Relationship between wetland size and CRAM condition scores for depressional wetlands

San Francisco Estuary Institute (SFEI) | March 28th, 2016

Report on Salton Sea Projects

California Natural Resources Agency (CNRA) | April 8th, 2016

Formed in 1905 when Colorado River flood waters breached an irrigation diversion structure and caused the river to temporarily flow into the then-dry Salton Sink, today�

Formed in 1905 when Colorado River flood waters breached an irrigation diversion structure and caused the river to temporarily flow into the then-dry Salton Sink, today’s Salton Sea is only the latest in a long succession of waterbodies to occupy the area. At 350 square miles, California’s largest lake is hydrologically connected to the Colorado River system and has been largely maintained since the 1905 event by irrigation water from agricultural production in the Imperial Valley. The historic Quantification Settlement Agreement (2003) provided California the means to implement water transfers and supply programs that allowed the state to live within its 4.4 million acre-foot basic annual apportionment of Colorado River water. Though long plagued by problems associated with its terminality—and resultant accumulation of salts, nutrients, and other impurities—the water transfers contained in the QSA meant a hastening of its ecological decline. Mitigation waters were provided for the Sea in the agreement, but are set to expire in 2017.  In response to growing concern about the impending and current deterioration of conditions at the Salton Sea, California Governor Edmund G. Brown Jr. in May 2015 created the Salton Sea Task Force to rapidly evaluate and take action to bring certainty to the Sea’s future and develop a series of findings that would guide further action at the lake. To coordinate and facilitate the actions the Governor also created the position of Assistant Secretary for Salton Sea Policy within the California Natural Resources Agency (CNRA).  The Salton Sea Task Force issued their findings in November 2015, which called for the development of a Salton Sea Management Program that covered three major elements: sustainable habitat; air quality and potential private sector energy development. The Task Force also acknowledged that a successful program depends on the following three principles: 1) strong state, federal, and local partnerships; 2) clear and achievable milestones with state directed plans to achieve them; and 3) committed participation from all stakeholders who share the goals of protecting air quality, reducing habitat impacts, and maintaining a secure Colorado River Water Supply. Task Force findings also contained a series of actions for implementation by the California Natural Resources Agency (CNRA) that included the development of a Salton Sea Management Plan with short and midterm goals for habitat and dust suppression projects, an improved public awareness and local partnerships program and an accelerated implementation of planning, permitting and construction. 

Residential irrigation as a driver of urban bird communities

Nature Portfolio (Springer Nature) | August 17th, 2009

The demand for fresh water has largely outpaced supply both globally and locally with current water management policies unable to meet the needs of urban, agricultural, a

The demand for fresh water has largely outpaced supply both globally and locally with current water management policies unable to meet the needs of urban, agricultural, and industrial activities. Irrigation is one of the many anthropogenic uses of water and is arguably the most important maintenance factor in a landscape. This is particularly true in an arid climate, such as the Central Valley of California. Urban residents' decisions about the design and maintenance of their landscapes affect bird species richness. Published research indicates that these decisions are also affected by the residents' socioeconomic status. However, the driver of this relationship remains unknown. This paper uses data from the Fresno Bird Count, a citizen science organization, to test the hypothesis that neighborhood socioeconomic status influences residential irrigation regimes, which influences plant cover, in turn influencing bird diversity and abundance. A random sampling grid containing 460 points are used as locations for five minute point counts for the Fresno Bird Count ("fresnobirds.org":http://fresnobirds.org/). Socioeconomic data has been obtained from the U.S. Census and irrigation regimes from the city of Fresno. Aerial imagery and ground sampling on point count locations are used for characterizing habitat. Preliminary analysis of the first year of data (2008) supports this hypothesis and reveals a north/south gradient of bird diversity paralleling the socioeconomic gradient of Fresno. This paper will present results from a more comprehensive analysis of data including the spring 2009 bird census. Policies in the U.S. regarding the distribution and cost of water are changing in response to increased water demands, and the city of Fresno is about to undergo such a change. In 2013 a policy of metered water is scheduled to begin, which is predicted to increase water conservation by residents due to an increase in it overall cost. In addition to examining coupled socio-ecological drivers of urban diversity, this study will be the first part of a Before After Control Impact experiment taking advantage of the planned implementation of metering the cost of water use. The results can help guide the city in improving its management of urban habitat and biodiversity.

