Street lights are being switched off around the country as part of trials to help save energy and money. But will the streets be any less safe?
Saving money is something local authorities have become old hands at. But councils are not the only ones being kept in the dark by the latest initiative.
With energy costs soaring, some councils are experimenting with turning off some street lights. It's a plan with the bonus that less lighting means a cut in harmful CO2 emissions - and town halls are obliged by law to reduce waste.
Residents, however, aren't all applauding the move. Some have been surprised to see the familiar orange glow extinguished after midnight. On some rural roads, the lights no longer come on at all.
Despite several councils being involved, the trials are ad hoc - each is doing it differently.
- Buckinghamshire has selected sites that are "low-risk" and has added solar road studs, extra signs and road markings. The first phase of its three-year trial involves switching off 287 street lights. 1,700 more will follow saving the council £100,000 a year and 590 tonnes of CO2
- Gloucestershire County Council says it will be turning off 36% of its lighting part-time, but not on main traffic routes or areas of high crime
- Essex is carrying out "part-night lighting" trials in Maldon District and in Uttlesford
- Hampshire and Hertfordshire are also running trials
It's easy to see how turning off street lights might be bad for safety, but Buckinghamshire, for one, refutes the suggestion.
Gas street lights were first introduced to the UK in 1807
"In seven sites monitored there were a total of seven collisions between August and December 2006 when lights were on, and only three in total between August and December 2007 when lights were off," says spokeswoman Sheila MacDonald.
Its pilot was drawn up with the help of safety officers, police and local residents, she says, and sites have been selected "which are low risk".
The AA, however, remains unconvinced by such assurances, insisting that good lighting improves safety for all road users.
"Turning off street lights to save money or CO2 may backfire in terms of increased accidents and crime", says AA president Edmund King. "Local authorities concerned at the environmental impact should consider more environmentally-friendly lighting rather than putting us all in the dark."
As well as road safety, there are concerns about the effect on crime of turning lights off. But the relationship between crime and street lighting is not as obvious as might be thought.
A Home Office study from 1991 found lighting was more likely to have a positive impact on the public's fear of crime, rather than on the incidence of crime itself.
Commissioned at a time when spending on lighting was being increased, in the hope of combating rising crime, the report's author, Dr Malcolm Ramsey, observed that the rise in crime in the period after World War II coincided with major improvements in street lighting.
He said the confidence in the effect of lighting on crime "owes much to the initiative of the lighting industry."
"Better lighting by itself has very little impact on crime. There are some local blackspots where improved lighting may have a modest impact on crime and perhaps a slightly larger one on incivilities," he concluded.
But while several of the councils which spoke to BBC News emphasised their consultations with the police, the Police Superintendants' Association has been critical of the "switch-off" trials.
It insists good street lighting deters crime and reduces accidents, and is concerned that environmental issues could be put before public safety.
Yet Essex says local police have given its trial the nod.
'Lights Out London' was a one-hour local experiment in 2007
"The evidence from working groups set up to study the scheme, including the police, seems to suggest no adverse effects in terms of antisocial behaviour, repeating positive evidence from other schemes around the country," says the council.
However, the council has issued a list of exemptions to the part-lighting trial, such as security premises and remote alleys linking residential streets. It has emphasised the scheme is operating only in rural residential areas. Street lights remain on all night in town centres and other busy places, and along main roads.
In Devon and Cornwall, where a similar switch-off scheme is being considered, police say it is a matter for the local authorities. But they would expect to be consulted.
"The research into the impact of street lighting on crime is contradictory," says Superintendent Steve Swani, "but what is clear is street lighting makes people feel safer, which is a very important factor to consider."
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