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Managing Floods in California
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Managing Floods in California
MAC TAYLOR • L E G I S L A T I V E A N A L Y S T • MARCH 22, 2017
AN LAO REPORT
Cover Photo: The cover photo displays flooding from storms in January 2017,
and was provided courtesy of the California Department of Water Resources.
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TABLE OF CONTENTS
Executive Summary ..............................................................................................................................1
Introduction ..........................................................................................................................................3
Flood History, Causes, and Risk ...........................................................................................................3
Flood Management Responsibilities ..................................................................................................9
Flood Management Infrastructure ...................................................................................................11
Nonstructural Flood Management Efforts .......................................................................................15
Flood Response Activities ..................................................................................................................21
Flood Recovery Programs ..................................................................................................................22
Flood-Related Spending ....................................................................................................................23
Estimated Flood Management Funding Needs ................................................................................28
Key Flood Management Challenges in California ............................................................................29
Conclusion ...........................................................................................................................................33
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EXECUTIVE SUMMARY
Recent months have highlighted how quickly statewide concerns can turn from the devastating
impacts of too little water during a prolonged drought, to the comparably destructive effects of too
much water and resulting floods. Flood management is a complicated and expensive undertaking
in California, given the state’s size, its extensive and aging infrastructure, the number of agencies
involved, and the magnitude of its flood risk. In light of these complexities, this report provides
basic information about floods and flood management in California.
Extensive Flood Risk Across the State. California has experienced destructive flood events
throughout its history. While certain flood disasters from the state’s earlier years—such as the
“Great Flood” of 1862—are famous for their large impacts, California has also experienced
more recent flood events. For example, in the early part of 2017 the Governor declared a state of
emergency in 52 of the state’s 58 counties due to damage from winter storms and floods. All areas
of the state are subject to at least some form of flooding—since 1992, every county in California has
been declared a federal disaster area at least once for a flooding event. Estimates suggest 7.3 million
people (one-in-five Californians), structures valued at $575 billion, and crops valued at $7.5 billion
are located in areas that have at least a 1 in 500 probability of flooding in any given year.
Floods Can Also Have Beneficial Impacts. Despite their potential to cause harmful damage, in
some cases floods can have positive effects for both humans and the environment. Examples of such
benefits include replenishing groundwater basins, creating habitat for fish and wildlife, carrying
and depositing sediments that improve agricultural productivity, and improving water quality by
flushing out contaminants. For these reasons, flood management strategies often incorporate leaving
certain floodplains undeveloped and encouraging flooding in certain areas.
Numerous Governmental Entities Involved in Flood Management Activities. Flood-related
responsibilities are shared across a number of agencies at all levels of government, although most
activities to protect communities from floods—such as establishing land use policies or maintaining
flood infrastructure like levees—are undertaken by local agencies. Local jurisdictions differ in
how they organize flood-related activities, and whether local flood management responsibilities
are assigned to cities, counties, or special districts (such as flood control or reclamation districts).
Federal agencies with significant flood management responsibilities include the U.S. Army Corps
of Engineers (USACE) and Federal Emergency Management Agency, and state agencies include the
Department of Water Resources and Central Valley Flood Protection Board.
The state has special responsibility for—and liability related to—a system of flood protection
infrastructure along the main stem and certain tributaries of the Sacramento and San Joaquin
Rivers, known as the State Plan of Flood Control system.
Both Structural and Nonstructural Approaches Used to Manage Floods. Local, federal, and
state agencies have developed a variety of physical structures to convey and control water flows and
floods. Such structures include levees, weirs, detention basins, dams, seawalls, and bypasses. In
addition to physical infrastructure—which mitigates risk by controlling floods—flood managers also
employ nonstructural approaches that adapt to and accommodate the potential of floods occurring.
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Key nonstructural approaches include (1) adopting land use policies designed to minimize flood
damage, (2) enhancing natural floodplain functions so that undeveloped lands can slow and absorb
floodwaters before they reach developed areas, and (3) preparing ahead of time for how to effectively
respond when a flood does occur.
Billions of Public Dollars Provided Annually for Flood Management Activities. Estimates
suggest that statewide expenditures on flood management activities lie somewhere between
$2 billion and $3 billion annually. As primary responsibility for managing flood risk rests with local
governments, the majority of this funding is generated and spent at the local level from a variety
of revenue sources, including property taxes, assessments, and other taxes and fees. The federal
government also provides several hundred millions of dollars annually for flood management
activities in California, primarily for USACE to undertake large infrastructure projects in
partnership with the state and local agencies. Additionally, the state provides several hundred
millions of dollars annually for flood management activities, largely through voter-approved general
obligation bonds (which are then repaid by the state’s General Fund).
Despite these significant expenditures, several studies have estimated that reducing flood risk
across the state will cost tens of billions of dollars above current expenditure levels over the next
couple of decades.
California Faces Several Key Flood Management Challenges. The state’s extensive flood
management infrastructure is aged and in need of improvements, and it was not designed to
account for evolving statewide goals, scientific knowledge, or conditions. Yet, while additional
investments are required to both maintain and upgrade the existing system, generating funding for
flood management activities can be challenging—particularly at the local level, where the ability
to generate additional tax and assessment revenues is constrained by certain state constitutional
provisions. Moreover, both the state and local governments face challenges in determining how to
balance flood risk with expanding population and development. As the state population grows, so
too does the push to develop into new areas. However, development in flood-prone areas increases
the potential for flood damage. Additionally, the overlapping and fragmented nature of flood-
related responsibilities among various local, federal, and state governments can complicate flood
management efforts and make the process of implementing flood projects exceptionally protracted
and difficult. Addressing these challenges will be key to California’s efforts to effectively manage its
flood risk in the future.
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INTRODUCTION
Recent years have shown how variable $575 billion in structures are at risk of flood
California’s weather and hydrology can be. The damage. However, when managed appropriately,
four-year stretch of 2012 through 2015 was the floods can bring beneficial impacts, including
driest since statewide record-keeping began in enhanced ecosystems, increased future water
1896. Just a year later, 2017 is on track to be among supply, and improved water quality.
the wettest years on record, with precipitation in This report is intended to provide basic
the northern part of the state registering more than information about floods and flood management in
200 percent of normal at the end of February. California. (Whereas previous generations referred
Recent months have also highlighted how to “flood control” or “flood prevention” activities,
quickly statewide concerns can turn from the experts now prefer the term “flood management”
devastating impacts of too little water during a in acknowledgement that floodwaters are recurring
prolonged drought, to the comparably destructive and inevitable.) We begin by summarizing the
effects of too much water and resulting floods. history, causes, and risk of floods across the state.
According to the state’s Hazard Mitigation Plan, We then describe flood management agencies,
“Floods represent the second most destructive infrastructure, and strategies, as well as how
source of hazard, vulnerability and risk, both in governmental agencies typically respond when
terms of recent state history and the probability floods occur. Next, we describe the spending
of future destruction at greater magnitudes than levels and funding sources currently supporting
previously recorded.” Recent incidents of damaged flood management efforts, as well as estimates for
spillways at Oroville Dam and breached levees in how much additional funding may be needed to
the Sacramento-San Joaquin Delta have highlighted improve those efforts. We conclude by highlighting
the state’s dependence on aged flood management some key challenges confronting the state in
infrastructure. One-in-five Californians live in contemplating how best to manage floods in
a flood plain, and state officials estimate that California.
FLOOD HISTORY, CAUSES, AND RISK
Flood History and Impacts due to winter storm and flood damage, and 34
of those counties were declared federal disaster
Long History of Floods Across the State.
areas. (See page 22 for a discussion of federal and
California has experienced destructive flood events
state emergency and disaster declarations.) Since
throughout its history, as highlighted in Figure 1
February 1954, the state has had 50 federally
(see next page). While certain flood disasters from
declared flood disasters, representing nearly
the state’s earlier years—such as the “Great Flood”
two-thirds of all federally declared major disasters
of 1862 and floods along the Los Angeles River
in California over that period.
in the 1930s—are famous for their large impacts,
The variety of locations noted in Figure 1
California has also experienced more recent flood
shows how major flood events are not limited to
events. In early 2017, Governor Brown declared a
certain areas of the state. Rather, the state’s diverse
state of emergency in 52 of the state’s 58 counties
geography means floods occur throughout the
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state and from a number of different causes. Over Dam. Since 1992, every county in California has
the course of one week in February 2017, flood been declared a federal disaster area at least once
evacuations occurred across Northern California, for a flooding event.
from rural San Joaquin County to the urban hub of Floods Have Caused Extensive Damage.
