A decision‐support framework for dam removal planning and its application in northern California

Environmental Challenges (Elsevier) | May 27th, 2023

Dam removals are occurring more frequently with the rising cost of maintaining aging infrastructure, public safety concerns, and growing interest in river restoration. So

Dam removals are occurring more frequently with the rising cost of maintaining aging infrastructure, public safety concerns, and growing interest in river restoration. So far, most dam-removals have been unsystematic in their approach. Given the several thousand dam removals expected over the coming decades, a systematic approach to plan future dam removals holds potential for aligning and delivering multiple benefits. Despite multi-sector factors driving decision-making, most existing prioritization frameworks tend to operate within single or related disciplines. Here we present a hierarchical, multi-disciplinary decision-support framework to prioritize dam removals based on opportunistic factors (Tier 1), hydro-ecological variables (Tier 2), and socio-cultural considerations (Tier 3). This framework integrates multiple decision criteria under data availability constraints, incorporates value-driven weights, and can be applied to a portfolio of dams at various spatial scales. The final output facilitates the identification of dam removal projects that align opportunistic, environmental, and social benefits. We recommend the application of this framework as a critical first step to identifying high-priority candidates for removal, recognizing that removal decisions will ultimately require detailed feasibility studies and stakeholder engagement. To illustrate its utility, we apply this framework to California’s North Coast region and identify a small number of “good ”candidates to be considered for removal. We conclude with recommendations for filling critical knowledge gaps and advancing systematic dam removal planning in the United States and beyond.

A Perspective on America's Vanishing Streams

Journal of the North American Benthological Society (University of Chicago Press) | March 1st, 1990

The free-flowing nature of streams in the U.S. has been dramatically altered over the past century, especially through construction of dams. The Nationwide Rivers Invento

The free-flowing nature of streams in the U.S. has been dramatically altered over the past century, especially through construction of dams. The Nationwide Rivers Inventory (NRI) estimated a total of 5,200,000 km of streams in the contiguous 48 states, but only 2% (<100,000 km) have sufficient high quality features to be worthy of federal protection status. The future of this dwindling number of high-quality streams is in doubt as proponents of development compete with conservation interests. Hydropower projects are projected to be built well into the future with a large increase in small projects (55% more than in 1988) even though the total generating capacity of the U.S. would increase only 0.3%. On the other hand, conservation efforts have resulted in increasing levels of federal protection of streams since the 1960s. "National River" or "Wild and Scenic River" status now provides protection for almost 16,000 km of streams, but only about 10% are found east of the Mississippi River. Analysis of the NRI database showed that the greatest quantity and density of high-quality streams are found in the south-Atlantic states, where streams have the least protection. The greatest number of NRI streams are found in the Coastal Plain and Central Lowland physiographic provinces. The NRI analysis showed only 42 high-quality, free-flowing (no major dams) rivers >200 km remaining in the 48 contiguous states. With continuing threats of exploitation, major conservation efforts are required to preserve these last free-flowing streams.

A Spatial Hedonic Analysis of the Housing Market around a Large, Failing Desert Lake: The Case of the Salton Sea in California

Journal of Environmental Planning and Management (Taylor & Francis) | March 2nd, 2018

Many lakes around the world exhibit acute environmental stress due to water transfers, persistent droughts, and polluted runoff. In addition, falling water levels worsen

Many lakes around the world exhibit acute environmental stress due to water transfers, persistent droughts, and polluted runoff. In addition, falling water levels worsen air quality by exposing desiccated shores. To our knowledge, however, no published hedonic study has analyzed the costs of deteriorating water quality jointly with the air quality impacts of falling water levels for a large inland water body. We conduct such an analysis for the Salton Sea, the largest lake in California. Our spatial autoregressive models estimated on single-family properties located within 10 miles (16.1 km) of the Sea show that a 1 km reduction in distance to the Sea results in a $595 decrease in the price of a single-family residence. In addition, a 1% increase in annual particulate matter concentration reduces the value of the average family residence by $1,140. These results highlight the vulnerability of poor rural communities to deteriorating environmental conditions.

Amoral Water Markets?

Georgetown University | June 15th, 2023

Severe water scarcity in the western United States is prompting legitimate questions about the best way to decide which places, people, industries, and species need it mo

Severe water scarcity in the western United States is prompting legitimate questions about the best way to decide which places, people, industries, and species need it most. Water markets, which allow for trading water like a commodity, are perennial proposals during times of scarcity. Water markets have an innate allure: promising to efficiently reallocate water to the highest value uses, minimize risk, and preserve the environment, while relying on the invisible hand to brush aside politically painful values-based questions. This view portrays markets as an amoral arbiter of the best use of water. But water markets are not amoral; they express the historic value judgments baked into the existing western water law system, and layering market approaches over the existing system will both exacerbate the negative impacts of those values and further entrench existing law. In this Article, we show that the West is not ready for water markets.

