Facts & Figures

Cost £21.5 million includes additional spend of just over £2.5 million to remove contaminated ground from the site and to improve flood conveyancing and navigation of the Prescott channel
Funding partnership between the Olympic Delivery Authority, London Thames Gateway Development Corporation, Transport for London, Department for Transport and British Waterways
Creates access for large (350-tonne) barges from the Thames four to six hours a day
Each 350-tonne barge can carry the equivalent of 17 lorries
The lock can accommodate two barges at a time, equivalent to 35 lorry journeys
Will have a 62m x 8m chamber with two pairs of hydraulic 'sector' gates
Requires adjacent water control structure comprising two 'fish-belly' sluice gates, plus similar structure on Three Mills Wall River
Work began in March 2007 and will take just under two years to complete
Built on the site of an historic sluice on Prescott Channel, which was built in the 1930s and named after Major Prescott, a former chairman of the Lea Conservancy Board

Bow Back Rivers will be navigable 24-hours a day north of Three Mills
The navigable dimensions will be 2.4m deep with 3m headroom
Could transport up to 12,000 tonnes of construction materials each week (34 loaded barges)
Could take up to 1,200 lorry journeys off congested local roads each week
Each 350-tonne barge can carry the same as 17 lorries, saving up to 34 lorry journeys each
Less than a third of the amount of fuel is needed to move materials by water than by road, releasing less than a sixth of the pollution
The waterways of the Lower Lea Valley carried 2million tonnes of materials a year in their heyday around 1900

up to 1.75 million tonnes bulk construction materials moved by barge
up to 170,000 lorry journeys saved
up to 4,000 tonnes of CO 2 saved
up to 175,000 tonnes moved by barge each year after 2012 through legacy development and potential waste transfer
up to 17,500 lorry journeys saved each year after 2012
440 tonnes of CO 2 saved each year after 2012
potential to generate annual 160,000 KWh hydro power through restored tidal mill which can power a small village of up to 40 homes