Flooding and water emergencies caused 10 deaths and injuries in Buckinghamshire last year, new Home Office figures show.
The Environment Agency said climate change is likely to mean “more frequent, intense bouts of flooding” will hit the UK.
Between April 2017 and March 2018, there were 10 deaths or injuries in incidents where firefighters were called to flooding or water emergencies. The previous year in Buckinghamshire there were five.
Over the same period, the Buckinghamshire and Milton Keynes Fire and Rescue Service rescued people during 12 flooding or water incidents, a 20% increase on 2016-17.
The crews took part in two evacuations involving up to five people and one of up to 20 people.
The data showed the most frequent type of incident firefighters attended was making sites safe from flooding. There were 199 in 2017-18, as well as 30 occasions where crews offered advice and 13 call outs for pumping water.
There were 268 call outs in total in 2017-18, up from 241 in the previous year.
Death and injuries due to flooding and water incidents increased in nearly half of England's 43 fire and rescue services.
Mark Wrack, Fire Brigades Union general secretary, said the figures show the challenges firefighters face in responding to these rescues, despite cuts to staff and resources.
Mr Wrack said: “These figures reveal the immense value of the work of firefighters, and also the scale of the challenge they face with increased cuts to their numbers.
“Firefighters have always rescued people during floods and will continue to do so, but the service needs to be properly resourced, with sufficient staff to deal with more frequent flooding and the best equipment to deal with the hazards.
“For over a decade, we have campaigned for firefighters in England to have a statutory duty to respond to flooding, as they do in Scotland, Wales, and Northern Ireland. This would put future flood emergency response on a solid statutory footing and improve resilience in the face of the increased risk of flooding.”
A Home Office spokesman said the Government is “confident” that fire and rescue services have the resources they need to do their work, and they will receive £2.3 billion in funding over the current financial year.
Caroline Douglass, of the Environment Agency, said: “Climate change is likely to mean more frequent, intense bouts of flooding, and knowing what to do in a flood could save your life.
“We urge people, wherever they live, to take some simple steps such as checking their flood risk online, reading the Prepare Act Survive plan to protect themselves and their homes."