Manhole inspections & pipe snapping

Overview

Manhole and pipe snapping lets a linear feature (e.g. a pipe) snap its start and end nodes to point features (e.g. manholes), with attribute values flowing automatically into the pipe for calculations like cover level differences and falls.

How It Works

When a linear feature with snapping is created, it pulls attribute values from the manholes at its start and end. If a manhole changes, the pipe's geometry and calculations update automatically.

Setting Up the Point Feature Type (e.g. Manhole)

In the web portal, edit the manhole feature type:

1. Add a short-text attribute named _recalc_snaps.
2. Set its value to !MODIFIER-HIDE to hide it from the form.

This triggers recomputation of any snapped linear features when the manhole changes.

Setting Up the Linear Feature Type (e.g. Pipe)

Add attributes using these default value tokens:

• !SNAPPEDSTART(attributeName) — value from the manhole at the pipe's start.
• !SNAPPEDEND(attributeName) — value from the manhole at the end.

Example — cover level fall:

1. Manhole has COVER_LEV (cover level in metres).
2. Pipe adds UpstreamCoverLevel (default !SNAPPEDSTART(COVER_LEV)) and DownstreamCoverLevel (default !SNAPPEDEND(COVER_LEV)).
3. Pipe adds Fall with default !CALC $UpstreamCoverLevel - $DownstreamCoverLevel.

Captured Workflow

1. Capture both manholes, entering their COVER_LEV values.
2. Start a new pipe feature; snap its start and end nodes to the manholes.
3. UpstreamCoverLevel, DownstreamCoverLevel, and Fall populate automatically.
4. Editing either manhole recomputes the pipe on save.

What's Next?

• Mobile App Data Entry Shortcuts
• Creating Feature Types
• Alignment and Chainage