About Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments known as ecotone.
Water firms illegally spilled sewage on dry days - data suggests

... The BBC analysis suggests that Thames Water - with customers from the Cotswolds to the Thames Estuary - dry-spilled for 1,253 hours in 2022, at 49 overflow sites...
COP26: Flooding lessons from Hull, a city below sea level

... The River Hull snakes through its centre and out into the Humber Estuary - a shipping port and gateway to the nearby North Sea...
Sir David Amess: What does city status mean for Southend?

... " It also has London Southend Airport, and just up the river are the ports of London Gateway and Tilbury who have come together to develop Thames Freeport with its exciting visions for the future of the Thames Estuary...