Flood Control System Status Report

California Department of Water Resources (DWR) | December 12th, 2011

This Flood Control System Status Report (FCSSR) describes the current status (physical condition) of SPFC facilities at a systemwide level. DWR prepared the FCSSR to meet

This Flood Control System Status Report (FCSSR) describes the current status (physical condition) of SPFC facilities at a systemwide level. DWR prepared the FCSSR to meet the legislative requirements of California Water Code Section 9120, and to contribute to development of the Central Valley Flood Protection Plan (CVFPP). The CVFPP will guide future State investments through projects to address identified problems in the SPFC. The FCSSR is primarily intended to present information on the physical condition of SPFC facilities, and to help guide future inspection, evaluation, reconstruction, and improvement of the facilities. Information contained in the FCSSR should not be used to predict how a levee orassociated facilities may perform in a specific flood event. More detailed information (such as additional geotechnical explorations and analyses at a greater frequency) would be necessary to meet other purposes, such as assessing whether a levee could be certified under Federal Emergency Management Agency (FEMA) standards to provide base flood protection under the National Flood Insurance Program.

Flood-MAR Research and Data Development Plan

California Department of Water Resources (DWR) | October 31st, 2019

The Research Advisory Committee (RAC) is pleased to make this plan available to the growing network of farmers, researchers, planners, and water and land managers who wan

The Research Advisory Committee (RAC) is pleased to make this plan available to the growing network of farmers, researchers, planners, and water and land managers who want to expand our collective knowledge about using floodwaters for managed aquifer recharge (Flood-MAR). This plan outlines the priority information needed by those making management decisions about the where, when, and how of capturing available flood water to replenish California’s depleted aquifers.

Fourth Supplement to State Water Resources Board Bulletin No. 11 San Joaquin County Investigation, Basic Data, Calaveras Unit 1957-58

California Department of Water Resources (DWR) | March 27th, 1959

Fragmented Flows: Water Supply in Los Angeles County

Environmental Management (Springer) | May 12th, 2016

In the Los Angeles metropolitan region, nearly 100 public and private entities are formally involved in the management and distribution of potable water—a legacy rooted

In the Los Angeles metropolitan region, nearly 100 public and private entities are formally involved in the management and distribution of potable water—a legacy rooted in fragmented urban growth in the area and late 19th century convictions about local control of services. Yet, while policy debates focus on new forms of infrastructure, restructured pricing mechanisms, and other technical fixes, the complex institutional architecture of the present system has received little attention. In this paper, we trace the development of this system, describe its interconnections and disjunctures, and demonstrate the invisibility of water infrastructure in LA in multiple ways—through mapping, statistical analysis, and historical texts. Perverse blessings of past water abundance led to a complex, but less than resilient, system with users accustomed to cheap, easily accessible water. We describe the lack of transparency and accountability in the current system, as well as its shortcomings in building needed new infrastructure and instituting new water rate structures. Adapting to increasing water scarcity and likely droughts must include addressing the architecture of water management.

Framing the Problem of Flood Risk and Flood Management in Metropolitan Los Angeles

American Meteorological Society (AMS) | January 1st, 2023

This paper develops the concept of flood problem framing to understand decision-makers’ priorities in flood risk management in the Los Angeles Metropolitan Region in Ca

This paper develops the concept of flood problem framing to understand decision-makers’ priorities in flood risk management in the Los Angeles Metropolitan Region in California (LA Metro). Problem frames shape an individual’s preferences for particular management strategies and their future behaviors. While flooding is a complex, multifaceted problem, with multiple causes and multiple impacts, a decision-maker is most likely to manage only those dimensions of flooding about which they are aware or concerned. To evaluate flood decision-makers’ primary concerns related to flood exposure, vulnerability, and management in the LA Metro, we draw on focus groups with flood control districts, city planners, nonprofit organizations, and other flood-related decision-makers. We identify numerous concerns, including concerns about specific types of floods (e.g., fluvial vs pluvial) and impacts to diverse infrastructure and communities. Our analyses demonstrate that flood concerns aggregate into three problem frames: one concerned with large fluvial floods exacerbated by climate change and their housing, economic, and infrastructure impacts; one concerned with pluvial nuisance flooding, pollution, and historic underinvestment in communities; and one concerned with coastal and fluvial flooding’s ecosystem impacts. While each individual typically articulated concerns that overlapped with only one problem frame, each problem frame was discussed by numerous organization types, suggesting low barriers to cross-organizational coordination in flood planning and response. This paper also advances our understanding of flood risk perception in a region that does not face frequent large floods.

From Climate Traces to Climate Insights: Future Scenarios Analysis for the California Central Valley

California Department of Water Resources (DWR) | October 2nd, 2023

California Water Code Section 10004.6 requires the California Department of Water Resources (DWR) to quantify current and future water conditions in the state. This infor

California Water Code Section 10004.6 requires the California Department of Water Resources (DWR) to quantify current and future water conditions in the state. This information is published in the California Water Plan (Water Plan), which is updated every five years. Water managers and planners constantly face the challenges of planning for an uncertain future where the only constant is change. To address the potential future changes and mitigate the probable risks, water managers must consider and quantify uncertainties and their impacts on water system vulnerability. Although it is not possible to know for certain how population growth, land use decisions, climate, and other factors change over time, water planners must consider these system stressors in long-term planning to evaluate future risks and uncertainty. The Water Plan evaluates many alternative future scenarios as an integral part of its analytical approach to quantify system vulnerability under a range of population and urban growth scenarios, land use, and climate uncertainties.

