Hello - I am a falconer and I am looking for some help in creating a system to keep water from accumulating on the floor of the chambers that my hawks live in (called Mews). I have an 50+ year-old 19 x 19' wooden building with a flat concrete slab base that I have converted into two hawk houses that are seperated from each other with a plywood wall.

I would like to have a pea-gravel floor for the mews because it is good for the feet of the birds and won't damage their talons however there is no drain in the concrete and if the water sits it can form bacteria which is deadly for the birds as it causes aspergilliosis. Gravel is also easy to clean and disenfect with a hose sprayer when there is a way for the water to drain out. Currently I have astroturf over the bottom of the mews which is hard to clean and after a while not very sanitary and expensive to replace.

There are two very large open-air windows so slight moisture or temporary dampness is not a worry (I live in a dry area), however, I would like to have some way to channel water off of the surface of the concrete under the gravel when it is hosed off 2 times a month.

And to make things more complicated -
I know very little about concrete or installing drains - I'll probably do more damage with a jackhammer than help.
I would like to find something cheaper than 200 bucks.

I had thought about just drilling some holes where the concrete meets the wood along the sides but I have a felling there is a better solution out there. I found this site when I was googling trying to find an answer. Any good ideas out there?

Thank you!