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2017 Flood System Status Report
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2017 Flood System Status Report
Department of Water Resources | August 10, 2017...
Summary
This report is intended to assist flood management planners and engineers in characterizing facilities within the State Plan of Flood Control (SPFC) and...
This report is intended to assist flood management planners and engineers in characterizing facilities within the State Plan of Flood Control (SPFC) and to inform the 2017 Central Valley Flood Protection Plan Update (2017 CVFPP Update). The 2017 FSSR provides a concise repository of the status of SPFC Facilities as noted in related DWR evaluation and inspection efforts, along with the efforts of our local and federal partners. The 2012 CVFPP laid the foundation necessary for compliance with the Central Valley Flood Protection Act of 2008 and a new approach to flood management in the Central Valley.

As a supporting and informational document to the 2017 CVFPP Update, the 2017 FSSR includes information about inspecting and evaluating SPFC facilities. It also details and quantifies major components of existing flood risk within the Sacramento and San Joaquin river watersheds, and the factors that influence flood risk in relation to the various flood control structures within the SPFC. Additionally, the 2017 FSSR informs and details the current conditions of levees and channels within the SPFC, and includes finalized project information from DWR’s Levee Evaluations Program. Through updating the status of SPFC facilities, the State of California can continue to make informed decisions related to flood risk management.

This document is a collaborative effort by DWR, local, and federal partners, signifying a step forward in gaining deeper understanding of the flood system’s current status and condition in the Central Valley.

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A Water Resources Data-Network Evaluation for Monterey County, California, Phase 3: Northern Salinas River Drainage Basin
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A Water Resources Data-Network Evaluation for Monterey County, California, Phase 3: Northern Salinas River Drainage Basin
U.S. Geological Survey, Monterey County Flood Control and Water Conservation District | December 15, 1990...
Summary
This report presents an evaluation of water resources data collection networks in the northern Salinas River drainage basin, Monterey County, California. The evaluation,...

This report presents an evaluation of water resources data collection networks in the northern Salinas River drainage basin, Monterey County, California. The evaluation, done in cooperation with the Monterey County Flood Control and Water Conservation District, covers both quantity and quality monitoring by precipitation, surface-water, and ground-water networks. The report describes existing networks in the study area and possible additional data collection.

The study identified 34 precipitation gages in the study area, of which 20 are active. The stations are concentrated in the northwestern part of the study area. Data are lacking for the eastern and southern parts of the study area, as well as the southwestern slopes of the Gabilan Range. No precipitation-quality networks were identified. Possible data-collection efforts for precipitation quality include monitoring for acid rain and for pesticides in precipitation.

The study identified 10 streamflow-gaging stations, of which 6 are active. To meet the objectives for streamflow networks that are outlined in the report, all sites could be reactivated, and two of the inactive sites could be relocated to improve the reliability of the data. Besides these stations, nine possible additional streamflow-gaging sites were identified.

The Monterey County Flood Control and Water Conservation District samples one surface-water site for suspended sediment, specific conductance, and chlorides. Several agencies have done water-quality sampling in the past, but only five sites are active. Reactivation of the 45 inactive sites might help to meet the various surface-water-quality objectives described in the report. Development of a stream-reach rating system also could help to identify parts of the study area most in need of sampling.

The Monterey County Flood Control and Water Conservation District maintains three networks to measure ground-water levels on a monthly basis, during peak irrigation, and at the end of the irrigation season. The District measures water levels in 318 wells. The only other network identified for this report was operated by the U.S. Geological Survey, and none of its five wells are active. The study identified 128 sections in which no ground-water-level monitoring is presently done. Well coverage is densest in the saltwater-intrusion areas near Castroville, California. Wells in the rest of the study area are more sparsely distributed and are concentrated down the center of the drainage basin in the alluvial ground-water basin.

The ideal initial baseline network of ground-water-quality wells would be an evenly spaced grid of index wells within each aquifer, with a density of one per section. Once baseline conditions were established, representative wells could be selected and monitored annually. As of 1985, the Monterey County Flood Control and Water Conservation District monitored 379 study wells in the area for various water-quality conditions. Other networks monitor (or propose the monitoring of) 135 wells. The District collects samples in summer months to monitor saltwater intrusion near Castroville.

