Public health fears have been raised in the Westcountry after reports of almost 300 cases of sewers leaking into homes, rivers and beaches – in just a fortnight.
Environmental campaigners called on authorities to clean-up dirty waterways, footpaths and properties, and warned tourist hotspots will be shunned by visitors unless urgent action is taken.
South West Water blamed the 290 reports it has received since Christmas Eve – many in Exeter, Plymouth, Torquay, Newton Abbot and Brixham – on exceptionally high December rainfall triggering overflow systems.
But Hugo Tagholm, executive director of pressure group Surfers for Sewage, said more needed to be done.
"This is a problem and it does need fixing. Even when there is light rain or no rain at all, sewage can pollute our beaches and rivers."
But he added that recent heavy rain had had a "dramatic impact" on sewer-related incidents.
"This is a public health issue. We need to improve infrastructure and provide people with more information about the problems," he said. "It is vitally important to protect our coastline and beautiful beaches which are a big part of the tourism industry in the South West."
Figures provided by South West Water for Devon and Cornwall revealed 54 of the sewer leaks were internal – where the system backs up through the drains inside properties.
The other 236 reports during the fortnight were external, with sewage leaking into streams, rivers and the sea.
In the Devon town of Modbury residents reported a "massive discharge" of raw sewage into a stream on December 22.
Following long-term sewage and flooding problems in the town, a meeting was held in October chaired by MP Gary Streeter and attended by South West Water, the Environment Agency (EA) and councils.
But resident Joanna Owen claimed stream banks and footpaths were again covered with sewage, and no signs in place to warn the public.
She said: "The stream is covered in faeces and loo paper. The water is black and grey from one source and brown from another.
"We are a civilised country putting up with a third world problem. People walk through on a daily basis with dogs and children. How can anyone allow people to walk through sewage? It is a health hazard and should not be happening. The footpath needs a proper clean-up."
She said nothing had been done apart from the cancellation of a voluntary clean-up of litter due to the waterway being a health hazard.
Alison Butts, of South West Water, said: "Our staff have been working round the clock to deal with the challenges caused by the extremely heavy rain and flooding over the festive period. The sheer volume of surface water entering the sewerage network has overloaded the system in some places.
"However, the operation of combined sewer overflows in the sewerage system has protected hundreds of families from the misery of their homes being flooded.
"We do understand that sewer flooding is very distressing. We will work with other agencies in communities where there has been flooding to alleviate problems."
The EA's Paul Gainey said: "Any reports of raw sewage entering a water course we would consider a priority.
We would work with South West Water and the local authority to look into the problem.
"With all the heavy rain and flooding you will get incidents of polluted water, which in some cases will have been caused by surface run-off from fields."