The first time Joel Pilgrim took a client out on the waves could have been the end of his career as a mental health occupational therapist.

Also a surfer with 28 years' experience, lifeguard and surf coach, he was trying to get through to a young patient by asking him what he wanted to do. He wanted to surf.

"I could have had my head on the chopping block, let's just put it that way," Mr Pilgrim says of the unapproved activity.

"It was a clinical risk that I justified with clinical reasoning."

It paid off.

"He was just this completely different person when he moved down that guard and moved away from that formal, clinical setting," Mr Pilgrim says. "Shared with me things he had never shared before."

The experience propelled Mr Pilgrim to co-found Waves of Wellness, a surf therapy organisation which has, to date, treated more than 3200 people across 10 locations Australia-wide.

Combining surf instruction with professional therapy, WOW employs psychologists, occupational therapists and social workers who usually operate in a normal hospital setting but are also learn-to-surf instructors.

"We call them our unicorns because they're really hard to find but they're very special and do create a lot of magic," Mr Pilgrim says.

"Someone will come down to the beach and they will say there is no 'effing' way I'm going to access a mental health service or an inpatient unit ... but I'll go surfing.

"So, we're getting people in hook line and sinker and giving them this wealth of knowledge and ways to cope and manage their mental health."

The therapists, or facilitators, offer a range of sessions that cover a variety of engagement - including cognitive behavioural therapy and acceptance and commitment therapy - that are traditional methods in a hospital setting.

They have programs specifically for high-functioning men whose mental health can otherwise "fall through the cracks", war veterans, emergency services workers, domestic violence and women's trauma groups, youth at risk and youth off the streets programs, programs for Aboriginal and First Nations people and people in the LGBT community.

An Australian-first study into the effectiveness surf therapy on at risk youths funded by WOW found it could "increase self-esteem, resilience, and social connection, and reduce depressive symptoms among Australian adolescents".

Nine participants of the WOW Bondi program self-reported their experience before, during and after therapy, with results suggesting the heightened sensory experience could be "meaningful and life-enhancing".

"Quantitative findings provided evidence of positive change in self-esteem, resilience, social connectedness and depressive symptoms after eight weeks of surf therapy," the report says.

Therapy begins with an 'expression session' with 10 to 15 people talking in a circle on the sand on their boards before they take to the water.

"Out there in the ocean, there is this equaliser," Mr Pilgrim explains.

"When you get into the ocean and take all your clothes off and get into a wetsuit, you can't tell who is who. You can't tell who's a CEO and who's sleeping rough. All the labels and titles and everything that people pin to themselves are removed.

"They'll be waiting for a wave and the facilitators will say 'what was that like for you' or 'what you mentioned in the group before, can I ask you more about that'.

"People are just people out there, having beautiful conversations."

Edith Cowan University clinical psychologist Mary Brennan agrees there is evidence of surf therapy's effectiveness.

"Research tells us spending time in blue spaces, or areas where visible bodies of water such as ocean or lakes are present, can assist with lowering stress and anxiety levels," she tells AAP.

"Additionally, improving active relationships with blue and green spaces can enhance emotional wellbeing and social connectedness."

But in general, 'alternative' or 'complementary' treatments like surf therapy should be considered supportive, rather than replacing foundational, evidence-based therapeutic techniques.

"Maybe alternative therapeutic approaches have a place in prompting us to reconsider our relationship with ourselves and others, our relationship with our work and workplaces, our lived environments and the space beyond that," she says.

WOW's sessions, which follow a similar program as they might in a hospital, often conclude with meditation out on the water, where participants are encouraged to lie back, eyes closed, with their boards arranged in a 'hashtag' shape.

One facilitator leads the meditation, the other moves the boards through the water.

"Connecting mental ill health and surfing means we're pulling mental ill health out of the darkness and making it a topic that can easily be approached and talked about rather than hidden away," Mr Pilgrim says.

"We're removing the stigma and allowing people to come and access this type of support and therapy which they would never ever have accessed otherwise."

This is no hippy dippy technique. Having once worked in one of the UK's highest profile psychiatric hospitals, Broadmoor, Mr Pilgrim says the therapy has had great impact with some of his most unwell patients.

"One guy in Newcastle said something I'll never forget. He said 'These are the only two hours that ... I don't hear the voices in my head," Mr Pilgrim says.

The schizophrenia patient had peace from the overwhelming sensory stimuli he lived with just by being out on the water.

"For us, surf therapy is using surfing as a conduit to create positive change in someone's life regarding mental health. We're teaching mental health literacy," Mr Pilgrim says.

"We call it 'health by stealth'."

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