As part of the city’s stormwater management program, the Portland Area Watershed Management and Assessment Program (PAWMAP) measures water quality, habitat, and biological conditions in Portland’s watersheds to determine the effectiveness of stormwater management controls and regulatory compliance. Presence and abundance of fish are important indicators of watershed conditions.

An overwhelming majority of the fish species found in Portland area waterways are native to this region.

Total number of fish captured (left) and the frequency of detection
(number of surveys at which each species was captured).

Data collected July 2010-June 2011