California is one of the most hydrologically altered landscapes in the world. As water becomes ever more scarce and the human population continues to grow, that vast engineered system strains to meet the needs of people let alone the needs of nature.
Water rights allocations far exceed actual surface water supply, and millions of wells tap groundwater to meet the increasing demands of farms and communities. As groundwater reservoirs are depleted they can in turn reduce surface flows – exacerbating a vicious cycle in which people and nature both lose. Rivers, wetlands and groundwater-dependent ecosystems are caught in this struggle for an increasingly limited resource. Nearly half of California’s roughly 4,000 freshwater species are considered vulnerable to extinction. Of the taxa that are found nowhere but California – our endemic freshwater biodiversity – 90 percent are at risk.
But there is hope. While it is impossible to return natural flows to most of California’s rivers and streams, we can – through science, technology, and innovative market tools – endeavor to deliver water when and where nature needs it most.
In a normal year, groundwater accounts for 40 percent of California’s water supply. That number jumps to 60… >>
Californians have fundamentally altered many of the state’s rivers and streams with dams, pipes, and diversions, and the… >>
Adam H. Love, Andy Zdon, Naomi S. Fraga, Brian Cohen, Maura Palacios Mejia, Rachel Maxwell, Sophie Parker
This paper presents results from the Mojave Desert Springs research project. The authors present a comprehensive statistical analysis of similarities between California desert springs. An observed lack of correlation between the springs’ hydrologic and ecological parameters suggests that each spring represents a somewhat unique…
Suman Jumani, Lucy Andrews, Theodore E. Grantham, S. Kyle McKay, Jeffrey Duda, Jeanette Howard
California has a dam problem. Since the start of the 20th century, the state has built thousands of dams on its rivers and streams. Now, more than 75% of the largest dams are greater than 50 years old. This means that a significant proportion of…
Kristen Wilson, Dale W. Johnson, Douglas F. Ryan, ed.
Authored by TNC staff and colleague, Chapter 8 of this report synthesizes environmental monitoring and studies performed at Sagehen Experimental Forest that are relevant to water quality regulatory agencies. Water quality in the basin is mainly controlled by groundwater emerging in springs, but wildland fires,…
James W. Roche, Kristen N. Wilson, Qin Ma, Roger C. Bales
This study evaluated the water balance components of precipitation, evapotranspiration, discharge, and change in storage compared to measured streamflow and unregulated streamflow estimates in the central Sierra Nevada. The fifty-two watersheds varied in size and in elevation. This study found that the evapotranspiration estimates plus gridded…
Mark G. Anderson, Melissa Clark, Arlene P. Olivero, and D. Richard Cameron
In response to biodiversity loss, scientists have called for the protection of well-connected systems of protected areas covering 30 to 50% of the planet. However, as climate change drives shifts in species, conservation plans based on current biodiversity patterns will become less effective. The authors…
Kristina Kreter, Shona Ganguly, Rowan Roderick-Jones, and Kelsey Jessup
New strategies to address urban runoff management with nature-based approaches offer promising solutions to alleviating climate change impacts—like urban heat, water shortages, and floods—and environmental pollution and the loss of natural green space that diminish the quality of life for vulnerable communities. Vegetated…
Julie Zimmerman, Jennifer Carah, Kirk Klausmeyer, Gabe Rossi, Mia Van Docto, Jeanette Howard, Charlie Schneider, Matt Clifford, Monty Schmitt
Drought conditions are occurring with more frequency, greater severity, and longer duration under climate change. Human water use compounds the effects of drought, further stressing California’s ecosystems, impacting farms, rural communities and urban water supplies. The Salmon and Steelhead Coalition developed a Drought Flows Monitor…
The Nature Conservancy, radbridge, Earth Economics
FEMA increasingly recognizes and emphasizes the role of nature-based solutions (NBS) for building community resilience to hazards like flood, wildfire, and drought, and the agency has made remarkable progress on policies and resources to support NBS in a relatively short period. However, anecdotally it remains…
Taylor-Burns, R., Heard, S., Beck, M. W.
