Old engineering technique promises new rewards

A civil engineering technique used for thousands of years has proved cheaper and quicker than steel and concrete for stabilising slopes in a series of projects by consultant Richards, Moorehead & Laing (RML).

Dubbed 'willow engineering' by RML, it employs fast-growing live willow stakes and spiles to create terraces, which rapidly restore stability and prevent further slippage.

"Willow engineering promises potential cost savings of 50-90% compared with sheet piling or gabion walls, together with the advantages of low long term maintenance, reduced environmental impact and greater aesthetic appeal," said RML managing director Ivor Richards.

"Roman and medieval engineers used the technique and it has continued to be employed on a small scale for centuries.

"We have simply developed it into a practical modern system and proved that it offers an effective solution to many present day problems," he said.

RML believe the technique has tremendous potential as a mainstream engineering solution in a wide range of applications, including building developments, highways and river engineering.

"The cost savings are substantial because willow solutions can be installed quickly by manual labour and the material costs are low. No heavy plant is required, which also means no problems with access - a common obstacle, as many unstable slopes are steep and difficult to get at," added Richards.