While the health of our creeks is very much influenced by human activities in the uplands of our watershed, creeks have their own dynamics that have a direct relationship with their immediate human neighbors. Thanks to the tradition that property boundaries generally run down the center of the creek, waterways are usually not bridged over or otherwise developed beyond what is necessary to protect real estate (or to accommodate public roads). The result is that creek corridors are—or have the potential to be—nature reserves in the heart of the heavily developed valley floor.