For illustration purposes. Can't say I know of any PMs who have earned this exact figure (a few that started/sold their own business probably earned over this averaged out over the years - but couldn't exactly call that purely PM work to be fair), but I know a few not far off (130/180k with 10+ years - construction industry).
Depending on the conditions/hours/locations/etc your willing to agree too the salary swings wildly. Some recent graduates (little to no experience, still assisting and learning the ropes) are grossing well over 60k in certain companies.
Don't have any personal knowledge of the south west area though, so not too relevant to the OP. Think they require something a little more area specific. Just hoped to point out depending on the risks, the time commitments, the pressure and the level of hands on work its VERY tough to put an average wage on the job. A project is a project because its unique, it all depends on what is needed for the project/company in question.