BridgeWise Norfolk Broads

New: it now shows which bridge you are coming to, and explains what an air draft is for those who do not already know. Live Broads clearance, offline.

BridgeWise answers one question for anyone boating on the Norfolk Broads: can my boat get under that bridge, and if not, when?

It is not a tide table. It compares your boat's air draft against the predicted water level at each bridge, shows you the arithmetic behind every answer, and tells you plainly when it does not know.

WHAT IT DOES

• Clearance at Ludham, Wroxham, Acle and Beccles bridges, updated from live Environment Agency gauge readings • Passage windows where the tide genuinely opens and closes a bridge, and current clearance plus a weekly trend where it does not — the upper rivers barely move with the tide, and the app says so rather than pretending • The Great Yarmouth crossing, timed on slack water, showing what waiting for calmer water costs you in headroom • Moorings, with whether you can actually reach them right now and which bridge is in the way • A chart drawn on your phone, so it still works when the signal does not • Reminders to re-check as a window approaches

WHAT IT WILL NOT DO

It never says a passage is safe. The gauge board at the bridge is the authority and the app tells you to go and look at it. At Potter Heigham it gives you the bridge pilot's number instead of a verdict, because that is the correct answer there. At Great Yarmouth it gives you a time to aim for rather than a yes, because the tidal stream decides there and nobody publishes it.

Every verdict carries a safety margin built from named parts — how sure you are of your own air draft, how far the nearest gauge is, how old the reading is — and shows you which part dominates.

HONEST LIMITS

• Advisory only. Not a navigation chart: no depths, no channel markers, no hazards. • Bridge soffit heights start from published figures and improve as boaters record gauge board readings. • Tidal streams are not modelled anywhere. No open data publishes them for the Broads. • Covers the Norfolk Broads only.

Water level data from the Environment Agency under the Open Government Licence. Map data from OpenStreetMap contributors under the ODbL.