The main Westcountry railway line linking the region with the rest of the country and London has been shut after more than 1,000 tonnes of mud and slurry spilled onto the track.
The line closure, between Exeter and Newton Abbot, was ordered after one major landslip at Teignmouth was followed by a second, smaller, one and a further 13 described as "minor."
It comes as forecasters say more heavy rain is on the way this weekend with further unsettled weather expected next week.
A spokesman for Network Rail, which owns the railway infrastructure, said work was under way to clear and reopen the vital stretch of track.
"We are working round the clock to restore normal services as quickly as possible", he said.
Problems on the line became apparent on Wednesday night after concerns were raised about debris on the line up towards Exeter, which was quickly shut. It was then decided to close the down line.
The Network Rail spokesman said engineers inspected the area at first light yesterday and a team abseiled down the cliff to examine its structural integrity.
"They established that the mud and slurry was still on the move and it was continuing to be of concern.
"A contractor was called in to remove what is estimated at being between 1,000 and 1,500 tonnes of mud and slurry."
He said a further less serious mudslip had been identified further up the line towards Exeter. More than 13 minor landslides were also counted.
It is hoped that part of the line will be reopened later this afternoon and that it will be fully reopened on Saturday. In the meantime, a bus replacement service will operate.
A spokesman for the Met Office said further downpours were on the way for the Westcountry.
Today and tomorrow are likely to be dry and cold with a possibility of ice forming on roads where there is already standing water left over from the floods.
The spokesman said that Sunday could be another wet day: "There is more rain coming through for the South West."
"It will be heavy with about 20-25mm of rain expected to fall, which obviously is unhelpful for parts of the region where the ground is still saturated."
The spokesman said the rain would take most of the day to clear from the region.
However he added that a further spell of unsettled weather was on the cards for next week.
The forecast makes unwelcome news for a region still drying out after the floods of the last 10 days and where yesterday 13 flood warnings and 15 flood alerts remained in place.
Rail services which were hit by the worst of the weather are however getting back to normal.
Rail services on the Tarka Line from Exeter to Barnstaple will reopen on Monday despite flooding preventing scheduled major track works from going ahead.
The line has been closed between Crediton and Barnstaple since November 16, during which time Network Rail planned to replace a section of the line.
The works, which saw buses replace trains between Barnstaple and Crediton, were due to be completed by Monday, but heavy rain has seen work held up. The flooding damaged track and signalling and telecoms equipment at Cowley Bridge Junction between Exeter St Davids and Tiverton Parkway, meaning engineers were unable to transport equipment needed to complete the work. Network Rail has now agreed with train operators to complete the work with a four-day extension to the five-day blockade planned for next March.
Trains will resume running between Crediton and Barnstaple from Monday, although a replacement bus will run between Crediton and Exeter with signalling problems caused by floodwater still affecting Cowley Bridge junction.