HS2 River Avon

Dewatering to support the construction of a temporary bridge and haul road across the River Avon 

Objective

To support the construction of the HS2 scheme, a temporary bridge, working platforms and haul road was to be installed across the River Avon.

Scope of Works

As part of Phase 1 works at River Avon site Stuart Wells was contracted to install 3no groundwater monitoring wells. All wells were cored using air/mist rotary drilling methods.

Two of the boreholes were drilled to146 mm Ø, 25m deep. Packer testing was undertaken in these monitoring wells, followed by the installation of dual standpipes. The packer tests were carried out in accordance with BS EN ISO 22282-3:2012

After installation of the dual standpipes in all 3no boreholes, variable head testing was undertaken.

An additional pumping test was carried out, with a total of 12 wells across the site as part of the monitoring network.

Solution

Stuart Wells successfully dewatered the site at the River Avon to allow the construction of a temporary bridge, working platforms and haul road in dray and stable conditions.

These temporary structures supported the construction of the High Speed 2 programme, the UK’s new high-speed rail network.