San Jose, as well as for nearly 200,000 people living Throughout the state’s history, flood events
downstream from the storm-damaged Oroville have caused significant damage. Impacts from
Figure 1
Significant Flood-Related Events in California
1825
Los Angeles River Course Change. Flood created by large mountain storms caused the Los Angeles
River to jump its banks, establishing the southerly course it follows today.
1862
“The Great Flood.” Weeks of heavy precipitation created the largest flood in California's recorded history,
lasting several weeks and inundating the entire Central Valley and most of Orange County.
1905
Formation of Salton Sea. Large breaches in irrigation canals inadvertently diverted the Colorado River into
a desert basin in the Imperial Valley, reestablishing a long-dry prehistoric lake.
1917
Authorization of Sacramento River Flood Control Project. Through the Flood Control Act of 1917,
U.S. Congress provided funding to begin developing a system of flood relief structures and bypasses along
the Sacramento River. System eventually expanded to include portions of the San Joaquin River and became
the State Plan of Flood Control (SPFC).
1928
Collapse of St. Francis Dam. Catastrophic failure of dam in Los Angeles County caused flood wave that
killed around 450 people.
1933
Authorization of Central Valley Project. Legislature authorized sale of revenue bonds to construct system
for both water supply and flood control along the Sacramento and San Joaquin Rivers. Project funding and
construction ultimately assumed by federal government.
1938
Southern California Floods. Flash flooding and debris flow from heavy rainfall led the Los Angeles,
San Gabriel, and Santa Ana Rivers to burst their banks, resulting in more than 100 deaths and massive
damage across much of the region.
1941
Los Angeles River Channelization. Destruction from Southern California floods led Congress to enact the
Flood Control Act of 1941, which authorized the U.S. Army Corps of Engineers to begin constructing concrete
channels and dams to control the Los Angeles River’s flows.
1953
Beginning of State Responsibility for SPFC. State signed first of several memorandums of understanding
with federal government, committing to operating and maintaining SPFC facilities.
1955
Yuba City Flood. Feather River overtook its banks and levees on Christmas Eve, destroying much of
Yuba City, nearly destroying Marysville, killing 38 people, and forcing 30,000 people to flee.
1956
Establishment of California Department of Water Resources. Special legislative session called by Governor
Goodwin Knight following Yuba City Flood merged several existing state offices and created new department
for statewide water management.
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the 1862 flood were the most massive in scale: resulting loss of property tax revenue bankrupting
one-quarter of the state’s 800,000 cattle died, the state such that state employees (including the
ultimately contributing to a large-scale shift in Governor and Legislature) were not paid wages for
statewide land use from ranching to agriculture. a year and a half. In more recent history, between
This flood also destroyed one-in-eight homes and 1954 and 2015, federally declared flood disasters
one-third of the state’s taxable property, with the in California claimed 292 lives and resulted in
Significant Flood-Related Events in California (Continued)
1960
Enactment of Burns-Porter Act and State Water Project. Voters authorized $1.75 billion bond to
construct new water conveyance system that would also play a role in statewide flood management.
1964
North Coast Tsunami. Tsunami caused by earthquake in Alaska destroyed several towns in Northern California.
1964
“Christmas Flood.” Severe flooding from heavy precipitation in the northern part of the state, particularly
along the coast. State of disaster declared in 34 counties.
1969
Winter Storms and Floods. Serious flooding from thaw of heavy snowfall across numerous mountain
ranges across the state. Resulted in disaster declarations in 40 counties, 47 people killed, 161 people
injured, and $300 million in economic losses.
1982
Northern California Flooding and Landslides. Massive landslides and debris flows from rainfall throughout
Northern California. Santa Cruz received 25 inches of rain in 36 hours.
1997
“New Year’s Flood.” Major flooding in Central and Northern California from week of heavy rainfall.
Resulted in disaster declarations in 48 counties and $1.8 billion in economic losses.
2003
Paterno Decision. Appellate court found that the state is liable for flood damage in 1986 resulting from
failure of SPFC levee.
2006
Passage of Propositions 1E and 84. Voters authorized $9.4 billion in general obligation bonds for
water-related projects, including $5 billion for flood management.
2007
Enactment of Central Valley Flood Legislation. Passage of legislation including new planning and flood
protection requirements for areas of the Central Valley.
2014
Passage of Proposition 1. Voters authorized $7.5 billion in general obligation bonds for water-related
projects, including $400 million for flood management.
2017
Winter Storms and Oroville Dam Damage. Exceptionally high rates of precipitation caused localized flooding,
mudslides, flood warnings, and road damage around the state. Governor declared state of emergency in
52 counties. Erosion damage to spillways at Oroville Dam led to risk of catastrophic flooding and evacuation
of nearly 200,000 residents.
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759 injuries. While comprehensive data on total disrupting deliveries of fresh irrigation water to
public and private flood-related damage costs 3 million acres of farmland and drinking water to
are not available, state and federal government 25 million people. Similarly, floods that damage
expenditures for flood damage have totaled billions infrastructure important to commerce (such as
of dollars over the past 60 years. Although damage highways, rail lines, or ports) or industry (such as
estimates from the recent winter 2017 floods are information technology companies located along the
still being calculated, the California Department of San Francisco Bay) could have statewide, national, or
Transportation has estimated nearly $700 million international impacts.
just to repair storm damage to highways. In contrast to such negative impacts, in
Floods Can Have Far-Reaching Impacts. some cases floods can have beneficial effects
Besides causing damage to adjacent communities, for both humans and the environment (such as
floodwaters can also negatively affect areas outside creating habitat for migrating fish and birds).
of inundation zones. For example, a flood event For these reasons, flood management strategies
that breaches levees in the Sacramento-San Joaquin often incorporate leaving certain floodplains
Delta could have negative consequences not only for undeveloped and encouraging flooding in certain
Delta farmers and residents, but also communities areas, as discussed later in this report.
far downstream. This is because the Delta is a key
Flood Types and Causes
component in the state’s comprehensive water
delivery system, and a levee breach could result Flood Conditions Vary Across State. Figure 2
in increased salt water flowing into the Delta, summarizes the types of floods that occur in
Figure 2
Types of Flooding in California
Type Regions/Areas Affected Description
Slow rise Statewide, deep floodplains, and Gradual flooding as waterways overflow their banks from
low-lying urban areas heavy precipitation and/or snowmelt.
Stormwater Statewide, localized urban areas Localized flooding during or after a storm, generally
due to blocked storm drain systems failing to properly
convey stormwater runoff.
Flash Statewide, steep slopes, and near Quick-forming and fast-moving floods, often from heavy
streams or creeks rain falling on saturated or dry soil that has poor
absorption ability.
Debris flow Statewide, downstream of Quick-forming and fast-moving floods made up of water,
denuded hillsides liquefied mud, and debris, from rain falling on hillsides
lacking vegetation.
Engineered Statewide, downstream of Flows released due to failure of flood control structures
structure structures such as dams or levees.
Coastal Coast and San Francisco Bay Encroaching seas due to storm surges, high winds,
Area and/or exceptionally high tides.
Alluvial fan Southern and Central California, Shallow and fast-moving floods from rainfall and/or
where canyons fan out from snowmelt displacing sediment along alluvial fans.
mountains
Tsunami Coast High-speed sea waves caused by earthquakes and/or
underwater landslides.
