The 2018 RRNW Symposium will feature invited speakers. Our invited speakers and the topics to be addressed are as follows:
Wild Salmon Recovery and Delusional Reality: Indulgences Atoning for Guilt?
Robert T. Lackey
Oregon State University, Department of Fisheries and Wildlife
The history of efforts to reverse the long-term decline of Pacific salmon in California, Oregon, Washington, Idaho, and southern British Columbia provides instructive policy lessons about how many human’s respond to unpleasant realities. From California to southern British Columbia, wild runs of Pacific salmon have declined over the long-term and many have disappeared. Billions have been spent in so-far failed attempts to reverse the decline. The annual expenditure of hundreds of millions of dollars continues, but a sustainable future for wild salmon in this region remains elusive. Despite documented public support for restoring wild salmon, the long-term prognosis for a sustainable future appears problematic, especially toward the southern end of the distribution. Fisheries scientists and others continue to craft restoration plans, but an effective, politically viable approach has yet to emerge that will actually restore and sustain many runs of wild salmon. For wild salmon, restoration options exist that offer both ecological viability and appreciably lower social disruption, but these options also tend to have more modest restoration objectives. Perhaps these billions of dollars being spent to recover wild salmon should be considered “guilt money” — modern-day indulgences — a tax that society and individuals willingly endure to alleviate collective and individual remorse. It is money spent on activities unlikely to achieve the publicly stated goal of recovering of wild salmon, but perhaps it helps many people feel better as we continue the behaviors and choices that essentially preclude their recovery.
Dr. Bob Lackey is professor of fisheries science at Oregon State University. In 2008, he retired after 27 years with the Environmental Protection Agency’s national research laboratory in Corvallis where he served as Deputy Director, Associate Director for Science, and in other senior leadership positions. Since his very first fisheries and wildlife job mucking out raceways in a California trout hatchery, he has worked on an assortment of environmental and natural resource issues from various positions in government and academia. His professional assignments involved diverse and politically contentious issues, but mostly he has operated at the interface between science and policy. He has published over 100 articles in scientific journals and is a fellow of the American Fisheries Society and the American Institute of Fishery Research Biologists. Dr. Lackey has long been an educator, having taught at five North American universities and currently teaches a graduate course in ecological policy at Oregon State University. Canadian by birth, he is now a U.S.-Canadian dual-citizen living in Corvallis, Oregon.
Restoring a wetland/floodplain landscape buried beneath reservoir sediment for 3 centuries: The long-term Big Spring Run restoration experiment and a new best management practice
Dr. Dorothy Merritts
Department of Earth and Environment
Franklin and Marshall College
The headwaters of Big Spring Run (BSR), a 3nd-order agricultural watershed in southeastern Pennsylvania, is the site of a long-term restoration experiment designed to develop and test a new best management practice based on eco-hydrological restoration. The site was selected in part because it is located in the Piedmont Physiographic Province, which has the highest nutrient and sediment yields in the Chesapeake Bay watershed. Our research throughout this region indicates that a large portion of suspended sediment in streams is historic and anthropogenic in origin, much of it trapped behind tens of thousands of dams (typically less than 5 m high) that were built to power ubiquitous mills during the late 17th to early 20th c. First, 2nd, and 3rd-order streams (~90% of watershed area) were heavily impacted, with mill dam density as high as one per 2 km of stream length. Widespread damming coincided with equally widespread land clearing and upland soil erosion. We have dubbed the consequence of this multi-century anthropogenic erosion and sedimentation event the “Pompeii effect”.
As obsolete mill dams breach, this sediment, referred to as “legacy sediment” because of its historic origin, is released via channel incision and bank erosion. Modern streams typically have 2 to 5 m high banks of eroding historic sediment along their length, and sediment loads from these banks remain as high as ~200 tons/km of stream length for decades after dam breaching. Addressing such a widespread impact with enormous changes to hydrologic systems is daunting, but crucial to challenges such as reducing high sediment loads to impaired water bodies (e.g., the Chesapeake Bay) and sedimentation in modern reservoirs (e.g., the Conowingo dam in Maryland). It also is highly relevant to management of aging dams, decisions about how (or whether) to remove them, and the need for storm water retention during urban and suburban development.
