W12: 20 of 815 postcodes stand below a spring high tide

The ground at 20 of W12's 815 postcodes (2%) 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 4.6 m and 12 m, measured from Ordnance Datum; the middle one stands at 6.2 m.
• 228 of 815 stand lower than the 1953 tide (5.41 m).
• 197 lie in the Environment Agency's Flood Zone 3 from the sea, mapped without defences.
• Mostly in Hammersmith and Fulham; partly in Ealing.