Rescue work being done to damaged dam at Toddbrook Reservoir

The video discusses the need for the Environment Agency to manage reservoir water levels by diverting water into river boats. However, heavy rainstorms are complicating the process as water levels rise as quickly as they are lowered. Volunteers from a local mountain rescue team are assisting by placing sandbags to help control the situation.

What is the purpose of lowering the reservoir level?

What challenges are faced in the process of managing the water levels?