Skip to main content
Question

Two local authority boundary datasets, that should align but don't.

  • May 18, 2026
  • 3 replies
  • 68 views

jinman1883
Contributor
Forum|alt.badge.img+1

Hi, I have two local authority boundary datasets that should align along a river but don’t and this is causing the Master Lookup between the two boundary datasets to be wrong. These two should be aligned and coterminous. How do I easily solve it?

 

3 replies

hkingsbury
Celebrity
Forum|alt.badge.img+71
  • Celebrity
  • May 19, 2026

AnchoredSnapper is one approach. It would mean you have to chose the ‘correct’ boundary, then snap the ‘incorrect’ one to it

AnchoredSnapper


redgeographics
VIP
Forum|alt.badge.img+62

AnchoredSnapper is one approach. It would mean you have to chose the ‘correct’ boundary, then snap the ‘incorrect’ one to it

AnchoredSnapper

Ideally you would have a dataset containing the river centerline as well so you could use that as the anchor.

This is a tricky situation though, especially since it’s concerning boundaries. You need to be able to specify which boundary is the correct one. Otherwise you’ll be potentially introducing a border dispute.


donalmateer
Safer
Forum|alt.badge.img+10

Hi ​@jinman1883, thanks for the post!
Both ​​​​​​@hkingsbury & ​@redgeographics raise both good points!

To add to that, the river centreline as the anchor is the ideal scenario if you have access to it, as it removes the ambiguity of having to choose between the two boundary datasets.

If you don't have a centreline, just make sure you're very confident in which boundary is the authoritative one before snapping. Local authority boundaries are sensitive, snapping the wrong way could inadvertently introduce a discrepancy that's hard to unpick later.