Permission is being sought by a water company for more HGVs to access its treatment works site – which produces a “rotten eggs-like odour” – on bank holidays.

Southern Water has applied to change a restriction which is currently in place at its Wastewater Treatment Works (WTW) in Kinney’s Lane in Ashford, to more than double the number of vehicles accessing the land, despite the fact it could affect nearby properties.

At the moment a condition imposed by Ashford Borough Council (ABC) means only six HGVs can access the site in Kennington on bank holidays, a restriction designed to “ensure minimum disturbance” and to avoid “nuisance to the local community”.

But Southern Water says this restriction is causing “operational difficulties” and limits the site’s capacity to “effectively treat wastewater flows”.

As a result, it has asked ABC if it can up the number of HGVs allowed on the site on bank holidays to 15 as it is the “only pragmatic and reasonable approach” to ensure operations remain efficient.

The firm says it will help reduce odour issues.

In a letter to ABC, Phil Jameson, principal town planner at Southern Water said: “This will improve the operational efficiency and resilience of the site and will minimise the risk of amenity and odour issues associated with sludge storage.

“Allowing for additional imports of liquid sludge on bank and public holidays will also reduce the likelihood of sludge backups and resilience issues at other WTWs in Kent.”

The Ashford WTW is a key site in the Southern Water network that provides wastewater treatment services to Ashford and the surrounding areas.

It is also a Sludge Treatment Centre (STC) that serves a large part of east Kent which involves removing the water from the sludge to reduce its weight.

Residents in nearby the Little Burton estate say the area often smells like “rotten eggs” due to odours wafting across to their homes from the site.

This is despite the water company spending £4.3 million on upgrading the sewage works.

Southern Water says it hopes the changes could improve foul smells further.

While the company accepts an increase in HGV movements “has the potential to affect the amenity of residential properties”, particularly those in Kinney’s Lane, it insists the increase it has asked for has been “kept to the minimum necessary”.

The letter adds: “Ideally Southern Water would like to import sludge to Ashford WTW on a regular basis seven days per week however the amenity impact this would have is noted.

“Therefore, we believe that the proposed increase in HGV movements on bank holidays only is a pragmatic and reasonable approach to ensuring the efficient and effective ongoing operation of the WTW.”

A Southern Water spokesperson added: “We are requesting permission to increase the number of Heavy Goods Vehicle movements during Bank Holidays into Ashford Wastewater Treatment Works.

“This would allow us to keep the site running around the clock as it needs to, and reduce the risk of technical failures.

“We contacted neighbouring customers in Canterbury Road and Kinney’s Lane in advance of this planning application being submitted, and will keep them updated.”