Thames Barrier closes for annual test before 200th operational closure

The Thames Barrier is a crucial flood defense system protecting central London from tidal flooding. It spans 520 meters across the river and has closed 199 times for flood defense, with a total of 613 closures including tests. The barrier consists of 10 gates, with the largest being 61 meters wide and weighing 3300 tons. These gates can be closed in 8 to 12 minutes. The barrier's use is expected to increase over time, with normal operations taking about 1.5 hours. However, in urgent situations, it can be closed in as little as 45 minutes.

What is the expected trend in the usage of the Thames Barrier in the coming years?

What is the typical duration for normal barrier operations?