Then, with the road due to be opened another slip occurred, extending the closure.
Approximately 13,000cu m of rock and debris have been cleared from three slips since the road was closed on April 24 - enough to fill more than five Olympic-size swimming pools.
Before this latest closure the road has been closed more than 30 times because of maintenance, slips and accidents, nine times in 2015 and the 14-month closure in 2011.
Mrs Collis said when the first slip occurred on April 24 she, along with many business people, hoped the initial reopening deadline would be met.
But now the NZ Transport Agency has said newly uncovered structural damage to the highway through the gorge, caused by recent slips and heavy rainfall, means the road couldn't be safely re-opened to traffic as planned.
NZTA highway manager Ross I'Anson said detailed inspections undertaken by structural engineers before the planned re-opening of the highway revealed a concrete retaining wall supporting the road has shifted and must be replaced.
The damaged retaining wall on the river side of the road was discovered after slip material was cleared near Kerry's Wall, 4.5km from the Ashhurst turn off, which has been the site of several slips since the closure of the road on April 24.
"We've looked carefully at the option of opening the road to a single lane while this retaining wall is replaced and the road is repaired, but further heavy rain in the gorge on Wednesday has made the area more unstable. In its current state the width of usable road surface at this slip site is very narrow. We would need to have vehicles passing directly under the slip while the work is carried out, which would pose unacceptable safety risks for road users," he said.
"We know how frustrating this news will be for people, and we know how vital this route is for the region, but we simply can't re-open the road before it is safe for people to use. We're focused on getting the road re-opened as soon as possible, and our crews are working hard to get the job done."
Mrs Collis said she feels for the Woodville businesses trying to cope with an never-ending stream of bad news.
"It's such a blow to the community and the worst possible outcome. It's critical for businesses to be able to plan stock and staff, but it seems every time there's movement in the gorge we're faced with more closures.
"This doesn't provide any reassurances for business people in Woodville. Unfortunately, the new slip bought back memories of 2011 with further holdups and dates not being met. I am concerned that with each disturbance comes additional risk and we need to start the discussion for a long term solution.
"The Saddle Rd has been upgraded although it is not fully complete yet. It was always designed as an alternative route and isn't ideal for long periods of heavy use.
"We could never spend enough money on the Saddle Rd to bring it up to standard, with the vertical alignment and a gas pipe running beside it."
Work on the Saddle upgrade began in early 2014, involving road widening, better drainage, new kerbing, fencing and additional passing areas. The work was seen as a priority after the Manawatu Gorge slip in 2011 and has been a collaboration between the NZTA, Tararua District Council, Manawatu District Council, Palmerston North City Council and the Tararua Alliance.
Initial estimates were for $4.5 million to be spent over two years, but an additional $3.8m from NZTA has allowed for more work, pushing out the timeframe.
Mr I'Anson said the new timeframe for re-opening the road to traffic will be determined by how quickly the concrete retaining wall could be replaced and while the work will be done urgently, the road is likely to remain closed to traffic for another week.
"At this stage the repairs are not expected to be completed before the end of next week, but as soon as the repairs are done it is safe for traffic to use the road it will be re-opened, initially to a single-lane at the slip sites," he said.
Mrs Collis said it's now urgent for the region's mayors and chief executives to start planning for a secure link.
"NZTA showed options on television ranging from bridging at $415m, alternate routes at $120m to $300m and a tunnel at $1.8 billion," she said.
"I have often discussed the option of a toll tunnel as an effective link between here on the east and Palmerston North and the Feilding districts. The economic benefit of the link is important to business and employment opportunities, population growth and freight to the Napier port. It is timely to have these discussions now so we can plan for the long term benefit of the region."
However, Tararua District Council's chief executive Blair King has previously told the Dannevirke News he doesn't believe a tunnel is feasible.
"Some of the material they would be boring through has been described as dry Weet-Bix." Mr King, an engineer, said. "Prospects for a road tunnel through the gorge don't look good when a proposal for a tunnel through the Rimutakas hasn't stacked up."
And Wairarapa MP, National's Alastair Scott agrees.
"A tunnel isn't an option," he said. "The future viability of State Highway 3 through the Manawatu Gorge is all about the economy and connectivity. We're always talking about making the world a smaller place and the Manawatu Gorge is a big connect, vital to the economy of the regions," he said. "Imagine if it [the gorge] was a straight piece of road ...
"So, if we can make it a little bit less stressful that would be great and while a tunnel isn't the answer we can have a much improved road, maybe suspended around the slips. Yes, it would cost a lot of money, so anything would be dependent on the economic benefits. But a secure road would strengthen the region's economy."
Mr Scott said in the past 20 years the Manawatu Gorge road has been improved, but he'd like to see the upgrade of the Saddle Rd continue and more money spent on the Pahiatua Track.
"We [National] have announced an extra $11 billion in the budget for infrastructure, including spending on roads of national significance like the Manawatu Gorge," he said.
"More freight is moving through the gorge and it's only going to increase, so we'll be putting continued pressure on NZTA to look at what can be done with the Manawatu Gorge."
Mrs Collis said many Woodville businesses have suffered from the reduction in traffic flow, with the Bridge Cafe feeling the road closure more than others.
"However, I am impressed at owner Rebecca Algie's use of social media encouraging people to come along and support the cafe and it's working," she said.
"I've visited the cafe twice during the gorge closure and each time locals have been there just to show their support. International tourists have also continued to visit, which shows the benefit of tools like TripAdvisor because this is a deliberate choice of destination for them. The use of digital media is a vital part of the Bridge Cafe business, the reviews are great and it works for them in good times just as much in tough times when the gorge is closed."
Mrs Collis said Woodville's Caltex service station has also experienced a drop in business.
"They're missing out because motorists are bypassing the town and because those from Pahiatua who would usually travel via Woodville are now choosing the Pahiatua Track as an alternative."
Meanwhile, a meeting has been arranged with the mayors and chief executives of Tararua District Council, Palmerston North City Council, Manawatu District Council and both Horizons and Hawkes Bay Regional Councils to discuss the gorge, Mrs Collis said.