What is the water? Heavy rainfall, or has the very high tide levels stopped the rain water escaping, or, heaven forbid, has the tide level been so high that sea water has entered into the towns drainage system?
I cannot believe that is possible at the present time, but who knows for the future. It is not given much publicity but probably around a mile inland from Rhyl high street, around the Ffordd Derwen area, at very high tides water comes UP out of the drains for surface water. I've seen it, I used to live there. Mike