Click on the links below for background information about the Willamette Water 2100 project.
The Willamette River Basin in western Oregon spans nearly 12,000 square miles (30,000 square kilometers), from its snowy, forested headwaters in the Oregon Cascades to its green valley floor. It is home to 70% of Oregon’s population, and provides water for the region's diverse ecosystems and economy. Currently, the Willamette River Basin is water-rich, but with a warming climate and increasing socio-economic pressures that may not always be the case. Such pressures raise a number of important questions:
Will we have enough water to satisfy future needs?
Where, when and under what conditions might water scarcity emerge in the coming decades?
What policy actions might reduce the potential for water scarcity?
These questions motivated the Willamette Water 2100 project (WW2100), a collaborative research project led by faculty from Oregon State University (OSU), the University of Oregon (UO), Portland State University (PSU) and the University of California-Santa Barbara. The project was funded by the National Science Foundation and the National Oceanic and Atmospheric Administration and ran from October 2010 through September 2016.
The primary project objectives were to:
identify and quantify the linkages and feedbacks among human, hydrologic, and ecologic dimensions of the water system,
make projections about where and when human activities and climate change will impact future water scarcities,
evaluate how biophysical and human system uncertainties affect these projections, and
evaluate how policy changes or other interventions might affect future water scarcities.
We recognize that the Willamette River Basin is a complex coupled system, one that includes both a natural system (the biophysical components) and a human system (the socio-economic components). The interactions, feedbacks, and evolving characteristics of these different components will control when and where water is abundant or scarce. Modeling such a system has to be selective: it would be impossible to model all aspects of such a complex system in great detail and high resolution. We therefore chose to focus on the elements, relationships, and feedback mechanisms that were most important to the key objectives described above. Fig. 1 describes at a general level the main components of the Willamette River Basin that we modeled in detail. The components include “external drivers” (factors outside the control of people in the basin), including the climate, population growth, and growth in income levels. This conceptual model identifies components related primarily to water supply and demand. Water supply is mainly determined by the biophysical system. Water demand includes human demands for water that are both direct (urban use) and indirect (water allocated by law to protect fish). At a general level, human decisions influence how land and water is used as a result of laws, regulations, and policies, and these in turn influence how individual decisions are made (farmers, consumers), and how society’s representatives (public officials) act to allocate land and water (e.g., reservoir management).
Figure 1. Conceptual diagram of the Willamette water system showing the human and natural system elements that Willamette Envision represents.
Given the complexity of the system, and the detailed spatial and temporal scales at which these different components interact and influence each other, an explicit and quantitative representation of this system requires a computer model to incorporate the many processes and relationships in time and space between and among the natural and human system components, so that we are able to predict how those processes are likely to change over time. As a result, we developed Willamette Envision, a computer model that includes sub-models for each of the biophysical and economic components indicated in Fig. 1. The model captures key biophysical and socioeconomic elements of the system that allow us to address the first two objectives. In addition, the model can be used to ask “What if?” questions of interest to applied scientists, policymakers, and the general public. These questions explore the interactions between land and water use, law and policy, and public management of land and water resources. A more detailed description of Willamette Envision is contained in the model overview section.
As a companion to the project’s scientific publications, this website provides an overview of project methods and findings, and a portal to access publications, data products, and unpublished project materials. It also contains sections describing the project’s broader impacts activities such as engagement with regional stakeholders, and training provided to university students and K-12 students and teachers. This website is intended for use by scientists, water and land managers, policy and decision makers, and educators.
The Willamette River flows north, draining 29,728 square kilometers (11,478 square miles) of diverse landforms and ecology. To the east, High Cascades volcanoes create the basin’s headwaters, with alpine peaks ranging up to 3,426 meters (11,239 feet). To the west, weathered volcanic and sedimentary rocks of the Coast Range bound the basin. Coniferous forests predominate in both mountain ranges and cover about 70% of the basin. Agriculture and city landscapes predominate in the Willamette Valley, with many cities including Eugene, Salem, and Portland clustered along the Willamette River mainstem. The basin’s river systems are home to diverse aquatic species including 36 native fish species, seven of which are listed by the federal or state government as species of concern.