An Innovative Scheme to Confront the Trade-Off Between Water Conservation and Heat Alleviation With Environmental Justice for Urban Sustainability: The Case of Phoenix, Arizona

American Geophysical Union (AGU) | February 17th, 2023

Anticipating responses to climate change and planning for resilience in California’s freshwater ecosystems

National Academy of Sciences (NAS) | July 29th, 2024

Better late than never: a synthesis of strategic land retirement and restoration in California

Ecological Society of America (Wiley) | August 10th, 2018

Strategic retirement and restoration of agricultural lands is a critical conservation opportunity globally. The objective of this synthesis was to examine whether ecolog

Strategic retirement and restoration of agricultural lands is a critical conservation opportunity globally. The objective of this synthesis was to examine whether ecological habitat assessments, endangered species historical occurrence data, and restoration research can be used to develop evidence-based strategy for retiring and restoring agricultural lands. The San Joaquin Desert (SJD) of California is a prominent example because it experienced an extensive conversion to agriculture. Now, new groundwater regulations will lead to retirement on large areas of agricultural lands over the next 20 years. This presents an opportunity to not only restore some of these lands but also explore the challenges associated with balancing direct human needs with other ecosystem-level functions. California is thus an ideal case study for globally rethinking context-specific, single-case study solutions. We used a systematic review and synthesis to address the following three main questions for habitat recovery of endangered species in the SJD. (1) What are the habitat requirements for key endangered animal species in the region? (2) Is there historical evidence to support an assessment of suitable habitats for these species? (3) What restoration techniques apply to these species? Using the Web of Science and other resources, we reviewed over 1000 independent studies on this topic, refined the evidence, and selected a total of 266 relevant publications. Habitat requirements for each species were described, but there was a critical need to examine quantitative thresholds for these factors to better evaluate habitat suitability of retired lands. There was sufficient evidence of historical vegetation to model suitable habitats and design the physical restoration of retired lands. Direct interventions associated with restoration strategies have been infrequently tested. Sparse and diverse evidence associated with direct experimental manipulations is not uncommon in applied ecology, and synthesis is an excellent tool for highlighting these gaps for future research to examine. This review suggests that retired agricultural land is a viable asset for threatened and endangered species, but to effectively advance restoration research and management, direct tests of restoration techniques and an assessment of relative costs for interventions are needed for a given region.

Bioaccumulation of Pollutants in California Waters: A Review of Historic Data and Assessment of Impacts on Fishing and Aquatic Life

San Francisco Estuary Institute (SFEI) | October 24th, 2007

This report was written for the State Water Resources Control Board’s Surface Water Ambient Monitoring Program (SWAMP) as a step toward the development of an im

This report was written for the State Water Resources Control Board’s Surface Water Ambient Monitoring Program (SWAMP) as a step toward the development of an improved bioaccumulation monitoring program for California. The report provides a review of bioaccumulation monitoring data generated under three historic State Board programs (the Toxic Substances Monitoring Program, the State Mussel Watch Program, and the Coastal Fish Contamination Program) and other major bioaccumulation studies since 1970. Future monitoring will be guided by assessment questions developed for the SWAMP.  The objective of this report was to evaluate how well the historic data from the State Board programs and from other major monitoring efforts since 1970 address these questions. This exercise has provided a substantial amount of information about present and historical impacts of pollutant bioaccumulation on shing and aquatic life in California, and has also highlighted areas where improved sampling approaches can better address the assessment questions. Present concentrations of pollutants in many California water bodies are high enough to cause concern for possible effects on human health and to have a significant impact on the fishing beneficial use. Consumption advisories, 303(d) listings, and the bioaccumulation database as a whole provide three indices of the status of this impact. Consumption advisories exist for an increasing number of water bodies, but these represent only a fraction of the areas likely to need them. Lack of suitable data is a major impediment to developing advice for additional water bodies. A US E.P.A. evaluation of the 2002 303(d) List indicated that large portions of the state had not been assessed, especially rivers and coastline. Most of the lake area in the state (61%) had been assessed, and a relatively small percentage of the total area (6%) was classified as impaired. Assessment of lakes, however, has focused primarily on the largest lakes, leaving the vast majority of smaller lakes unsampled. Many of these small lakes are near population centers and are popular for shing. Bays and estuaries had been thoroughly assessed (98% of the area) and 93% of the total area was impaired. Evaluation of the most recent monitoring data (collected from 1998-2003) indicates that, for the locations sampled, 32% had low concentrations of pollutants, 42% had moderate concentrations, 18% had high concentrations, and 8% had very high concentrations (Figure 1). Concentrations in the low category are in a range where consumption is generally encouraged by the California Office of Environmental Health Hazard Assessment (OEHHA) (Klasing and Brodberg 2006). OEHHA is the agency responsible for managing health risks due to contaminated sport fish in California. Concentrations in the very high category are in a range where OEHHA discourages consumption (Klasing and Brodberg 2006). Lakes assigned to the moderate, high, or very high concentration categories were primarily affected by mercury, with PCBs also playing a lesser role.

Bulletin No. 38, Report of Kings River Water Master for the Period 1918-1930

California Department of Water Resources (DWR) | December 1st, 1931

*Scan quality is poor on alternate pages. Researchers may want to contact the California Department of Water Resources, or UC Davis, for access to the original.

*Scan quality is poor on alternate pages. Researchers may want to contact the California Department of Water Resources, or UC Davis, for access to the original.

Delta Vision Strategic Plan

State of California | October 17th, 2008

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less th

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less than to create a vision to repair the ecological damage to the Sacramento-San Joaquin River Delta (Delta), and then prepare a strategic plan which would sustain the Delta in future decades while ensuring a reliable water supply for the two-thirds of California’s population who depend in whole or in part on water from the Delta.