9 April 2023
We have raised the following points in our response to the Thames Water Consultation on the Water Resources Management Plan 2024. These relate to Mogden Sewage Treatment Works and the Teddington River Abstraction scheme:
We encourage Thames Water to target less water per person per day. This should come down from the proposed 123 litres per day to the government’s national target of 110 litres per day or even less. This can be done in conjunction with new tariffs, such as charging more per litre for those who use excessive water – with safeguards via social tariffs for those who need more (eg some disabled).
We encourage Thames Water to do much more to fix leaks. As in the graph below (from the display at the Twickenham consultation event on 3rd March 2023) we want Thames Water to go for the “High Plus” scenario (brown line) that radically reduces water leakage to just over 400 Ml/d by 2030. This may cost more and cause more disruption than new infrastructure but we consider it would be worth doing in the long run.
With more ambition on reducing consumption and fixing leaks some of the infrastructure projects, such as the Teddington River Abstraction scheme would be unnecessary. We have asked Thames Water to look into this.
On page 27 in Table 6-1 of the consultation document Detailed feasibility and concept Gate 2 document it shows very large whole life carbon for Mogden and Teddington line items for the extraction scheme. This is possibly in excess of 1 Million tonnes of Carbon Dioxide equivalent. For just one infrastructure scheme, this is excessive when we are trying to reduce emissions to zero as soon as possible to limit world temperature rises to 1.5C in the climate emergency. If at all possible we want to avoid building schemes of this type if there are alternatives such as reducing consumption and not wasting water via leaks.
We are concerned about the impacts on water quality. The water quality of the Thames is already not ‘Good’ status. It is in the Thames River Basin Management Plan to achieve Good status and this is also in the London Plan (page 358). But there is no good plan to achieve this. The stretch of the river from Egham to Teddington currently has ‘Poor’ ecological status. See Environment Agency map. Such schemes as the Teddington extraction should not be considered while the water quality is not ‘Good’. ‘Good’ status should be achieved first – and then a proper assessment of the impacts of the extraction scheme can be made against good water quality rather than poor water quality. Otherwise we are risking further deterioration from an already ‘Poor’ status. Such deterioration is not acceptable according to the Environment Agency environmental objectives.
We have read the environmental impact documentation. We are concerned, given Thames Water’s current reputation, that we cannot rely on Thames Water marking their own homework as regards water quality. If the scheme does go ahead, we want to ensure that conditions are put in place for truly independent assessments of water quality impacts which involve local organizations. If the water quality impacts of any scheme do not result in water quality having ‘Good’ status, the scheme should not be used until the water quality has been improved to good status. Recent fines on Thames Water do not appear to have achieved the target of good water quality.
The extraction plant is a very large concrete structure. We are concerned that this plant will have considerable lasting impacts on a much loved semi-natural stretch of the Thames between Kingston and Teddington Lock. Thames Water staff informed me that the structure will block the path of the current footpath. It is also anticipated that during the construction phase there will be considerable biodiversity loss as the area will be turned into a construction site for several years. We oppose these impacts as the whole scheme is unnecessary.
We are concerned that the tertiary water treatment plant will use additional space within the Mogden site. On a visit to the Mogden site in April 2022, we were informed that options were limited for reducing the dumping of partially treated sewage into the River Thames off Isleworth, due to the lack of space within the Mogden site. It now seems that Thames Water are proposing to use limited space in the Mogden site for this extraction scheme while continuing to dump sewage into the Thames. We encourage Thames Water to solve the current problems within the Mogden site by limiting sewage dumps into the river Thames rather than use valuable space for the Teddington extraction scheme.
