THE ENVIRONMENT Agency is investigating after sewage flooded into gardens and school grounds near the A21 earlier this week.
A burst pipe in the Moat Lane area in Westfield is believed to be responsible for sending the sewage spilling onto the land, including part of the Claremont School grounds.
Mark Beaumont, director of the school, said the sewage had killed wildlife in a nearby stream, along with the fish in his garden pond.
Mr Beaumont told the Observer: “I’m very annoyed about it.
“Other properties down Moat Lane are affected and anybody who lives near the stream.
“The lady from the Environment Agency came round and said the ammonia levels are off the scale.”
Mr Beaumont added that it was the third such leak to happen since the start of the year.
The first leak happened in early January, with the second following about three weeks later.
A number of contractors have been working in the Claremont grounds and the surrounding area in a bid to fix the problem.
A Southern Water spokesman said: “We are doing all we can to minimise the impact of this burst pipe and are working closely with the Environment Agency.
“We have worked through the night setting up temporary pumps, using tankers to remove affected water and installing oxygenating jets to try to protect wildlife.
“A 26-metre section of the pipe has been replaced and a clean-up of the area is being arranged.”
A spokesperson from the Environment Agency confirmed that it was investigating the incident.
A spokesperson said: “Environment Agency officers are on site and still investigating the source of the sewage and are continuing to work with Southern Water”