Hi all been working on a new garden project, new garden is clay and wet!

I rotavated and amended the lawn area several weeks ago and turf is growing and rooting great however I decided to dig over the beds with a view to remove the substantial builders rubble and heaviest clay lumps

Bed is around 1.5mx9m by around 300/350mm deep

After some rain last night I came down to find the empty end of bed FULL of water like a bathtub the full 350mm deep 24hrs after raining, must be seeping in from other parts given it's now the lowest part.

What should I do? The worst bit is the empty part so as there is no resistance there water is flooding im but what if i follow my original plan to level out the remaining clay soil and mix it back into the bed with 1-2 tonne compost?

Or...

Am I doomed here now and need drainage solution to reroute which is not ideal

Image attached