Hundreds of Canberra home owners could be overstepping their title boundary and squatting on their neighbour's property, risking a loss of land and a territorial dispute if found out, a surveyor has warned.
The warning by veteran surveyor Peter Shaw comes as a property investor called for a change to ACT laws after neighbours dug up a section of his driveway that had for decades encroached upon the block next door.
Paul Cleary, owner of the infringing concrete driveway in Ainslie, part of a block laid out in 1927, said adjoining landowners had without notice sent contractors to cut up a section of the vehicle access on March 28 last year, in the process cutting the property's phone line for several weeks.
"The reason for this land grab became clear later in the year when they applied to have a massive extension that would make the house close to the maximum percentage of the land area," he said.
"The law should be brought into line with the Australian states so that other Canberra residents don’t have to go through such distressing experiences."
All states allow the exclusive possession of land - without permission of the owners - to lead to a shift in title after a set period and subject to often strict conditions. A 15-year wait applies for claims against private owners in Victoria and South Australia, and 12 years elsewhere.
Mr Cleary does not dispute his driveway and part of the back of his property, including an 0.5 metre slice of his garage, did cut across the surveyed boundary of the block, but said his neighbours' action on the driveway occurred without warning and before any ruling by the ACT Civil and Administrative Tribunal. He said the neighbours had told him in December 2012 that they wanted to move the physical boundary.
Mr Shaw, principal of Kingston surveyor P.J. Shaw & Associates, said the case was one of the worst boundary disputes he had seen, although he had come across 50 smaller problems - and had possibly 20 of those agitated owners on the phone - in his three decades of business in the region.
"Quantifying it is difficult, but many hundreds of ACT home owners could possibly be affected."
Most, he said, were the result of fences being put in the wrong spot, with the chances of detection reduced compared with 30 years ago as banks now demanded fewer block surveys before granting mortgages.
He said as recently as last week he found a 1.2-metre fence error after completing a contour plan for a greenfields block in Gungahlin.
Mr Shaw said the worst ACT fence mistake he had heard of involved a couple in Gilmore who The Canberra Times reported in 2004 were forced to move a dividing fence up to 4.4 metres, leaving them an estimated $50,000 out of pocket due to landscaping improvements made before the neighbours – looking to extend – discovered the error.
LANDdata managing partner David Sloan, a surveyor in Canberra for 22 years, said he had only ever known of a few minor cases where fences had been constructed out of position.
A spokeswoman for Planning Minister Mick Gentleman said there would be relatively few incursions of neighbouring property similar to Mr Cleary's, but there were "likely to be considerably more minor encroachments" and recommended all land be surveyed before purchase to address any discrepancies.
Limits on unilateral action to repossess could apply.
"As a matter of general principle, a landowner is entitled to undertake lawful activities on the land they own," the spokeswoman said. "The extent to which this would permit interference with structures built by a neighbour is a matter that depends on the circumstances and the operation of relevant laws, such as the Common Boundaries Act 1981."
The spokeswoman indicated adverse possession could not operate in the ACT because of the Torrens title system, although the principle co-exists in most other states with the government-guaranteed title arrangements.
An owner involved in last year's dispute with Mr Cleary declined to comment.