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California, as well as the geographic regions in for greatest damage concentrated in highly
which they typically occur. In general, the figure developed urban areas. Figure 3 (see next page)
displays the different types in order of frequency of shows data compiled by the Department of
occurrence. As shown, some types of floods—such Water Resources (DWR) and U.S. Army Corps
as coastal or alluvial fan—only occur in certain of Engineers (USACE) for the population, value
regions of the state, whereas other types—such as of structures, and crop values located in 500-year
slow rise or flash—can occur throughout the state. floodplains—areas with a 1 in 500 probability
All areas of the state are subject to at least some of flooding in any given year—across different
form of flooding. The variance in flood type, cause, hydrologic regions of the state. (Hydrologic
and likelihood of occurrence is driven by factors regions are the geographic areas encompassing
such as regional weather conditions, hydrologic the drainage of a river or series of rivers.) In total,
conditions, and geology, as well as by human 7.3 million people (one-in-five Californians),
development and engineering. structures valued at $575 billion, and crops valued
at $7.5 billion are located within a 500-year
Flood Risk
floodplain in California.
Flood Risk Defined Based on Estimated Flood The South Coast region (which includes Los
Likelihood. Flood managers define flood risk as the Angeles and San Diego) has the largest exposure,
likelihood of negative consequences or damages with more than 3 million people and structures
occurring from flood inundation. Frequently, flood valued at more than $230 billion located within
risk is described based on the calculated probability the 500-year floodplain. The region has 250,000
that a flood will occur in a given area. For example, residents living within the 100-year floodplain.
a “100-year flood” is estimated to have a 1 in 100 (or Santa Clara, Orange, and Los Angeles are the
1 percent) probability of occurring in any given year. three California counties with both the greatest
Calculated flood probabilities are simply predictions population and the highest structure values located
and are not meant to imply that a 100-year flood, within 500-year floodplains. In contrast, the
for example, will occur only every 100 years. Flood greatest exposure for crop values exists in the three
managers and insurance companies calculate these Central Valley hydrologic regions (Sacramento
probabilities by examining flood hazards (such River, San Joaquin River, and Tulare Lake). Fresno,
as a building’s elevation or proximity to a river), Tulare, and San Joaquin are the counties with the
history (such as how often flooding has occurred largest value of agricultural crops located within
in the past), and flood management structures the 500-year floodplain, together totaling over
(such as the presence and height of levees). While $2 billion.
flood management structures help reduce risk, Human Development Influences Flood Risk.
a floodplain can never be fully protected with Human influences can have both positive and
100 percent certainty. Flood managers sometimes negative effects on flood risk and the magnitude
refer to the remaining risk of damage after of potential damage. Humans have developed
implementation of flood management actions—such extensive flood management structures and
as constructing levees—as “residual risk.” practices to control floodwaters and significantly
Widespread Flood Risk to People, reduce flood occurrences. However, human
Infrastructure, and Crops. Exposure to flood development has also increased the risk for
hazards exists across the state, with the potential potential damage from floods, particularly when
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development takes place in areas that are especially California’s Central Valley offers an example of
prone to flooding. In such cases, flood events that how development decisions have increased impacts
might otherwise have been natural occurrences from floods. This region has experienced many of
with little impact instead can have significant the largest and most destructive floods in the state’s
effects on developed infrastructure. history. This is due in part to the way the course of
Figure 3
Exposure to 500-Year Flood by Region
By Hydrologic Region
NORTH COAST
Residents
40,000
$4 billion
Structures
$90 million
Crop Value
NORTH LAHONTAN
4,000
$1 billion
$10 million SACRAMENTO RIVER
930,000
$70 billion
$1.7 billion
SAN JOAQUIN RIVER
540,000
SAN FRANCISCO
$40 billion
BAY
$1.9 billion
1,040,000
$130 billion SOUTH LAHONTAN
$20 million 150,000
TULARE LAKE $10 billion
500,000 $60 million
$30 billion
$2.3 billion
CENTRAL COAST COLORADO RIVER
430,000 230,000
$40 billion $20 billion
SOUTH COAST
$690 million $280 million
3,140,000
$230 billion
$420 million
Source: California’s Flood Future: Recommendations for Managing the State’s Flood Risk (Department of Water Resources and U.S. Army
Corps of Engineers, 2013).
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the Sacramento River was engineered beginning floodplains, and (3) significant public and private
in the late 1800s to address the by-products of infrastructure existing in close proximity to the
widespread hydraulic mining during the gold rush river. All of these conditions contribute to flood
era. Levees along the river were constructed into risk for valley residents. (As described below, the
narrow channels to help speed river flows in order state has taken various steps to help address this
to flush mining debris out to sea and preserve risk, including strengthening levees and developing
the river’s navigability. Additionally, areas within an extensive bypass system.)
the region that had been natural floodplains have There are other examples across the state where
been “reclaimed” and developed—originally building in areas with particular geographical
for agriculture, but over time increasingly for features has increased the potential for flood
residential and other urban uses. The impacts damage. These include development on hillsides
of these decisions include (1) swift river flows in prone to flash floods, within alluvial fans, or along
narrow channels that place stress on and risk the coast. Rising sea levels are also increasing the
overtopping levees, (2) a river that has been forcibly risk of flood damage for coastal communities.
redirected away from its natural course and
FLOOD MANAGEMENT RESPONSIBILITIES
Numerous Government Entities Involved constructing and maintaining flood infrastructure
in Flood-Related Activities. Responsibilities for such as levees, and emergency preparedness efforts.
managing flood risk and responding to floods have These activities are carried out by various local
evolved over time. In the early decades after the entities, depending upon how agency roles and
state’s founding, flood management fell primarily responsibilities have been assigned and defined in a
to private entities. Local landowners would build particular jurisdiction. In some cases, a city and/or
levees—with varying strategies, materials, and county may assume primary flood management
effectiveness—to direct and divert rivers, streams, responsibilities. In other cases, jurisdictions
and floodwaters. Major flood disasters in the late have established government agencies called
1800s and early 1900s, however, spurred the state special districts—such as flood control, levee, or
and federal governments to play greater roles, reclamation districts—to provide flood-related
including passing flood management policies and services. Other communities have pooled resources
building public flood control infrastructure. As to address regional issues by forming joint powers
shown in Figure 4 (see next page), various flood- authorities. Some special districts and joint powers
related responsibilities are now shared across a authorities have the authority to assess, levy, and
number of local, federal, and state agencies. collect tax revenues to support their activities.
In some communities, various flood
Local Responsibilities
management responsibilities are shared by multiple
Local Government Flood Management agencies, whereas in others a single agency
Arrangements Vary. Statewide, most activities to handles multiple water and flood management
protect communities from floods are undertaken responsibilities. One recent report estimated that
by local agencies. These activities include flood management responsibilities are spread
establishing and implementing land use policies, across over 1,300 local agencies across the state.
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Federal Responsibilities levees of the State Plan of Flood Control (SPFC), the
channelization of the Los Angeles River, and many
USACE. USACE has built, conducts major
of the large dams in the state (including Shasta and
repairs on, and holds regulatory authority over
Oroville). As described later, USACE maintains
certain flood management facilities that were
certain flood regulation authority over many of the
authorized by Congress. The agency, however,
dams it helped construct.
typically hands over operations and maintenance to
Under its Public Law (PL) 84-99 program,
a “nonfederal sponsor” after construction projects
USACE also provides some emergency
are complete. Major flood control projects built in
preparedness assistance to states and local
cooperation with USACE in California include the
Figure 4
Public Agencies With Major Flood Management Responsibilities
Agency Primary Responsibilities
Local
Cities, counties, and Conduct various activities based on local arrangements, including: constructing,
special districts (such maintaining, and improving levees and flood management structures;
as reclamation or flood developing land use policies; developing disaster mitigation and emergency
control districts) response plans; leading emergency response and recovery efforts; and
levying assessments on landowners to fund flood management efforts.
Federal
U.S. Army Corps of Undertake and authorize changes to capital flood protection projects when
Engineers authorized by Congress, generally in partnership with state and local agencies
(including SPFC levees).
Inspect federally constructed levees for compliance with federal standards.
Provide planning and assistance to state and local agencies, including during
flood events.
Provide funding to repair flood-damaged levees if they meet federal criteria.
Establish flood storage and release standards for certain reservoirs.
Federal Emergency Operate National Flood Insurance Program, which includes developing flood
Management Agency hazard maps that define flood risk, establishing floodplain management
standards, and offering federally backed insurance policies.
