Anglian Water and Thames Water are trialling fat-coated “BioBullet” pellets in the fight against zebra mussels that infest water pipes and treatment works, costing the water companies £1.5M a year.
Thames Water and Anglian Water are running a six-month trial of the microscopic pellets at Thames Water’s Kempton Park water works and at its Walthamstow water works in north east London, to kill zebra mussels from the Black and Caspian Seas.
The BioBullet, which is about 50 micrometres in diameter, has a fatty outer coating irresistible to zebra mussels, covering an inner centre that is toxic to mussels but harmless to humans and other creatures living in the water.
Thames Water and Anglian Water spend £1M and £500,000 a year, respectively, clearing zebra mussels from their infrastructure.
With no known predators in Britain to control them, zebra mussels’ numbers are ballooning out of control. Adult zebra mussels, which are no good to eat, can grow up to 4 cm long, and females can release more than 30,000 eggs per year. The free-swimming larvae quickly attach to surfaces where they live for up to five years.
Build-ups of mussels, and the shells of dead mussels, narrow and can eventually block water companies’ pipes.