You need a rotary level and figure out where you can let that water out, Unless it obvious with your eye. Looking at your picture, I would dig a trench around the build and go through the driveway, and let it out somewhere or into another drainage ditch. You could also tie your gutters into that also. I would take grade sticks a put them every 10 ft and figure out the available pitch and lay it out before he comes in with the excavator. have him dig it while you work the level and it probably wont be more than a two hour dig.