How do you plot Mean High Water and Low Water? (This is in reference to areas such as salt marshes and tidal estuaries) I have been plotting Mean High water as a coastline, which is correct as far as i know, however is there a facility or correct way to plot features (eg creeks/channels) at low tide? thanks 
PHerison
(P Herison)
2
Have you already found the articles about natural=coastline and Proposed features/Water cover?
ahh yes that’s what i was looking for, thanks 