A land swap between Nelson City Council and Foodstuffs will enable a larger New World supermarket to built in the suburb of Stoke.
Nelson Mayor Nick Smith said the council planned to use the land vacated by the New World in Strawbridge Square to replace car parking lost by the new development.
The new supermarket will stretch across the western side of the square, crossing the Neale Avenue entrance and covering the area currently occupied by the old Video Ezy building.
The council agreed to release around 846m2 in exchange for 1172m2 at the Songer Street end of the square, Smith said.
"It's a $20 million plus investment, it involves a switch of land with the council so that we can redesign the square and get the optimum supermarket, as well as improve the safety and the layout of the overall carpark."
There will also be a $600,000 stormwater upgrade in the area to address longstanding flooding issues.
"Strawbridge Square has had an awful problem every year or two with flooding, the store gets soaked and customers aren't able to access it. The council has made a commitment as part of the redevelopment to upgrade the stormwater system that will remove the flood risk - it's good for New World but it is also good for the Stoke community."
Foodstuffs South Island head of property strategy Rebecca Parish said there was a pressing need to upgrade the supermarket in Stoke.
"It is not fit for purpose anymore, that combined with the substantial stormwater flooding when we have a high rain event, we've got to the point where the store needs to be redeveloped."
The collaboration and land swap with Nelson City Council was a unique opportunity, Parish said.
New World Stoke owner operator Brendon Rae said customers often gave constructive feedback about the "current supermarket" and would ask about the plans for redevelopment.
"We are very excited about the next couple of years, it will be challenging at times but we know the project at the end will be amazing for the wider community."
Foodstuffs is currently working through the consenting process. It hopes to begin construction in early 2024 with the redevelopment taking two years to complete.