Annual samples also are analyzed for chloride, specific conductance, and nitrate. Every 5 years, the District does a complete mineral analysis on each study well. Improvements in network coverage are suggested to better approximate ideal network coverage. The adequacy of wells in existing monitoring networks for representing actual conditions in the ground-water basins was not established conclusively.

Possible redundancy of information from existing networks was not evaluated statistically. Despite these limitations, this report does provide a basis for assessing the adequacy of ground-water-level networks in the study area. The computerized Geographic Information System (GIS) that is planned for Monterey County could easily use the information in this report for the needed initial analysis of network adequacy. The feasibility of management and analysis of large complicated data bases (such as the ground water networks identified in this report) is substantially improved through the use of state-of-the-art GIS tools now available.

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California’s Flood Future: Recommendations for Managing the State’s Flood Risk
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California’s Flood Future: Recommendations for Managing the State’s Flood Risk
Department of Water Resources | November 1, 2013...
Summary
California is at risk for catastrophic flooding that could have wide-ranging impacts due to the size of its economy and the number of...
California is at risk for catastrophic flooding that could have wide-ranging impacts due to the size of its economy and the number of people residing in the state. The State’s economy ranks ninth globally; therefore, the consequences associated with its potential exposure to property damage, economic harm, and loss of life are great.

California is the nation’s most populous state, ranks third largest in land size, and has widely varying climates and topographies, all of which make developing one-size-fits-all solutions to flood risk management impracticable.

In California, 20 percent of the almost 38 million residents live within 500-year floodplains (i.e., have a 0.2 percent chance of flooding in a given year). Four of the nation’s 15 largest cities are in California (Los Angeles, San Diego, San Jose, and San Francisco), and all are at risk for some type of flooding. These factors make decisions regarding California’s flood risk management policies and financial investments vital to the State and the nation.

This report, California’s Flood Future: Recommendations for Managing the State’s Flood Risk (Flood Future Report) presents an overview of the flood threats facing the state, approaches for reducing flood risk, and recommendations for managing California’s flood risk. The Flood Future Report is the first statewide report to be developed through collaboration between the California Department of Water Resources (DWR) and the United States Army Corps of Engineers (USACE). As a joint report by the State and Federal governments, the document represents an unprecedented level of intergovernmental cooperation, including tribal entities.1 Additionally, this report would not have been possible without the participation of and information shared by more than 140 local flood management agencies.

The Flood Future Report represents the first characterization of flood management activities and exposure to flood hazard throughout each county and hydrologic region of the state. This statewide assessment is intended to provide valuable information for local, State, and Federal decision makers as they chart California’s complex flood management future.

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California’s Water: Preparing for Floods
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California’s Water: Preparing for Floods
Public Policy Institute of California | October 1, 2016...
Summary
One in five residents and billions of dollars in assets are vulnerable to flooding. Climate change brings new vulnerabilities. This brief describes new...

One in five residents and billions of dollars in assets are vulnerable to flooding. Climate change brings new vulnerabilities. This brief describes new tools and approaches that can reduce these risks.

This publication is part of a briefing kit that summarizes a dozen of the state’s most pressing water management issues.

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Central Valley Flood Protection Plan (2012)
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Central Valley Flood Protection Plan (2012)
Department of Water Resources | June 12, 2012...
Summary
The Central Valley Flood Protection Plan (CVFPP) is a critical document to guide California’s participation (and influence federal and local participation) in managing...
The Central Valley Flood Protection Plan (CVFPP) is a critical document to guide California’s participation (and influence federal and local participation) in managing flood risk along the Sacramento River and San Joaquin River systems. The CVFPP proposes a system-wide investment approach for sustainable, integrated flood management in areas currently protected by facilities of the State Plan of Flood Control (SPFC).

The CVFPP will be updated every five years, with each update providing support for subsequent policy, program, and project implementation.

