This warning comes from ALARM - The National Forum for Risk Management in the Public Sector - which is the UK's leading public sector risk management organisation representing councils, schools, hospitals, police fire and rescue services and many more.
ALARM believes that such a hike in insurance premiums could come as a major blow to public sector bodies, as such costs are likely to have been put aside for other services across the board, unless specific provision was made in anticipation of such increased costs.
Climate change has long been a concern for the public sector, as it brings many practical implications, particularly in the case of flooding, which can cause widespread damage and disruption.
ALARM believes that the only way to combat the expected rise, is to manage out the risk of flooding and its subsequent damage, in the first place.
Various measures can be taken to raise awareness of the risk of flooding, and the actions that can be taken to prevent it causing major losses, including education, 'floodlines' and a ready supply of sandbags.
ALARM chairman Bob Cope said: 'Public sector organisations must not bury their heads in the sand and begin to introduce robust plans to deal with the risk of flooding.
'Insurance premiums are on the increase, and taking prompt action to combat the risks associated with climate change must be taken now, before further increases cripple public sector spending.
'Flooding is one of many natural risks and whilst it cannot be completely eliminated it can be prepared for. By adopting int egrated flood risk assessment, it is now possible to utilise specific data sources to directly relate most weather and other environmental risks to a particular location, whether this be local, regional or on a national scale.
'Digital mapping and scenario modelling can also be developed with integrated data sets to greatly improve flood risk assessment and contingency planning.'