Civil Engineering


A449 Find & Fix

CCTV survey and remediation

The A449 had a lack of DDMS drainage data and a high number of recorded flooding hotspots along a 25km length. 

Sharing TM with Kier’s M&R team, Carnell’s CCTV survey teams were deployed on site at the hotspot locations, closely followed by our remediation team. Pipework failures were immediately reviewed by Carnell, with remediation proposals reviewed by the client the next day so they could be implemented on site the following night shift. 

A robust governance process provided transparency of the work being carried out, using DrainageViewer to enable justification of retrospective funding through before and after images of drainage asset condition. 

Find & Fix (Drainage)

Carnell have designed several survey and remediation packages which deliver quick and cost-effective solutions to improve the functionality of network drainage assets performance and extend their lifespan.

The adaptable process is devised in collaboration with the client to navigate each contract’s commercial / value management challenges to have the most effective benefit to road-users.


  • In areas of persistent flooding and little condition data, survey and remediation teams are mobilised in the same
    road space. Where safety-critical defects are identified, proposals are discussed with the client and interventions swiftly undertaken using trenchless or invasive techniques.


  • Flooding hotspot shapefile from DDMS uploaded to DrainageViewer. 
  • With little survey information to go on, only flooding hotspots from the client could be used to identify areas to tackle. 
  • GPS survey of 612 point items. 
  • CCTV survey of 18,681m pipework. 
  • Jetting of 17,316m pipework. 
  • Dewatering of 552 chambers / gullies. 
  • CIPP patch repairs x 99. 
  • CIPP pipe lining of 173m pipework.