Provide coordination, assistance, and funding for federally declared flood
disasters.
State
Department of Water Conduct flood forecasting, hydrology, and climatology studies.
Resources Undertake statewide flood management data collection and planning.
Inspect, oversee maintenance of, and in some cases conduct projects on, SPFC
levees. Operate and maintain SPFC dams, channels, and other structures.
Implement flood-related state grant programs.
Help coordinate emergency flood response operations.
Central Valley Flood Ensure that appropriate standards are met for the construction, maintenance,
Protection Board and protection of the SPFC.
Office of Emergency Assist local agencies in responding to floods.
Services Provide coordination, assistance, and funding for state-declared flood emergencies.
SPFC = State Plan of Flood Control.
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communities, including planning, training, including preparing for future floods, forecasting
response exercises, and stockpiling of flood-fight imminent floods, and responding to actual floods.
supplies such as sandbags. Additionally, during Besides providing guidance and assistance to local
a flood event USACE will provide advice, staff agencies, DWR also maintains certain SPFC levees
support, equipment, supplies, and whatever other and facilities.
assistance is requested by state or local flood Central Valley Flood Protection Board
managers. (CVFPB). Formerly called the State Reclamation
Other Federal Agencies Also Involved. Board, CVFPB was created in 1911 to address
The Federal Emergency Management Agency flood issues in the Central Valley. The board holds
(FEMA) plays an important role in providing responsibility, on behalf of the state, for overseeing
disaster assistance during and following a flood the SPFC. Its activities include collaborating
event. Some additional federal agencies not with other agencies to improve the SPFC’s flood
highlighted in Figure 4 also play supporting roles protection structures, issuing permits for work
in flood management activities. These include the on the system’s levees and structures, enforcing
U.S. Environmental Protection Agency, which sets removal of problematic levee encroachments, and
stormwater discharge standards, and the Bureau serving as the intermediary between USACE and
of Reclamation, which operates some dams as SPFC permit applicants.
part of the Central Valley Project. Additionally, Other State Agencies Also Involved. Like
the U.S. Fish and Wildlife Service and National FEMA, the state’s Office of Emergency Services
Marine Fisheries Service monitor and regulate the (OES) provides disaster assistance during and after
potential impacts of flood management efforts on a flood event. The State Water Resources Control
fish and wildlife and issue permits for certain flood Board and regional water boards set and regulate
projects. The U.S. Geological Survey collects and stormwater discharge requirements. The California
disseminates flood-related data, including real-time Department of Fish and Wildlife monitors
streamflow and runoff rates, as well as maps that and regulates the potential impacts of flood
model potential flood inundation patterns. The management efforts on fish and wildlife, including
Federal Energy Regulatory Commission sets issuing permits for certain projects. Additionally,
some operational requirements for dams that also the Delta Stewardship Council evaluates flood
produce hydroelectric power. projects proposed within the Delta to ensure they
are consistent with established state goals for the
State Responsibilities
region, and is developing a Delta Levees Investment
DWR. DWR is the state’s lead agency in flood- Strategy to guide the state in prioritizing levee
related activities. The department’s responsibilities funding.
include the full cycle of flood-related activities,
FLOOD MANAGEMENT INFRASTRUCTURE
In this section, we discuss the physical of flood-related facilities, then provide additional
structures developed for managing floodwaters detail on the SPFC system for which the state has
in California. We begin by providing an overview special responsibilities.
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Overview of Physical Flood These statewide totals also include 1,600 miles
Management System of levees and four dams in the Central Valley that
are overseen by the state and considered part of the
Many Types of Flood Management Facilities
SPFC system. With the exception of several dams
Across State. Local, federal, and state agencies have
operated by USACE or the Bureau of Reclamation,
developed a variety of physical structures to convey
the federal government generally does not directly
and control water flows and floodwaters. Such
operate or maintain many flood control facilities in
structures include levees and floodwalls, channels,
California.
weirs, and culverts. Additionally, flood managers
Water Supply Facilities Also Play Role in
use detention and retention basins, dams and
Flood Management. In addition to structures
reservoirs, and bypasses to collect or store water
built explicitly to manage floods, other water-
and thereby regulate flood flows. Seawalls and
related facilities across the state are used for flood
breakwaters are used to armor the shoreline against
management. For example, components of the State
coastal flooding. Figure 5 defines and illustrates
Water Project and federal Central Valley Project—
some key flood infrastructure components.
including dams such as Oroville and Shasta—are
Physical structures—like levees and weirs—
operated not only for water supply purposes,
are also sometimes paired with nonstructural
but also to store and release water to minimize
approaches—like the use of floodplains—for flood
downriver flood risk during storms and periods of
management. Additionally, flood management
high snowmelt. This is also true of many local dams
structures—such as dams and reservoirs—
and reservoirs.
frequently are also used for water supply purposes,
USACE maintains flood control authority over
as discussed below.
around 20 reservoirs in California that are owned
Most Flood Infrastructure Locally Owned
and operated by other governmental agencies but
and Managed. Flood management infrastructure
for which construction was partially federally
across California includes more than 20,000 miles
funded. These include some of the largest reservoirs
of levees and channels and more than 1,500 dams
in the state, including Shasta, Oroville, New
and reservoirs. Most of these facilities are owned
Melones, and New Don Pedro. Specifically, USACE
and managed by local governments. This reflects the
has computed a specific amount of “flood control
history of how most of the facilities were developed,
space” that must be maintained within these
aligns responsibility with beneficiaries (because
reservoirs to capture runoff and avoid exceeding
local communities generally have the most to lose or
the maximum capacity of the dam or harming
gain from the efficacy of flood management actions),
downstream entities. USACE can require dam
and is consistent with ownership of most public
operators to release water from these reservoirs to
infrastructure across the state. Large locally owned
ensure this amount of storage capacity is reserved
flood projects around the state include concrete
for flood safety—for example, if a storm is forecast
channels and dams on the Los Angeles River
and additional runoff is projected to flow into the
(managed by the Los Angeles County Department
reservoir.
of Public Works) and the Santa Ana River (managed
by the Orange County Public Works Division).
SPFC
Additionally, some levees in the state, particularly
SPFC Provides Flood Protection in Central
in very rural areas and along smaller streams, are
Valley. The SPFC is a system of flood protection
privately owned and maintained.
12 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
infrastructure along the main stem and certain four dams, five major weirs, seven major drainage
tributaries of the Sacramento River and the San pumping plants, and seven bypasses that are used
Joaquin River, as shown in Figure 6 (see next page). to divert water during periods of high flow. These
The system includes about 1,600 miles of levees, features have been built over time and by multiple
Figure 5
Illustration of Key Flood Infrastructure Components
Reservoir
River Lake created by water
impounded behind dam.
Dam
Barrier constructed to hold
back water and regulate flows.
Levee
Embankment alongside river,
usually earthen, built to contain
or control water flows.
Weir
Low wall built to alter the
speed or direction of the
water as it flows over.
Stream
Detention Basin
Pond designed to temporarily
capture stormwater runoff to
prevent localized flooding.
Flood Bypass
Land area designed to convey
floodwaters, for example away from
populated areas, and reduce flows
in main river path.
Seawall
Shoreline wall or embankment constructed to
hold back waves and prevent erosion and flooding.
Ocean
www.lao.ca.gov Legislative Analyst’s Office 13
AN LAO REPORT
Figure 6
State Plan of Flood Control (SPFC)
!
Redding
Map
Extent
CCAALLIIFFOORRNNIIAA
r Lake
v e Oroville
§¨¦ Ri
o
5 nt
e
m
a
r
ca
S
!
Yuba City
§¨¦
80
!
§¨¦ Sacramento
80
!
Stockton
San Francisco !
S
a
n
J
o
a
q
u
in
R
iver
SPFC Levees
¬
0
Scale
1
In
5
Miles
30
Califor
§¨¦
niaAqu
SanJ
F
oa
r
q
e
u
s
in
n
R
o
iver
!
5
educt
Source: California Department of Water Resources.
