One of the main roads into Lowestoft town centre will be closed for up to three weeks while emergency repairs are carried out.
London Road South will be closed from Mill Road to the A12 while repairs are carried out to the sewer underneath the road.
One lane of the road has been closed since the end of August after a problem with the sewer was reported.
And investigations this week have revealed that a manhole has dropped into the sewer, meaning that the road needs to be fully closed in order to enable the repair.
The closure means drivers will only be able to access Marine Parade, the main road which runs along the seafront, when travelling in a southbound direction across the Bascule Bridge.
News of the closure and the subsequent repercussions have prompted a backlash from a number of business owners who are based on London Road South.
Businesses along the busy road have expressed their concerns at having to go 21 days with very little passing trade, something which several stores rely upon for the majority of their income.
Ashley Powell, who is the manager at Mandarin Cycles, said: 'It's affecting us very badly; over the last couple days, our footfall of customers has basically dropped to nothing so we're not taking enough money.
'The signage is very poor as well and we may have to put up our own to attract customers.
'We also can't take deliveries because even a small lorry can't get to us.'
East Coast Cinema owner Michael Hansell added: 'So far the closure is providing difficulties for customers, who are finding it difficult getting to us. We'll be helping people out by giving them more time to get to the cinema.
'As bad as it sounds, we're used to one closure after another in Lowestoft and businesses can't do anything about it. We've just got to suck it up because this work has to be done.
'Local infrastructure in general needs sorting so that we can cope with closures like this.'
Anglian Water explains road closure
Anglian Water have highlighted that the closure allows crucial work to be done, emphasising that they are working round the clock to ensure normal service is resumed as soon as possible.
Simon Love, head of collection services for the company, said: 'This is an emergency road closure - as soon as we were able to assess the full extent of the problem we shut both lanes to ensure public safety.
'It's a complicated job but we are working as many hours as possible – from dawn to dusk and throughout the weekend – to get this job done and the road opened as quick as we can.
'We aim to keep people in the area informed as much as possible – we will be sending letters to local residents and businesses, we will be updating our In Your Area webpage, posting on social media and we'll have digital signs up giving live updates.
'Please be rest assured we are working as hard as we can to get this fixed and traffic moving again.'
Residents and motorists react to closure on social media
Local people have been taking to Facebook to convey their thoughts on the London Road South closure and its impact.
Richard Carson was pessimistic about its effect on the fortunes of Lowestoft, stating 'Another reason why nobody will bother travelling into the already struggling town centre.'
Elsewhere, Carolyn Ann Wright called the situation a 'nightmare', whilst Adam Sutton said 'this is going to affect everybody in Lowestoft one way or another, home life and businesses.'
Some highlighted the need of the work. Victoria Schofield said: 'They can't win can they? They delayed it till after the summer holidays to avoid inconveniencing people and it needs doing. They aren't doing it for fun. Leave a bit earlier or choose another route.'
Lynda Byford was in agreement, voicing that the work 'has to be done sometime', but added 'pity there isn't another alternative route for people to use.'
How will this road closure affect you? Email lowestoft.journal@archant.co.uk
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