The slide is one of two at Alpine Aqualand, an $18 million complex which opened at Frankton in May 2008.
By December, 69 patrons had reported minor injuries on the fast hydroslide.
At the time, then Lakes Leisure aquatics general manager Cam Sheppard said 51 of the incidents were caused by slide users breaking safety rules, such as standing up in the slide.
However, after a woman suffered a concussion and shoulder injury while using the slide, Lakes Leisure agreed to close it.
The Department of Labour investigated a complaint laid by the last woman to be injured, but who, last November, decided not to prosecute.
Since then the issue had been caught up in arbitration and while progress was being made, it was unrealistic to expect the issue to be resolved soon, Ms van Uden said.
Naylor Love was given the contract to construct Alpine Aqualand, with a subcontractor, Timaru manufacturer Aeromarine Industries Ltd, responsible for the design, building and safe operation of the hydroslides.
"It's frustrating. It's quite a complex issue and, as you are well aware, there are lots of issues around public safety.
"We are in the middle of an arbitration process at the moment. The good news is there has been some progress ... and without a doubt our goal is to get the hydroslide open and operating again, but it's got to be safe."
Ms van Uden said there was now "co-operation from all parties" and she had made it clear the matter needed to be resolved as quickly as possible.
"From my point of view, I would like to see it [resolved] as soon as possible [but] realistically it's probably not weeks, it's probably months.
"The pedal has been put to the metal - all the parties are working harder to get a resolution."
Ms van Uden could not discuss what the issues at the centre of the arbitration were due to "confidentiality agreements between all of the parties in the arbitration".