We began a long-term investigation with extensive monitoring in 2008 to test the effectiveness of a new valley bottom restoration strategy for reducing surface water sediment and nutrient loads. The overarching approach was to unbury the pre-Colonial landscape and re-establish a wetland ecosystem similar in function to that which existed prior to valley bottom inundation and sedimentation. Our fundamental hypotheses were that 1) removal of legacy sediments will reduce sediment and phosphorus loads, 2) the eco-hydrological functions of a buried Holocene wetland-floodplain system can be recovered by exhumation (Walter & Merritts 2008), and 3) removal of sediment and return to wetland conditions will improve surface and groundwater quality by creating accommodation space to trap sediment and carbon and therefore to enhance nutrient processing. Sediment removal (~20,000 tons) occurred in late 2011, and wetland planting during May 2012. The silt-rich legacy sediment was used for brownfield redevelopment at a nearby post-industrial site.
Comparisons of pre- and post-restoration gage data at Big Spring Run show that restoration lowered the annual sediment load by at least 118 t yr-1, or >75%, from the 1000 m-long restoration reach, with the
entire reduction accounted for by legacy sediment removal. Repeat RTK-GPS surveys of pre-restoration stream banks verified that >90 t yr-1 of suspended sediment was from bank erosion within the restoration reach. Chemical fingerprinting indicates that 85-100% of both the pre-restoration and post-restoration suspended sediment load was from stream bank sources. This is consistent with trace element data which show that 80-90 % of the pre-restoration suspended sediment load at BSR was from bank erosion.
We conclude that 1) upland farm slopes contribute little soil to the suspended sediment supply within this study area, even though it plays a dominant role in watershed models of sediment sources, and 2) removal of historic valley bottom sediment effectively reduced bank erosion and sediment and phosphorus loads. Enhanced deposition after wetland exhumation further contributed to load reductions; prior to restoration, there was no deposition on tile pads on the 1.5 m-high legacy sediment “floodplain” terrace, whereas after restoration deposition on the low, restored floodplain showed net accumulation of 0.009 ± 0.012 m yr-1. Finally, wetland-floodplain restoration resulted in multiple shallow branching stream channels, substantially cooler water as a result of reconnecting the floodplain with shallow groundwater sources, and new colonization of the green frog.
Dorothy Merritts/The Harry W. & Mary B. Huffnagle Professor of Geoscience, Department of Earth and Environment at Franklin and Marshall College
Dorothy Merritts is a geomorphologist with a research focus on the impact of geologic processes, human activities, and climate change on the form and history of Earth’s surface, and makes extensive use of airborne and ground based lidar in her investigations. With collaborators at multiple institutions and many state and federal agencies, she is developing and testing new methods of wetland, floodplain, and stream restoration that rely upon geomorphic investigation and understanding of landscape processes and history. She and her group established the long-term aquatic wetland/floodplain restoration project at Big Spring Run in Pennsylvania, which has more than 8 years of pre- and post-restoration monitoring data (www.bsr-project.org). She is a co-founder and lead scientist at The Water Science Institute and currently President-Elect of the American Geophysical Union Earth and Planetary Surface Processes Group.
Restoring the Lower Snake River: Vision, A Mountain of Policy Horsepower and Two D8s
For the last 50 years the lower Snake River has not been a river at all, but a 140-mile string of stagnate reservoirs sitting behind four dams built by the US Army Corps of Engineers. These four dams have never been economically justifiable for either inland water navigation to Lewiston, Idaho or for Hydropower. Indeed today, they are the financial millstone around the neck of the Bonneville Power Administration and its ratepayers that all but guarantees the insolvency of the Federal Columbia Hydro system in the not-to-distant future. River restoration is as much about fish as it is about saving large sums of money.
One of the powerful considerations for a restoration project like this, unlike many others which are done within the constraint of existing infrastructure like levees, roads, buildings etc., is that there is almost none of this infrastructure to deal with once the reservoirs are removed. The river corridor is returned to a near pre-Columbian state. Ninety percent of the restoration is complete simply by draining the reservoirs. This can easily be accomplished with a controlled hydraulic breach after notching the earthen portion of the dams. Working with natural hydraulic and sediment deposition processes, via a limited amount of adaptive construction, does the rest. This presentation will also cover how breaching, channelization features around the dams, and riparian restoration can be done at a 70% cost savings over the plan developed by the Corps.
So, lower Snake River restoration is much more a policy and funding issue than a technical one. And like most river restoration projects, especially ones of this scale, it involves a vast group of diverse stakeholders. In the case of the lower Snake River dams, rational analysis of the environmental, economic, and social pro and cons of restoration have, over many decades, morphed into an intractable process defined by narrowly evolved arguments between constituent groups or camps. This has all come at the expense of the many. Breaking the arguments open with a new narrative and allowing the many to see a vision of what a restored river looks like in terms of biological abundance, economic vibrancy, and social well being, are all a key part of accomplishing the restoration. The restoration is not just an undoing of infrastructure. It is also the reconnection of people, place, and relations that needs to be celebrated as a key element of the new narrative leading into the restoration that also integrates natural and human values needed for long term resiliency over time.
