Dacorum Borough Council spent £594,000 on CCTV to watch its residents last year, according to official figures.
Despite the pressure on council budgets, spending has risen by 35% since 2010, when the annual bill was £439,000.
The AA has accused councils of making "shed loads of money" from drivers caught by cameras and warned they have become dependent on the cash that fines bring in.
Across England, councils spent £78 million on cameras in 2017-18. Ministry of Housing, Communities and Local Government figures show that it is one area of spending that has gone up nationally since 2010.
The highest spender last year was Medway, with a CCTV cost of £900,000. There were five other councils which spent more than £1 million.
Councils use cameras to keep watch on roads and public spaces.
The AA says councils are using cameras to issue penalty charge notices (PCNs) and are dependent on the cash.
Luke Bosdet, of the AA's motoring policy unit, said: "Councils are making shed loads of money out of cameras and they are not re-investing it to make roads safer.
"There are certain yellow box junctions that catch people by the thousand. If so many people are being caught it shows that the road layout needs to be improved.
"Normally law-abiding drivers are being caught but councils won't do anything as they are pulling in the cash to prop up their other spending."
Civil liberties campaigners say councils are spending millions of pounds spying on residents despite cutting services in many other areas.
Big Brother Watch director Silkie Carlo said: “Research consistently shows that public cameras are ineffective at deterring, preventing or even solving crime, but that too much CCTV does curb citizens’ freedom.
“Surveillance is no substitute for policing, and this will prove to be a terrible waste of money.”
The Local Government Association had defended council spending on cameras.
The LGA's Simon Blackburn said: "CCTV plays a vital role in protecting the public by dissuading crime and antisocial behaviour, assisting police officers on the ground and supporting prosecutions for offences ranging from fly-tipping and traffic violations to acts of theft, robbery and serious violence.
“CCTV also reduces costs to the public purse as anyone caught committing an offence on camera is likely to plead guilty, saving time on trials."