WORK has begun on the third phase of a major underground water clean-up project.
United Utilities is currently working on a £10m wastewater improvement scheme for the River Douglas.
Engineers will be working at five locations across the borough where the sewer system presently overflows into local streams during heavy rain.
These overflows are a design feature of the sewer system, working like a safety valve to relieve the pressure during heavy rain and prevent drains from backing up.
The work will significantly reduce pollution into several of the local watercourses which flow into the River Douglas.
By building new larger sewers, underground storage tanks and sieve-like screens, the system will be able to handle more water for full treatment.
On the occasions when it still has to overflow, the screens will strain out any sanitary litter including cotton buds and wet wipes.
Work on a third overflow started this week at Greenwood Avenue, in Norley Hall,
A large rectangular storage tank will be built beneath the grassed area and will be able to store some 11,000 litres of water during heavy storms – enough to fill more than 120 baths.
There will be temporary parking restrictions on Greenwood Avenue and Montrose Avenue and work is expected to take until next summer.
Two further phases of work are planned - at Bamfurlong in the next six weeks, and then at Standish next year.
The first phase of work, on Warrington Road near to Skew Bridge, in Newtown, began in July and is nearly complete.
Engineers are in the process of reinstating the area where they had been working.
Another of the overflows is on Warrington Road, near McDonalds, and engineers began work here in September on a large underground storage tank.
The work is due to last for nine months.
Kerry Towers, project co-ordinator for United Utilities, explained: “By carrying out these works we will be able to prevent dirty storm-water eventually flowing into the Douglas.
“This will help local wildlife flourish as we meet the demands of the 21st century.
“We’ll keep local residents up to date as our plans progress.”