Wasteland reclaimed as canalboat marina

The site at Cowley Peachey near Uxbridge is situated in the London Borough

of Hillingdon within the Green Belt and Colne Valley Regional Park in a unique

position at the junction of the Grand Union Canal and Slough Arm.

The work to rehabilitate the site consists of the following elements; the excavation,

filling and disposal of earthworks, the construction of a new marina basin,

the construction of a new visitor centre and sanitary station and the demolition

of an existing boathouse and the construction of a new boathouse.

Remediation strategy

The remediation strategy adopted by Nuttall involves minimising the removal

of material from the site and to this end all excavated material has been screened:

for example, concrete and brick is to be crushed for reuse and subsoils will

be used for bulk fill. All silts and subsoils have been tested extensively to

ensure their suitability and any material found to be unsuitable removed to

licensed sites. In total 90,500m3 of material, which consisted mainly of silt,

gravel and clay, was excavated.

A large 1.5 metre deep basin will accommodate 120 canal boats and its sides

will be sheet piled with a concrete capping beam. A 500mm thick clay liner and

clay leaning wall will provide an impermeable barrier for the marina basin.

Following the construction of the marina an extensive landscaping programme

will be undertaken reusing the excavated materials and the visitor centre, sanitary

station and boathouse will be constructed.

The project commenced in January 2001 and is due for completion in Spring 2002.