In general, each point shows a numbered ramp along statewide highways, per the direction of the highway (for instance, for a Northbound-Southbound highway, there is one point record for a Northbound exit and one point record for a Southbound exit). The DIR field indicates the directionality associated with the feature. In some cases, a single point may represent both the on- and off-ramp.

Per the Caltrans Trash Assessment Methodology (TAM), 2024 trash generation rates were applied from the Combined Score methodology, where calculated; where the Combined Score was not calculated, the trash generation rate of the applicable adjacent highway segment was applied. Please refer to the most recent TAM for more information on trash generation ratings and their application.

Point locations are as received from Caltrans. Each record is coded with the district, county, and route information, along with postmile prefix (if any), postmile, and postmile suffix (if any), along with the exit number and intersection name. Additional attributes related to stormwater compliance have been added. Refer to the Resource > Lineage and Resource > Fields sections of this metadata for additional details.

This feature layer does not include areas within CA Regional Water Quality Control Board 2 or Los Angeles Trash Total Maximum Daily Loads (TMDLs); for more information on those areas please refer to the California Water Boards website at https://www.waterboards.ca.gov/.