More than 10,000 oppose Thames Water plan to pump treated sewage into Thames

A mock up of how proposed Thames Water site may look like (Thames Water)
A mock up of how proposed Thames Water site may look like (Thames Water)

More than ten thousand people have opposed a plan to pour treated effluent into the Thames in a bid to combat drought.

Thames Water says the proposed abstraction site at Teddington Weir would draw off up to 100m litres of water a day from the Thames and replace it with “highly treated” effluent from Modgen sewer works in west London.

The water ‘recycling’ plan would mean water could be transferred to reservoirs in the Lee Valley in east London at times of drought.

But a petition, signed by 10,200 people, has raised concerns about the impact on river life, fish, insects and plants, because it will change the water temperature and its chemical make-up.

Magnus Grimond, of swimming group Teddington Bluetits, which started the petition told the Guardian: “There is scientific evidence that treated sewage can have ill-effects on water-based creatures, both through changes in the chemical makeup of the water and its temperature.

“These effects are magnified when river flow is low – e.g. in times of drought – and there is less water to dilute the treated sewage. It is just at these times that Thames Water will need to increase the flow from the Mogden sewage works.”

According to a Thames Water website advertising the plans, the proposals would help increase resilience to drought events by 2031 and are less expensive and quicker than other schemes such as a water ‘recycling’ plant in Beckton, east London.

However, critics have accused the utility company of not doing enough to stop leaks on its network, which equates to 25% of its supply.

Twickenham MP Munira Wilson has said she is “deeply concerned” about the plans. “The strength of local feeling on Thames Water's plans for a water recycling scheme is crystal clear,” she said.

“Losing a quarter of your daily supply to leaks whilst handing out millions in bonuses to execs is hardly a recipe for public trust.”

Thames Water was given the two-star rating by the Environment Agency for its environmental performance last year and a red rating for serious pollution incidents.

A Thames Water spokesperson stressed the proposals was in early stages and urged local residents to attend consultation events being held on it.

“We want to reassure local people that the proposed scheme isn’t any different to the normal water supply system and is designed to safeguard the river’s water quality,” said the spokesperson.

“The scheme will work by putting highly treated recycled water from Mogden Sewage Treatment Works, through an additional stage of treatment.

“Putting the recycled water into the river Thames above the Teddington Weir would ensure we protect the river’s water quality and would also compensate for the additional water abstracted during a drought.”

They added the company was planning to invest £1.6 billion on its sewage treatment works and sewer networks over the next two years.

A consultation into the plans, part of Thames Water’s Water Resource Management Plan to address water shortages, lasts until March 21.