The State of California (State) conducted planning and investigations for the 2012 CVFPP from 2009 through 2011, representing the most comprehensive flood evaluations for the Central Valley. Following the anticipated adoption of the CVFPP in 2012 by the Central Valley Flood Protection Board (Board), preparation of regional- and State-level financing plans will guide investments in the range of $14 billion to $17 billion during the next 20 to 25 years. These financing plans are critical to CVFPP implementation, given the uncertainty in State, federal, and local agency budgets and cost-sharing capabilities.

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Central Valley Flood Protection Plan Update 2017
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Central Valley Flood Protection Plan Update 2017
Department of Water Resources | August 29, 2017...
Summary
The Central Valley Flood Protection Plan (CVFPP) has guided the State’s participation in managing flood risk in areas protected by the State Plan...
The Central Valley Flood Protection Plan (CVFPP) has guided the State’s participation in managing flood risk in areas protected by the State Plan of Flood Control (SPFC) since the plan’s adoption pursuant to the Central Valley Flood Protection Act of 2008 in 2012. A strategic, long-range plan, the CVFPP and its updates describe a programmatic vision for flood system improvements over time in accordance with the requirements of the 2008 Act.

The CVFPP was prepared by the Department of Water Resources (DWR) and adopted by Central Valley Flood Protection Board (CVFPB) through Resolution 2012-25. As conceived by the legislature, the CVFPP is updated every 5 years, beginning in 2017.

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Central Valley Flood Protection Plan: Conservation Strategy

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Central Valley Flood Protection Plan: Conservation Strategy
Department of Water Resources | August 8, 2017...
Summary
In the Central Valley of California, flood risks, water supplies, and the functioning of ecosystems are linked, with actions in one area affecting...
In the Central Valley of California, flood risks, water supplies, and the functioning of ecosystems are linked, with actions in one area affecting the other areas. The majority of flows that pass through the State Plan of Flood Control (SPFC) are regulated by reservoirs operated for flood management, water supply, water quality, power generation, wildlife and fisheries habitat, and recreation. Similarly, the system of river and bypass channels, levees, and water control structures in the Central Valley does more than just contain floodwaters that previously flooded the valley floor for months at a time. It supports agricultural uses in the bypasses, serves as valued recreational areas and open space, helps in the management of surface water supplies and management of groundwater and water quality, and provides critical remnant riparian and floodplain habitats for numerous fish and wildlife species.

The Central Valley Flood Protection Plan (CVFPP) recognizes these interconnections in its approach to flood management. The CVFPP is a long-term planning document that provides a framework for prioritization of investments in the SPFC. It seeks to improve flood risk management (the primary goal), as well as improve operations and maintenance (O&M), promote ecosystem functions, improve institutional support, and promote multi-benefit projects where feasible (supporting goals) (California Department of Water Resources [DWR] 2012a).

This Conservation Strategy (or Strategy) is an integral part of the CVFPP. It supports the attainment of all CVFPP goals, but focuses on the improvement of ecosystem functions through the integration of ecological restoration with flood risk reduction projects where feasible. This Conservation Strategy, including Appendices A?L, describes the basis for recommending various conservation actions and setting long-term objectives for the Central Valley flood management system as a whole. The integration of specific environmental restoration features with DWR’s proposed flood management system improvements is summarized in Chapters 2 and 3 of the CVFPP and will also be described further in the 2017 CVFPP update and supporting documents, such as the Sacramento River Basin-Wide Feasibility Study (BWFS) and the San Joaquin River BWFS.

The Conservation Strategy and CVFPP as a whole would contribute to achieving the California Water Action Plan’s overarching goals of reliability, restoration, and resilience (California Natural Resources Agency, California Department of Food and Agriculture, and California Environmental Protection Agency 2015, 2016). In particular, this Strategy and the CVFPP as a whole are integral to three of the 10 “key actions” identified in the California Water Action Plan:

Increase flood protection.
Protect and restore important ecosystems.
Increase operational and regulatory efficiency.

