IF the run is covered your water is raining in through the sides (minimal) and/or running in off of the gound though the wire around the parameter. Straw or hay will only make it worse and sand WILL NOT fix a coop that has standing water and stays wet from water running though it - you'll just lose a bunch of sand. You need to either build up the sides of the coop using a berm of some sort ot lumber or give the water someplace to go other than into the coop. I would personally go with the latter for a better fix, If you make a berm, the water can still get under it.
To make a french drain - go to the hardware store and get some perforated drainage tubing and the sleeve that goes over it. Dig a trench around the run about 6-8 inches deep and about a foot wide so that one corner is lower than the other three - needs to have a slope so that the water flows, but it does not need to be much. From the lower corner, dig a trench sloping down away from the coop for a few feet (5 should do). Lay down the pipe, conect all the corners and the outlet and cover with some crushed stone.
drainage tubing: http://www.lowes.com/pd_24139-124-0...nage&pl=1¤tURL=?Ntt=drainage&facetInfo=
sleve: http://www.lowes.com/pd_84666-71461...nage&pl=1¤tURL=?Ntt=drainage&facetInfo=
To make a french drain - go to the hardware store and get some perforated drainage tubing and the sleeve that goes over it. Dig a trench around the run about 6-8 inches deep and about a foot wide so that one corner is lower than the other three - needs to have a slope so that the water flows, but it does not need to be much. From the lower corner, dig a trench sloping down away from the coop for a few feet (5 should do). Lay down the pipe, conect all the corners and the outlet and cover with some crushed stone.
drainage tubing: http://www.lowes.com/pd_24139-124-0...nage&pl=1¤tURL=?Ntt=drainage&facetInfo=
sleve: http://www.lowes.com/pd_84666-71461...nage&pl=1¤tURL=?Ntt=drainage&facetInfo=