14 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
entities, beginning with private citizens creating operations and maintenance responsibilities.
levees out of local sands and soils in the mid-1800s. These responsibilities include conducting daily
Federally authorized flood control projects to inspections, ensuring levees stay structurally
improve the SPFC—undertaken by USACE—began sound and meet standards, clearing excessive
in 1917 in the Sacramento River basin and in 1944 vegetation, and undertaking projects to improve
in the San Joaquin River basin. levee effectiveness. DWR maintains approximately
State Responsible for—but Local Agencies 300 miles of SPFC levee segments not covered by
Primarily Maintain—SPFC. Although many SPFC such agreements.
components were locally or federally constructed, Paterno Court Decision Established State
in the 1950s the state committed to the federal Liability for SPFC. In 2003, a state appellate court
government that it would oversee the SPFC system found the state responsible for a SPFC levee failure
and maintain its facilities pursuant to federal along the Yuba River, thereby establishing a new
standards. (SPFC levees are also commonly referred standard for the state’s flood liability. The 2003
to as “project levees,” in reference to the SPFC being decision in the Paterno v. California case found
a joint state and federal project.) Only levees and that the state had failed to properly maintain the
structures along certain tributaries and stretches Linda Levee (located south of Marysville) and
of river are considered part of the SPFC system therefore was liable for resulting flood damage
and subject to this state-federal agreement. The when it failed in 1986. Although the levee was
state has not assumed responsibility for all flood both originally constructed and maintained at
protection facilities in the Central Valley. For the time by local entities—not the state—and
example, within the 1,100 miles of levees located reportedly had never met engineering standards,
in the Sacramento-San Joaquin Delta, only about the court found that the state undertook liability
380 miles are part of the SPFC—the remaining when it assumed control of the SPFC in the 1950s.
720 miles are locally owned and maintained. Specifically, courts found that the state “had ample
CVFPB oversees SPFC facilities on behalf of the opportunity to examine” and repair the levee. The
state, including issuing permits for modifications state eventually paid a $464 million settlement to
and enforcing that levees are maintained up the nearly 3,000 plaintiffs. The Paterno decision’s
to required standards. For most segments of precedent makes it possible that the state could
SPFC levees, the state has developed formal ultimately be held responsible for the structural
agreements with local governments (primarily integrity of all SPFC facilities.
local reclamation districts) to handle regular
NONSTRUCTURAL FLOOD MANAGEMENT EFFORTS
In contrast to physical infrastructure—which Land Use Policies
mitigates risk by controlling floodwaters—
Land Use Policies Can Seek to Minimize
nonstructural management approaches adapt
Potential Damage. A key nonstructural approach
to and accommodate the potential of floods
to limiting damage from floods is to control the
occurring. In this section, we describe three major
amount and type of development that occurs in
nonstructural approaches: land use policies,
flood-prone areas. For example, jurisdictions might
floodplain restoration, and emergency preparation.
www.lao.ca.gov Legislative Analyst’s Office 15
AN LAO REPORT
develop land use policies and building codes that in those areas to have flood insurance in order
discourage construction within floodplains. Other to be eligible for a federally backed mortgage.
policies might allow development but require Additionally, participation in the federal National
that buildings be elevated to a certain height to Flood Insurance Program (NFIP) is only available
withstand flooding. in communities that have agreed to adopt and
Federal and State Policies Can Influence enforce local ordinances that meet or exceed
Local Land Use Decisions. Land use decisions are federal floodplain management standards. (Please
made primarily by local governments. However, see the nearby box for more detailed information
in some cases, they can be influenced by federal about NFIP.) Thus, while local jurisdictions are not
and state policies. For example, the federal required to meet federal standards for restricting
government identifies areas with a high risk of development in flood-prone areas, federal policies
flooding and requires home and business owners strongly encourage them to do so, in order to avoid
National Flood Insurance Program (NFIP)
Program Intended to Reduce Flood Impacts. Congress established the NFIP in 1968 to address
a number of policy objectives, including (1) offering affordable insurance premiums to residents in
flood-prone areas, (2) reducing federal disaster assistance costs, (3) encouraging better community-
based floodplain management, and (4) identifying flood risk across the nation. Under the program,
private insurance companies sell and service federally backed flood insurance policies to private
property owners. The NFIP is funded through roughly $3.5 billion in annual insurance premium
revenues and, when necessary to cover claim payments, loans from the U.S. Treasury. The program
currently owes over $20 billion to the Treasury due to substantial hurricane-related claims in
2005 and 2012.
Flood Insurance Required in Certain Circumstances. While federal law does not explicitly
require property owners to purchase flood insurance, it does require that federally regulated or
insured mortgage lenders mandate flood insurance as a loan condition for buildings located in
high-risk flood areas—making it a de facto requirement for certain home and business owners.
Additionally, property owners who receive federal disaster assistance after a flood must purchase
flood insurance to remain eligible for future disaster relief. The Federal Emergency Management
Agency (FEMA), which manages the NFIP, creates maps classifying flood hazard risk as high,
moderate, or low based on various characteristics including geography, elevation, and flood history.
High-risk areas have at least a one-in-four chance of flooding during a 30-year mortgage.
Mortgage lenders can also require that borrowers purchase flood insurance for non-federally
backed loans and/or for properties in low- or moderate-risk areas. Indeed, FEMA notes that over
20 percent of all flood insurance claims come from areas outside of mapped high-risk flood zones.
Even when not required by their lenders, some property owners opt to purchase flood insurance, as
flood damage is not typically covered by traditional homeowner’s insurance.
Eligibility Dependent on Local Flood Management Actions. Federally backed NFIP policies are
only available for buildings located in communities that have agreed to adopt and enforce
16 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
limiting mortgage financing options for their local NFIP—200-year protection rather than 100-year
property owners. protection. They can meet these requirements
Similarly, the state has adopted certain policies either by limiting development or by building or
designed to encourage local jurisdictions to avoid improving structural flood infrastructure such
making land use decisions that increase flood risks. as levees. While state policies encourage local
For example, several such policies were included actions to limit flood damage, these policies have
in a package of flood-related legislation passed in some notable limitations. Specifically, the policies
2007, as summarized in Figure 7 (see next page). (1) only apply to the Central Valley, (2) only pertain
The legislation states that local governments in to new development, and (3) are self-enforced by
urban areas of the Central Valley shall plan for local governments (with repercussions for lack of
an even higher level of protection than the federal compliance somewhat unclear).
floodplain management standards required by the
local ordinances that meet or exceed FEMA floodplain management standards. FEMA’s standards
are designed to reduce flood damage, such as requirements that new development does not cause
obstructions to the natural flow of floodwaters or increase flood risk for neighboring properties.
To encourage even more effective floodplain management, FEMA offers reduced flood insurance
premiums through its Community Rating System program for communities that exceed its
minimum standards.
California’s Participation Somewhat Limited. As of September 2016, Californians held around
296,000 NFIP policies—about 6 percent of the nationwide total. By comparison, Florida residents
held 35 percent of national NFIP policies, and Texas represented 12 percent of the nationwide total.
(Data regarding the number of properties in high-risk areas in each state are not readily available.)
NFIP participation rates in California declined in recent years, likely because the state had been in
a drought and had not experienced a major flood for several years so residents had a lower perceived
risk. These numbers likely have increased in recent months as a result of winter 2017 floods, though
associated data are not yet available. According to researchers at the University of California, Davis
(UC Davis), as of October 2016, California’s NFIP policies cover $82.6 billion of insured assets and
are supported by $213 million in annual premiums payments.
Between October 2015 and September 2016, NFIP policyholders in California submitted
337 insurance claims and received about $4.6 million in claim payments—representing less than
1 percent of both claims and payments nationwide. The UC Davis researchers found that between
1994 and 2014, NFIP damage payouts in California totaled just 14 percent of the amount its
residents paid in premiums—an imbalance of over $3 billion, adjusted for inflation. By comparison,
North Dakota had the highest rate of NFIP payments as a percentage of the amount paid in
premiums—188 percent—over that 20-year period. (These data exclude each state’s single largest
claim year to avoid skewing the data with a single catastrophic event, otherwise Mississippi would
be the greatest net NFIP beneficiary.)
www.lao.ca.gov Legislative Analyst’s Office 17
AN LAO REPORT
Federal Government Recently Increased • Build the structure at an elevation that is
Standards for Federally Funded Construction. In above the projected 500-year flood level.
