Thames Barrier

The Thames Barrier is like a really big gate in the river Thames in London. When the water in the river gets too high because of things like high tides or heavy rain, the gate can close to stop the water from flooding the city. The gate is made of big metal panels that can be raised and lowered using special machines. People who work at the Thames Barrier watch the water levels all the time to make sure the gate is closed at the right time to protect people and buildings from flooding.