Case Studies of Natural Shoreline Infrastructure in Coastal California: A Component of Identification of Natural Infrastructure Options for Adapting to Sea Level Rise

Nature Conservancy | November 27th, 2017

Sea level rise and erosion are major threats to California’s coast, requiring solutions to preserve the many benefits a healthy coastline provides: flood protec

Sea level rise and erosion are major threats to California’s coast, requiring solutions to preserve the many benefits a healthy coastline provides: flood protection, recreation, habitat for wildlife, water quality and more. Seawalls and other engineered structures, are commonly installed in order to hold the shoreline in place and hold back the ocean; however, they ultimately make the situation worse in most cases by increasing erosion and thus causing already vulnerable shorelines to shrink more. Natural shoreline infrastructure is an alternative that is more likely to preserve the benefits of coastal ecosystems while also maintaining coastal access. The California coastline is very diverse, and no single solution will address all the chal- lenges anticipated in the future. While there is a continuum of approaches to address sea level rise and coastal erosion— ranging from fully natural approaches that preserve or restore natural systems, hybrid solutions that integrate engineered aspects into restored or created natural features, and fully engineered structures like seawalls and revetments—prop- erty owners and managers don’t typically consider the entire range of options when making coastal management decisions. To address the gap in familiarity with natural infrastructure and the lack of technical guidance to aid decision-makers and engineers in the appropriate application of different strategies for different situations, this report summarizes natural infrastructure projects for a range of settings in coastal California. Each case study covers the background, permitting, planning, implementation, performance, and key lessons learned from each project in order to provide the critical information needed to implement successful adaptation strategies to address coastal issues, and inspire other communities by highlighting the lessons learned.

CASGEM Alternative Monitoring Plan Fact Sheet

California Department of Water Resources (DWR) | August 15th, 2023

Castac Lake Valley Groundwater Sustainability Plan

Castac Basin Groundwater Sustainability Agency | September 17th, 2020

The Castac Lake Valley Groundwater Basin (also referred to herein as “the Basin”), California Department of Water Resources (DWR) Basin No. 5-029, is located at the

The Castac Lake Valley Groundwater Basin (also referred to herein as “the Basin”), California Department of Water Resources (DWR) Basin No. 5-029, is located at the southern end of Kern County. The Basin is identified by DWR as being a very low priority basin, and as such, this GSP and associated SGMA compliance efforts have been conducted on a voluntary basis. Due to size, the file has been divided into two parts. Part 1, Part 2

Causes of accelerated High-Tide Flooding in the U.S. since 1950

Nature Portfolio (Springer Nature) | December 15th, 2023

Causes of extreme ridges that induce California droughts

American Meteorological Society (AMS) | February 15th, 2017

California droughts are often caused by high-amplitude and persistent ridges near and off the west coast of North America without apparent connections with ENSO. Here wi

California droughts are often caused by high-amplitude and persistent ridges near and off the west coast of North America without apparent connections with ENSO. Here with a hierarchy of climate models, it is demonstrated that extreme ridges in this region are associated with a continuum of zonal wavenumber-5 circumglobal teleconnection patterns that originate from midlatitude atmospheric internal dynamics. Although tropical diabatic heating anomalies are not essential to the formation and maintenance of these wave patterns, certain persistent heating anomalies may double the probability of ridges with amplitudes in the 90th percentile occurring on interannual time scales. Those heating anomalies can be caused by either natural variability or possibly by climate change, and they do not necessarily depend on ENSO. The extreme ridges that occurred during the 2013/14 and 2014/15 winters could be examples of ridges produced by heating anomalies that are not associated with ENSO. This mechanism could provide a source of subseasonal-tointerannual predictability beyond the predictability provided by ENSO.

Causes of the 2011‐14 California Drought

American Meteorological Society (AMS) | September 15th, 2015

The causes of the California drought during November–April winters of 2011/12–2013/14 are analyzed using observations and ensemble simulations with seven atmo

The causes of the California drought during November–April winters of 2011/12–2013/14 are analyzed using observations and ensemble simulations with seven atmosphere models forced by observed SSTs. Historically, dry California winters are most commonly associated with a ridge off the west coast but no obvious SST forcing. Wet winters are most commonly associated with a trough off the west coast and an El Niño event. These attributes of dry and wet winters are captured by many of the seven models. According to the models, SST forcing can explain up to a third of California winter precipitation variance. SST forcing was key to sustaining a high pressure ridge over the west coast and suppressing precipitation during the three winters. In 2011/12 this was a response to a La Niña event, whereas in 2012/13 and 2013/14 it appears related to a warm west–cool east tropical Pacific SST pattern. All models contain a mode of variability linking such tropical Pacific SST anomalies to a wave train with a ridge off the North American west coast. This mode explains less variance than ENSO and Pacific decadal variability, and its importance in 2012/13 and 2013/14 was unusual. The models from phase 5 of CMIP (CMIP5) project rising greenhouse gases to cause changes in California all-winter precipitation that are very small compared to recent drought anomalies. However, a long-term warming trend likely contributed to surface moisture deficits during the drought. As such, the precipitation deficit during the drought was dominated by natural variability, a conclusion framed by discussion of differences between observed and modeled tropical SST trends.

