Fire Hydrant Flow & Water Pressure Testing
Flow Consulting provides backflow prevention cross-connection surveys, water supply risk assessments, backflow philosophy reporting and hydraulic design advice for existing buildings, proposed developments and building upgrades. We help property owners, developers, contractors and design teams identify potential contamination risks and determine appropriate prevention measures.
Using on-site investigations and project-specific desktop reviews, we assess water supply arrangements, identify actual or potential cross-connections, consider hazard classifications and provide practical recommendations. Our findings support remedial planning, building design and responses to relevant council and regulatory requirements.
Understanding Backflow & Cross-Connection Risks
Backflow occurs when water reverses its intended direction, potentially allowing contaminants to enter a potable drinking water system. This can result from back-siphonage when supply pressure falls, or back-pressure when pressure elsewhere in the system exceeds the supply pressure.
Cross-connections may occur wherever drinking water is connected directly or indirectly to fixtures, equipment, storage systems or processes capable of introducing contaminants. Recognising these risks is essential to protecting building occupants and the wider public water supply.
Backflow Prevention Surveys & Existing System Assessments
Flow undertakes surveys of existing water supply infrastructure, potentially extending from the property boundary or point of supply through to fixtures and equipment throughout the site. We review how water is supplied and used, site activities, potential cross-connections and the protection already installed.
Where appropriate, surveys document observed water supply components, device locations and condition, hose taps and other potential risk points, supported by photographs and written observations. We also review existing plumbing arrangements and as-built drawings to assess whether current protection remains suitable or further investigation or remedial work is needed.
Existing physical separation or other compliant arrangements may already provide adequate protection. Our assessments focus on actual site conditions rather than automatically recommending additional devices.
Hazard Classification & Regulatory Requirements
The activities carried out on a property, its water supply configuration and connected equipment all influence the potential hazard level. Flow assesses these factors to inform the hazard classification and suitable prevention strategy for the site.
We consider relevant New Zealand Building Code provisions, water supply and backflow standards, local authority requirements and water supplier policies. Requirements vary by territorial authority and supplier, and may address surveys, boundary protection, device registration and ongoing testing.
Backflow obligations may arise from new building work, alterations, changes in property use, council water supply conditions or reviews of existing commercial and other premises. The final protection requirements depend on the site and the responsible authority's rules; our reports provide technical information to support discussions and next steps with that authority.
Backflow Philosophy, Design & Protection Strategies
For proposed developments, building upgrades and existing facilities, Flow prepares backflow prevention philosophy reports setting out an appropriate method of protecting potable water supplies. These may be based on available drawings and project information or informed by a site survey.
A philosophy report can identify the incoming connection, known hazards, proposed hazard rating and the required level of protection. Containment protection at or near the boundary protects the public supply; zone protection addresses particular areas or groups of equipment; and individual protection addresses specific fixtures, outlets or equipment.
Depending on the assessed hazard and applicable requirements, options may include air gaps, hose connection vacuum breakers, double-check valve devices or reduced-pressure-zone devices. We can recommend device types and locations and identify further hydraulic design or installation considerations. Not every property requires all three levels of protection or an additional device at every point.
Reporting, Recommendations & Project Support
Our survey reports can record site details, incoming water supplies, observed fixtures and equipment, existing prevention devices, identified hazards, risk considerations and recommended remedial measures. Supporting material may include photographs, drawings, device locations and references to applicable requirements.
Philosophy reports focus on the proposed prevention methodology and the measures appropriate to the project. Both types of reporting are intended to support informed decisions, design development, remedial planning and discussions with the relevant authority. Physical installation, commissioning, device testing and certification are separate services unless expressly included in the agreed scope.
Whether a client is planning a new facility, upgrading an existing building, responding to a council requirement or reviewing a complex installation, early assessment can help avoid costly design and construction changes. Flow combines hydraulic design knowledge with practical survey and reporting experience to clarify existing conditions and recommend proportionate next steps.