From crisis to connectivity: Renewed thinking about managing California’s water & food supply

California Roundtable on Water and Food Supply (CRWFS) | April 14th, 2014

Modern water management has largely focused on the near-term objectives of a particular user group, be it agriculture, urban, or environment. Over time, competing demands

Modern water management has largely focused on the near-term objectives of a particular user group, be it agriculture, urban, or environment. Over time, competing demands for our finite water resource has led to intractable water conflicts and a water infrastructure that is managed by a highly complex and fragmented network of local, state, and federal institutions. These institutional and water infrastructures abound with missing, broken, or dysfunctional connections between agricultural, urban, and environmental water users, creating negative impacts for all. Addressing these challenges requires a new and strategic approach that is based in understanding the whole system. Fortunately, a shift toward a whole-systems approach is already developing within a number of disciplines that inform water resource management, food supply systems, and environmental stewardship. In this report, From Crisis to Connectivity: Renewed Thinking about Managing California’s Water and Food Supply, the California Roundtable on Water and Food Supply (CRWFS) builds on this shift and identifies the concepts of connectivity and connected benefits: » Connectivity defines the relationships that link the individual parts of a system to form a whole. It recognizes that the actions of one component within a system have an impact, both on the other components of that same system, and upon other, linked systems. The connectivity approach uses this understanding to better align the interactions between human systems (i.e., engineered resource systems, cultural norms, and institutions) and ecosystems (i.e., climatic, chemical and biological systems, and natural resources). This approach proposes that human systems are a central subsystem of the larger ecosystems, rather than systems that exist apart from and only linked to ecosystems. The goal of this alignment is to more effectively design for, and simultaneously achieve, benefits for agricultural and urban users, while ensuring environmental restoration, protection, and stewardship. » The concept of connected benefits refers to achieving simultaneous benefits across all major water users. The idea of connected benefits builds on the positive historical trend from single to dual and multiple benefits that evolved as a way to respond to California’s increasing water management challenges. Based on our assessment of current needs and the patterns of disconnects, we have identified three initial high-priority areas in which we believe the connectivity approach can effect significant change in California’s food and water systems. Each high-priority area has several principles to help guide assessment of water and food issues, as well as design and implementation of solutions.

From past patterns to future potential: using historical ecology to inform river restoration on an intermittent California river

Landscape Ecology (Springer) | August 30th, 2015

Although human actions have greatly impacted the river’s extent, baseflow hydrology, and riparian habitats, many ecological attributes persist in more limited form, in

Although human actions have greatly impacted the river’s extent, baseflow hydrology, and riparian habitats, many ecological attributes persist in more limited form, in large part facilitated by these fundamental hydrogeological controls. By drawing on a heretofore untapped dataset of spatially explicit and long-term environmental data, these findings improve our understanding of the river’s historical and current conditions and allow the derivation of reach-differentiated restoration and management opportunities that take advantage of local potential.

From the extreme to the mean: Acceleration and tipping points of coastal inundation from sea level rise

American Geophysical Union (AGU) | December 18th, 2014

Relative sea level rise (RSLR) has driven large increases in annual water level exceedances (duration and frequency) above minor (nuisance level) coastal flooding elevat

Relative sea level rise (RSLR) has driven large increases in annual water level exceedances (duration and frequency) above minor (nuisance level) coastal flooding elevation thresholds established by the National Weather Service (NWS) at U.S. tide gauges over the last half-century. For threshold levels below 0.5 m above high tide, the rates of annual exceedances are accelerating along the U.S. East and Gulf Coasts, primarily from evolution of tidal water level distributions to higher elevations impinging on the flood threshold. These accelerations are quantified in terms of the local RSLR rate and tidal range through multiple regression analysis. Along the U.S. West Coast, annual exceedance rates are linearly increasing, complicated by sharp punctuations in RSLR anomalies during El Niño Southern Oscillation (ENSO) phases, and we account for annual exceedance variability along the U.S. West and East Coasts from ENSO forcing. Projections of annual exceedances above local NWS nuisance levels at U.S. tide gauges are estimated by shifting probability estimates of daily maximum water levels over a contemporary 5-year period following probabilistic RSLR projections of Koppet al.(2014) for representative concentration pathways(RCP) 2.6, 4.5, and 8.5. We suggest a tipping point for coastal inundation (30 days/per year with a threshold exceedance) based on the evolution of exceedance probabilities. Under forcing associated with the local-median projections of RSLR, the majority of locations surpass the tipping point over the next several decades regardless of specific RCP.

From the sanitary city to the sustainable city: challenges to institutionalising biogenic (nature’s services) infrastructure

Local Environment (Routledge) | January 4th, 2010

Much has been made of the need for cities to becomemore sustainable, particularly since for the first time in human history over half of the world’s population are urb

Much has been made of the need for cities to becomemore sustainable, particularly since for the first time in human history over half of the world’s population are urban dwellers. Cities concentrate human activities in an exceptionally powerful manner, and this includes resource use and the generation of pollution. Attention has turned towards cities for their capacity to enhance and use nature’s services – ecological sustainability – to remediate some of their own environmental impacts. Insufficient attention has been paid to the challenges of implementation of this new approach to infrastructure in an era of devolution and skepticism about government. This paper discusses these twin and interwoven questions through the lens of an on-going natural experiment, the implementation of a million tree-planting campaign in Los Angeles, CA.