This data release contains cyanotoxin concentrations for microcystins, cylindrospermopsins, anatoxins, and saxitoxins assessed using Enzyme-Linked Immunosorbent Assays (ELISA) on 363 samples collected from 82 surface-water sites located in the Cascade Range in Oregon, and eight sites located outside of the Oregon Cascade Range in Washington and California, during 2016-2020. Three sample types were assessed: 1) benthic colonies and mats of cyanobacteria (n=109), 2) plankton net tows (n=90), and 3) Solid Phase Adsorption Toxin Tracking samplers (SPATTs)(n=164).