January 2015, the federal government announced
• Build the structure at an elevation that
new flood standards for building federally funded
is two feet above the projected level of a
structures such as buildings or roads. The new
100-year flood for standard projects, and
standards apply when federal funds are used to
three feet above for critical buildings like
build or significantly retrofit or repair structures
hospitals and evacuation centers.
and facilities in and around floodplains. The
standards are somewhat flexible, allowing agencies
• Build the structure based on data and
to choose one of three options for how their
methods informed by the best-available,
projects comply:
actionable climate science.
Floodplain
Figure 7
Preservation,
Major Components of 2007
Expansion, and
Central Valley Flood Legislationa
Restoration
9
State Planning Requirements. Required DWR and CVFPB to prepare, Floodplains Can
adopt, and implement a CVFPP by 2012, then update that plan every five
years. The plan must include (1) a description of existing flood risk and Help Keep Floodwaters
facilities within the SPFC area, (2) an evaluation of the improvements Away From Development.
necessary to bring SPFC facilities up to current design standards,
Nonstructural approaches
and (3) recommendations for improving the SPFC’s performance that
incorporate multiple benefits (such as to the ecosystem). also include preserving
9 and enhancing natural
Local Planning Requirements. Required Central Valley cities and
floodplain functions
counties to (1) develop flood emergency response plans and (2) amend
general plans to conform to the data, policies, and implementation such that undeveloped
measures included in the CVFPP, including adopting goals and policies
lands can slow and
intended to protect lives and property and reduce flood risk.
absorb floodwaters before
9
Higher Flood Protection Standards. Established 200-year flood event they reach developed
(flood with a 1-in-200 chance of occurring in any year) as the minimum
areas. Actions include
level of flood protection to be provided for new development in urban and
urbanizing areas. purchasing easements
to preserve lands so
9
Local Zoning and Development Requirements. Required Central they remain available
Valley cities and counties to amend zoning ordinances to conform to the
for periodic inundation,
CVFPP and to their amended general plans, including by prohibiting new
development in areas not protected up to the 200-year flood standard. or setting back levees
9 and widening channels
State Mapping and Notification Requirements. Required DWR and
to allow the river
CVFPB to (1) map flood risk areas in the Central Valley, (2) prepare levee
flood protection zone maps, and (3) annually notify applicable property greater access to its
owners that they live in a flood zone protected by a levee.
original floodplain and
a
Chapters 364 (SB 5, Machado); 365 (SB 17, Florez); 366 (AB 5, Wolk); 367 (AB 70, Jones);
368 (AB 156, Laird), and 369 (AB 162, Wolk) of 2007. accommodate a higher
DWR = Department of Water Resources; CVFPB = Central Valley Flood Protection Board;
volume of flows. Efforts
CVFPP = Central Valley Flood Protection Plan; and SPFC = State Plan of Flood Control.
can also be undertaken to
18 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
improve the effectiveness of existing floodplains, Bypass instead of through the main stem of the
such as removing vegetation or sediment that river near the City of Sacramento.
impede floodwater flows. (Please see the nearby Floodplains Provide Additional Benefits.
box for two examples of recent efforts to restore Utilizing floodplains can provide benefits beyond
floodplains in order to reduce potential damage to just reducing the risk of flood damage. One
urban areas.) Another approach to accommodating example of a positive impact is percolation of water
natural floodwaters is to cultivate wetlands along into the ground, helping to replenish groundwater
shorelines to serve as buffers to high tides or surges. basins for future agricultural and residential uses.
Specifically, wetlands can absorb and dissipate Additionally, inundation in natural floodplains can
seawater surges before they reach and inundate improve habitat conditions for plants and wildlife,
near-shore development. such as by providing seasonal flows and creating
Bypasses Use Flood Structures to Convey wetlands needed by migrating fish and birds. For
Waters Into Floodplains. Flood bypasses combine example, recent experiments found that juvenile
structural approaches to control floodwaters with salmon raised in the flooded Yolo Bypass grew
the nonstructural approach of utilizing natural much faster and bigger than those in the main stem
floodplain functions. Specifically, levees and weirs of the Sacramento River. Sediments carried and
are used to direct waters out of river channels into deposited by flood waters can also enrich soils for
large floodplains—“bypassing” the normal path agricultural purposes. Finally, floodplains can help
of the river—so the water can spread and the flow dilute and flush out pollutants and contaminants
velocity can dissipate. Bypasses are a particularly and thereby improve water quality when the flows
important part of the SPFC system, which includes join streams, rivers, and the ocean.
seven “relief” bypasses. During periods of high Increasing Shift to Multi-Benefit Flood
water flows, more than 80 percent of Sacramento Management Approach. Flood managers,
River waters can end up flowing through the Yolo particularly at the state and local levels, have
Two Examples of Floodplain Restoration Efforts
Floodplain restoration efforts are being implemented across the state. One example of an effort
to enhance floodplain capacity is currently underway in West Sacramento. The Southport Levee
Setback Project—a collaborative effort between the City of West Sacramento, the local flood control
agency, the Department of Water Resources, and the U.S. Army Corps of Engineers—will set back
four miles of the existing levee on the Sacramento River. This will expand the river’s width, allowing
it greater access to its original floodplain, as well as create 152 acres of new riparian habitat.
Another example is the Napa River/Napa Creek Flood Protection Project, which utilized
strategies including (1) riverbank terracing (allowing rising floodwaters room to spread into defined
areas), (2) converting pastureland to wetlands that are available to hold excess waters, (3) replacing a
number of old bridges that had blocked flows, and (4) incorporating a dry bypass channel to provide
a shortcut for fast-moving water that historically had overtopped the normal pathway of the river.
The bypass, completed in 2015, flooded for the first time in February 2017 and helped prevent the
type of widespread flooding in downtown Napa that occurred during storms in 2005.
www.lao.ca.gov Legislative Analyst’s Office 19
AN LAO REPORT
made efforts in recent years to encourage flood Management projects. This program provides
management projects that take advantage of grants for regionally driven multi-benefit projects
the multiple benefits associated with natural that often pair flood-related activities with other
floodplain functions. Recent statewide planning water management goals such as water supply.
documents—including California’s Flood Future:
Emergency Preparation
Recommendations for Managing California’s Flood
Risk (2013), The Water Action Plan (2014), and Another nonstructural approach that can
the Central Valley Flood Protection Plan Update minimize life and property loss from floodwaters is
(2017)—emphasize the need for an integrated to plan ahead for how to effectively respond when a
water management approach. These plans highlight flood does occur.
that in addition to protecting public safety, Both Federal and State Laws Include Some
flood management projects also can and should Flood Emergency Planning Requirements. In
achieve additional benefits such as ecosystem order to remain eligible for some federal funding,
restoration, wildlife habitat development, and local jurisdictions are required to plan for flood
groundwater recharge. One component of the emergencies and mitigate flood risk. For example,
Central Valley Flood Protection Plan Update, the maintaining eligibility for certain federal disaster
“Conservation Strategy,” identifies specific tools assistance grants requires local jurisdictions to
and approaches that should be incorporated into develop—and submit to FEMA for approval—
local flood management plans to restore natural local hazard mitigation plans. For areas in
areas in ways that benefit fish and wildlife. FEMA-identified flood hazard zones (as described
Specifically, the document describes (1) targeted earlier with relation to the NFIP), these plans must
species to assist (such as Central Valley spring-run include flood mitigation strategies.
Chinook salmon), (2) ecological objectives to The 2007 flood legislation referenced earlier
pursue (such as increased shaded riverine aquatic also included some state-level flood planning
cover), (3) environmental stressors to address requirements for Central Valley residents.
