Young rowers arrived at their Horowhenua club to find all but two of their boats smashed and strewn around the clubhouse.

It comes in the middle of what Horowhenua Rowing Club members describe as mounting abuse and threats from Maori activists over ownership of Lake Horowhenua, near Levin.

Horowhenua Mayor Brendan Duffy described it as a "lowest-level frenzied attack", which he believed had been carried out by just a few individuals who he claimed had been threatening to do this for a while.

Club treasurer Jo Mason said members discovered the damage when they opened for training at 8am on Saturday. A square opening had been cut out of the building's iron wall and there were numerous holes smashed into all but two of the boats.

"Twenty-five boats were pulled off the racks and had holes stabbed through the bottoms of them," she said.

Mrs Mason said police counted 75 holes in total, and she estimated they could cost up to $100,000 to repair.

The cash-strapped club would have to pay to have all the boats transported to Lake Karapiro in Waikato for the work to be done, which would mean the boats would be out of action for much of the coming regatta season.

Insurance assessors are due at the club today, and Mrs Mason could not guarantee the policy would cover the full costs.

Constable Lionel Currie, of Levin, last night confirmed police were investigating the incident. No-one had been arrested.

The vandalism was the latest in a string of incidents around the lake, stemming from about 2008, when squatters occupied the neighbouring Horowhenua Sailing Club as part of a dispute over lake ownership.

Mrs Mason said the club had been harassed by "Maori activists trying to evict us" for years, but she thought they had become more aggressive in the past few weeks.

The abuse had become so bad that some parents were reluctant to send their children to training.

It was a "small, dedicated club" of 40 members of all ages, and was one of the poorest in the country.

"We work really hard to maintain our equipment," Mrs Mason said. "We can't afford to be replacing our boats. We're all crying because we love these boats and we love this club."

The club had a good relationship with the local Muaupoko iwi, who had conducted a blessing ceremony since the break-in, she said.

"We respect that we're on Maori land and we do everything we can to accommodate”, but she believed that certain others have just really “got it in for us".

Club member Michael Fryer, 17, said the attack on the boats was a "childish" act that had thwarted his season's training.

The local youth council chairman said the $6000 boat he used was ruined.

"I'm sad. I do a lot of work for the community, and I get paid back like this.

"If people have got something to talk about, just come talk to me, don't ruin my boat."

Mr Duffy said the vandalism served no purpose and he wanted to send a "powerful message that this community has had enough".

He would work with iwi and lake representatives to come up with a plan to deal with the issues, while police conducted any criminal investigation. Fairfax NZ

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