NUAR and Your CAT and Genny: Working Together
NUAR (the National Underground Asset Register) is the Government-backed digital map of the UK's buried pipes and cables. It tells you what is recorded as being in the ground; your CAT and Genny tells you what is actually there. The two are complementary, and on a safe-dig site you need both, because records are never a substitute for locating on the day.
NUAR is changing how site teams plan excavation. Here is what it is, what it is not, and how it fits alongside your locator.
What is NUAR?
NUAR brings the asset records of utilities, councils and other owners into a single standardised map, accessible to those who need it for planning and safe digging. Instead of chasing dozens of separate utility plans, a site planner can see a consolidated picture of recorded services in an area. It is one of the biggest improvements to dig planning in decades.
Does NUAR replace a CAT and Genny?
No, and this is the point that matters most. NUAR shows what is recorded. It cannot show services that were never logged, were logged in the wrong place, or have moved. Records are routinely incomplete or inaccurate, and unrecorded services are common. You still have to locate on the ground, every time, with a calibrated CAT and Genny, before you break ground.
How should the two work together?
- Plan with NUAR. Use the records to understand what services are likely present and where.
- Verify on site. Sweep with the CAT in all modes and apply the Genny to confirm and trace the actual services.
- Reconcile. Where the locate disagrees with the record, trust the locate and flag the discrepancy.
- Dig safely. Hand-dig trial holes to expose services before machine work.
NUAR makes step one far better. It does nothing for steps two to four, which is where your locator earns its keep.
What this means for your kit
Better records raise the bar for verification, not lower it. The expectation is that you arrive informed and then prove it with accurate locating. That puts a premium on a calibrated, capable CAT and good technique. Keep your unit in calibration, follow the method in our 2026 ultimate guide to cable avoidance, and treat NUAR as the best starting map you have ever had, not the final word. Browse cable avoidance kit to make sure your verification stands up.