Testing the creek is a good idea. I can phone the cooperative extension on Monday and see if they do water testing. Maybe they do.
The toads were in the hundreds and were here for decades no matter if we had a wet or dry spring so maybe your suggestions to focus on the water is the way to go. That does make sense seeing as the trees are also by the water. hmmm. Think I'll put on some long pants (ticks still around) and check around the rocks in the creek.
Thanks. Will check on the lizard population while I'm there.