Bit of a lot design this I think. This is an example of a drain on the promenade next to the beach. Add you can see it is full of pebbles and do just causes a flood. All the drains are like this. Pretty obvious this would happen I would have thought. When you have a grating like that next to a shingle beach.
Went did they not put some mesh in there? Surely it's common sense. You hardly need an engineering qualification to work that out.
Add you can see. My walk today was pretty soggy.