Dewatering requirements for new railways are mainly associated with tunnel approach structures, deep cuttings and underground stations. Also over time older railway infrastructure will require repair or updating. These projects are particularly challenging as it is usually necessary to avoid or minimise impact on the existing live train services while the works are undertaken. Even for new build works adjacent existing live railways are often in close proximity.
WJ has expert designers and site staff all, experienced with assessing and managing the constraints imposed by works on new and existing railway infrastructure. WJ have an enviable record of delivering successful, high quality and to programme dewatering for rail projects across the globe, having worked on Crossrail and HS2 in the UK, Eglinton LRT in Canada, and Lodz High Speed Railway in Poland.
Shafts & Tunnels
There are many techniques available for both shaft and tunnel construction. Some techniques can be carried out in ‘wet’ conditions but particularly for larger shafts, open cut tunnels, cross passages and complex underground junctions it is quicker and very much safer to reduce groundwater levels so that the excavations are in stable ‘dry’ ground. WJ can provide expert advice to clients on the viability of dewatering strategies in any particular geological setting at an early stage in a project development.
WJ also has low headroom drill rigs and compact pumping plant essential for work in restricted tunnel environments. WJ has also developed techniques and associated plant for installing wells out of tunnels into pressurised sand horizons using a combination of preventors, drill through valves and lost bit drilling.