Engineers often find hundreds of thousands of mussels blocking pipes across the network
Thames Water removes more than four Olympic swimming pools’ worth of mussels from its pipes across its network each year. The water company says it spends over £6 million each year clearing the invasive species, with engineers often finding hundreds of thousands of the shellfish clogging pipes in a single go.
Each year, the company’s engineers have to remove freshwater Quagga mussels, an invasive species in the UK, which are prolific breeders; a single mature mussel can produce one million eggs per season.
Often, mussels attach themselves to hard surfaces in dense clusters, which in turn restricts water flow and increases the risk of disruption.
The invasive species have posed a threat to the network for years, and this threat has recently accelerated. Engineers are now forced to use power tools such as hydro-blasters and, in extreme cases, divers to remove mussels from water infrastructure.
Mussels are not the only invasive species causing issues for the network; Signal Crayfish and Chinese mitten crabs also pose a threat, as they are prolific burrowers that cause extensive corrosion and siltation (narrowing of pipes), which in turn increases the risk of flooding.
Alexandra Collington, Biosecurity & Invasive Non-Native Species Officer at Thames Water, said: “Quagga mussels may be small, but the impact they have on our network is anything but.
“Whether crabs or crayfish, we see non-native invasive species damaging our infrastructure and causing disruption. They pose a significant threat to native wildlife and biodiversity, affecting the health and balance of our ecosystems.
“We’ve committed over the next few years to increase our work tackling the impact invasive species have on our infrastructure, so that our network remains safe and we can protect our waterways and wildlife.”
