Horokiri Catchment Flood Mapping
At the drop-in session on Wednesday 3 December 2025 evening residents were able to look at the prepared flood depth maps and to share their knowledge and experience of the Horokiri Catchment.
It was good to see the post-it note comments on the maps and Wellington Water and Awa consultants will be following up on these.
If you were unable to attend the session, or did but would like to look at the maps again, Wellington Water have provided the link to the online flood maps for Porirua. These can be found in the Maps currently being validated within the community tab. This tab shows the 1 in 10-year modelled event and the 1 in 100-year (including climate change) modelled event.
There are instructions for using the maps on the left-hand side, with a sliding line that lets you compare the two maps
Note: the maps showing the historical flood depths that were shown on Wednesday evening are not available online.
We have been asked if there is a way of sharing further photos or videos with Wellington Water, appreciating that sometimes these are large files. PRA has a Dropbox arrangement with Wellington Water so if you have such material please let us know and we will work with you to get these to Wellington Water. Wellington Water have also provided the following email address if you have further questions or material to share floodmap@wellingtonwater.co.nz
These are the last versions of these particular maps that we will see as they show modelled flood depths. When the maps are next released, in preparation for inclusion in the District Plan, they will be presented as Flood Hazard maps, showing Stream Corridor, Overland Flow, and Inundation areas.
The process from here will be
- A change to the district plan is written, a “plan change”, which is notified to the public
- There is a statutory period of submissions, and then further submissions to the plan change
- A report from Porirua City’s planner is taken to an Independent Hearings panel, to make the decision on the plan change
- There is then an appeal period where submitters can appeal to the Environment Court
At the moment PRA does not have any information on the time frames but we will be following the process and keeping you updated.
Meantime, there is a lot of information on the council's website including under the FAQs
and if you have questions feel free to contact usWellington Water floodmap@wellingtonwater.co.nz
or the Council Climate and Environmental Planning Team districtplan@poriruacity.