Civil Engineering Consultancy · Napier, Hawke's Bay
Most consent delays come down to engineering. SAE Ltd delivers your solution — backed by a CPEng with 300+ completed projects across New Zealand.
What we do
SAE Ltd provides technically rigorous infrastructure design and flood assessment for residential developers, architects, planners, and councils across New Zealand.
Detention tank and swale sizing using HEC-HMS modelling, orifice design, and pre- vs post-development flow comparison. Applied under council-specific rules including NCC SW-S1 (stormwater neutrality), Auckland TP108, and RDC requirements. From a 6-unit infill with 16,000 L tank storage to a 500 m³ detention swale serving 41 lots. SAE established the NCC SW-S1 methodology now applied across Napier projects.
Learn more →1D and 2D HEC-RAS flood modelling on LiDAR terrain. Overland flow path analysis, finish floor level recommendations, pedestrian hazard mapping, and climate change scenarios (RCP 6.0 and RCP 8.5). Recent work includes a full 2D HEC-RAS study at Glendale Rd, Auckland on a 1 m × 1 m grid with depths to 1.2 m, and the Tukituki River assessment covering Q100 flows across three SCS variants — validated by Cyclone Gabrielle 2023.
Learn more → View the free NZ flood map →Complete stormwater, wastewater, and water supply network design for subdivisions from 2 to 90+ lots. Designed to NZS 4404:2010. Covers road layout, pipe sizing, pump stations, and engineering plan approval through to S224c certification. Applied from small urban infill to 90-lot greenfield developments at Hereford Heights and Henderson Line — including multi-stage S224c across different development programmes.
Learn more →Independent review and authorisation of civil infrastructure reports and resource consent applications by a Chartered Professional Engineer. Each report is reviewed at CPEng level - not delegated to junior staff. Suitable where a designer requires a CPEng sign-off for council submission.
Learn more →Selected work
A selection of projects that demonstrate the range of technical work SAE Ltd undertakes. Full case studies are available for each.
Full infrastructure design for a 74-lot subdivision. A box culvert design priced at $700,000 was challenged and replaced with a dual 1050 mm circular pipe system costing $100,000 — saving the client $600,000. The pipe analysis required detailed hydraulic modelling to demonstrate capacity equivalence. Multi-stage S224c. Project ran from 2020 to 2025.
Read case study →90-lot greenfield subdivision on 6.95 Ha. Horizons Regional Council required a 200-year flood design standard. Datum reconciliation between NZVD2016 and WVD1953 (0.543 m difference) was required to set accurate finish floor levels across all 90 lots. Multi-stage S224c delivered across the development programme. 2019–2022.
Read case study →Q100 flows modelled across three SCS method variants, returning 894–1,186 m³/s depending on variant. LiDAR dataset of 6 GB and 120 million points processed in Cloud Compare. The most conservative variant was adopted for all design levels. When Cyclone Gabrielle caused the Tukituki to flood in February 2023, Lots 1–5 in the assessed area had no flooding — validating the conservative approach taken in 2020.
Read case study →A WSP wetland classification that would have sterilised significant portions of the site was rebutted using historical aerial photography from 1942, 1949, and 1982, demonstrating the area had never functioned as a wetland. A 500 m³ detention swale was designed as part of the stormwater solution. Multi-agency consent required from both Rangitikei District Council and Horizons Regional Council. 2022–2023.
Read case study →The first project submitted under Napier City Council's new SW-S1 stormwater neutrality rule. Six units required 16,000 L of detention storage across four 4,000 L Tanksalot tanks, with 13 mm orifice outlets to restrict post-development discharge to pre-development rates. The methodology developed for this project has since been adopted as the standard approach for NCC infill projects. 2025.
Read case study →The process
Three straightforward steps from first contact to completed design and council sign-off.
Send us the site address, development type (infill, greenfield, or industrial), your council, and your timeframe. An initial response confirming whether SAE can assist — and an outline of what will be required — is provided within one business day.
A fixed-fee or capped-rate proposal is issued. Data collection follows: LINZ LiDAR download, council stormwater maps, existing consent conditions, and a site visit where the design requires it. Nothing proceeds without your agreement on scope and fee.
Design calculations, engineering report, and drawings are issued for your consent application. Council responses and RFIs are managed by SAE. For subdivision work, S224c certification is completed once construction is verified. You receive a CPEng-signed document ready for submission.
Coverage
SAE Ltd holds active experience with councils across five regions of New Zealand. Projects outside these areas are considered on enquiry.
Napier, Hastings, Havelock North, Central Hawke's Bay.
Councils: NCC, HDC, HBRC.
Marton, Bulls, Whanganui, Palmerston North, Feilding.
Councils: RDC, Horizons RC, WDC.
All zones including infill, greenfield, and industrial.
Councils: Auckland Council, Watercare.
Hamilton (Waikato), Bay of Plenty (Whakatane), Taranaki (Stratford).
Enquire for project-specific availability.
Send us the site address, council, and development type. We will confirm within one business day whether SAE can assist, what data is needed, and what the scope of work involves — before any commitment on your part.