Figure 1. Shaded relief map of the Willamette River Basin, looking to the west and the Pacific Ocean. Image credit: Charles Preppernau, OSU. Photo credits (left to right): Al Levno, OSU, USACE.
Seasonal patterns strongly influence water supply and demand in the Willamette River Basin. Winters are cool and wet with abundant precipitation that swells the rivers, recharges soil moisture and groundwater, and creates snowpack in the basin’s Cascade mountain headwaters. In contrast, summers are warm and dry, with little precipitation to meet the warm-weather water demands of forests, agriculture, and cities. A system of 13 federal reservoirs managed by the U.S. Army Corp of Engineers (USACE), called the Willamette Project, also exert a strong influence on hydrology by reducing winter flood peaks and augmenting summer flows in the Willamette River mainstem and major tributaries draining the Cascade mountains. The reservoirs were built primarily to reduce flooding in the Willamette Valley, however they also serve other purposes such as power generation, recreation, and water supply for irrigation. Interest in the reservoirs as a water supply source has grown in recent years, and in 2016 the USACE and Oregon Water Resources Department re-initiated a study to consider how stored water is allocated for summer water needs.
Figure 2. Mean monthly precipitation in the Willamette Basin.
Project researchers and Learning and Action Network team members gathered in Salem in December 2015 for a capstone workshop. Photo credit: Kayla Martin, OSU
Beginning in project year 5 (fall 2014), we invited a core group of 25 citizen stakeholders to participate in a series of meetings to define the assumptions for two stakeholder scenarios and provide feedback on communicating project findings. TAG members included:
Throughout the project, the science team met with regional water managers, stakeholders, and educators. This group was called the Learning and Action Network (LAN) and grew to include county commissioners, managers, and scientists from state and federal natural resource agencies, farmers, K-12 educators, and representatives from water utilities, conservation organizations, and industry. Over 120 people participated in at least one LAN event over the project's six years. LAN events consisted of fieldtrips, workshops, and webinars, where we encouraged dialogue about water issues in the basin and introduced and received feedback on WW2100 modeling approaches and analysis.
The goal of the Willamette Water 2100 project was to develop tools and understanding that will help anticipate water scarcity and inform integrated water system management. Here we highlight some of the key outcomes from the project:
Some of the unique aspects of the model include:
Related findings:
Related findings:
Related findings:
The project was affiliated with the NSF Water Sustainability and Climate (WSC) program, an effort to enhance understanding of the Earth's water system and interactions between human activity, climate change, and ecosystem functions. NSF's WSC program supported place-based modeling projects at universities across the United States. The OSU Institute for Water and Watersheds provided administrative support for the project, and the Institute for Natural Resources assisted with data management.
Any opinions, findings, conclusions or recommendations expressed on this website are those of the authors and do not necessarily reflect the views of the National Science Foundation or the National Oceanic and Atmospheric Administration.
Dr. Anne Nolin, Professor
College of Earth, Ocean, and Atmospheric Sciences
Oregon State University
Phone: 541-737-8051
Email: [email protected]
Maria Wright, Faculty Research Assistant
Institute for Water and Watersheds
Oregon State University
Phone: 541-737-6148
Email: [email protected]
This website is a companion to the project’s scientific publications, and provides an overview of project methods and findings, and a portal to access publications, data products, and unpublished project materials. It also contains sections describing the project’s broader impacts activities such as engagement with regional stakeholders, and training provided to university students and K-12 students and teachers. Most of the material on this site was developed in 2015 and 2016 by the WW2100 research team and was edited by Maria Wright, Anne Nolin, and Abby Metzger. The technical sections (under "Analysis by Topic") were written by subject matter experts - refer to the "more information" tab of each section for author name(s) and posting date.