Silverton Mill – Redirection

D S Smith

3 years

£4.5m

Exeter

Location & Overview

As Principal Contractors, we were required to demolish and remediate a former paper mill, comprising a large number of structures, pipelines, ducts, pits and soakaways, plus a large culvert that ran beneath the site. The mill straddled a major river (River Culm) and had heavy industrial usage dating back to the 1800s. The river ran through a large culvert for almost the entire length of the site. Significant pollution issues were present with contamination in the form of heavy and light hydrocarbons and asbestos in the soils.

Work, Challenges & Solutions

Construction of a temporary river diversion allowing the culvert and surrounding ground to be remediated without risk to the River Culm.
Demolition of the above-ground structures to ground level providing sufficient space for the river diversion, with the design and construction of the HDPE lined river diversion channel, including regulatory negotiation and agreement for the design.
Commissioning and maintenance of the river diversion during its operation and the monitoring of the River Culm for prediction of high flow conditions to prevent damage to the works and temporary channel.
Demolition and removal of the old culvert under the building and remediation of the contaminated ground.
Design of a new permanent river channel with enhanced environmental benefits and the construction of the new river post-remediation, including a groundwater base flow alleviation system, rock armour flow protection and restoration of grassed embankments.

Achievements

Turning a contaminated, industrial area which was unusable into a beautiful, environmentally clean countryside beauty spot.