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Perth Hydraulic Design Consultants

Hydraulic Plans That Pass Council Approval First Time

Stormwater
NCC and AS3500 compliant documentation for commercial, multi-res, and institutional projects. Designed by licensed plumbers. Built for real-world construction.
βœ“ Compliance built in from day one (NCC, BCA, AS3500, Water Corp)
βœ“ Zero RFIs on multiple recent projects
βœ“ Full scope: water, sewer, stormwater, gas, fire services
βœ“ Coordinated with your architect and MEP team
βœ“ Fast turnarounds available when you need them
βœ“ Clear pricing with no vague scopes
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β˜…β˜…β˜…β˜…β˜… 5.0 Google Rating
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20+ Years Experience

Trusted by Leading WA Builders and Architects

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What Changes When Your Hydraulic Documentation Is Done Right

βœ“
Approvals
Without Setbacks
Council-ready documentation from day one. No revisions, no delays. When plans meet NCC, AS3500, and local requirements upfront, approvals move fast.
βœ“
Builds That
Run Smoothly
Clear, coordinated drawings your builder can follow. Fewer RFIs, no on-site guessworkβ€”everything aligned before construction starts.
βœ“
Projects That
Stay on Schedule
On a tight deadline? Documentation can be delivered in as little as 3 weeks (scope dependent), keeping your project moving without delays.
Stormwater management

Good on Paper Means Nothing If It Doesn't Work on Site

Builders say it too often: 'The drawings looked fine, until we tried to build from them.' Poor hydraulic documentation causes problems across the entire project.

❌ Plans that pass a desk review but fail on site because pipe runs don't fit, levels don't work, or services clash with structure

❌ Approval documentation that's missing key details, sending you back to council while your programme waits

❌ Designers who've never been on the tools, producing drawings that make sense in CAD but not in the ceiling space or under the slab

Bad documentation costs more than fees, it costs delays, frustrated crews, and fixes on site. The solution: construction-smart, coordinated docs built for approval the first time.
Builders say it too often: 'The drawings looked fine, until we tried to build from them.' Poor hydraulic documentation causes problems across the entire project.

❌ Plans that pass a desk review but fail on site because pipe runs don't fit, levels don't work, or services clash with structure
❌ Approval documentation that's missing key details, sending you back to council while your programme waits
❌ Designers who've never been on the tools, producing drawings that make sense in CAD but not in the ceiling space or under the slab

Bad documentation costs more than fees, it costs delays, frustrated crews, and fixes on site. The solution: construction-smart, coordinated docs built for approval the first time.
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The Approval-Ready Design Process

Step 01
Scope &
Clarify
You do: Send plans, drawings, or a project description.
We do: Review, clarify requirements, confirm scope and timeline.
What you get: A clear fee proposal with defined deliverables, inclusions, and realistic timeframes.
Step 02
Design &
Coordinate
You do: Connect us with your consultant team and provide updated drawings as needed.
We do: Design, calculate, coordinate, and document to NCC, AS3500, and local authority requirements.
What you get: Fully coordinated hydraulic drawings, calculations, schedules, and compliance notes ready for submission.
Step 03
Deliver &
Support
You do: Submit for approval and proceed to construction.
We do: Provide responsive support, answer authority queries, and issue amendments if required.
What you get: Documentation that supports smooth approvals and a direct line to us when questions arise on site.

What Builders, Architects, and Developers Say

Real feedback from people who need approvals to run smoothly and documentation that works on site

We Work With Builders, Architects, and Developers Across WA

πŸ—οΈ Builders and
Construction Managers
πŸ“ Architects and
Interior Designers
🏒 Property Developers
πŸ“‹ Project Managers
πŸ› οΈ Facility Managers and Asset Owners

Systems We Design

πŸ’§

Water Supply
(Hot & Cold)

πŸ§ͺ

Trade Waste

🚽

Sanitary Plumbing
& Sewer

πŸ”₯

Natural Gas

β›ˆοΈ

Stormwater &
Roof Drainage

πŸš’

Fire Hydrant
& Hose Reel

♻️

Rainwater Harvesting

β˜€οΈ

Solar Hot Water

❄️

Condensate Drainage

πŸ”¬

Lab Water
(Where Applicable)

Not sure if your project fits? Send us your plans and we'll confirm quickly.
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Independent Reporting

What You Get When You Work With Us

Comprehensive hydraulic documentation tailored to your project stage, with a clear scope and no surprises. You receive clear hydraulic layouts, floor plans, and riser diagrams that construction teams can work from, supported by design calculations for sizing, flow rates, and compliance with NCC and AS3500.

Fixture schedules are prepared for procurement and coordination, along with compliance notes and reports to meet NCC, BCA, and local authority requirements. All designs are fully coordinated with architectural, structural, and MEP consultants to prevent clashes before they reach site.

You also get responsive support for RFIs and site queries, efficient revision management as the project evolves, and organised, clearly labelled documentation ready for approval and construction.
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OTG VS Other Options

The Specialist Advantage OTG Typical Others
Hydraulic-Only Focus Our entire business, not a side service inside a larger MEP firm. βœ“ βœ•
Trade-Backed Design 20+ years experience starting from the tools. We design what actually builds. βœ“ βœ•
Compliance Guarantee If our docs fail approval due to non-compliance, we fix them free. βœ“ βœ•
Fast RFI Turnaround Same-day or next-day responses typical during construction. βœ“ βœ•
Pre-Issue Coordination Documentation aligned with your architect and MEP team before it leaves our office. βœ“ βœ•
πŸ›‘οΈ Guarantee Statement

All hydraulic designs and documentation are prepared to meet or exceed current NCC, BCA, AS/NZS 3500, and relevant local authority requirements.

If any documentation we provide fails approval due to non-compliance, we revise it promptly at no additional cost.
βœ“ Coordination Guarantee

If clashes within our scope are identified, we resolve them quickly to keep your project on track.

βœ“ Responsiveness Guarantee

We respond to RFIs and coordination requests within agreed timeframes. No chasing required.

βœ“ Scope Clarity

Your fee proposal confirms deliverables, inclusions, and timelines before any work begins.

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Call us or request a quote today to find out how we can help!
Call us 24/7 for expert advice.
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Hydraulic Design Specialists
Perth. Sydney. Brisbane. Melbourne.
Accreditation

OTG designs and delivers projects in line with the National Construction Code and adheres to key Australian Standards including:

  • AS 3500 series for plumbing, drainage, stormwater, and heated water services
  • AS 5601 for gas installations
  • AS 2118, AS 2419, AS 2441, and AS 2941 for fire safety systems

Our commitment to these standards ensures the highest levels of safety, efficiency, and regulatory compliance in every project we undertake.

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Licensed Plumbing Contractor: PL8000
Gasfitting Permit: GF12399
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