(such as invasive species or fish passage barriers), Specifically, for a local levee-maintaining agency
(4) potential approaches to implement (such as to be eligible for state funds to improve an SPFC
relocating levees), and (5) strategies for facilitating levee, the local jurisdiction located behind the levee
such approaches (such as streamlining and must develop a flood safety plan. This plan must
coordinating project permitting requirements). include (1) flood preparedness measures, including
The state has also structured certain funding storage of materials that may be used to reinforce
grants to encourage or require multi-benefit flood or protect a levee; (2) a levee patrol plan for high
management projects, including projects funded by water events; (3) anticipated flood-fight procedures;
Proposition 1, the 2014 water bond. For example, (4) an evacuation plan, including for schools and
Proposition 1 included $395 million for flood- elderly care facilities; and (5) a floodwater removal
related projects and explicitly required that “funds plan. (The FEMA plan can be used to meet this
shall be allocated to multibenefit projects that state planning requirement provided it contains all
achieve public safety and include fish and wildlife of the necessary elements.)
habitat enhancement.” Recent water bonds— Effective Local Preparation Can Help Reduce
including Proposition 1—have also included a Flood Impacts. Preparedness activities include
total of $2.3 billion for Integrated Regional Water training local emergency responders, developing
20 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
systems or purchasing equipment for emergency “floodproof” structures so they are prepared to
communication, establishing and communicating handle occasional floodwaters. For example, this
evacuation procedures, and acquiring flood-fight could include raising the structure’s elevation
material stockpiles such as sandbags. Flood by building impermeable walls and entry points
managers also prepare for potential responses (“dry” floodproofing), or by ensuring anything
to particular flood conditions—for example, located on the ground floor can get wet (“wet”
by developing engineering plans for making floodproofing).
emergency relief cuts in levees to relieve pressure Increasing Warning Time Can Improve
from floodwaters. Understanding potential Ability to Respond. The state has also undertaken
resulting impacts of such actions ahead of time can efforts to improve its flood-forecasting ability
allow them to be undertaken quickly in emergency in order to provide flood managers and local
situations. communities with additional warning time to
Flood managers also help educate individuals respond to potential floods. These proactive
on how they can prepare for floods to minimize efforts have included improving stream gauges
risk. For example, individual residents can have and sensors to get real-time flow information and
emergency supplies prepared and develop family improving communication procedures to shorten
evacuation plans. Farmers can plan for how to the length of time between when a flood threat is
quickly get their livestock to higher ground. determined and when the public is notified.
Individuals, businesses, or farmers can also
FLOOD RESPONSE ACTIVITIES
Flood Response Typically Has Four Stages. • Mitigation actions by both governmental
The governmental process for responding to an agencies and local residents. These
imminent flood typically consists of four stages: might include undertaking evacuations,
deploying flood-fighting teams, applying
• Detection by flood managers that a flood
sandbags, or removing sensitive equipment
could occur, informed by weather forecasts
to higher ground.
and flow gauges on rivers and streams.
As noted above, increased warning time before
• Decision-making by local emergency
a flood occurs can improve response effectiveness,
responders regarding what immediate
thereby reducing the potential loss of life or damage
response steps and mitigation actions will
to property. As such, state and local jurisdictions
be implemented to minimize the potential
make efforts to minimize the amount of time spent
property damage and loss of life.
on the first three steps so that mitigation efforts
• Notification of the public—through can be implemented as soon as possible before
methods such as automated phone and floodwaters hit.
text alerts—about the flood threat and Emergency Response Typically Collaborative
the recommended or required response Effort. Emergency response often entails the
actions. collaboration of multiple levels of government.
Local governments are typically the first entities
www.lao.ca.gov Legislative Analyst’s Office 21
AN LAO REPORT
to respond to disasters—such as floods—affecting local governments typically seek support from
their communities. When faced with flooding, local the state government through OES. OES provides
governments take various actions to protect public various types of support to local governments
safety and mitigate damage to public and private responding to floods, including coordinating the
infrastructure. For example, they frequently deploy provision of additional resources—such as staff and
local government staff—such as law enforcement or equipment—from other jurisdictions through the
firefighting personnel—to provide on-the-ground state’s system of mutual aid. OES also coordinates
disaster response. Additionally, if necessary, local the emergency response activities of DWR and all
governments will activate their local emergency other state agencies to ensure that state resources
operations center, which serves as a centralized are provided as needed. Finally, when a flood event
location for staff to coordinate emergency activities, is significant, OES coordinates with the federal
such as tracking and securing disaster response government to ensure that the state receives federal
resources and sharing information. assistance, such as supplies and personnel. OES
Many flood events are handled entirely at the maintains Regional Operations Centers as well
local level, without the assistance of the state or as State Operations Centers, which it activates, as
federal government. However, when floods are necessary, to facilitate its disaster coordination
large enough to exceed local capacity to respond, efforts.
FLOOD RECOVERY PROGRAMS
State and Federal Programs Provide Certain State of Emergency and, through OES, provide
Post-Flood Assistance. The state and federal funding to the affected local jurisdiction through
governments provide disaster recovery programs CDAA. While there is no specific dollar threshold
through the California Disaster Assistance Act for the amount of damage to qualify for CDAA
(CDAA) and Stafford Act, respectively. These funding, OES typically provides local governments
programs provide financial and other forms of with assistance when it determines that local
assistance to public agencies and—in some cases— financial capacity has been exceeded. A variety
to individuals following a disaster such as a flood. of types of local government costs are eligible for
For both programs, a first step in the process is for reimbursement under CDAA, such as emergency
the local, state, and federal agency representatives, response personnel overtime costs, infrastructure
as relevant, to conduct a Preliminary Damage repair and replacement costs, and certain
Assessment in order to determine the extent of the administrative costs. CDAA typically covers no
damage from the disaster. more than 75 percent of eligible costs, with the
State Assistance Provided Through CDAA relevant local agency covering the remaining
Based on Request From Local Government. If a 25 percent of eligible costs. These ratios apply to
local jurisdiction experiences a flood disaster that both state-declared eligible disaster costs, as well
exceeds its ability to respond, local officials can as to the nonfederal share of federally declared
declare a local emergency and request assistance disaster costs, as described below. CDAA does not
from the Governor. Depending on the amount typically pay any funding for individual losses.
of damage, the Governor may declare an official
22 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
Federal Recovery Assistance Based on Request provides disaster assistance funding for a somewhat
From State. If the Governor determines that broader range of activities than CDAA, including
the flood disaster exceeds both local and state some limited individual assistance. The federal
capacity, he or she can request a federal disaster government typically covers 75 percent of eligible
declaration and disaster assistance from the public recovery costs, with the nonfederal share
President. If this request is granted, the federal covered by the state (18.75 percent) and local
government typically provides affected state and governments (6.25 percent). In addition, the federal
local governments with disaster assistance when Small Business Administration provides disaster
certain per capita dollar thresholds for damage recovery loans to individuals and businesses to
are reached. The federal government may also repair and replace damaged or destroyed property.
consider various other factors—such as a state’s (We describe state and federal funding programs in
history of disasters—when determining whether greater detail below.)
to provide assistance. The federal government
FLOOD-RELATED SPENDING
In this section, we discuss overall flood Estimates for Current Flood Expenditures.
management and response expenditures, including Despite these difficulties, some estimates exist for
the amounts and types of funding supporting these current flood-related expenditures in California.
activities from state, federal, and local sources. Specifically, California’s Flood Future, a report
produced by DWR and USACE in 2013, estimated
Overall Spending
average annual statewide expenditures on flood
Flood-Related Expenditure Data Difficult to management between 2000 and 2010 to be
Delineate. Estimating how much funding supports $2.8 billion. A 2014 report by the Public Policy
flood management efforts is difficult for several Institute of California (PPIC), Paying for Water
reasons. First, as described earlier, such efforts in California, had a slightly lower estimate for
are undertaken by a multitude of agencies at the a more recent time frame: $2.2 billion annually
local, federal, and state levels. Second, expenditures between 2008 and 2011. Figure 8 (see next page)
for large flood management projects—such as displays the estimates from these two reports. The
reengineering levees or expanding floodplains—can differences between the estimates probably reflect
stretch over several years and involve multiple a combination of the different methodologies
funding partners, sources, and mechanisms. Third, and time frames used, as well as some of the data
activities that provide flood-related benefits may challenges discussed above.
have other primary or secondary water management
Local Government Spending
goals, such as ecosystem restoration or stormwater
management. For example, a local project to capture As primary responsibility for managing flood
stormwater in underground basins might reduce risk rests with local governments, the majority
flood risk but also decrease the pollution flowing of funding for flood management activities is
into streams and increase local water supplies. generated and spent at the local level. DWR/USACE
Determining what share of this project to “score” as estimated that local funding for flood-related
a flood-related expenditure is difficult. activities averaged $2 billion annually between
www.lao.ca.gov Legislative Analyst’s Office 23
AN LAO REPORT
sales taxes), special taxes (which could be dedicated
Figure 8
just for flood or for a range of water management
Two Recent Studies Estimate
activities), revenues from water sales or service
Statewide Flood-Related
Spending by Source charges (often included in local water bills), fees
(such as development impact fees), and proceeds
(Average Annual Spending in Millions)
from locally issued bonds.
