2007-08 SOTR Council Presentation Resource Sheet

 

from DEQ (http://www.deq.state.or.us/lab/wqm/wqindex.htm)

 

The Oregon Water Quality Index (OWQI) is a single number which expresses water quality by integrating measurements of eight carefully selected water quality parameters:

❑  temperature

❑  dissolved oxygen

❑  biochemical oxygen demand

❑  pH

❑  ammonia+nitrate nitrogen

❑  total phosphates

❑  total solids

❑  fecal coliform

 

The index was developed for the purpose of providing a simple, concise and valid method for expressing the significance of regularly generated laboratory data, and was designed to aid in the assessment of water quality for general recreational uses.

 

The OWQI cannot provide complete information on water quality. An index provides only a summary of the data. Also, the OWQI cannot evaluate all health hazards. The OWQI can be used to show water quality variation both spatially and temporally. The index allows users to easily interpret data and relate overall water quality variation to variations in specific categories of impairment. The OWQI can identify water quality trends and problem areas.