Response in the water quality of the Salton Sea, California, to changes in phosphorus loading: an empirical modeling approach

Hydrobiologia (Springer) | January 10th, 2008

Salton Sea, California, like many other lakes, has become eutrophic because of excessive nutrient loading, primarily phosphorus (P). A Total Maximum Daily Load (TMDL)

Salton Sea, California, like many other lakes, has become eutrophic because of excessive nutrient loading, primarily phosphorus (P). A Total Maximum Daily Load (TMDL) is being prepared for P to reduce the input of P to the Sea. In order to better understand how P-load reductions should affect the average annual water quality of this terminal saline lake, three different eutrophication programs (BATHTUB, WiLMS, and the Seepage Lake Model) were applied. After verifying that specific empirical models within these programs were applicable to this saline lake, each model was calibrated using water quality and nutrient-loading data for 1999 and then used to simulate the effects of specific P-load reductions. Model simulations indicate that a 50% decrease in external P loading would decrease near-surface total phosphorus concentrations (TP) by 25– 50%. Application of other empirical models demonstrated that this decrease in loading should decrease near-surface chlorophyll a concentrations (Chl a) by 17–63% and increase Secchi depths (SD) by 38–97%. The wide range in estimated responses in Chl a and SD were primarily caused by uncertainty in how non-algal turbidity would respond to P-load reductions. If only the models most applicable to the Salton Sea are considered, a 70–90% P-load reduction is required for the Sea to be classified as moderately eutrophic (trophic state index of 55). These models simulate steady-state conditions in the Sea; therefore, it is difficult to ascertain how long it would take for the simulated changes to occur after load reductions.

Responsible Exports Plan

Environmental Water Caucus | May 29th, 2013

The consensus diagnosis for the Delta estuary is dire. The California Environmental Water Caucus prescribes more river flows and reduced fresh water exports to help the D

The consensus diagnosis for the Delta estuary is dire. The California Environmental Water Caucus prescribes more river flows and reduced fresh water exports to help the Delta recover. The EWC’s plan demonstrates how water supply reliability can be improved while reducing exports from the Bay Delta Estuary. Many of our recommendations have been presented to the Delta Stewardship Council as part of Alternative 2 for the Delta Plan. We have now packaged this series of related actions into a single alternative for evaluation in any future NEPA or CEQA evaluations, or by the State Water Resources Control Board. The actions are largely based on the EWC report California Water Solutions Now, (www.ewccalifornia.org), which can be referenced for supporting details. This package of actions (“The RX Plan”) represents the EWC alternative to the BDCP. The RX Plan includes a unique combination of actions that will open the discussion for alternatives to the currently failed policies which continuously attempt to use water as though it were a limitless resource. The RX Plan is about far more than just reduced exports. The uniqueness of this Plan is that while it will reduce the quantity of water exported from the Bay Delta Estuary, in order to protect the health of the Estuary’s habitat and fisheries with increased inflows and outflows, it also contains actions that will reduce the demand for water and increase supplies for exporters south of the Delta in order to compensate for the reduced south-of-Delta exports. It is the only extant plan that will modernize existing facilities in the Bay-Delta with improved fish screens at the South Delta, levees reinforced above the PL84-99 standard, and significantly increased flows in order to recover habitat and fish stocks, while avoiding the huge infrastructure costs of tunnels under the Delta. It will also provide increased self-reliance for south-of-Delta water users through inter-regional water transfers and south of Delta groundwater storage. The reinforced levees will provide increased reliability of the water supplies through the Delta. And it will accomplish the legislated goals of Estuary restoration and water reliability for billions of dollars less than currently contemplated plans.

Restoration pulse flows from a California dam temporarily increase drifting invertebrate biomass concentration

Journal of Environmental Management (Elsevier) | November 9th, 2022

The decline of Pacific salmon (Oncorhynchus spp.) populations over the last few decades has stimulated major restoration efforts across the Pacific Northwest to improve t

The decline of Pacific salmon (Oncorhynchus spp.) populations over the last few decades has stimulated major restoration efforts across the Pacific Northwest to improve the status of these iconic fishes. The leading factors contributing to the decline of Pacific salmon include watershed degradation and water diversions, which result in part from widespread dam construction across the United States (Moyle, 1994). Early river restoration actions primarily focused on physical habitat alterations (e.g., in-stream habitat improvement, fish passage; Barinaga, 1996; Bernhardt et al., 2005), while more recent work has centered around restoring natural processes (Johnson et al., 2019). Since socioeconomic and political complications are typically too great for dam removal projects to be feasible, reconciliation ecology, which encourages the accommodation of both human and wildlife needs in a human-dominated landscape, can be a more effective approach to restoration (Rosenzweig, 2003; Moyle et al., 2017). Rather than the elusive goal of returning rivers to a natural flow regime, the aim can be to attain functional environmental flows to support beneficial flow-ecology relationships (Poff et al., 2017). Dams can be operated to reduce some of their detrimental effects by releasing flows that improve downstream habitat through the preservation of key hydrologic signals upon which biophysical processes and native biological communities depend (Yarnell et al., 2020). Four functional flow components were identified for Mediterranean montane streams: wet-season initiation flows, peak magnitude flows, spring recession flows, and dry-season low flows; see Yarnell et al. (2015) for a description about the importance of each key functional component. Several studies have identified the need to further assess linkages between streamflow, invertebrate prey availability, and drift-foraging dynamics for consideration in future restoration plans for juvenile salmonids (Weber et al., 2014; Naman et al., 2016; Lusardi et al., 2018). The focus of this study is to assess the impact of dam-release flows imitating one of those functional flow components, peak magnitude flows, on invertebrate drift as a food resource for juvenile salmonids.

