Regional Service Station Retrofit

Project Overview

Calibarium MEP provided a targeted estimation package for a service station retrofit in regional Queensland. This compact commercial project demanded efficient quantification across plumbing, sanitary drainage and stormwater, with a strong emphasis on sustainable water management through a 23,000 litre rainwater harvesting system with integrated first-flush diversion.

Despite its smaller scale, the project required careful detail: underground services had to accommodate existing site constraints, and the fire safety scope included sprinkler modifications, smoke detectors and EWIS (Emergency Warning and Intercommunication System) components.

Scope of Work

Water Reticulation

• 105 linear metres of 20 mm non-potable cold water (in-ground)
• 32 mm rainwater reticulation and 25 mm cold water mains with isolation valves
• 3 RPZDs for backflow protection across potable / non-potable boundaries
• Pressure limiting valve (500 kPa) and 20 mm water meter assembly

Stormwater & Rainwater Harvesting

• 225 mm stormwater lines: 67 linear metres
• 150 mm stormwater lines: 95 linear metres
• 23,000 L rainwater tank (2.6 m × 2.6 m × 2.7 m) for water re-use
• First-flush system with integrated valves to divert initial contaminated runoff

Fire Safety & Detection (Modification Scope)

• New and relocated semi-recessed pendant ceiling sprinklers and concealed space modifications
• CO2 and dry powder fire extinguishers (new installations)
• New, relocated and additional smoke detectors
• EWIS speakers and electromagnetic door holders

Technical Highlights

• Sustainable water strategy: the 23,000 L rainwater tank with first-flush diversion ensures contaminated initial runoff is diverted before clean rainwater is captured, maximising quality for re-use.
• Retrofit complexity: working within existing building constraints required careful coordination of new piping with existing services, including fire sprinkler deletions and relocations.
• EWIS integration: emergency warning and intercommunication speakers, a critical life safety requirement under Australian standards.
• 210-hour excavation programme: reflecting the scale of new services installation in an operational site.

Outcome & Impact

Calibarium MEP delivered a precise, cost-effective estimation package that balanced the compact nature of the project with the technical rigour required for commercial service station standards. The integration of sustainable water management, particularly the first-flush rainwater system, demonstrated our ability to embed environmental best practice even in smaller-scale commercial projects.

Disciplines in Scope