There are many causes of CAT sheet rejection. Here are some of the common errors, and what to do instead.

1. Wrong datums (vertical and horizontal)

Vertical: all heights must be reported in NZVD2016. Submitting levels in the old Christchurch Drainage Datum is an immediate dead end - the sheet won't be processed.

Horizontal: geospatial data must be in Mt Pleasant 2000 (NZGD2000). If your survey software or output is set to a different projection, everything downstream of that point is wrong, even if it looks fine in the file.

Fix: check both settings in your survey software before you go to field, not after. Don't rely on inherited project files or defaults - confirm them every job.

2. Missing or misused mandatory fields

The CAT sheet has a number of structural rules that go beyond simply entering data:

  • Most cells that don't say "LEAVE BLANK" need to be completed - some from a controlled pick list (the green cells), others as free text.
  • Free text entries are capped at 30 characters per cell, so descriptions and IDs need to be written concisely.
  • Lines must be built in vertex order - from the lowest point to the highest point - and every line must start and end at a point that's also captured on the sheet, not one that only exists in the field data.
  • "At Pit" / "To Pit" fields in line data need to be filled with unique asset IDs from your points data.
  • Unique asset IDs (UIDs) need to stay consistent with what's shown on the drawings.

Fix: build the sheet with these rules in mind from the first entry, rather than treating them as a final check. Work through it methodically - cell by cell, then row by row - instead of relying on a read-through at the end to catch problems. Start with point data, then move onto line data.

3. Relying on GNSS for inverts and chamber levels

GNSS isn't accurate enough for the tolerances the CAT sheet expects for pipe and chamber levels. When it's used anyway, the levels often show up as strange, inconsistent variances that get interpreted as errors in the validation process.

Fix: use levelling or total-station methods for inverts and chamber levels. If you notice odd variances in your own data before submitting, that's usually a sign GNSS has crept in where it shouldn't be.

4. Missing or incorrect photographs (land improvement CATs)

Land improvement CATs require photographs, and they need to meet a specific standard:

  • Geo-referenced in the file's metadata (preferred but not required)
  • Shot in landscape orientation
  • Filed with a name that matches the corresponding cell on the CAT sheet

Fix: name and check photos against the CAT sheet rows as you go, not as a batch job at the end.

5. No redline drawings or survey report - or not enough in them

The required deliverable set is the CAT sheet, red-line marked-up drawings, a survey as-built report, and (for stations) the Stations Asset Pickup Sheet. Every redline page needs to be signed and dated, even where there are no changes.

Two things go further than the minimum requirement and genuinely speed up review:

  • Submit a CAD file showing the survey data in an easy-to-read layout. It helps council staff a great deal to have the data presented this way alongside the standard deliverables.
  • Fill in the survey as-built report tab with as much detail as you can. The more complete it is, the more likely a CCC data technician can resolve their own questions or clear up ambiguities without sending the sheet back to the contractor for rework.

Fix: submit the full set, not just the spreadsheet - and treat the report and CAD file as opportunities to reduce rework, not just boxes to tick.

6. Submitting something mediocre - and assuming it's done

Reticulation and parks submissions go via the portal; stations and land drainage go by email. Both portal and email submissions will eventually be reviewed manually, so problems that weren't picked up by the portal can surface later than you'd expect.

Fix: if there is something you don't understand, ask for help. Keep the CCC project manager in the loop, or ask them to put you in touch with the data team. Speak to a colleague with the right experience, or reach out to Anovo Services.

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