It has emerged the NSW Government signed contracts worth more than $2.6 million for shark barriers that were never installed, a day after a teenaged surfer survived a shark attack on the far north coast.

Cooper's injured leg after he was bitten by a shark. ( Supplied: Seven Network )

One of the barriers, worth $1.3 million, was due to be installed at Ballina's Lighthouse Beach, where 17-year-old surfer Cooper Allen was mauled by a shark on Monday.

The teenager is still recovering in Lismore Base Hospital following the attack in which he was bitten on the upper-thigh.

However, attempts to install the barrier were abandoned in August, due to the weather and tidal conditions at the beach.

Another barrier at nearby Lennox Head, valued at $1.33 million, was scrapped after the design was deemed inappropriate for the beach.

The contracts, with suppliers Eco Shark Barrier and Global Marine Enclosures, state they will provide "design, construction, transportation, installation, maintenance and removal" of the shark barriers.

Opposition primary industries spokesman Mick Veitch called on the Minister, Niall Blair, to explain the cost to taxpayers.

"The people of NSW need to know exactly how much has been spent to date on the failed eco-barriers," Mr Veitch said.

"More importantly, were there exit fees or breach of contract fees because of the failure?"

Mr Veitch said the Government should have known the eco-barriers were an unsuitable solution.

"If they'd spoken to the locals, they'd know there was a great risk with these eco-barriers."

"[It's] because of the tidal action of that part of the coastline and the waves."

Primary Industries Minister Niall Blair defended the cost and said some of the $2.6 million could be spent on other measures to prevent shark attacks.

"We've had a go at putting these in the water, they haven't worked," Mr Blair said.

"The first stage of the trial has met those hurdles.

"We'll now look at redirecting the funds that were allocated for the rest of the trial on those barriers into other mitigation strategies."

The attack on Monday was the fourth serious shark attack along the one-kilometre stretch of beach in less than two years.

Cooper Allen, 17, was bitten by what is believed to have been a great white off Ballina. ( Supplied: SharkSmart )

Surfers call for shark cull on north coast

Le-Ba Boardriders president Don Munro said the NSW Government was not doing enough to protect north coast surfers.

"We want drum lines in, we want the commercial fisherman locally to be given back their licence to manage and remove a shark permanently," he said.

Cooper Allen is recovering in hospital after he was attacked by a shark on Monday ( (Facebook) )

He said, while "wholesale slaughter" was not the answer, but that there should be some sort of local cull.

"We're going to just continue to see more attacks and they'll end up, through sheer weight of the percentages ... that we're going to have fatal ones.

Surf Life Saving NSW announced that Ballina's Lighthouse, Sharpes and Shelly beaches had reopened on Tuesday.

Seven Mile, Lennox Head and South Ballina beaches have also re-opened.

The beaches were closed for 24 hours following the attack on Monday.

"Surf lifesaving assets were on the water from 8am conducting a roving patrol along the coastline as part of the comprehensive process of reopening local beaches," a statement from Surf Life Saving NSW said.

"After a meeting involving the NSW Department of Primary Industries, local council representatives, NSW Police and lifeguards, the decision was made to reopen the beaches with the exception of Lennox Head.

"Lifeguards will continue to monitor the beaches for any shark activity, with the safety of the public remaining the number one priority."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 9 seconds 1 m 9 s Mini ripper in flight ( ABC North Coast: Samantha Turnbull )

A statement from Ballina Council said the Department of Primary Industries had doubled aerial patrols and was deploying smart drumlines.

A trial of a shark-spotting drone, known as a 'mini ripper', resumed off Ballina's Lighthouse Beach on Tuesday.

Little Ripper Rescue chief operations officer Ben Trollope said the mini ripper drone was fitted with a loud speaker, sirens, SOS lights and a flotation device with a shark shield.

He said no sharks were spotted on Tuesday.

"This morning there was quite a large bait ball of the coast, quite a few dolphins coming through, and a couple of whales passing as well," Mr Trollope said.

"[The goal] is to be able to give people in the water early warning, rather than having no idea that the animal is actually there."

He said the drones would spend about 25 minutes of every hour in the air throughout the day.

Cooper Allen, who was attacked by a shark on Monday, is a keen surfer. ( Supplied: Facebook )

Queensland Premier offers to build shark nets

Queensland's Premier Annastacia Palaszczuk has offered to help extend the state's shark nets into Northern NSW in the wake of the attack.

Ms Palaszczuk said she would contact her southern counterpart on Tuesday to make the offer.

"We have the technology, we have the skills," Ms Palaszczuk said.

"I am prepared to work with the NSW Government to extend our drum lines and shark nets down the northern NSW beaches to protect people."

However, it is understood that NSW would be expected to pay for the lines.

Ballina Mayor David Wright said increasing surveillance was a better idea than the mesh used to protect Sydney and the Gold Coast.

"Because it kills so many dolphins and turtles, I just don't think the local community - Seabird Rescue and all those things - that they would countenance it," he said.

"We know it's a risk if you go in the water. There are other means, and I think shark spotters or whatever."