10 meter elevation data for Oregon was obtained by the USDA Forest Service for the Coastal 
Landscape Analysis and Modeling Study project (CLAMS, http://www.fsl.orst.edu/clams ) from 
USGS drainage enforced digital elevation models. 
Population Density 
Human population estimates from the 1990 and 2000 censuses (http://www.census.govA 
were generated for the drainage unit. Area weighted estimates of total population by census 
block were summed for each drainage and population density (individuals/sq. kilometer) was 
calculated from the total drainage population estimate. 
Other Data Sources 
Historical sources (data collected in the 1960, 70 and 80’s and presented in technical 
reports, thesis dissertations or journal publications) were carefully reviewed for information on 
quality procedures implemented in their data collection. Methodological approaches for 
measuring DO, chlorophyll-#, and nutrients were reviewed for analytical method utilized. Data 
obtained from the Oregon Department of Environmental Quality database were previously QAed 
and only data with grades of A and A+ were used as part of this report. Often historical data 
collected before the use of GPS systems were given as locations on map, common station names, 
or as kilometers upriver. From these descriptions, the northing and easting UTM locations were 
estimated using Topozone or Google Earth. Locations given in Latitude and Longitude were 
converted into UTM units using a batch converter located at 
http://www.uwgb.edu/dutchs/UsefulData/HowUseExcel.HTM or in Topozone. Units were 
converted to metric units (i.e. feet to meters, Fahrenheit to Celsius, etc.). Most of the data was 
hand entered from tables to electronic format in Excel. Data was entered electronically by one 
person and checked for errors by another independent person. Data points presented only in 
graphical format were digitized into electronic format and translated into tables. Errors and any 
resulting changes were documented and traced to the source. All data were entered into an 
Access database and data were reviewed to ensure that there were no duplicate entries. 
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