Flood risk across Southwark
North Southwark — Bankside, Borough, Bermondsey and Rotherhithe — is low-lying tidal floodplain protected by the Thames Barrier and river walls, so much of it is in Flood Zone 3. Further south, in Peckham and Dulwich, surface water from heavy rain is the main risk.
Flood zones only show river and sea flooding, and they ignore flood defences. Surface water and reservoir risk aren’t part of the zones – check them on the Environment Agency’s long-term flood risk service, or get the full report, which covers every source.
Rivers that shape local flood risk
Main rivers are managed by the Environment Agency. Smaller watercourses and drainage are the responsibility of Southwark Council and landowners.
River Thames – Tidal along Bankside, Bermondsey and Rotherhithe
River Effra – A buried river, now a sewer, under Dulwich
River Peck – A buried river, now a sewer, under Peckham
River Neckinger – A buried river, now a sewer, under Bermondsey
Who manages flood risk here
Southwark Council is the Lead Local Flood Authority, responsible for surface water, groundwater and ordinary watercourses. The Environment Agency manages main rivers and the sea, and issues flood warnings. The same council also decides planning applications – and asks for a flood risk assessment in Flood Zones 2 and 3.
Getting a written answer for an address
The free check describes the area around your postcode. For a specific property, the full report checks your exact address against every flood dataset and gives you a dated PDF to share with your surveyor, conveyancer or insurer.
For planning decisions, your local council has the final say.
