Sewer gaff that costs £1million to clear up.

The concrete blocked the sewer so solidly it could not be removed, so a 50-metre tunnel had to be dug six metres underground to bypass the damage.

While that was happening, pumps were installed to keep the system flowing.

But heavy rain overwhelmed the pumps and homes and shops were flooded.

Residents and traders in Sackville Road have lived with the stench for months.

Sludge trucks were brought in for a nightly clearance operation.

This week residents could breathe again: Southern Water said the repair had been completed ... at a price running into seven figures.

The work brought to an end an embarrassing episode in the building of the De La Warr Heights luxury apartment block at the southern end of Sackville Road.

Southern Water blamed contractors working on the complex for accidentally pouring concrete down the connections which entered the sewer from the buildings demolished to make way for the development.

The tunnel operation was described as complex, similar to working in a mine.

Jim MacIntyre, Southern Water area networks manager, said: "We would like to thank residents for their patience during this emergency repair which has been a major engineering challenge.

"We apologise to the residents who were affected by the sewer flooding during the exceptionally heavy rainfall. For the remainder of the works we increased our inspections of the pumps and improved the alarm system in order to prevent a recurrence."

Southern Water say they will be seeking to recoup the cost of the project from "those responsible for the damage."

Robin and Jan Powell of H and H Confectionery totalled losses of over 551 in the flooding. They have applied to Southern Water for compensation.

Jan said: "Southern Water said they will pay us for our losses but it was awful. Things like marzipan and fudge couldn't be refrozen. They have said we will be fully compensated but that remains to be seen."

"It is such a shame that this had to happen, rather than them passing the buck to start with."

Robin added: "We had dehumidifiers and fans down here for 18 days each running 24/7. Much of the claim is from the electricity on those. We were swimming.

"But I do want it to be said that when Southern Water found out about the problem the help we had was instant. Within in an hour and a half they got in Rainbow International (clean-up contractors) and they did a great job."

Nick Wells, of C Wells and Sons, whose basement regularly flooded while the work was being carried out, said: "Time will tell. We had a similar problem years ago, but that was fixed and only came back with this building work.

"I hope they are right that it is fixed, but we will have to wait and see."