samples), and monthly during 2006 (mid-depth samples). Additional water samples were collected for 
total suspended solids (TSS) analysis. 
Light attenuation coefficients (kj) were determined for each station as the slope of the regression 
of In (PAR) vs. depth for the 1.00 m to 3.75 m depth intervals. Many of the light profiles measured 
during the cruises were conducted during flood tides; therefore, the light attenuation coefficients may 
be biased toward clearer flood tide conditions. In addition to the cruise data, PAR was monitored 
continuously with 15 minute averages recorded at five locations in the estuary (WED unpublished 
data). Three of these sites were in Zone 1 (located 3.7, 3.9, and 9.0 km from the mouth of the estuary) 
and two were in Zone 2 (located 18.4 and 16 km from the mouth of the estuary). Measurements at 
these sites were taken nearly continuously from 1999 through 2003 using two PAR sensors placed 0.75 
m apart in depth, which were used to calculate light attenuation coefficients. The sensors were cleaned 
at one to two week intervals. For the analyses presented in this document, we used attenuation 
coefficients measured at local noon time and within 4.5 days of cleaning for the continuous data set. 
Additional high temporal resolution data were collected at the riverine and oceanic boundaries to 
quantify the oceanic and riverine inputs of dissolved inorganic nutrients and chlorophyll a to the 
estuary. Continuous data (including water temperature, salinity, dissolved oxygen, and in situ 
fluorescence at 15-min intervals) from YSI multiparameter sondes (YSI 6600 EDS, YSI Inc., Yellow 
Springs, OH) were available at approximately six locations in the estuaries (with the exact number of 
locations depending upon the year and month). 
4.1.2 Additional Data Sources 
A summary of historic data compiled for the Yaquina Estuary is provided in Table 4.2. In 
addition to the sources listed in Table 4.2, data were obtained from the Oregon Department of 
Environmental Quality Laboratory Analytical Storage and Retrieval (LASAR) database 
(http://deq 12.deq.state.or.us/lasar2/) , which included data for 27 sampling locations and spanned the 
time interval of 1960-2005. 
There was a gap in the data for causal and response variables during the interval of 1984-1997. 
The majority of the nutrient data was in the form of dissolved inorganic nutrients rather than total 
nitrogen or phosphorous. Most of the data compiled was collected at fixed sampling locations, rather 
than through probabilistic sampling. All the data were collected along the main channel of the estuary, 
and did not extend into the sloughs. The locations of stations sampled extended trom the mouth to the 
fi¬ 
ll 
