Divers should be able to inspect Eamont Bridge, and assess the damage caused by December's floods, throughout next week.
People and businesses have been badly affected by the closure of the bridge.
It's still standing, unlike nearby Pooley Bridge, but that makes it harder to find out exactly what is wrong with it.
Heavy rainfall has made it difficult for divers to get down to assess the damage.
Workers have now put up a dam to slow the flow of water directly beneath the bridge.
They hope this, along with a promising weather forecast, will allow divers to inspect the damage next week, and that repairs can follow soon after.
No timescale for repairs to Eamont Bridge has been provided.