our garden slopes down to a park which is beyond a common access
track.

the garden has always been wet and after a lot of rain water would
push up between concrete cracks at the bottom of the garden. This
didn't matter much.
Last year the poplar in the park beyond died and its been fairly wet.
We now have a boggy patch in the lawn and water running down the path,
one small bed is totally waterlogged. Beyond the garden outside the
neighbours back gate the water accumulates because it cannot get
beyond a slightly raised concreted section at the back of the
neighbour two away, I doubt anything not 4x4 could now get through the
access track.
Where would you start looking for a solution, Thames water? The
Council? Some DIY work?
--
Mike