Originally Posted by GreenIsGood
The holes should be 4 feet deep, not 4 inches. The hole dramatically increases the surface area for the water to perk out of. The weight of the water also helps with the perking - as the hole fills, the water is heavier and pushes the water down into the ground faster. It is possible for the hole(s) to fill, but regardless, they will drain much faster than the surface would have otherwise. If your problem is quite severe, do a second or third hole.
I had flooding in my side-yard and the "hole" / dry-well remedy didn't work at all. When it rained, a puddle about 6' wide by 10' long formed, with about 2" of water in it, on top of our undeveloped side yard (new house). I went on the internet and found that the easiest and cheapest solution was digging 4' holes like was recommended here. So I did it at the lowest point of the puddle (once it had dried out of course). And having left over energy that day, and wanting to avoid doing other obligations, I went on to dig 4 more holes, for a total of 5, 4-foot deep (aprx 2' diameter) holes.
I looked at my holes and was so proud of myself. Then the next Oregon rain hit, and it wasn't even a heavy one. And guess what? 4 of the holes filled up to the top and REFUSED TO DRAIN. To my amazement, they refused to drain even an inch for over 48 hours. I don't know how long it would have taken them to drain completely, because I pumped the water out.
The culprit: compressed, already wet (spring), super-heavy clay soil. So didn't work for me, had to fill holes in and do French drain instead. What perplexes me to this day, though, is that one hole (and they were all within 3' of each other, max) drained INSTANTLY and COMPLETELY and even looked dry after the rains. ??? That was like the "magic" hole or something. Still don't know what the difference was.