Hydraulic design for your new building or refurbishment
Water supply, hot water and drainage systems need to perform when your building is at its busiest, without adding unnecessary plant capacity or operating cost.
CPDT Consulting provides hydraulic engineering design based on calculated demand, available infrastructure and how the building will actually be used.
Jonathan Foster carries out the engineering himself, drawing on experience since 1997 across apartments, commercial buildings, stadium facilities, hospitality projects and aquatic centres and more.
His hydraulic expertise covers water supply, commercial waste, gas reticulation, plumbing, drainage, and large-scale hot water systems. Where rainwater harvesting is considered, Jonathan assesses both simple and advanced system options to help clients weigh the benefits, complexity, and overall suitability.
Existing system investigations and commissioning-related advice are also available. Contact Jonathan to discuss your project or current system performance.
CPDT Consulting provides hydraulic engineering design based on calculated demand, available infrastructure and how the building will actually be used.
Jonathan Foster carries out the engineering himself, drawing on experience since 1997 across apartments, commercial buildings, stadium facilities, hospitality projects and aquatic centres and more.
His hydraulic expertise covers water supply, commercial waste, gas reticulation, plumbing, drainage, and large-scale hot water systems. Where rainwater harvesting is considered, Jonathan assesses both simple and advanced system options to help clients weigh the benefits, complexity, and overall suitability.
Existing system investigations and commissioning-related advice are also available. Contact Jonathan to discuss your project or current system performance.
Hydraulic Services - Overview:
CPDT Consulting provides hydraulic engineering and plumbing design for new buildings, refurbishments and existing commercial facilities throughout New Zealand.
- Calculate water demand to help to ensure optimal sizing
- Demand calculations are complex, and are based on peak flow, consumption and recovery
- Assess drainage, stormwater, gas and water supply requirements as part of the wider building
- Evaluate rainwater harvesting and water-saving options against practical operating requirements
- Review existing systems to support refurbishment and replacement planning
- Coordinate installation, maintenance and future equipment access with the wider project team
CPDT Consulting is a Wellington-based building services engineering consultancy providing HVAC, hydraulic and commercial pool water design for projects throughout New Zealand.
Wellington | Auckland | Hamilton | Tauranga | Napier | Hastings | Palmerston North | Nelson | Christchurch | Queenstown | Dunedin
Page: Hydraulic Engineer Wellington | Hydraulic Services Auckland NZ - Last updated: 28th October, 2026
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- Size water and plant requirements using calculated demand
- Design hot water systems for reliable performance at peak use
- Plan installation, maintenance and future equipment replacement early
CPDT Consulting is based in Wellington and provides hydraulic design consultancy for building projects throughout New Zealand.
Hydraulic design backed by careful calculations
Accurate calculations help avoid both underperformance and unnecessary oversizing.
CPDT Consulting calculates water demand, supply constraints, and building requirements before sizing pipework, storage, and plant capacity. This gives project teams a clearer technical basis for design decisions rather than relying on broad assumptions or excessive safety margins
Whether coordinating high-flow wash-down supplies with civil engineers or calculating surge toilet flows for peak-use venues, Jonathan provides expected demand analysis to ensure hydraulic systems perform reliably under real-world conditions without simply increasing capacity “just in case", inflating upfront capital or running costs.
Discuss your building’s water demand and infrastructure with Jonathan.
Discuss your building’s water demand and infrastructure with Jonathan.
Large-scale domestic hot water design and sizing
Large-scale domestic hot water is a particular strength of Jonathan’s hydraulic work.
His experience includes apartment buildings, gyms, aquatic facilities and major shower hot water systems at stadiums in Wellington, Hamilton and Christchurch.
The system needs enough storage and heating capacity to cope with peak demand without creating unnecessary capital cost or ongoing energy use. Too little capacity can leave users without adequate hot water, while too much can increase cost without improving the outcome.
Jonathan assesses expected demand alongside design cost, construction cost, running cost, service life and maintenance requirements.
Pipework heat loss also matters. A system that looks adequate on paper can underperform if heat loss through long pipe runs or poor insulation is not properly accounted for.
For aquatic facilities, pool water services, HVAC and hydraulic systems can also be considered together to identify opportunities for better overall energy performance.
Rainwater harvesting and practical water savings
Water-saving systems only provide value when they suit the building, location and long-term maintenance requirements.
CPDT Consulting helps clients evaluate and integrate sustainable hydraulic designs through practical engineering assessments:
- Right-Sizing Storage & Reuse: Evaluate local rainfall data and actual building demand to select optimal tank sizes and rainwater or greywater reuse systems
- Managing Hygiene & Operational Risk: Specify appropriate filtration, contamination controls, and maintenance protocols so that water-saving systems operate safely.
- Balancing Efficiency with Performance: Assess low-flow fixtures against drainage requirements, ensuring water reduction never compromises the flow needed to move waste effectively through pipework.
Contact CPDT Consulting to determine which water-saving measures suit your project.
Coordination for installation, refurbishment and replacement
Hydraulic systems need to fit within the wider building, not simply work on a drawing.
Jonathan coordinates service routes, plant space, drainage levels, current HVAC services, maintenance access and future replacement requirements with the wider project team.
For existing buildings, investigations and option reports can help clients understand current plant condition, likely remaining life and what may need to be replaced or reconfigured.
This wider building services engineering approach helps identify conflicts before installation and provides more opportunity to plan practical access for future maintenance and equipment replacement.
No we don't. The construction industry is extremely complex, often requiring the involvement of many different specialist designers, contractors and planners. As such it is critically important that we all work together as a team, respecting and valuing one another's specialist inputs.
We strongly advise that clients engage our support through at least the end of the construction period to ensure that the design intent is delivered correctly and in accordance with the appropriate codes and standards.
We do not cover surface stormwater drainage or in-ground stormwater systems. That is typically the scope of a civil engineer. There is also no value in us getting involved with drainage off simple roofs, where our scope would effectively only be the downpipes. However, where rainwater from the roof is collected in storage systems for reuse or involves complex collection surfaces such as balconies, then we can design those. CPDT Consulting expertise covers water supply, commercial waste, gas reticulation, plumbing, drainage, and large-scale hot water systems
Yes. We design fully compliant trade waste interceptors and backflow prevention systems tailored to commercial kitchens, industrial plants, and specialised facilities.
Yes. We analyse local rainfall, building demand, filtration needs, and ongoing maintenance to ensure rainwater or greywater reuse delivers genuine value rather than operational headaches.
Hydraulic Services Summary:
- What: CPDT Consulting provides hydraulic engineering covering plumbing design, commercial hot water, drainage, stormwater, gas reticulation and suitable rainwater harvesting systems.
- Where: CPDT Consulting is based in Wellington and provides hydraulic engineering for building projects throughout New Zealand.
- Who for: Jonathan works with architects, project managers, contractors, building owners and other consultants on new buildings, refurbishments and improvements to existing hydraulic systems.