Either of these alternatives would preclude the need for Thames Water to use Chambers Wharf or any site in Southwark:
- Short tunnels where relevant with appropriate mitigation elsewhere
- The Sewer Overflows (CSOs) responsible for over 90% of the pollution are concentrated in two areas, East and West of Central London.
- Consequently it is unnecessary and wasteful to build a tunnel in the central section of the river. This means no Super-Sewer in Southwark.
- Remaining CSOs can be tackled without connection to the Super-Sewer, as is now the plan for the one in Shad Thames anyway. This would still deliver a clean river.
- This solution would save an estimated 50% of the cost of the Super-Sewer scheme, roughly £2bn of our money. This could be invested in intelligent Green Infrastructure, mitigating two really critical risks associated with rainwater: floods and droughts – neither of which would be tackled by the Super-Sewer.
- This alternative is backed by the conclusions of the independent (i.e.: not controlled by Thames Water) Thames Tunnel Commission, chaired by Lord Selborne and endorsed by 5 London councils, including Southwark.
- Click here for more details.
- Change of Route – making use of Thames Water’s own industrial sites
- There would be a long tunnel, as Thames Water want but it would be driven from Abbey Mills in Stratford, Thames Water’s own property, towards the Kirtling Street site.
- There is plenty of space at or near Abbey Mills for a construction site whereas Chambers Wharf is in a densely residential area, with several schools right nearby.
- This solution would save the considerable expense of a site in Southwark by using an Eastern spur tunnel from either Greenwich to Limehouse, or Greenwich to Beckton.
- The spur tunnel carrying Greenwich sewage can be driven from Deptford where there are derelict wharves (such as Convoys Wharf) well away from residential areas.
- Tunnel boring machines can either be dismantled/buried or a hybrid tunnel boring machine employed that can deal with changes in geology. This would likely save money (only one TBM instead of two).
Aspects common to both solutions
- Both Ofwat and the Environment Agency say they want as few major sites as possible, to reduce cost and environmental impact.
- There is no sense in having a major construction site in Southwark, since Thames Water – having been pressed hard – has now found a solution to remedy the small overflow at Shad Thames without the need to connect it to the Super-Sewer, even if it were to run in the area.
There are in fact many variations on these two main alternatives that must urgently be properly evaluated. This will provide Thames Water with several options which would avoid having an unnecessary (and expensive) additional site in Southwark. Engineers we have consulted say these options are just as valid technically as those proposed by Thames Water. Our campaign will continue to put relentless pressure on stakeholders to ensure their due consideration.
Please don’t hesitate to get in touch with the campaign
Comments or questions are welcome