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Changing Channels: Regional Information for Developing Multi-benefit Flood Control Channels at the Bay Interface
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Changing Channels: Regional Information for Developing Multi-benefit Flood Control Channels at the Bay Interface
San Francisco Estuary Institute | May 26, 2017...
Summary
Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood...
Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood management. The local agencies that oversee these channels are seeking new management approaches that provide multiple benefits and promote landscape resilience. This includes channel redesign to improve natural sediment transport to downstream bayland habitats and beneficial re-use of dredged sediment for building and sustaining baylands as sea level continues to rise under a changing climate.

Flood Control 2.0 is a regional project that was created to help develop innovative approaches for integrating habitat improvement and resilience into flood risk management at the Bay interface. Through a series of technical, economic, and regulatory analyses, the project addresses some of the major elements associated with multi-benefit channel design and management at the Bay interface and provides critical information that can be used by the management and restoration communities to develop long-term solutions that benefit people and wildlife.

This Flood Control 2.0 report provides a regional analysis of morphologic change and sediment dynamics in flood control channels at the Bay interface, and multi-benefit management concepts aimed at bringing habitat restoration into flood risk management. The findings presented here are built on a synthesis of historical and contemporary data that included input from Flood Control 2.0 project scientists, project partners, and science advisors. The results and recommendations, summarized below, will help operationalize many of the recommendations put forth in the Baylands Ecosystem Habitat Goals Science Update (Goals Project 2015) and support better alignment of management and restoration communities on multi-benefit bayland management approaches.

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Clean Water, Clean Beaches Water Quality Funding Measure*

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Clean Water, Clean Beaches Water Quality Funding Measure*
Los Angeles County Department of Public Works, Los Angeles County Flood Control District | September 21, 2012...
Summary
The Problem: Stormwater and runoff rushes down the street, picking up trash and toxic pollutants. On a rainy day, over 10 billion gallons...

The Problem: Stormwater and runoff rushes down the street, picking up trash and toxic pollutants. On a rainy day, over 10 billion gallons of contaminated stormwater flows directly — untreated — into rivers, creeks, lakes and our bay and coastal waters. Polluted stormwater and urban runoff include toxins and pathogens that can affect our health, drinking water supplies, and the health of marine life. Contaminants include: Industrial solvents, paints and chemicals; heavy metals like lead, mercury, chromium and arsenic; infection-causing bacteria; pesticides and fertilizers; and trash like plastics, cigarette butts, candy wrappers and syringes.

*The proposed solution, a parcel tax to fund stormwater remediation and capture projects, failed before the Los Angeles County Board of Supervisors in 2013.

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Delta Region Integrated Flood Management: Key Considerations and Statewide Implications
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Delta Region Integrated Flood Management: Key Considerations and Statewide Implications
California Department of Water Resources (DWR) | September 1, 2012...
Summary
This Background / Reference Memorandum (BRM) presents highlights from flood-related technical, legislative and funding information regarding the Sacramento-San Joaquin Delta (Delta), with emphasis...
This Background / Reference Memorandum (BRM) presents highlights from flood-related technical, legislative and funding information regarding the Sacramento-San Joaquin Delta (Delta), with emphasis on activities by the California Department of Water Resources (DWR).

The BRM is intended to provide historical and existing conditions (year 2011) context for DWR’s use in conveying strategies for future investments in integrated flood management in the Delta under a separate document.

The State of California has entrusted DWR as the agency with the responsibility for managing water flow through the Delta and for representing State interests in Delta levees.

DWR invests in the Delta levee system to protect clear and identifiable State interests, including but not limited to:
• Human life, public health, and property within the Delta;
• Water quality and water supply for agriculture, ecosystem, and municipal and industrial water users within the Delta and water users outside of the Delta;
• Ecosystem protection and enhancement, including protection and recovery of threatened and endangered species;
• Critical infrastructure such as highways, railroads, aqueducts, and pumping plants;
• Other infrastructure such as transmission lines (electric & petroleum), shipping channels, and public infrastructure (water and wastewater treatment plants);
• Agriculture and recreation; and
• Cultural, historical, aesthetic, and other values included in “Delta as a place.”

