POLICE have slammed the “irresponsible” actions of locals who tip over unattended boats and trailers cluttering their streets.

At least two trailers with dinghies were tipped on their sides on busy streets within a week in a move believed to be sparked by a lack of parking spaces.

media_camera A trailer tipped on its side at Pittwater Road Mona Vale. Picture: Bill Ditmarsch

These are the latest in a string of acts of vandalism, including tyres being slashed on 20 trailers on a Manly Vale street last year.

And a 4.8m Huntsman half-cabin boat with a 115hp Evinrude outboard motor disappeared from Pittwater Rd, North Manly, after a sign was attached to it saying it was free.

Residents sick of a boat and a trailer sitting in their street emblazoned them with signs saying “move your boat” and “free boat”. Both boat and trailer were later stolen.

Police are concerned about the escalation in tactics and are urging boat owners to report damage.

Northern Beaches duty officer Insp Graeme Pickering called the latest actions “irresponsible”.

“It is definitely malicious damage and it is certainly an irresponsible action that could possibly cause a collision,” he said. “There is a tabletop ute that has had to cross double white lines to get around it.”

media_camera Martin Skrlik with daughter Amelia, 2, and Michael Chan next to a flat tyre on their boat trailer and a caravan that is parked along Kenneth Road at Manly Vale. Picture: Troy Snook

Bill Ditmarsch photographed the tipped-over boat, which he said impeded traffic on Pittwater Rd, Mona Vale, last week.

“We have a big problem in this area. There are trailers all over the place,” Mr Ditmarsch said.

“It is becoming just such an awful pest, it is getting worse. In my street, four years ago there were only three trailers parked, but every few months it just gets worse.”

He said another trailer was tipped over less than 1km away in front of Pittwater High School.

Insp Pickering said the person responsible for tipping the trailers over could be charged if found.

As of July 1 last year, Northern Beaches Council has had the ability to opt in to take impounding action against boat trailers parked for more than 28 days.

The council must provide 15 days notice before impounding a trailer.

Acting deputy general manager David Kerr said the council prioritises parking controls in high pedestrian areas, especially around schools.

media_camera Slashed tyres on boat trailers parked along Kenneth Rd at Manly Vale last year. Picture: Troy Snook.

“Council has issued formal notices to the registered owners of a number of boat trailers in the area north of the Narrabeen Bridge,” he said. “Given the proximity of Pittwater High School to the Rowland Reserve boat launching ramp this area is a priority.”

But Mr Ditmarsch said stronger regulations had to be put in place to stop nonresidents parking unattached trailers on the street.

Pittwater state Liberal MP Rob Stokes believed recent issues were partly caused by residents not being aware of the recent law changes.

“My advice would be to contact the council, which has powers it did not in the past,” he said.

“I would not condone taking matters into your own hands. It creates increased risk of conflict and can create serious traffic hazards for vehicles.”

While he acknowledged issues with trailers, he said the new laws struck the right balance.