Eeast Devon councillors have considered new research on coastal erosion by Plymoith University, estimating future rates of coastal erosion in the region over the next 100 years.

The research, which focuses on the eastern area of the district, is different from previous work on coastal erosion as it is for planning purposes only.

It maps a theoretical 'worst case' scenario of possible coastal erosion and includes an additional 10 metre buffer zone. It does not, however, take into account the protection that East Devon Beach Management Plan schemes currently in design will deliver.

The university research indicates that some parts of the coastline in East Devon will erode more quickly than had previously been estimated in the Shoreline Management Plan, while some will erode less than previously thought.

The study suggests that parts of the coastline at Seaton, areas either side of Branscombe and east of the River Sid at Sidmouth, may see more erosion than previously predicted.

In contrast, the coastline between Seaton and Lyme Regis, west of Seaton to the edge of Branscombe and much of the coast west of Branscombe up to the cliffs east of Sidmouth, may see less erosion.

East Devon District Council's strategic planning committee on Tuesday recommended that Cabinet consider the wider implications of the study, beyond the setting of planning policy, at their earliest opportunity - but with a note of caution that further work may need to be carried out to provide a fully informed paper.

Cllr Geoff Jung, portfolio holder for Coast, Country and Environment, said: "This is clearly an important piece of work to inform future planning policy and it is very much distinct from work that we are doing on coastal protection measures.

"We're making great progress in developing beach management plans and coastal protection works. These will be designed to slow the rate of erosion in Seaton and Sidmouth and hopefully prevent the worst case scenarios identified in this study from occurring."

The study showed areas in Seaton where more erosion is predicted in the new maps compared to the current shoreline management plan (SMP), including some properties accessed off Beer Road and the Highcliffs Close area, as well as two small areas either side of Branscombe mouth, and land in Sidmouth east of the River Sid, including properties accessed off Cliff Road, Beatlands Road, Southway, Laskeys Lane and Alma Road.

But areas that are predicted to experience less erosion than the SMP maps include the section of coast from Seaton to Lyme Regis, much of the coast west of Highcliffe close in Seaton, through Beer to the east of Branscombe mouth, and the majority of the coast from Branscombe mouth to the cliffs east of Sidmouth.

The study could be used to inform the policies of the new Local Plan, and could help to deliver coastal protection schemes. The main purpose of planning for coastal change is to identify the places most likely to be affected and to develop policies to reduce future risks to people and property and to help communities at risk prepare and plan for future risks.

Cllr Mike Howe said though that it was a hypothetical paper, as it was untested and didn't take into account the defences currently in the pipeline.

He said: "It does need more work, but it does need to be done quickly, and I am nervous about using an incomplete and untested piece of work for planning purposes. We need to push this to Cabinet but heed the warning and not change the principle."

Cllr Nick Hookway said that this was an issue the council had to face and they shouldn't look at it as a hypothetical, adding: "Maybe the algorithm is wrong but they'll get it right later on."

Cllr Olly Davey added: "Predictions are usually wrong, and the more specific they are, the more likely to be wrong, but sometimes you disregard that at your peril and we ignore this at our peril.

"This will be useful in highlighting some of the shortcomings in the current shoreline management plan around variations of rates of erosion in the cliffs."

Cllr Eleanor Rylance added: "The best case scenario is it doesn't get worse. We know global warming is happening and seas are rising, and the question is how much and the mitigation measures we take to limit CO2 emissions.

"I am not sure we should be proceeding with a best case scenario but a most likely scenario with the mapping, as with a best case, I am not sure we learn anything other than false reassurance."

But with the study predicting worsening rates of erosion to the east of Sidmouth, Richard Eley, president of the Sidmouth Chamber of Commerce, called for the Sidmouth Beach Management Plan (BMP) process be paused.

He said: "We should suspend the Sidmouth BMP and hold an evidence based review. How can we carry on if nothing is happened if we know this report? It may do the town a favour and gives a refresh of the whole process and reset the plan."

The beach management scheme for the town, consists of adding a new rock groyne on East Beach, importing new shingle onto Sidmouth Beach, and East Beach, and raising the existing splash wall along the rear of the promenade.

It aims to maintain the 1990s Sidmouth Coastal Defence Scheme Standard of Service and reduce the rate of beach and cliff erosion to the east of the River Sid, the scheme is now fully funded and is estimated to cost £8.7m – subject to the Environment Agency approving the submission of the council's Outline Business Case.