Work to address erosion and flood risk in Southshore and South New Brighton has been approved by the Christchurch City Council.
In Southshore, that that included replacing or covering structures along the estuary edge to reduce the erosion risk and constructing a new bund near the current one.
In South New Brighton a new bund would be built between the jetty near Beatty St and the southern end of the campground in Halsey St, and the estuary edge would be restored with a cobble beach.
Council staff said some of this work would reduce the flooding risk to 450 homes as well as a nearby campground.
The estimated cost to do this was $12.5m.
Prior to the council voting to greenlight the work Meg Roulston of the Southshore Residents Association told councillors it had been a long road to get to this point.
"The process for this beautiful and connected community has been arduous," she said.
"I want you to bring humanity to the estuary edge."
There had been concerns about people's wellbeing due to these issues remaining unaddressed, she said.
This work had been a long time coming, with many agencies involved – some of those organisations, Regenerate Christchurch and the Canterbury Earthquake Recovery Authority, no longer existed.
The vote to approve the work, subject to funding being agreed to in the 2021-2031 Long Term Plan, was unanimous.