Microplastics are a major environmental issue of concern that affects all waterways. However, limited research has been conducted to determine the severity of microplastics specifically in the Lower Hudson River Estuary (LHRE). Since 2016, Hudson River Park has collaborated with Brooklyn College to survey microplastics within Park waters, between Chambers Street and 59th Street in Manhattan, New York. It was hypothesized that microplastic concentration is influenced by proximity to combined sewer outfall (CSO). The Park's microplastics study additionally aimed to understand how microplastic concentration is influenced by precipitation, and the semidiurnal tidal cycle. Samples were collected at channel and near-shore locations at both downtown and midtown sites. Microplastics were counted and categorized based on plastic type using a stereo microscope. Statistical analyses revealed that concentrations from 2018 varied significantly from all other years (p