Ful details of these impacts are set out in the Crossrail Environmental Statement and Specialist Technical Report : Water Resources.

Surface Water

The surface route sections of Crossrail (to the west and east of central London) will have limited impacts on surface water courses, as existing over-ground lines and water crossings will be used. Within the Central section of the route the Isle of Dogs station (which is being built within West India Dock North at Canary Wharf) and the tunnel portal at Pudding Mill Lane (which is being built next to the River Lea) will require construction works within water bodies.

Groundwater

The Crossrail route through central and east London runs through twin tunnels. Water will be pumped from the chalk to lower the water table during construction of the stations and shafts on the eastern part of the route. The abstracted water will either be discharged to Thames Water's sewers, or where practicable to surface water courses.

Mitigation measures

Crossrail is working with the regulatory organisations (particularly the Environment Agency) throughout the design process to discuss water resources issues and to ensure appropriate mitigation is incorporated.

During construction, control measures will be implemented as set out in the Construction Code (Annex 1 to the Environmental Minimum Requirements). Site specific water management plans will also be prepared for sensitive sites