Newbie here just dug into clay now it's water logged help

Ive digging up a section of garden which slopes upwards towards the rear of my garden from my patio in attempt to flatten it to lay some more patio or artificial grass .
But I've now dug into clay and its clogging up with water it looks like a pond what should I do theres no obvious way to drain it has there is a wall on either side .
Should i dig a small trench and fill with gravel at the lowest point , would i be ok to then put grit sand down and tarpaulin then artificial grass?

 

Welcome to the forum @Malibu200786 . I don't know what you should do but there are lots of members here that will probably pop in to help.

If you have time to update your profile to include your location, it might help others give advice appropriate to your zone.

 

Welcome Malibu200786.

Photo's of the area would be a great help please.