Owain wrote:
Tim S wrote:
Building regs surely?...

Planning regs can specify how surface water is disposed of, and if the
drainage in an area is inadequate then planning can be refused.

Owain

I am not sure it works that way.

you can surely have planning permission for something without specifying
te details of how its built. My sketches got planning permission: It was
only later on that the details were drawn up to comply with building
regulatons