Overview
- Thames Water says it clears the equivalent of more than four Olympic-sized swimming pools of Quagga mussels from its network each year and spends over £6 million annually on removal, disposal and related maintenance.
- Engineers frequently find hundreds of thousands of mussels in a single operation and now use high-powered hydro-blasting and, in severe cases, diving teams to clear blocked pipes and pumps.
- Quagga mussels reproduce extremely fast—one adult can produce about one million eggs per season—and they attach in dense colonies to hard surfaces, which narrows pipes and reduces flow and efficiency.
- Other invasive animals such as signal crayfish and Chinese mitten crabs are worsening the threat by burrowing into banks, speeding corrosion and increasing silt buildup, which raises the risk of service disruption and local flooding; the company has urged the public to follow 'check, clean, dry' guidance for boats and gear.
- Thames Water says the problem has intensified in recent years, links growth to warmer water linked to climate change, and has committed to expanding monitoring, prevention and biosecurity work over the next few years to protect infrastructure and river health.