The Severn estuary is an important habitat for birds; large barrages would destroy or damage much of it, as well as interfere with fish stocks in the river.

• 塞文河口是鸟类的栖息地，而大型水坝会在很大程度上破坏或毁坏河口，这同样也会破坏河流中鱼群的生态环境。