Jim is a Civil Engineer who retired from a 35 year career with the Army Corps of Engineers. For over twenty years of that career he has been a leader in developing the policies and practice of Sustainable Development within the Federal family. In 1999, Mr. Waddell became the Deputy District Engineer for Programs at the Walla Walla District at the time the Lower Snake Feasibility Study was into its 5th year of development. This study was the most comprehensive ever under taken to determine the feasibility of breaching dams to restore salmon runs. After retirement from the Corps in 2013 he has undertaken a reevaluation of the study and his work shows that the magnitude of cost errors in the report shows that breaching the 4 Lower Snake Dams is not only a sound biological choice but will prevent the waste of millions of taxpayers dollars.
In 2001, the US National Research Council report on Basic Research Opportunities in the Earth Sciences proposed the term “critical zone” to describe a region of the earth that extends from the vegetation canopy to the “base of the groundwater zone”. The term “critical” was assigned to this zone to emphasize that it “sustains nearly all terrestrial life”. The base of the critical zone then was conceptual, as it is difficult to assign an absolute boundary across the terrestrial earth below which no meteoric water travels. As the critical zone concept became translated into US National Science Foundation-supported Critical Zone Observatories a narrower, simpler definition emerged that is applicable to many landscapes: the thin veneer of Earth that extends from the top of the vegetation to the base of weathered bedrock. With this definition we can envision the critical zone as a distinct entity with a well-defined top and a fairly well-defined bottom. It is a zone of co-evolving processes and, importantly, much of this zone is well below the soil mantle. Weathering advance into bedrock creates a hydrologically-conductive skin that mediates runoff and solute chemistry, stores water used by vegetation, influences soil production and hillslope evolution, and feeds gasses to the atmosphere. In essence, we can now see hillslopes as reactive filters through which watershed currencies (water, gasses, sediment, biota, solutes, energy and momentum) are mediated. The critical zone is commonly 10 times thicker than the soil mantle. But the spatial structure of the critical zone is still poorly known.
In seasonally dry environments, we have found that rock moisture, i.e. moisture that is exchangeable and potentially mobile water in the matrix and fractures of the weathered bedrock of the critical zone, can be a significant source of moisture to plants and a large component of the water budget. This moisture is not included in regional or global climate models. We are now debating whether rock moisture use in the summer by trees influences baseflow. This is key forest management question.
Summer baseflow is derived from groundwater drainage from the critical zone. In the northern California Coast Ranges critical zone structure strongly depends on characteristics of the underlying bedrock. In the Coastal Belt of the Franciscan formation (mostly shale and sandstone) which underlies the Angelo Coast Range Reserve, the critical zone thickness exceeds 25 m at hilltops and ~300 mm of annual precipitation (about 2000 mm) is seasonally stored as rock moisture. A seasonal groundwater table develops on the underlying fresh bedrock and slowly drains via fractures to springs that mostly remain flowing throughout the summer, sustaining salmon populations. A dense, mixed evergreen forest dominates the vegetation. Just 20 km away the landscape is underlain by the Central Belt of the Franciscan formation, which is mélange (intensely deformed shale with blocks of sandstone and many other rock types mixed into it). Here the critical zone is less than 3 m thick, winter runoff occurs as saturation overland flow, rock moisture storage is small, and the dominant vegetation is grass. The only springs come from the sandstone blocks and in smaller watersheds there is no summer baseflow. The springs from the sandstone blocks are now being exploited for marijuana production, threatening local ecosystems and base flows of larger watersheds.
Critical zone structure strongly influences terrestrial and river ecosystems. Research is advancing theory and observation for explaining and predicting the structure and how it mediates watershed currencies.
William E. Dietrich became a professor in the Department of Earth and Planetary Science at UC Berkeley in 1982 after completing his PhD dissertation work on river meander mechanics at the University of Washington. He is a geomorphologist who has worked on hillslope and fluvial processes and contributed to some 250 papers on such topics as sediment budgets, soil production and transport, weathering, landsliding, debris flows, runoff processes, weathering, river incision into bedrock, gravel transport, river meandering, floodplain deposition, channel networks, landscape evolution, and surface processes on Mars. He is co-founder of the NSF supported National Center for Airborne Laser Mapping and Director of the Eel River Critical Zone Observatory.