Posted: 17/02/2013 at 16:29
Keep poking holes, every 4 inches if poss and then brush in some sharp sand to aid drainage. This will take time and effort but will slowly improve drainage.
The other alternative is to rotavate the lot adding plenty of sharp grit and sand as well as some organic matter such as garden compost to the soil then let it settle, rake smooth, go over it with a roller or with your heels to remove air pockets, rake again and then sow new seed in early April when it's warm enough to germinate the seed and moist enough for it to grow.
The very serious alternative is to dig trenches and lay drains then put back the soil and proceed as above.
If you do give up and pave it, make sure you use permeable blocks and joins to allow run off in wet weatther or you'll end up with a more serious drainage problem in the rest of the garden.