A water company said it is installing new equipment to improve the water quality in rivers in Lincolnshire.
Anglian Water said it was upgrading water recycling centres across the county to remove phosphorous from waste water.
Phosphorous is found in human waste, food, soaps and detergents and causes excess plant and algal growth in rivers.
The company said the investment would cost £45m and would “help to protect nearby rivers”.
Phosphorus also finds its way into watercourses from agricultural sources in addition to household waste.
The build-up of algae leads to a lack of oxygen in the water which can kill fish and other aquatic species and decreases biodiversity.
Regan Harris from Anglian Water, said: “Our current environmental investment programme is one of the biggest in the sector.
“We’re really pleased that these upgrades to our water recycling centres in Lincolnshire will help to protect nearby rivers and increase our resilience to climate change, by helping us make sure the waste water is treated to an even higher standard than usual before it’s returned to the natural environment.”
In 2023, Anglian Water recorded the biggest increase in raw sewage discharges of all of England’s water companies, according to figures from the Environment Agency.
Anglian Water said the figures had increased because the company now monitored 100% of discharges, and 2023 saw many incidents when heavy rain overwhelmed sewers.
Severn Trent and Anglian Water launched a plan to transform river water quality across their regions in 2022.
Both companies made pledges to ensure storm overflows and sewage treatment works do not harm rivers.
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