THE borough’s biggest reservoir is being completely drained as part of an £800,000 project to strengthen its walls and replace vital drains and valves.

Work started last month to remove 923 million litres of water from Elton Reservoir so the massive refurbishment programme can begin.

Hundreds of fish — including a pike rumoured locally to be five feet long — will also be removed and taken to temporary storage ponds.

The reservoir, which is popular with walkers, anglers and sailors, is due to be full again by December.

Clive Mitchell, project manager for British Waterways, said: “The works which we are undertaking are vital repairs to comply with British Waterways’ statutory duties, and to ensure that the reservoir can operate safely at its full capacity.”

The reservoir, which is off Bolton Road and straddles the Bury-Radcliffe border, was constructed in 1842 and has a surface area of 22 hectares. Rather than a water supply, it serves as a feeder for the Manchester, Bolton and Bury Canal which is in the process of being partially restored.

The maintenance work will see valves, timber plugs and drains replaced, the spillway weir and channel repaired and additional embankment protection added.

Water is being removed through a pumphouse and drained into the Manchester, Bolton and Bury Canal, with any extra water spilling into the River Irwell.

It will be September before the reservoir is completely drained and work can be carried out on the bed.

Fish will be removed by a specialist contractor and kept in storage ponds in Chorley, before being returned later in the year.

The project is due to be completed in October, though it could be December before the reservoir is full again.

Despite the lengthy closure, the refurbishment is being seen positively by members of Elton Sailing Club, which is based on the reservoir’s banks.

Club manager David Moore said: “This is a job that has been planned for a couple of years and we are pleased that it is being done, despite the disruption. We won’t be able to do any sailing until November, so in the mean time we are holding a few social events and ticking over.

“We are looking ahead while the work is going on and seeing what we can do to improve the club. We plan to hold a big recruitment drive next year. We are determined to come back better and stronger than ever.”

Visitors to the reservoir are being advised to take care because large areas of deep mud have been exposed as work is carried out.

Warning signs have been erected around the reservoir and the public right of way on the embankment crest is closed.

Mr Mitchell said: “The reservoir is popular with walkers and during the works we are urging the public to keep to the designated footpath and not to walk on the exposed reservoir bed. ”