Globally, no we do not have a water supply problem compared with countries like India and Ethiopia

Locally yes, as we have to manage our water using reservoirs and hose pipe bans are quite common

North West of the UK:
Heavy rainfall
Lower temperature
Less precipitation
Natural lakes
Less large cities
Less water needed for framing

South East of the UK:
Less rain
Higher temperature
More evapotranspiration
More cities
Greater demand for agriculture
And water needed for large cities