I thank the Chair of the Environmental Audit Committee, the right hon. Member for Ludlow (Philip Dunne), for his report and for his speech. It is a pleasure to follow the hon. Member for Kensington (Felicity Buchan), who gave a very clear description of the flooding issues in central London, many of which my constituents have also experienced in the past couple of years, particularly in Chiswick. In previous years, flooding affected much of my constituency. Thames Water is still in the process of replacing the Victorian freshwater pipes, and when they burst because they are so old, we still get flooding; it is not as bad as it used to be, but we are not out of the woods. I thank her for raising those issues.
For many years as a councillor and for the last seven as a local MP, I have been dealing with Thames Water, particularly in relation to its management of the Mogden sewage works in Isleworth, Britain’s third largest sewage treatment works. From the many emails and messages that I have received from constituents, I know that people are rightly frustrated with Thames Water and with Ofwat, which is supposed to regulate our water companies.
The worst local impact of Mogden was the flooding of the Duke of Northumberland’s river with raw undiluted sewage in January 2021. The flood occurred after a break in a brick wall separating the river, which is a freshwater stream, from the Mogden works’ main incoming sewage pipe. The inlet sieve into the works was blocked with silt, and the incoming sewage pipe, which is over two metres wide, filled to the top. When the incoming foul water had nowhere else to go, a weakness in the roof of the intake burst and poured into the Duke of Northumberland’s river running alongside it. That small river was subsumed by sewage that flooded into homes, gardens and two parks in Isleworth. It would have been far worse if an affected resident had not coincidentally known the holder of a key to the sluice gate into the Thames. Opening it relieved the pressure on the Duke of Northumberland’s river before the fire service could get there, and long before Thames Water worked out what had happened.
The flood had a devasting impact, especially on local residents who had sewage water flowing into their back gardens and in some cases their homes. A number of people also wrote to me to rightly express their worry about the impact on the wildlife in and around the precious Duke of Northumberland’s river. I was very concerned to discover that two months after the flood, there were still debris and sewage waste in and around the river and the river banks.
A small group of great volunteers work to keep the river tidy, but it is not fair or right to expect them to have to clean up afterwards. Local councillors, such as Councillor Salman Shaheen, have been persistent in pushing Thames Water to clean up the mess.
More than a year after this disaster, Thames Water has not yet started the inquiry that it promised us, although it has admitted that it still does not know the reason for the silt build-up that blocked the main inlet to the works, and I did manage to get it to admit that such a situation had not featured in its risk register; it certainly will now.
However, this is not the only recent disaster originating from Mogden. We now know, thanks to the Select Committee, that in October 2020 Thames Water pumped 2 billion litres—2 billion, not 2 million—of untreated sewage into the Thames in just two days. That is shocking, but it is part of a growing trend. In 2020, 3.5 billion litres of untreated sewage entered the Thames from Mogden—seven times as much as was dumped in 2016, just four years earlier.
As I have already pointed out, the Tideway tunnel starts downstream of Mogden, so it will not take these discharges. Not only are the discharges a gross environmental crime; they affect many people’s leisure activities. In our part of west London, the Thames plays a huge part in many water sports, such as rowing, kayaking and paddleboarding. Residents walk their dogs along the Thames. Should they really be expected to do so while it is full of sewage?
I wish I could say that these were the only negative experiences that my constituents have had with Thames Water, but there are ongoing and long-running issues involving Mogden sewage treatment works. For years, residents of, in particular, Isleworth and parts of Hounslow have all too often experienced the foul pong of poo
wafting around locally, and have also had to put up with the mosquitoes that breed in the stagnant water there and then come out and bite.