South West Water has had its pollution fines slashed after blaming sewage in a busy harbour on irresponsible boat owners.

The company was originally fined £50,000 for allowing raw sewage into Salcombe Harbour and across a busy beach for a week at the height of the holiday season.

The fines were reduced to £15,000 on appeal at Exeter Crown Court after the water company argued that some of the detritus on the shoreline came from the thousands of boats that use the estuary in the summer.

Tourists reported illness after swimming and paddling at the polluted South Sands beach in Salcombe, where a corroded pipe caused a sewage leak. Children played in rock pools without them or their parents knowing that the water contained pollution 4,500 times the legal limit.

An Environment Agency officer on holiday with his family in the South Hams alerted colleagues after seeing sewage running down the side of the South Sands beach in August 2012.

SWW was alerted, but work did not start for three days and it was another four before the leak was stopped. The local council put up warning signs and staff from the water company and the EA patrolled the sands to stop children going into the affected areas.

Judge Jeremy Griggs was shown photographs of the beach packed with families on holiday and told that up to eight people staying in the nearby campsite had reported becoming ill.

The company also had a second, unrelated problem in

the centre of Salcombe, where worried lifeboat crewmen and the harbour master complained that children were playing in polluted water in the harbour.

That problem was caused by sewage seeping out of a damaged pipe into a surface water outfall that ran into the harbour at Chapel End. It was first reported on July 21, but engineers took more than a month to trace the source of the pollution. They discovered that, in addition to the leak, a domestic outfall had been routed incorrectly into the waste water system by a builder.

The company also blamed irresponsible boat owners pumping their waste straight into the harbour for much of the pollution.

SWW, which is based at Pennon House in Exeter, admitted two offences of discharging sewage illegally and was originally fined a total of £50,000, with £10,300, costs by magistrates at Torquay in November.

The company appealed to Exeter Crown Court and the fines were cut to £15,000, £10,000 for the leak at South Sands and £5,000 for the Chapel End pollution.

Judge Griggs, sitting with two lay magistrates, said: 'We're all satisfied that the level of fines was out of kilter with what was appropriate for this offending.

'The facts have been fully explained to us and the degree of culpability as not to justify the levels of the fines.

'At Chapel End the transfer of sewage from SWW's pipes was not capable of producing the detritus found on the shore.

'Analysis established that it was in part probably caused by a misconnection and also likely to have come from the thousands of boats that use the Salcombe estuary and discharge into it, contrary to procedures and advice.'

He added that the company should have tackled the South Sands pollution more promptly, but accepted that the emergency crew had an urgent call to a sewage leak a school.

Judith Constable, prosecuting, said the South Sands pollution was spotted by an officer on holiday on Monday, August 6, 2012. A small leak was traced to a pipe that had not been replaced during recent improvement work.

The SWW team arrived on August 9 after being told by EA officer Peter Ball that the public were swimming in the polluted water.

Miss Constable said: 'Mr Ball encouraged people on the beach not to go anywhere near the sewage. On August 10 the council was asked to put up notices, and signs were put up the next day.

'Mr Ball suggested SWW should sort things out more quickly. There was a concern for public health, given that this was August and was a popular holiday beach. It was considered whether the area needed to be cordoned off.

'The photographs show children playing near the rock pool at the bottom of the trickle of sewage. Mr Ball saw small children climbing on the rocks wearing flip-flops and saw that they'd been walking through sewage.

'The owner of the nearby campsite said his customers were upset by the pollution on the beach and there were six to eight complaints of illness after swimming in the sea. We can't say if they were caused by swimming, but there were concerns.'

She said the problem at Chapel End was unrelated and had been caused by sewage leaking from a damaged pipe into a neighbouring drain that emptied into the harbour. A lifeboat mechanic had made the first report and there were concerns that children were fishing or paddling in the water.

The problem was intermittent and was eventually traced in August after a further pollution incident, which led to complaints from the harbour master, sailors and tourists. Tests at both South Sands and Chapel End showed coliform bacteria levels of nine million per 100 millilitres. The approved level for bathing waters is 2,000.

She said SWW had 112 previous convictions, including one in which it was fined £24,000 for polluting Chapel End just seven weeks before the later leak.

Martin Meeke QC, defending, said the company had acted promptly over both problems and repaired them as soon as possible.

He said Chapel End was not a designated beach and was a dinghy-landing area, adding that part of the problem arose from discharges from visiting boats.

Efforts to repair both leaks, he said, had been hampered by problems gaining access to Salcombe at the height of the summer and the council's reluctance to close South Sands over an August weekend.

He said the company has more than 9,000 miles of sewers and tries to keep them all up to date. It has spent millions on Salcombe, but the South Sands leak was from a pipe that serves just four homes.

'This was not a major sewer,' he contended. 'To check the sewers every year would be to put our water rates through the roof.'

Mr Meeke said the sewage was carried out to sea by the tide and that South Sands had passed a water quality test taken half-way through the spill.

He said: 'These discharges are a drop in the ocean when the tide works its magic. It introduces a very emotional component to

talk about children in flip-flops walking through sewage.'

SWW accepted responsibility and apologised for the Chapel End and South Sands problems, but felt the fines imposed were disproportionate.

An SWW spokesman said after the hearing: 'At Salcombe Chapel a defective sewer enabled sewage to enter the surface water network at high tides. It took some time to identify its source due to the complexity of the drainage network. As soon as the sewer was located and we established that it was the responsibility of SWW, we fixed it within two days.

'At South Sands beach, sewage from four properties leaked onto the beach due to a defective sewer. We apologise for the delay in fixing the pipe and reassure our customers that we take reports of pollution very seriously.'