well as maintenance and installation information, are the subject of a revamped practical guide by AHDB.

By refreshing knowledge on drainage, it is hoped that the new-look guide will play an important role in stemming the decline in UK drainage investment.

Well-drained soils enhance the resilience of land by making it more able to withstand weather shocks.

Fields have been drained for agricultural use for centuries but the last significant nationwide investment occurred in the wake of World War II, when grant aid and advice was freely available as part of a productivity push.

Grant aid and free advice dried up in the 1980s and the rate of installation of new drains has declined.

Good field drainage is of particular value to growers on heavy soils, in high rainfall areas or where the water table needs to be controlled.

Maintaining drains

The guide describes how a relatively small investment, such as locating and maintaining existing ditches and drains, is likely to reap rewards relatively quickly.

Useful guidance to help farmers locate outfalls, such as checking ditches after rainfall in autumn and winter when there is less vegetation, is detailed in the guide.

For growers considering installing a new system, the guide provides outline costs and real-life case studies. Costs can vary greatly and growers looking to invest in a new system are advised to seek the opinions of experienced land drainage consultants and contractors.

Not just drains

All drainage systems work best in tandem with good soil structure, because if soil is compacted it impedes the flow of water to the pipes. In fact, maintaining good soil structure may even avoid the need for capital investment.

The guide also features information on subsoiling and topsoil loosening and details when it is appropriate to supplement the drainage system with mole drains.

Download the guide: ahdb.org.uk/knowledge-library/field-drainage-guide