As various government members make promises about funding for flood defences, while wavelets lap gently against the interior walls of thousands of dwellings, my thoughts naturally turn to King Canute. I gather he was a real king (Cnut, Knutr, reign 1016-1035, Danelaw zone only). He seems to have been a very competent leader, so if it is true that he sat on his throne on the seashore and commanded the waves not to advance, I feel sure he did so to make a point to his courtiers about the futility of claiming power over nature, rather than because he actually expected the waves to take any notice.
Perhaps there is a lesson for us here. I would guess that a modern King Canute would not trust entirely on grand engineering projects in a costly and perhaps futile effort to cope with forces whose scale was simply too great.
I am no expert, but I have consulted people who are, and I am convinced that the key is prevention, or at least mitigation: to plant belts of trees on hilltops and slopes to absorb rainfall and anchor topsoil in place. King Canute would not recognize England today: in his time there were vast tracts of forest. I think he would be aghast. The terrible mudslides in the Philippines of late were a more extreme result of essentially the same human activity - cutting down trees.
As for the endless miles of built-up areas in modern Britain, while we wait for government measures to replace impermeable surfaces with permeable ones which allow rainwater to soak away slowly, we can help at the individual level by installing water-butts, not concreting over our yards and gardens, and if we have to make a roadway or hard standing, using gravel, or pavers laid on sand, as I noticed they do in Amsterdam.