4 way pallets question

[happybees]

I have my hives on 4-way pallets with strips, which create the entrance.  Two hives face the opposite direction of the other two. During the rainy season, a lot of water gathers at the bottom of some hives.
 I guess, the rain gets mostly through the entrance, if the pallet is inclined  or through other cracks. Moisture stimulates the mold growth and is bad for bees. I had a case when bees bearably were able to get out through the entrance, because water was so high.  
I made some holes on bottom boards (pallets), but they got clogged with dirt.
Now, I want to reconstruct the hives to keep the water away. Any suggestions will be appreciated. Thank you.    

[rdy-b]

one thing i notice this year i had to buy extra pallets -the pallets i run dont have any decking between the hives -but the pallets this year had solid plywood deck -rain watter builds on the deck and runs under the beeway strip-so i made weep holes-inside the hive area and the deck between the hives-the weep holes had to be at least 1 inch (how big did you make yours)-so now the mice can get in but mice go where it is dry so if you have the pallets with the continuos deck  the problem is worse than the pallets with open deck-any way somtimes it is condensation-sometimes rain-but with pallets there are always two hive that the watter runs to- RDY-B

[MacfromNS]

When I make my bottom boards, I make them to drain out the front so you don't have to lean the hive.Now for the ones you already have, put a piece of 1x1 under the back side.