Causes of the Extreme Dry Conditions over California During Early 2013

American Meteorological Society (AMS) | September 30th, 2014

The state of California experienced extreme dry conditions during early 2013. In particular, January and February received 28% and 15%, respectively, of their nor

The state of California experienced extreme dry conditions during early 2013. In particular, January and February received 28% and 15%, respectively, of their normal monthly rainfall. When January and February are combined, January/ February 2013 is ranked as the driest of the period 1895–2014. Such large precipitation deficits exerted enormous stress on water resources in an already high water-demand region. Thus, it is of practical importance to investigate the causes of this extreme climate event so as to assess its predictability. *Chapter 3, Explaining Extreme Events of 2013 from a Climate Perspective, Bull. Amer. Meteor. Soc., 95 (9)

Causes of Variability in Suspended‐Sand Concentration Evaluated Using Measurements in the Colorado River in Grand Canyon

American Geophysical Union (AGU) | July 29th, 2020

Rivers commonly exhibit substantial variability in suspended‐sand concentration, even at constant water discharge. Here we derive an approach for evaluating how m

Rivers commonly exhibit substantial variability in suspended‐sand concentration, even at constant water discharge. Here we derive an approach for evaluating how much of this variability arises from mean bed‐sand grain size. We apply this approach to the Colorado River in Grand Canyon, where discharge‐independent concentration of suspended sand varies by more than a factor of 23 (N = 1.4 × 106). Theory predicts that where concentration is controlled by bed‐sand grain size, concentration and grain size in suspension will be inversely correlated (i.e., coarsening of the bed causes suspended sand to become coarser in grain size and lower in concentration). Although the observed correlation is negative, riverbed grain size accounts for only 40% of the variability in concentration. The residuals vary by an order of magnitude; they arise from other processes, such as changes in topography or distribution of sand that cause shear stress to change at constant discharge, changes in the fine tail of bed‐sand grain sizes or changing bedforms. Both bed sand and the other factors influence concentration for durations from less than 1 day to several years. Predictions of concentration based on bed‐sand grain size (N = 4 × 104) are less accurate than predictions based on suspended‐sand grain size, probably because suspended sand is a natural integrator of sand‐transporting processes, giving more weight to those areas of the bed that exchange more sand with the flow. Although the causes of variability vary from one river to another, the approach illustrated here is applicable to any river in which concentration varies at constant water discharge.

CE2 Model: Evaluating the Costs and Benefits of Urban Water Conservation and Efficiency Measures

Pacific Institute | April 26th, 2012

Over the past 25 years, water conservation and efficiency improvements have provided real water savings, allowing many agencies to maintain or reduce water use while meet

Over the past 25 years, water conservation and efficiency improvements have provided real water savings, allowing many agencies to maintain or reduce water use while meeting the needs of a growing population and economy. Recent studies indicate that despite the improvements that have already been achieved, significant water conservation potential remains. Indeed, California legislation passed in 2009 requires urban water agencies to reduce per capita water use by 20% by the year 2020. The economics of water conservation and efficiency are key issues. The Pacific Institute has developed the Cost Effectiveness of Water Conservation and Efficiency (CE2) Model to help evaluate the economic desirability of water conservation and efficiency measures and explore how costs and benefits can be shared among customers, water utilities, and other entities (system requirements: PC with Microsoft Excel and Access 2003* or later). The model helps document the costs of starting and running a conservation program and estimate the associated water, energy, and financial savings. It is sufficiently general and flexible to address variations in conservation measures regionally and according to the level of analysis because the model outputs are based on conditions defined by the user. The CE2 Model does not provide “the answer” as to whether a particular measure or suite of measures makes economic sense. Rather, it provides a set of financial metrics that can inform the decision-making process. The CE2 Model can also help water conservation practitioners share information across departments and with other water, wastewater, and energy utilities. The model quickly and easily calculates financial metrics that are meaningful and readily understood by planners and managers. It also provides a common platform through which to discuss the costs and benefits of water conservation and efficiency. This in turn allows utilities to exchange cost experiences and data and learn from one another more easily. The primary audience for the CE2 Model is water utility staff. The model is appropriate for wholesale and retail utilities of all sizes and can be used by agencies that exclusively provide water services, as well as agencies that also provide wastewater and/or energy services. Additionally, it may be of use to consultants, non-governmental organizations, and others interested in water conservation and efficiency and sustainable management of water resources.

Center for Biological Diversity vs. Lincoln County Water District

Nevada Appellate Courts | January 25th, 2024

This case examines whether the State Engineer has the authority to redesignate multiple existing hydrographic basins as one "superbasin" based on a shared source of water

This case examines whether the State Engineer has the authority to redesignate multiple existing hydrographic basins as one "superbasin" based on a shared source of water for purposes of the water's administration and management. We also look at whether the State Engineer complied with due process in creating the superbasin at issue here.