Professor Chris Binnie who chaired the original Thames Tideway Strategic Study which recommended that a tunnel should be built, has published a new paper based on Environment Agency data setting out reasons why the Tunnel should not now go ahead.

Professor Binnie has undertaken a detailed analysis of new data from the Environment Agency, obtained under the Freedom of Information Act, concluding that it demonstrates that the River Thames already complies with the Water Framework Directive and the European Waste Water Treatment Directive.

The existing central London sewerage system combines foul and storm water in one pipe with combined sewer overflows into the Tideway during storms. This has resulted in excessive storm discharge and adverse environmental conditions. The European Urban Waste Water Treatment Directive (UWWTD) has the objective “to protect the environment from the adverse effects of water discharges.”

A programme of work including upgrading of the sewage treatment works and the construction of the Lee tunnel is nearing completion at a cost of about £1.2bn.  Information has been received recently of the benefit that has been achieved so far. This Review considers whether the benefit of the current works is sufficient or whether the Thames tunnel is still required.

Prof Binnie concludes that ‘post the Sewage Treatment Works upgrades, which are now operational, plus the Lee Tunnel, operational in 2015, and, if thought appropriate, the installation of floating booms and other low cost measures to collect floating debris, the Tideway will meet the requirement for no significant adverse environmental impact from Combined Sewage Outfalls.”

“Thus, there appears to be no reason at all to go ahead now with the Thames Tideway Tunnel in order to meet the requirements of the Urban Waste Water Treatment Directive, since the Thames already complies with that EU Directive.’

The detailed 84 page paper Thames Tideway - Review of Tideway spills and their environmental impact, makes a number of key points on the grounds querying the need for the Tideway Tunnel project. The report draws attention to the fact that the Environment Agency state that, since the upgrade of Mogden STW in March 2013, despite many untreated storm spills, they are not aware of any instances when spills have caused significant adverse environmental impact on the river water quality.

Referring to a sewer model and a river water quality model set up by Thames Water which showed that only the Thames tunnel would be sufficient to meet the required dissolved oxygen standards, Professor Binnie points out that Thames Water itself has identified many potential errors in the data and stated that “it is unlikely that it will ever be possible to acquire sufficiently comprehensive data.” to produce robust output.

The report says that comparison with the dissolved oxygen readings, and the fish kill records show the model to overestimate the fish kills and the sags in dissolved oxygen content of the Tideway. The Environment Agency’s own record of fish kills in the Tideway shows 3 fish kills over the last 10 years, with only one, of one fish, caused by overflow from the CSOs to be connected to the Tideway tunnel.

Professor Binnie also says that once the Lee tunnel is operational in late 2015, halving the spill volume, then the water quality in the Erith area will improve further, concluding;

“Post the Lee tunnel and the STW upgrades, it would appear that, similarly to the current Mogden STW, storm discharges from the Tideway CSOs would not cause significant adverse impact on the ecological quality of the river, and, in line with the Environment Agency statement about Mogden, the Tideway ecology should be regarded as satisfactory under the terms of the UWWTD.”

Lord Berkeley, who has consistently opposed the construction of the Tideway Tunnel, has now written to Lord De Mauley, Minister of State at the Department for Food, Environment and Rural Affairs, urging the Government to stop any further expenditure on the project.

 Lord Berkeley commented:

‘There can no longer be any credible argument for going forward with this costly Tunnel project, £4.2bn at 2011 prices plus financing, operating and maintenance costs.”  

 ‘Cancellation will save some 14 million Thames Water customers having to pay an extra £80 per annum for the foreseeable future to fund this expensive folly. The time to stop this waste of money is now.’

Click here to read Thames Tideway - Review of Tideway spills and their environmental impact in full