State legislation and modifications to the California Water and Public Resources codes have repeatedly demonstrated the State’s interest in preserving the Delta and the importance of Delta levees. The legislation and modifications to the codes have made strong statements about the importance of the Delta, provided direction for the DWR’s levee programs, and provided funding for flood management activities and environmental stewardship in the Delta.

This BRM should be considered a reference document. Due to the large number of existing documents on the Delta and its levees, this BRM provides highlights of important material with references to other documents for more detailed information.

This base information should be useful when considering modifications to investment strategies for integrated flood management in the Delta.

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Emergency Response To Flood Threats in California
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Emergency Response To Flood Threats in California
Department of Water Resources | April 8, 2011...
Summary
An explanatory memo on the Flood Operations Branch, Department of Water Resources, Division of Flood Management During the flood season, a number of...
An explanatory memo on the Flood Operations Branch, Department of Water Resources, Division of Flood Management

During the flood season, a number of public agencies combine their efforts to provide high water warnings and minimize flood damage in California. The Department of Water Resources (DWR) is responsible for coordinating local, State and federal flood operations. The State-Federal Flood Operations Center, located on El Camino Avenue in Sacramento, is the focal point of this effort. State, federal and local flood operations on the North Coast streams are coordinated through the DWR Eureka Flood Center in Humboldt County.

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Flood Control System Status Report
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Flood Control System Status Report
Department of Water Resources | December 12, 2011...
Summary
This Flood Control System Status Report (FCSSR) describes the current status (physical condition) of SPFC facilities at a systemwide level. DWR prepared the...
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.

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Flood Management (Resource Management Strategy)
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Flood Management (Resource Management Strategy)
Department of Water Resources | July 29, 2016...
Summary
This resource management strategy report for flood management is unique to the other resource management strategies in that it contains multiple approaches within...
This resource management strategy report for flood management is unique to the other resource management strategies in that it contains multiple approaches within a single resource management strategy report.

Flood management is complex and still relatively new. This flood management strategy provides local and regional water managers a broader perspective of the flood management tools that are available and their interrelationships within one report. In future updates to this resource management strategy report and as flood management becomes more integrated more than one resource management strategy report for flood management could be developed.

This flood management resource management strategy report has been subdivided into four approaches:
• Nonstructural.
• Restoration of natural floodplain functions.
• Structural.
• Flood emergency management.

The report discusses flood management in general terms followed by specific subsections related to the four approaches identified above, as necessary.

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Flood-Risk Reduction and Resilience: Federal Assistance and Programs
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Flood-Risk Reduction and Resilience: Federal Assistance and Programs
Congressional Research Service | November 15, 2017...
Summary
Recent flood disasters have raised congressional and public interest in not only reducing flood risks, but also improving flood resilience, which is the...
Recent flood disasters have raised congressional and public interest in not only reducing flood risks, but also improving flood resilience, which is the ability to adapt to, withstand, and rapidly recover from floods.

In the United States, flood-related responsibilities are shared. States and local governments have significant discretion in land-use and development decisions, which can be major factors in determining the vulnerability to and consequence of hurricanes, storms, extreme rainfall, and other flood events. Congress has established various federal programs that may be available to assist U.S. state, local, and territorial entities and tribes in reducing flood risks.

Among the most significant federal activities to reduce communities’ flood risks and improve flood resilience are

? assistance with infrastructure projects (e.g., levees, shore protection) and other flood mitigation activities that save lives and reduce property damage; and
? mitigation incentives for communities that participate in the National Flood Insurance Program (NFIP).

This report provides an overview of these assistance programs and the NFIP-related mitigation incentives; it also raises flood-related policy considerations associated with federal programs and practices.

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Handbook for Assessing Value of State Flood Management Investments
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Handbook for Assessing Value of State Flood Management Investments
Department of Water Resources | June 8, 2014...
Summary
Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the...
Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the case even as State, federal, and local flood management agencies have worked for decades to reduce the risk and consequences of flooding in the State. The people of California have shown that they understand the increasing flood risk due to population growth, environmental concerns, climate change, and land use practices, and they are willing to invest in flood risk management projects.