Restoring Habitat with Science and Society in Mind

Delta Stewardship Council (Delta Council) | April 8th, 2014

This Issue Paper, authored by Jessica Davenport, the Council's Program Manager for Ecosystem Restoration and Land Use, is entitled Restoring Habitat with Science and Soci

This Issue Paper, authored by Jessica Davenport, the Council's Program Manager for Ecosystem Restoration and Land Use, is entitled Restoring Habitat with Science and Society in Mind.  The purpose of the 22-page paper is to survey restoration activities in the Delta; describe the needs, progress and opportunities related to restoration; and propose key areas of focus for the Delta Stewardship Council and other agencies to advance habitat restoration. Some of the areas of focus for Council staff for the next two years include: Continue to provide early consultation on habitat restoration projects that are Covered Actions under the Delta Plan in order to advise project proponents on using best available science and adaptive management and avoiding or reducing conflicts with existing uses, where feasible. Report on habitat performance measures by December 2014 and again in December 2015. Work with others to complete at least one of the landscape-scale conceptual models and associated landscape habitat metrics for the priority habitat restoration areas. Enagage Delta Plan Interagency Implementation Committee members in discussions of challenges and potential solutions related to land acquistion and permit coordination.

Reversal in estuarine sand supply driven by Holocene sea level rise: A model for sand transport in large structural estuaries, San Francisco Bay, California, USA

Elsevier | July 26th, 2024

Coastal sand supply is a critical component of shoreline stability in the face of modern threats to coastal zones such as sea level rise or anthropogenic sediment extract

Coastal sand supply is a critical component of shoreline stability in the face of modern threats to coastal zones such as sea level rise or anthropogenic sediment extraction. Understanding the natural and anthropogenically perturbed dynamics of coastal systems has become a pressing challenge for coastal communities, such as the San Francisco Bay area in the United Sates, a large structurally controlled estuary system where stakeholders seek to balance the extraction of coastal sand resources for economic use and ensure sufficient sand supply for sustaining natural coastal environments. Developing accurate and comprehensive models of sand inputs and transport pathways in different types of coastal systems is imperative to balancing these competing needs. While estuarine sediment transport has been well-studied in many systems globally, structurally controlled estuaries in tectonically active settings have received relatively less attention. The prevailing hypothesis for sediment transport through San Francisco Bay describes active input and transport of sand from a large integrated regional catchment, through multiple subembayments, and out to Pacific coast beaches; a model contrary to prevailing understanding of highstand estuarine sediment transport in most settings. We test this model by applying comprehensive sand provenance analysis to surface and near-surface sand deposits in and around San Francisco Bay coupled with sand residence time data from optically stimulated luminescence (OSL) dating. New provenance results include sand petrography modal abundances, bulk geochemistry, and U-Pb detrital zircon geochronology from 27 Holocene samples throughout the San Francisco Bay region. Collectively, these new results highlight marked sediment provenance and residence time differences between San Francisco Bay structural subembayments. In particular, distinct compositional differences and OSL ages exist between sand in the bayhead region of the estuary (OSL ages ca. 4 ka; Sacramento River/local provenance) and sand from the more distal bay regions and the Pacific coast (OSL ages ca. 1 ka; integrated Sierra Nevada provenance). These provenance differences better support a revised sand input and transport model with disconnected depocenters across three structurally restricted subembayments from bayhead to the Pacific coast. New data suggest that at present the bayhead region receives limited supply from the Sacramento-San Joaquin Delta drainage with subsidiary supply from local circum-bay drainages. Sand deposited in the region from the Pacific coast through the inlet (Golden Gate) and into the estuary consists of a combination of tidal winnowing and reworking of “relic” sand from lowstand periods combined with sand eroded from Pacific coast sea cliffs, and sand supply from local Coast Range drainages. These results suggest that sand is likely not transported directly to the Pacific coast from the Sacramento-San Joaquin Delta under modern conditions. Moreover, it is likely that structural constrictions between the main estuary and outer coast and between estuary subembayments cause abrupt cessation of sediment input from the main regional drainage during marine flooding, a feature likely common to large structurally controlled estuaries globally. This revised model for San Francisco Bay sand transport illustrates the need for research targeted at interpreting natural sand transport pathways in coastal systems where coarse sediment supply is a sustainability concern.

Review of 2018 Ocean Salmon Fisheries Stock Assessment and Fishery Evaluation Document for the Pacific Coast Salmon Fishery Management Plan

Pacific Fishery Management Council | February 11th, 2019

Review of CDFW Recommendations for the 2022 Readoption of Drought Emergency Regulations on the Scott River and Recommendations for Future Management During Extreme Drought Conditions

Siskiyou Farm Bureau | August 31st, 2022