"Corridors" refers to planning controls such that new homes are not permitted within a certain distance of overhead power lines and vice versa.
The UK does not have corridors, on EMF or any other grounds. The only restriction close to a power line is to comply with the safety clearance distances to avoid flashover and with EMF exposure limits (but these normally do not pose any constraint in practice because for all except a very few low-clearance power lines the fields are below the exposure limits even directly underneath them).
The absence of corridors is not just by default or because no-one has thought about it. It is a definite national policy not to have corridors. The issue was analysed by the stakeholder group SAGE in its First Interim Assessment in 2007. Government responded through a Written Ministerial Statement in 2009, rejecting corridors, as they were not judged in the interests of the country to introduce:
"However SAGE's cost benefit analysis does not support the option of creating corridors around power lines on health grounds. The Government therefore considers this additional option to be disproportionate in the light of the evidence base on the potential health risks arising from exposure to ELF/EMF and has no plans to take forward this action." (para 4)
That 2009 announcement confirmed an approach that had previously been established, among other places, through Parliamentary Questions and Answers. For example, on 20 November 2007, Iain Wright, Undersecretary, DCLG answered a question from Mr Swire MP on building near power lines:
“No planning guidance on this subject has been issued to local authorities. At present, there are no planning restrictions on development close to power lines other than the need to observe safe clearance distances.”
We discuss some of the other issues about property and power lines here. See also the situation in the USA where power lines do have "corridors" (known there as "rights of way"). Although the UK does not have corridors, various distances from power lines are often talked about (60 m, 200 m, 600 m) and we discuss where each of these figures comes from.
