The run became an issue when my girls so quickly ate through all the fresh green grass that once filled it.
It turned into a sloppy muddy mess come fall, and it became apparent that the run was in a lower spot than I thought.
At first I dug up chunks of sod from our field to fill in the lowest spots. The girls got more grass, and the ground was a bit higher - but again, it turned into a sloppy mess very quickly. Plus, it was a LOT of work to dig that up, wheelbarrow it in and distribute (chunks of sod are heavy!). Even with new eavestrough, it just couldn't handle the amount of rain and water.
Solution: We filled it with two yards of construction grade sand (washed), and it's been perfect since. We graded it from the edge of the coop toward the back so the water will drain quickly. I love it! My girls love it! Everything is clean and dry (including their feet), which reduces risk of bacteria and illness. With winter, it's easy to shovel snow out of the run with a smooth gravel bottom, rake out frozen chicken poo, and I don't have to worry about spring melting now.
We got extra sand to fill in the coop as well, and it continues to work amazingly in there. It slowly needs to be replaced as I scoop out sand covered poop, so I keep the leftover sand in our "barn" where it stays loose and dry. Because there's so much snow now covering their big doors (where I would normally wheelbarrow it in), I simply make a couple trips filling a bucket and distributing it that way. This isn't done very often, so it's not a big deal. So far, I've topped it off three times since the coop was finished in the summer.
Knowing that my girls have a comfortable and safe area to hang out in makes me very happy.