Flood Assessment Certificates

If you are planning to build the Selwyn District and the property is within the Flood Management Overlay area you will be required to request a Flood Assessment Certificate from Selwyn District Council. Starting May 1, 2024, Selwyn District Council will require all Flood Assessment Certificate (FAC) applications for residential units to include a site/ topographic plan with ground levels and site benchmark mark in terms of NZVD2016 level datum. This plan is required to be certified by a Licensed Cadastral Surveyor to be in terms of the NZVD2016 datum. 

Eliot Sinclair’s Licensed Cadastral Surveyors specialise in providing this data in a timely manner so contact us for a free assessment of your next building project.

More information from the Selwyn District Council can be seen below or found at https://www.selwyn.govt.nz/pro...

Update: As of 1 May 2024, we are changing the information requirements for a Flood Assessment Certificate application. 

We will be requiring all applications for a Flood Assessment Certificate for a residential unit on a single urban site to include a site plan that includes existing site ground levels in relation to a datum reference for the top of the kerb in the road immediately adjacent to the site. This to be confirmed/certified by a Licensed Cadastral Surveyor to a datum mark which is permanent for use during the build. The datum reference shall be in New Zealand Vertical Datum NZVD2016 format. Finished floor levels will then be set at a level above this datum reference.

A Flood Assessment Certificate is a certificate issued by the Selwyn District Council that certifies whether the site or activity is likely to be subject to inundation and if it is, the appropriate minimum finished floor level to mitigate flooding risk.

Flood Assessment Certificates are required for all residential units or principal buildings, or additions to residential units or principal buildings of more than 25m² in floor area, where the site is located within the Plains Flood Management Overlay under the Partially Operative District Plan. To check if your site is within the Plains Flood Management Overlay, you can search for your property and toggle on the Plains Flood Management Overlay. The overlay covers most of the plains, so unless your property is on a hill, you are likely to need a Flood Assessment Certificate.

In reviewing many building consent applications for purpose of issuing a FAC we have observed that in some cases the datums referenced on the plans are not consistent with the datum references of flood information we hold. We have also observed that in some cases the site levels on the plans are not very accurate in relation to the actual site or road levels. Having a reliable NZVD 2016 datum will overcome these issues. It will also provide a benchmark for all other aspects of the proposed building that can be utilised by the designer and the builder. It is better the survey is carried out earlier than later in the project.

Setting finished floor levels in relation to a confirmed datum reference is simpler to comply with, reduces the potential for errors and gives certainty to the Council and homeowners that residential units and principal buildings are being constructed to the appropriate finished floor level. Using a known datum reference also better accommodates development on lots that are not completely flat.

If you would like us to set the floor level in relation to a known datum reference, you will need to reapply for a FAC. We will process this at no charge if you have had a FAC issued prior to 01 May 2024 and it has not expired.

Eliot Sinclair's friendly surveying team can advise you on the necessary requirements for your next project. Our Licensed Cadastral Surveyors are experts in providing the advise you need, on time.