Furious residents say their estate still smells like “rotten eggs” - despite a water company spending £4.3 million upgrading a nearby sewage works.

Southern Water claims its work at Ashford Wastewater Treatment Works in Kennington has “already made a massive difference” following years of complaints about an “unbearable” pong.

But many living on the nearby Little Burton estate say the foul stench still stops them from opening windows in the summer, while some even have to restrict their children from playing outside.

More than 100 people have now signed a petition calling on the company to resolve the issue as it continues to "greatly diminish" their quality of life.

Southern Water says it has received positive feedback since its multimillion-pound upgrades were completed in November last year, which included covering three tanks involved in treating sewage.

But Nigel Clarke, who has lived on the estate for almost 20 years and started the petition, says the area "still smells like rotten fish and eggs".

“It's always been a problem but it's getting worse every year," the 64-year-old said.

“You can be sitting out in your garden on a lovely sunny day, or having a barbecue, and all of a sudden you get this cloud of smell coming over.

“It makes you feel sick, it gives you a headache, and you just don't feel like eating.

“Honestly it is unbearable and you have to go indoors and shut all your windows which is not good on a hot day.

“Some people say ‘if you don't like it just move out of the area’, but we don't want to move out because it's a really nice area and it's not that simple either.”

Mr Clarke’s petition has so far reached 156 signatures.

It comes just 10 months after Southern Water said its scheme had “tackled odour concerns in a number of ways”, including changing the location of where sewage solids are stored before being removed from the site.

But Little Burton resident John Denham says the “unpleasant smell” has been a problem since he moved in 17 years ago - and has still not disappeared.

“We have had to put up with the sewage smell for years and it’s unpleasant,” the 44-year-old said.

“We do smell the fields being sprayed too but that's a different type of smell, we can tell the difference between the two.

“It's not all the time, but when it does materialise, it lasts about a week or two which suggests it's when routine work is being carried out.”

One mum who lives nearby says the smell is so bad it makes her want to move away.

“It's terrible and really unpleasant, you can't have the windows open, and you can’t even put the washing out in the garden because all the clothes will smell,” she said.

“There are periods when it's every day, then it will die down a bit, but even if it’s one day in a month it is still too much.

“It does make us want to move. It's bad all year round but you notice it more in the summer because the windows are open and we're outside more.”

Other residents say the severity of the odour varies depending on which part of the estate people live in.

But even those who are sheltered from it say more needs to be done to solve the issue.

Jim Beeching, 53, who has lived in Little Burton for 20 years, says thankfully his home is not too badly impacted.

"We get it every now and then, but different parts of the estate get it worse than we do,” he explained.

"Sometimes when I work from home I can smell it but I haven't smelt it as much this summer.

"But I still think more needs to be done to sort it out, especially as they are building more houses nearby.”

Despite the concerns, Ashley Corgat, 37, says the smell is not that bad and “living next to a farmer's field would be a lot worse”.

“A bad day might happen four days a year when they do certain work but we have lived here happily for 18 months,” he said.

Resident Jackie Snook says she has actually seen an improvement since she moved in 20 years ago.

“At times I can smell a horrible smell but other times I don't notice it,” the 66-year-old said.

“When we first moved here when the house was first built, I thought the stench was worse and more frequent than it is now.

“But then again if they have spent that much money on it, we shouldn't get that smell at all and obviously we are.”

Southern Water says it thinks “other factors” could be contributing to the smell, such as muck spreading and low water levels in the River Stour that may generate fish smells in the summer.

Its team is also investigating “poor build design” on the Little Burton estate as it says the Environment Agency has confirmed all new equipment at the sewage plant is operating correctly.

The company’s director of wastewater operations, John Penicud, said: “This work [the £4.3m project] is really important to significantly improve how we treat both waste and air quality for nearby residents who have in the past been impacted by odours.

“Feedback demonstrates the work has already made a massive difference and will take the learnings from this into other areas in our region.”

Bosses say workers at the site are now using a new live monitoring system and odour management plan “to keep on top of the issue”.

And they say “further technology” has been installed to stop gases involved in the treatment process from escaping into the air.

A spokesman for Ashford Borough Council (ABC) said the authority is monitoring the site with the EA and “working closely with Southern Water about odour complaints”.

The water company said it had worked “in close collaboration” with ABC during the upgrades.

In March, a further £6 million programme of works to install a new storm tank at the site began.

The new tank will increase the capacity for stormwater at the site by 1.8 million litres, meaning it will be able to handle 7.5 million litres during wet weather before it is treated and released.

The works will be completed by early 2025 and “will not cause any new odours around the site”, bosses say.

A spokesperson for the Environment Agency said: “Following reports of odour from Ashford Wastewater Treatment Works (WWTW) we have carried out odour assessments in the Little Burton area and have confirmed the presence of odours which may emanate from the WWTW.

“We are working with the operators, Southern Water to investigate the cause.

“Our investigations are ongoing and we are also liaising with ABC’s Environmental Protection Team.

“To help with our investigations, please continue to report any odour that you are experiencing to our free 24-hour Incident Hotline on 0800 80-70-60.”