Essex, famously, has the longest coastline of the English counties, not because it’s particularly long, more because it’s indented, like some of the Scottish counties. However there’s probably not that many miles of sea wall and even less of vertical sea wall where, when the tide is in, it covers the beach and comes right up to the sea wall. You don’t really need it if there isn’t a pavement behind it I’d guess.
They do have it in Westcliff though, and every now and again when the tide comes in you can hear this sound. This was recorded on The Western Esplanade just before Crowstone Avenue at about 11.35pm, so not too much traffic noise to drown out those bubbles.