Preface 
Disclaimer 
The information in this document has been funded wholly by the U.S. Environmental Protection 
Agency. It has been subjected to review by the National Health and Environmental Effects 
Research Laboratory and approved for publication. Approval does not signify that the contents 
reflect the views of the agency, nor does mention of trade names or commercial products 
constitute endorsement or recommendation for use. 
Citation 
Brown, C.A., W.G. Nelson, B.L. Boese, T.H. DeWitt, P.M. Eldridge, J.E. Kaldy, H. Lee II, J.H. 
Power, and D.R. Young. 2007. An Approach to Developing Nutrient Criteria for Pacific 
Northwest Estuaries: A Case Study of Yaquina Estuary, Oregon. USEPA Office of 
Research and Development, National Health and Environmental Effects Laboratory, 
Western Ecology Division. EPA/600/R-07/046. 
Acknowledgements 
We greatly appreciate the assistance of numerous employees of Dynamac Inc. who 
provided technical support to Western Ecology Division (WED) for many aspects of the work 
described in this document, including Adam DeMarzo, Lucas Nipp, Stacy Strickland, and Una 
Monaghan. We appreciate the administrative support provided by Janet Lamberson (WED). 
Gary Arnold with the Oregon Department of Environmental Quality (ODEQ) provided helpful 
review comments on this document as well as information on water quality standards and 
historical information. Tim McFetridge (ODEQ) and Lee Ritzman (Public Works Department, 
City of Newport) provided information on point source inputs. Deneb Karentz (University of 
San Francisco) kindly provided some unpublished historical data. Anne Fairbrother, Marilyn ten 
Brink, Robert Ozretich, and James Hagy provided comments on the manuscript which improved 
the quality of the report. Numerous WED staff contributed unpublished data to this report, 
including Bruce Boese (Z. marina lower margin and macroalgae), Cheryl Brown (water quality), 
Pat Clinton (maps of Z. marina and macroalgae coverage), Ted DeWitt (macroinvertebrate and 
benthic flux), Peter Eldridge (water quality), James Kaldy (Z marina and stable isotope), Henry 
Lee (watershed landscape), Walt Nelson (epiphyte data), Robert Ozretich (cruise and irradiance), 
David Specht (datasonde), and David Young (macroalgae and Z. marina data). 
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