The state government has taken the extraordinary step of digging a deep trench hundreds of metres long to stop motorcycles and four-wheel-drives accessing a patch of crown land in the City of Armadale.

The land, bordered by Tonkin Highway, Armadale Road and Twelfth Road in Haynes, became a magnet for off-road vehicles after clay from the nearby Champion Lakes Regatta Centre was dumped there in the mid-2000s.

The trench has been ‘reasonably successful’. Credit:Hamish Hastie

The clay was dumped in mounds that created a challenging track for illegal thrillseekers and the land has caused headaches for residents ever since.

For more than a decade the WA Planning Commission has been battling with off-road vehicles by continually installing fences, only for them to be flattened within weeks.