Project Description

 Overview

To enable the draining and maintenance of the Grand Western Canal, drain plugs were built at various points. The outlet was approximately 8inches in diameter, sealed with an oak constructed frame and door, and plugged with clay to prevent it from leaking. One end of the door was hinged, while the other had a chain leading up the canal bank that could be pulled up and opened from the canals edge. Our task was to locate the leaking plug, which was at one point deemed to have perished altogether, and block it to render it redundant.

 

Challenges

To gain access to the canal bed, we installed a dam system either side of the approximate location of the plug and pumped water out. The 800mm of sediment build up made the task all the more hazardous – increasing the risk of getting stuck or the dam collapsing. To minimise the danger, we carried out detailed risk assessments and rescue procedures to ensure the safety of our people – specially trained in this type or work.

 

Results

Using historical drawings, we were able to locate the chain – buried in silt. We built a small sandbag dam, enabling us to excavate the silt, locate the plug, lift the door and reveal the drain. The drain was plugged with clay and then concreted to prevent any further leaking. By reinstating the lid and clay over the door, we fixed leak.

 

Quick facts:

Client: Devon County Council

Value: £25,000

Project type: Canals & Waterways

Duration: 1 week