The City of Austin conducted a spatially robust field survey to understand distribution and sources of trash in creeks. Data points were collected every 30ft for a total of 19,467 observations in 110 miles along 20 creeks from November 2021 to April 2022. Spatial (GIS) analysis and linear regression, at the raw data level and aggregated, were used to evaluate relationships between trash intensity and observed point sources such as overflowing dumpsters, illegal dumping, historic dumping, encampments, as well as physiographic attributes such as population, transportation, and land use (e.g., single family residential, multifamily, commercial, parks, etc.). Surprisingly, there were no strong relationships with any of the sources or watershed attributes. Results show that trash intensity does not correlate well with stream position (i.e. upstream-to-downstream) and trash does not move evenly through the system which complicates efforts to quantify the relative impact of different sources. Presence of trash appears more strongly influenced by stream roughness (primarily riparian vegetation) than by source inputs which presents an opportunity to use these natural “strainers” as locations to periodically remove trash from the system. Spatial analysis indicates that 76% of the total volume of trash was located at only 10% of the observation points. The most encountered items were single use plastic beverage and food containers resonating a global appeal for reduction. This study, although specific to Austin, developed a novel field method whose results are very relevant to any cities that would like to start understanding urban watershed trash dynamics.