I would wade carefully into the middle of the stream at a point where the fish aren't, and then slowly work my way upstream casting 20'-35' (to avoid getting too close to spook fish I don't see) to the edges and weed beds. I don't know what flies work best on that particular stream, but based on what I know about another WNY spring creek I might start by trying a scud or a small #20 pheasant tail under a dry beetle or flying ant.