There is growing evidence for the beneficial role that wetlands can play in reducing flood risk, but in many urban estuaries, coastal development has resulted in dramatic habitat loss and fragmentation. In the past several decades, marsh restoration has emerged as a core management objective…
Scott Morrison, Brynn Pewtherer
The Nature Conservancy deploys science to help overcome major challenges facing people and nature. In today’s fast-paced world, turning threats to nature into opportunities for conservation requires agility. The Conservation Science Catalyst Fund enables our science team to mobilize quickly — and produce the information…
Naomi S. Fraga, Brian S. Cohen, Andy Zdon, Maura Palacios Mejia, Sophie S. Parker
This paper presents novel botanical inventories of 48 desert springs as part of the Mojave Springs Research Project. The authors assess plant species composition and richness within and between springs and evaluate how botanical diversity relates to physical and hydrological parameters. The results of…
The Nature Conservancy, FEMA, Nonlinear Ventures, radbridge, Earth Economics
To address the increasing risk of catastrophic flooding, wildfire and other climate-related threats, communities are pursuing nature-based solutions (NBS) and seeking FEMA hazard mitigation funds to support this work. Of all the required activities, the Environmental & Historic Preservation (EHP) review is often cited as…
Sophie S. Parker, Linnea S. Hall, Mary J. Whitfield, Laura Riege, Kathryn R. Selm, René Corado
This paper presents results from a field-based study that can be used to benefit songbirds in riverside habitats like those found along the Santa Clara River in Ventura County, California. Songbirds such as the Least Bell’s Vireo suffer population declines in part because Brown-headed…
UC Santa Cruz (Austen E. Stovall, Michael W. Beck), The Nature Conservancy (Alyssa Mann, Tamaki Bieri), Radbridge/formerly Earth Economics (Johnny Mojica, Rowan Schmidt)
Climate change poses severe threats to coastal communities and the ecosystems on which they depend. Warming ocean temperatures increase the magnitude and frequency of storm and coral bleaching events, allowing less time for recovery amidst these threats. Coral reefs complex and stable structure protects against…
Eric D. Stein, Michael E. McClain, Ashmita Sengupta, Theodore E. Grantham, Julie K.H. Zimmerman, Sarah M. Yarnell
In this chapter of Water Resources Allocation and Agriculture, the authors provide insights on how to integrate environmental flows into water allocation for agriculture across the world. They argue that holistic environmental flows approaches that are fully protective of ecosystem needs and integrate surface and…
The Nature Conservancy, Earth Economics
FEMA requires that hazard mitigation projects must be cost-effective to the federal government, as demonstrated in a Benefit-Cost Analysis (BCA), which compares the present value of a project’s future benefits and costs. A BCA is required for the vast majority of FEMA-funded hazard mitigation projects,…
Sophie S. Parker, Bradley Franklin, Brian S. Cohen, Melissa M. Rohde, Michael Clifford, Andrew Williams
Climate change will cause severe financial, social, and environmental upheaval if a massive reduction in carbon emissions is not achieved by 2030. To address this challenge, rechargeable lithium-ion batteries will play a key role in transitioning the energy and transportation sectors away from fossil fuel…
Heather Tallis, Joe Fargione, Edward Game, Rob McDonald, Leandro Baumgarten, Nirmal Bhagabati, Rane Cortez, Bronson Griscom, Jonathan Higgins, Christina M. Kennedy, Joe Kiesecker, Timm Kroeger, Trina Leberer, Jennifer McGowan, Lisa Mandle, Yuta J. Masuda, Scott Morrison, Sally Palmer, Rebecca Shirer, Priya Shyamsundar, Nicholas H.Wolff, and Hugh P. Possingham
Spatial analysis is a powerful tool in conservation planning. Yet it is often under-deployed as a means of elucidating which conservation actions may deliver the highest return on investment. This paper presents a framework for “spatial action mapping” and discusses how it can improve conservation…
Christopher J. Lortie, Maria Florencia Miguel, Alessandro Filazzola, Harry Scott Butterfield
Climate change, drought, and water scarcity are driving major land transformations in dryland ecosystems globally. Historically these ecosystems have been disproportionately degraded due to widespread agricultural conversion. Because of these pressures, there are significant opportunities for rewilding and restoration of these dryland ecosystems. This global…
