Webinar questions

The model assumes the network is working as designed. Partial blockages, gravel build-up, and pump station failures are considered as part of the ‘freeboard’, which is the extra room or safety factor built into the model.

Council spends about $1.5 million a year on stormwater pipe and open drain maintenance as well as sump cleaning and rural culverts and swales sweeping. Private property owners also have a role to play. Those with a stream or drain on their property are responsible for clearing debris, securing structures, and maintaining overland flow paths. People can also help reduce flood impacts by keeping their gutters clear, not blowing leaves and garden waste into the street, and clearing any drains or culverts outside their property.

Let us know about your property or changes to your property since 2017 by providing feedback at haveyoursay.kapiticoast.govt.nz/FloodMaps or by emailing the team with your address at flooding@kapiticoast.govt.nz.

The improved accuracy of the maps means some properties previously identified as being at risk of flooding or minor ponding might no longer be, while others who had not previously been affected may now find their properties included in the maps. A letter was sent on 28 April 2025 directly to the newly identified property owners.

Greater Wellington (GW) is responsible for managing flood issues related to the district’s major river catchments (Waikanae and Ōtaki Rivers) including the removal of sand and sediment from the mouths of rivers and streams in accordance with the requirements of the GW Natural Resources Plan. We are liaising with one of their teams on our flood modelling. Go to their website to find out more about GW’s regional flood assessment work.

There’s a NIWA managed website called NZ Flood Pics where anyone can upload their flooding photos. Go to https://www.nzfloodpics.co.nz/ 

Council also goes out during flood events to survey water levels and take photos to verify and calibrate the model.