The road was closed immediately to protect the safety of the workers and any public driving or walking on that part of the road.
In mid-February, a fresh slip in the area occurred following heavy rain with a large amount of rocks and soil coming off the bank and big areas of debris hanging precariously above the road.
Council worked with a team of experts to assess the site, monitor various points on the slip face, and look at what could realistically be done long-term to stabilise the bank and restore access to the area.
Once the best option to do this was confirmed, work commenced in early April.
Work has included the cutting of wide steps into the slip face and reducing the angle of the slope to minimise the risk of debris blocking the road.
About 100,000 tonnes of material [about 70,000m3] has been removed which equates to 9300 truckloads (in a 7.5m3 truck) and enough rocks and debris to fill the Coastlands Aquatic Centre 25 metre pool in Paraparaumu 47 times.
"Kapiti Coast District Council has done an incredibly good job," Mr Campbell said on Friday.
"They would have had all sorts of pie in their face if it hadn't fallen, but it did fall in February, and it proved it was a risk for people.
"The job has gone well and there has been good communication with us.
"I'm full of thanks."
Kathleen said, "It has been an adventure.
"I've learnt to drive a four wheel drive and we've learnt about quad bikes.
"We've adapted to the situation but it has been hard at times."
Mr Campbell said the couple had survived via "help from up above" as well as a couple of helicopter drops from the Department of Conservation.
"We also had a fellow in a two man helicopter come down out of the sky one day and said 'can I help' so we said 'yes please' and he brought some stuff in."
He praised people who put them up for the night when it was too dark to walk the hour long emergency track.
And for the person who brought them about "20 litres of petrol one weekend and about 20 litres of diesel the next weekend".
"You can imagine what that was like walking the fuel through the emergency track."
Cr Jackie Elliott and her children made a special visit to the Campbell's and Mr Elgar on Saturday and gave them fresh bakery bread and a newspaper.
"The reopening of the Otaki Gorge, the gateway to the entire southern Tararua to Wairarapa ranges, is something for Otaki residents and businesses to celebrate."
Council infrastructure services group manager Sean Mallon said, "It has been massive job and we're delighted to get the road opened in time for the second week of the school holidays.
"It's great news for Otaki and we know local businesses will be pleased to see visitors to the popular tourist attraction coming back into our district.
"There's no guarantee slips may not happen again, but this work is all part of the on-going management of the slope that'll help reduce the risk of future road closures.
"We'll continue to keep an eye on the active area and are establishing a monitoring and cleaning programme that'll help ensure safe access to the Tararua Forest Park from Otaki long-term."
Work has taken more than three months and has an estimated price tag of $500,000 - almost half covered by a contribution from the Transport Agency's emergency works fund.
