Thames Tunnel Re-rail

Cleshar acted as Principal Designer & Contractor. The re-rail was required due to the heavy rail foot corrosion experienced under the Thames due to the salty atmosphere combined with stray current effects due to the mismatched NR/LO traction.

Cleshar were in a unique position to identify, analyse and mitigate risk through our unrivalled internal support functions. Key departments included our IMC department (Project and Maintenance teams) along with our TFL, NWR and GPX welding divisions

We undertook multiple surveys and stray current testing. Information was presented to our CREs, CEMs, and management teams along with key client parties. This information was assessed and collaboratively analysed during project risk reviews and key engineering meetings. There were key construction risks such as managing rail transport within a tunnel environment of 1 in 37 gradients, check curve complexities and bespoke nightly welding challenges. Key construction risks identified at design stage, enabled Cleshar CEM, CRE and LO engineers to make key value engineering decisions. Risks were expertly defined/quantified at pre-contract stage which enabled client governance authorisation. During the construction stage, Cleshar monitored risks in accordance with Project Risk management plan. Experienced safety critical and site management supplied key shift information to our CRE where risks were assessed and managed daily.

Cleshar gathered existing condition knowledge from our maintenance teams, historical records, and site surveys. This knowledge was assessed by our industry experts who prepared recommendations and options to our client so to make risk based informed decisions. The transfer of knowledge flowed through the project stages which lead to an efficient project handover to our Maintenance department and LO AMIS database.

Our project management ensured clients and all stakeholders were engaged and informed. Two key plans were our EMP and CPP. Share point was used as an information exchange and Amis for asset updates.

Cleshar were given clear programme end date by end of March which we achieved with a budgeted cost of £1.04m. We delivered the Project for £890k final account. The risk pot not utilised was a client cost saving.




Rail for London


Thames Tunnel

Project Value