This requires the public agencies responsible for California’s flood risk management to demonstrate the value of those investments both before and after they are implemented. This Handbook for Assessing Value of State Flood Management Investments (HAV) supports that effort.

The California Department of Water Resources (DWR) has identified foundational goals that shape the State’s water management investment strategy.

Those goals are:

Improving public safety
Fostering environmental stewardship
Supporting economic stability

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Handbook for Assessing Value of State Flood Management Investments

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Handbook for Assessing Value of State Flood Management Investments
California Department of Water Resources (DWR) | June 1, 2014...
Summary
Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the...

Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the case even as State, federal, and local flood management agencies have worked for decades to reduce the risk and consequences of flooding in the State. The people of California have shown that they understand the increasing flood risk due to population growth, environmental concerns, climate change, and land use practices, and they are willing to invest in flood risk management projects. This requires the public agencies responsible for California’s flood risk management to demonstrate the value of those investments both before and after they are implemented. This Handbook for Assessing Value of State Flood Management Investments (HAV) supports that effort.

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HEC-HMS Models for the Sacramento and San Joaquin River Basins Comprehensive Study

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HEC-HMS Models for the Sacramento and San Joaquin River Basins Comprehensive Study
U.S. Army Corps of Engineers Sacramento District | August 1, 2001...
Summary
Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S....

Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S. House of Representatives directed the Sacramento District to develop comprehensive plans for flood control for the two rivers and to develop hydrologic and hydraulic models of the river systems. The models will be used to provide better forecasts and evaluations of flood damage reduction alternatives. Additionally, the model results will be used as input for reservoir simulation models. The Sacramento River Basin and the San Joaquin River/Tulare Lake Bed Basins comprise nearly 60,000 square miles, drain California’s Central Valley floor and receive much of their runoff from the Sierra Nevada mountain range. Developing hydrologic models for the tributary basins (which included extremely variable terrain) within a ten month time period was a formidable task. The District contacted the Hydrologic Engineering Center (HEC) to assist with the development of these models.

HEC used the Hydrologic Modeling System program, HEC-HMS, and introduced the HEC-GeoHMS grid-based technology to perform the hydrologic study. GeoHMS is an ArcView® extension that provides automated subbasin delineation methods and calculates many physical characteristics used for estimation of hydrologic parameters. HEC developed and calibrated 33 individual HEC-HMS models for the major tributaries and portions of the valley floors of the Sacramento River Basin and the San Joaquin River / Tulare Lake Bed Basins.

GeoHMS was used to delineate the individual river basins, perform initial subbasin delineation and develop the physical characteristics for the subbasins. Tools within GeoHMS allowed the modelers to iteratively redelineate their subbasins, as appropriate, to meet project needs. Keeping the modeling effort consistent was critical to the success of the study. To ensure this consistency of procedures and results, HEC developed modeling guidelines that each of the 11 modeling teams followed.

Once the grid-based HEC-HMS models were developed, HEC contracted with the Corps’ Cold Regions Research and Engineering Laboratory (CRREL) to perform a snowmelt study for the watersheds. HEC provided a gridded precipitation file (4 km2) to CRREL. Through the use of their Distributed Snow Process Model (DSPM), CRREL then provided a gridded snowmelt/ precipitation file to HEC. DSPM computes snowmelt and rainfall depths at the soil surface on a grid-cell basis. This data is used directly by HEC-HMS as precipitation on the watershed. The ModClark rainfall to runoff transformation was used to compute the subbasin hydrographs.

HEC-HMS parameter optimization models were developed at hourly flow gages for the unregulated headwater streams. The runoff parameter optimization models allowed the modelers to develop the runoff parameters necessary for the regression analysis. A number of physical characteristics were evaluated for correlation with variations in Clark’s time of concentration, TC, for the optimization models. The results of the regression analysis allowed the modelers to populate the ungaged subbasins with appropriate unit hydrograph parameters. Approximately 200 hourly flow gages and 83 reservoirs were considered in calibrating the models. The 33 individual basin models were then given to the Sacramento District.

