Case Study 1:
Client owns large industrial estate in Manchester which suffers from flooding within the warehouse units during periods of heavy and prolonged rainfall. This results in downtime for business operators and insurance claims for the client. Drainage Consultants were asked to investigate and put forward a solution.
A CCTV survey was completed on a 750mm-diameter brick built culvert using a robotic camera system. The survey identified that the brick culvert was collapsing resulting in a significant cross sectional area loss, causing huge reductions in flow capability and flooding to the basement units.
Sonar Trace from a manhole 9 metres deep to the collapsing culvert approximately 30 metres upstream of the manhole. The area above the collapse was identified as being within a unit and close to a party wall. Following consultations with Surveyors and Engineers within the company a decision was made to submit a proposal to excavate within the unit to a depth of 9 metres to expose the collapsing culvert. The culvert had to be over pumped during this process and CCTV surveys had to be completed 4 times each day to ensure that works to expose the culvert did not cause the culvert to collapse completely before we had chance to repair it. Following the successful repair of the culvert, a UV cured liner was installed between 2 manholes at a distance of 64 metres.