Potamopyrgus antipodarum is an aquatic invader known to cause ecological harm. Population densities of these snails have not been determined in PA. In this study, we sampled sites in the Spring Creek watershed in May and July 2022. To determine density, we used a stovepipe sampling technique. We measured each snail and assessed reproductive efforts. Preliminary data suggests that the snails exist in the thousands per square meter. Potamopyrgus appears well established in Spring Creek.