Plans to tackle the stink of a sewage plant on the Forth in time for the opening of the Queensferry Crossing are firmly in place.

Visitors to Fife can often be met with a horrible stench from the premises on the north side of the Forth, but Scottish Water have now acted to remove the smell as much a possible with a £2.2 million spend.

The water and sewerage provider has lodged plans to Fife Council which will involve the construction of a new building with additional equipment such as removing the temporary external sludge press, replacing the sludge belt thickener and upgrading the associated odour control and air handling units.

The new system requires kalic, lime agent used to prepare the sludge cake for land disposal, so a kalic tank will also be installed at the works, which moves all this equipment indoors.

They also say a short new section of an internal access will also be required as part of the works.

However, Scottish Water did confirm last month that stink would not be completely eradicated.

A spokesperson at the time said: "It won't eradicate the odour completely, you can never get rid of it as there are so many contributing factors, but it's going to make a marked difference.

"We are constantly striving to manage the odours from our waste water sites and make sure there are plans in place to ensure any issues don't escalate."

Dunfermline Waste Water Treatment Works, which serves 82,000 people across Fife, is located on the B981 between Inverkeithing and North Queensferry.

The new facility proposed will sit over 400m away from the nearest residential properties and will be built on brownfield land.

There is no public access to the premises and road users will only see the top of the new building which is largely shielded by woodland.

The replacement of equipment will also reduce noise levels in the area.

Environmental Health has also submitted a statement to say they are in support of the plans.

The catalyst for the major upgrade, timed to be complete before the August 30 opening date for the bridge, was the end of long-term contract with an external operator and the opportunity to better control and manage the smells coming from the plant.

The Scottish Water spokesperson added: "It should make a huge difference and we're certainly hoping any odour problems can be addressed much quicker than previously."

The "terrible stench" has long been an issue with Alex Rowley MSP stating in 2015: "It’s got the point where people in cars look at each other and say, ‘It wisnae me!’"

Fife Council previously identified the principal sources of odour, including the release of sulphide and other smells from septic sludges; the release of ammonia from the addition of lime to sludge cake; the transfer and storage of lime-treated sludge to open bays; the transfer of lime-treated sludge by diggers to lorries; and the movement of lime-treated sludge across and away from the site.

Bill Elliot, Scottish Water’s regional community team manager, added: “Since December 2016, Scottish Water has worked hard to make these substantial improvements to Dunfermline Waste Water Treatment Works.

“The substantial £2.2m investment will enable us to provide a much-improved service to customers across Fife for many years to come.”