The SNP is accused of being “all at sea” over flood defence schemes, as projects at Broughty Ferry, Comrie and Arbroath are set to bust their initial budgets.
The Scottish Government identified a total of 42 flood protection schemes for delivery between 2015 and 2021.
But it can be revealed only six of the schemes are currently under construction and a further 25 are still at the development stage.
Figures revealed through parliamentary questions also show cost overruns in almost every project, with the Broughty Ferry scheme rising from an initial cost of £10 million to an estimated final cost of £16.3m.
The flood prevention scheme is expected to protect 450 properties in the seaside town and will transform the appearance of the coastline.
Of the planned flood schemes where work is yet to start, Arbroath has risen from an estimated cost of £11.4m to £13.5m.
The project at Comrie, near Crieff, has risen from an initial cost of £15.7m to a final estimated cost of £28.4m.
‘Costs going through the roof’
Beatrice Wishart, Scottish Liberal Democrat rural affairs spokeswoman, said the figures show the “Scottish Government is all at sea when it comes to building up our flood defences”.
The Shetland MSP added: “From Aberdeenshire to the Borders, communities are facing the devastating prospect of floods, while Storm Arwen showed just how vulnerable Scotland has become to major weather events.
“When it comes to flood defences, prevention is always better than having to repair after the damage is done.
“Our climate has changed dramatically in the past few years so simply bobbing along is no longer an option in the face of more extreme weather.
“Not only are more than half of their prospective projects unfinished, the costs are also going through the roof.
“The Scottish Government needs to scale up flood protection measures and make sure that local authorities have the resources they need to protect our communities and ensure that these projects are delivered.”
Costs ‘revised over time’
Final scheme costs are the latest estimates provided by local authorities.
The parliamentary answer by Environment Secretary Mairi McAllan said “differences between these latest estimates and initial cost estimates arise because flood protection schemes are put forward for prioritisation at various stages of their development”.
Costs are revised over time as designs are finalised and more detailed investigations are carried out of the site.
Outcomes from community engagement and changes to price and supply of materials may also require revisions to cost estimates.
It is estimated that 284,000 homes and premises are already at risk of flooding in Scotland, with an additional 110,000 properties at risk by 2080.
Flood risk management
A Scottish Government spokesman said: “Local authorities are responsible for commissioning and delivering flood protection schemes which, like all infrastructure projects, can take many years to progress from option appraisal to completion.
“New flood protection schemes impact on individuals, communities and the environment, and require careful and thorough planning to ensure that they reasonably balance the interests of the whole community.
“Since 2007, a minimum of £42 million per year has been distributed from the Scottish Government to Local Authorities to support investment in flood protection schemes.
“In 2020 we committed to go even further, investing an extra £150 million in flood risk management over the next five years which represents a 70% increase in the flooding budget.
“We also provide £195,000 annually to support the Scottish Flood Forum to build flood resilience within communities.”
Dundee City Council were approached for comment.