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Implementing California Flood Legislation into Local Land Use Planning: A Handbook for Local Communities
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Implementing California Flood Legislation into Local Land Use Planning: A Handbook for Local Communities
Department of Water Resources | October 1, 2010...
Summary
The potential for flooding is a significant risk for many localities in California. Flood events can cause substantial economic, social, and environmental damage....
The potential for flooding is a significant risk for many localities in California. Flood events can cause substantial economic, social, and environmental damage. In addition, many flood management practices can be costly and have considerable effects on the environment. One of the most effective ways to reduce the vulnerability to potential flooding is through careful land use planning that is fully informed by and reflective of applicable flood information and flood management practices. This Handbook supports the Department of Water Resources (DWR) FloodSAFE California initiative, which is a statewide initiative to improve public safety through an integrated approach to flood management.

Several bills were signed by Governor Schwarzenegger in 2007 adding to and amending State flood and land use management laws. These new laws are intended to improve local land use and other planning decisions by strengthening the link between land use and flood management. The laws contain requirements and considerations that outline a comprehensive approach to improving flood management at the State and local levels.

This Handbook includes the 2007 California flood risk management legislation affecting cities’ and counties’ responsibilities related to local planning requirements such as general plans, zoning ordinances, development agreements, tentative maps, and other actions. It does not address all flood management related legislation passed in 2007. For a complete summary of California flood legislation passed in 2007, refer to the 2007 California Flood Legislation Summary and Companion Reference issued by DWR at http://www.water.ca.gov/legislation/2007-summary.
pdf and http://www.water.ca.gov/legislation/2007-reference.pdf.

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Managing Floods in California
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Managing Floods in California
Legislative Analyst's Office | March 22, 2017...
Summary
This report is intended to provide basic information about floods and flood management in California. (Whereas previous generations referred to “flood control” or...
This report is intended to provide basic information about floods and flood management in California. (Whereas previous generations referred to “flood control” or “flood prevention” activities, experts now prefer the term “flood management” in acknowledgement that floodwaters are recurring and inevitable.) We begin by summarizing the history, causes, and risk of floods across the state. We then describe flood management agencies, infrastructure, and strategies, as well as how governmental agencies typically respond when floods occur. Next, we describe the spending levels and funding sources currently supporting flood management efforts, as well as estimates for how much additional funding may be needed to improve those efforts. We conclude by highlighting some key challenges confronting the state in contemplating how best to manage floods in California.

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Novato Creek Baylands Historical Ecology Study
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Novato Creek Baylands Historical Ecology Study
San Francisco Estuary Institute | July 31, 2015...
Summary
Over the past century and a half, lower Novato Creek and the surrounding tidal wetlands have been heavily modified for flood control and...
Over the past century and a half, lower Novato Creek and the surrounding tidal wetlands have been heavily modified for flood control and land reclamation purposes. Levees were built in the tidal portion of the mainstem channel beginning in the late 1800s to convey flood flows out to San Pablo Bay more rapidly and to remove surrounding areas from inundation. Following levee construction, the wetlands surrounding the channel were drained and converted to agricultural, residential, and industrial areas. These changes have resulted in a considerable loss of wetland habitat, reduced sediment transport to marshes and the Bay, and an overall decreased resilience of the system to sea level rise.

In addition to tidal wetland modification, land use changes upstream in the Novato Creek watershed have resulted in several challenges for flood control management. Dam construction and increased runoff in the upper watershed have resulted in elevated rates of channel incision, which have increased transport of fine sediment from the upper watershed to lower Novato Creek. Channelization of tributaries and construction of irrigation ditches have likely increased drainage density in the upper watershed, also potentially contributing to increased rates of channel incision and fine sediment production (Collins 1998). Downstream, sediment transport capacity has been reduced by construction of a railroad crossing and loss of tidal prism and channel capacity associated with the diking of the surrounding marsh. As a result of the increased fine sediment supply from the watershed and the loss of sediment transport capacity in lower Novato Creek, sediment aggradation occurs within the channel, which in turn reduces the flood capacity of the channel, necessitating periodic dredging (fig. 1; Collins 1998, PWA 2002).

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