BES SOTR progress measure info request

The percentage of sampled stream sites rated as severely impaired, marginally impaired, or acceptable for fish habitat using an index of biotic integrity every 3-5 years. (See note a.)

The change in water quality at select stream and Willamette River sites which are monitored by DEQ. (See notes b and c.)

The concentration levels of E. Coli in the Willamette River. (See note d.)

[Note: in 2007 we reported info on the Willamette at the Hawthorne Bridge]

a.  The index of biotic integrity, or IBI, reflects functional aquatic components of an ecosystem: aquatic species richness and composition, number and abundance of indicator species, trophic organization and function, reproductive behavior, and condition of individual organisms. “Biotic integrity” is often used to evaluate the effects of humans on native fish. It is defined as the ability to support and maintain a balanced, integrated, adaptive community of organisms that have a composition, diversity, and functional organization comparable with that of the natural habitat or region. This biotic integrity measure will need to be modified for the lower Willamette River because there are no “natural,” or undeveloped examples with which to compare the lower Willamette.

b.  Many factors beyond Portland’s control influence the quality of water and the quality of fish habitat in the Willamette River. Many sources of pollutants are upriver of Portland. The timing and volume of rainfall influences results as well.

c.  The Oregon Water Quality Index (OWQI) analyzes a defined set of water quality parameters and produces a composite score describing general water quality. The water quality parameters included in the OWQI are temperature, dissolved oxygen (percent saturation and concentration), biochemical oxygen demand, pH, total solids, ammonia and nitrate nitrogens, total phosphorous, and fecal coliforms. Index scores range from 10 (worst) to 100 (best). The water quality index has limitations. An index provides only a summary of the data. But, the index allows users to easily interpret data and relate overall water quality variation to specific categories of impairment. The index can identify water quality trends and problem areas. It cannot determine the quality of water for all uses or all health hazards.

d.  Portland’s Combined Sewer Overflow (CSO) Abatement Program will significantly reduce bacteria levels by 2006, when the West Side Big Pipe is completed. Another drop in bacteria levels is expected to occur in 2011 when the East Side CSO Tunnel is completed.

In addition, any empirical or anecdotal information that conveys what BES believes to be a possible trajectory (like native fish showing up rapidly after a restoration project) is also welcome.