RM9: 46 of 568 postcodes stand below a spring high tide

The ground at 46 of RM9's 568 postcodes (8%) is lower than an ordinary spring high tide at London Bridge (3.9 m above Ordnance Datum).

• Ground at eight in ten of its postcodes: between 5.1 m and 11 m, measured from Ordnance Datum; the middle one stands at 6.9 m.
• 65 of 568 stand lower than the 1953 tide (5.41 m).
• 50 lie in the Environment Agency's Flood Zone 3 from the sea, mapped without defences.
• Mostly in Barking and Dagenham; partly in Havering.