Dr Smith told the Nelson Mail he would meet Department of Conservation officials today following concerns about a lack of signs warning of the dangers at the waterfalls, south of Murchison.
"Two accidents in one week is two too many," he said.
"You can never save people from foolish judgment, but we have a duty to ensure we do everything possible to prevent these types of tragedies."
A Christchurch man drowned on Saturday evening after jumping off the 11-metre falls in a bid to save a friend who had been sucked over them.
The death followed the rescue of a Belgian tourist last Wednesday.
He had climbed over a barrier to take photographs of the falls, but slipped and fell four metres on to a ledge. He was saved by three Australian kayakers who managed to pull him to safety.
The victim on Saturday was one of three men from Canterbury who had stopped at the falls on their way to Nelson, police said.
The group climbed over the barrier fence, and the man went for a paddle in the pools above the falls about 6pm, despite his friends trying to persuade him not to. The 55-year-old was sucked down a chute.
"One of his mates jumped off to try to rescue his mate, and the other guy went for help," Nelson police area commander Inspector Steve Greally said.
Travellers in the carpark below the falls rushed to help the third man, a 48-year-old from Kaiapoi, rescue the pair.
However, the water below the falls circulates in two huge whirlpools on either side, and this prevented the men getting out.
"[The rescuers] could see both of them going around and around and fighting against the current," Mr Greally said.
The man swept over the falls was eventually pulled from the water by the travellers, using two cargo strops tied together.
However, the friend who leapt to his rescue, also a 55-year-old from Christchurch, was seen floating face down in the water before disappearing.
His body was recovered by police divers about 3.30pm yesterday. Police have yet to release his name.
"We feel for the family and the man who was doing something heroic, albeit extremely dangerous," Mr Greally said. "When you see a friend in mortal danger, the natural inclination is to jump in."
The injured man was flown to Nelson Hospital with spinal injuries and was discharged yesterday.
Constable Willy Squires, of Murchison police, said alcohol may have been a factor in the incident.
Among those helping with the search was Murchison-based New Zealand Kayak School director Mick Hopkinson. He said he did not think improved signs would fix the problem.
Police had put emergency tape over the entrance following Saturday's incident but people were still climbing over the barriers, he said.
"You would need a 30-foot wall to stop people going over the barriers.
"It is dead easy to take the bureaucratic approach and blame DOC or the Government," Mr Hopkinson said. "It is the ‘ambulance at the bottom of the cliff' mentality."
The important thing was changing the national psyche about drinking and swimming, he said. Also, the correct water rescue protocol should be hammered into children at school.
Mr Hopkinson said that while the conditions in the area were not that fierce by kayaking standards, the bubbling, aerated nature of the water meant it would be difficult for anybody to stay afloat without a lifejacket.
"Ideally, one ought to first reach for a person in trouble with an object. If that fails, one should throw a rope, like in this instance."
If that did not work, rescuers should row out to the person in trouble, preferably with a lifejacket, Mr Hopkinson said.
"You should only swim to save someone as a very last resort, because you will find yourself in the exact same position as the person you are trying to save.
"We see these accidents happen all the time, unfortunately, with people acting on human instinct," he said.
DOC ranger Phil Crawford said signs were installed in a car parking area near the falls after the death of Ian Oliver Randall, 39, of Kaiapoi, who plunged over the falls in November 2011.
However, after Wednesday's incident DOC staff discovered that the signs had disappeared. They had probably been stolen and would be replaced as soon possible, Mr Crawford said.
Dr Smith said that if the signs had been stolen, they needed to be replaced immediately if DOC was going to take public safety seriously.
One of the Australian kayakers who rescued the Belgian tourist was Jonathan Cawood, president of Latrobe University's Mountaineering Club.
He said there were signs warning people not to go beyond the barriers when he last kayaked in the area a year ago, but there were no signs there last week.
The barriers were clearly ineffective, as the well-trodden ground beyond them showed that people were regularly jumping the barrier, Mr Cawood said.
The Belgian man was discharged from Nelson Hospital on Friday.
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