Thanks! Maybe you can put some out before work tomorrow to begin with. Just make sure it's not too close to your pens as to attract any pests or predators.
I know where I live a lot of wild ducks know exactly who comes to feed them and at what time, so they wait at that exact time everyday...
Perhaps you can try leaving a little duck food at the water's edge at regular intervals. Other animals may also eat it, but she might find it and anticipate the feedings and wait for you after a little while. Then, you can work from there.
I'm sorry that this happened to you, especially on the first day when she doesn't know the area. I hope she's bonded enough to the male to stick around until you can find her.