Compartmental Analysis of Nutrient Processing in Streams

Background

Previous work under this project focused on developing a screening-level
model of nitrate attenuation in streams. The work was based on the
premise that stakeholders often are not concerned about nitrate transport
and reaction; instead, stakeholders were focused on the total amount of
retention or attenuation that a particular hydrologic compartment can
produce (Faulkner and Campana 2007). This modeling approach has been
brought into a Bayesian framework with potential application for adaptive
management of nutrient total maximum daily loads (Faulkner 2008). In a
relatively empirical way, these modeling approaches have treated ground
water surface water interactions (hyporheic flow) with transient storage in
dead zones.

We have done work to develop methods for quantifying the actual
hyporheic component (Faulkner, et al. 2005). The hyporheic component is
known to be important in the retention of nutrients. Current work under
this project is linked to another project examining denitrification potential
in the Willamette River floodplain. That work is focused on using
numerical ground water flow modeling to develop conceptual models of
ground water-surface water interactions in the Willamette River Floodplain
Oregon.

Products

Faulkner, B.R. (2008). "Bayesian Modeling of the Assimilative Capacity Component of Nutrient Total Maximum
Daily Loads/' Water Resources Research, 44: W08415. doi: 10.1029/2007WR006638.

Faulkner, B.R. and M.E. Campana. (2007). "Compartmental Model of Nitrate Retention in Streams.'" Water
Resources Research, 43: W02406. doi: 10.1029/2006WR004920.

Faulkner, B.R., V.A. Murray, and S.R. Hobson. (2005). "'Use of Electrical Resistivity Probe for Determination of
Hyporheic Flow." In: Proceedings American Water Resources Association 2005 Annual Water Resources
Conference, Seattle, Washington, November 7-10. Edited by C. Steward. American Water Resources Association,
Middleburg, Virginia, TPS-05-3, CDROM.

Principal Investigator	Collaborators

Bart Faulkner	McKenzie River Trust

580 4j6 8530	Tishomingo National Wildlife Refuge

U.S. EPA

National Health and Environmental Effects
Laboratory, Western Ecology Division

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