DWR/USACE PPIC
2000-2010 2008-2011 PPIC conducted an analysis of data from
special districts (not including cities or counties)
Spending
Local $2,040 $1,324 and found that on average between 2008 and 2011,
Federal 470 254
property taxes were the single largest local revenue
State 330 574
source for flood-related activities each year (just
Totals $2,840 $2,152
over one-third of total revenues). Revenues from
DWR = Department of Water Resources; USACE = U.S. Army
Corps of Engineers; and PPIC = Public Policy Institute of California.
sales or service charges made up about one-fifth of
Sources: California’s Flood Future; Recommendations for
Managing the State’s Flood Risk (DWR/USACE, 2013); and flood-related revenues, with various other sources
Paying for Water in California (PPIC, 2014).
comprising the remainder.
Level of Local Special District Expenditures
2000 and 2010. PPIC’s estimate for 2008 through
Varies Across the State. PPIC found that per
2011 was $1.3 billion a year.
capita flood spending from special districts varied
Local Agencies Rely on Variety of Funding
significantly across regions of the state. (Data were
Sources for Flood Protection. Local governments
not available for cities and counties that have flood
generate revenues for flood management
management responsibilities.) The researchers
activities—including planning, construction,
estimated that statewide average per capita flood
operations, and maintenance—from a number
spending from special districts was $31 in 2011,
of sources. One of the main sources is property
but was as high as $77 in the North Coast region
taxes, which in some cases is dedicated specifically
of the state and as low as $0 in the Colorado River
to a special district with flood management
hydrologic region. There was also variability
responsibilities based on local tax formulas, and in
across the regions identified as having the greatest
other cases is allocated within the annual budget
magnitude of population and structures at risk
of a city or county for flood-related activities. Some
(as displayed in Figure 3 on page 8). Residents
local governments also levy special assessments
in the South Coast region paid $26 per capita in
to cover flood management activities. Under the
2011 while residents in the Bay Area paid $39.
State Constitution, as amended by Proposition 218
The special districts from the regions where PPIC
(1996), voters can approve assessments with a
estimated the greatest capital flood improvement
majority rather than a two-thirds vote if the
needs exist—the Sacramento and San Joaquin River
amount paid by each homeowner is directly related
regions—spent $46 and $24 per capita in 2011,
to the benefit his or her property receives. As
respectively.
such, some local flood assessments are structured
with different payment tiers for particular
Federal Government Spending
neighborhoods based on factors such as historic
States and local communities can access federal
flood depths.
funding for certain flood-related activities, but
Other sources of local revenues for flood-
special conditions apply and these funds generally
related activities include general taxes (such as
24 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
are more limited than state funding. As shown future flood-related projects, including along creeks
in Figure 8, annual federal flood management in Merced and Yolo Counties.
expenditures in California have been estimated at Federal Levee Repair Assistance Contingent
between $254 million and $470 million. Upon Meeting Federal Standards and Criteria.
Some Federal Funding for USACE to Conduct The federal PL 84-99 program funds the
Flood Management Projects. Federal funding for rehabilitation and repair of certain levees that are
USACE to conduct a flood management project damaged during flood events. The program fully
is dependent on congressional authorization. funds the rehabilitation and repair of eligible levees
Generally, USACE first undertakes an originally constructed as part of a USACE project
“investigation” of a project to see whether it would (including SPFC levees). Certain nonfederally
merit federal involvement. Then, if Congress constructed levees can participate in the PL 84-99
approves and appropriates funding for the program but require a state or local partner to pay
project, USACE will undertake the project with 20 percent of rehabilitation costs.
a nonfederal partner (usually a local agency) and In order to qualify for this federal funding, a
the state. Often these projects are large, and the levee must meet two key criteria. First, the levee
federal government generally funds 65 percent must maintain “active status” in the program by
to 75 percent of the project cost, with local meeting established national levee standards and
partners and the state sharing the remainder. passing USACE inspections before flood events
(As noted below, portions of state bond funding occur. For example, the levee must not display
have been dedicated to covering some of the local cracking, ruts, erosion, excessive vegetation, or
share of these costs not supported by the federal encroachments (structures or obstructions). (The
government.) Some of these projects are upgrades requirement around encroachments is among the
to prior USACE efforts, such as the construction most problematic for many California levees, given
of a new spillway for Folsom Dam. USACE is structures built over time on top of 100-year old
also in the process of strengthening and raising levees.) Second, USACE must calculate that the
existing levees along the American River. Annual benefits of repairing the levee exceed the costs.
USACE expenditures in California ranged from Under USACE’s current cost-benefit methodology,
$310 million to $970 million between 2000 and meeting this criterion can be hard for some rural
2010. communities to achieve. That is, the protection of
The recent federal Water Infrastructure areas with more sparse population and property
Improvements for the Nation Act, which located behind the levees might not be calculated
authorizes nearly $16 billion in nationwide to generate sufficient economic benefit to offset
spending, was enacted in December 2016. The bill the costs of levee rehabilitation. As such, some of
provided appropriations for USACE to undertake the local agencies maintaining rural levees have
flood-related projects in California, including opted not to pursue active status in the PL 84-99
$880 million for projects along the American and program.
Sacramento Rivers, $780 million for projects in Currently, only 40 percent of SPFC levee miles
West Sacramento, and $70 million for a shoreline (610 miles) maintain active PL 84-99 status and
project along the South San Francisco Bay in Santa qualify for federal rehabilitation funding. These
Clara County. Additionally, the act authorized qualifying levees represent about 85 percent of
USACE to conduct feasibility studies for potential the total population who live behind SPFC levees.
www.lao.ca.gov Legislative Analyst’s Office 25
AN LAO REPORT
Given their higher population and greater number assistance under the Stafford Act four different
of structures, agencies maintaining levees that times in 2017—three times for funding to bolster
protect urban areas have more certainty that they state and local response and recovery efforts to
would meet USACE’s cost-benefit threshold and, damage from storms in January and February
therefore, greater incentive to maintain levees up to 2017—including the damage to the spillway at
federal standards. Within the Delta region, which Oroville Dam—as well as for direct assistance
is largely rural, only about one-third of the 412 to support evacuations of residents living near
levee miles that have historically been part of the Oroville.
PL 84-99 program currently maintain active status. Individuals in Federally Declared Disasters
Some Limited Direct Federal Grants Also May Qualify for Low-Interest Federal Recovery
Available. FEMA offers several hazard mitigation Loans. In certain cases, individuals and businesses
grants to help states and local communities prepare that experience flood damage may be able to access
for and lessen the impacts of disasters, including federal recovery loans through the U.S. Small
floods. These include the Flood Mitigation Business Administration disaster loan program.
Assistance grant program, which annually funds Specifically, individuals may qualify for a
competitive grants for states or local communities low-interest loan of up to $200,000 to help cover
to plan or undertake actions that would reduce flood damage to a primary residence and up to
NFIP claims in the case of a flood. Nationally, $40,000 to repair or replace personal property such
$150 million was available for these grants in 2015 as clothing, cars, and appliances. Businesses may
and $200 million in 2016. As these are competitive apply for a loan of up to $2 million for physical
grants, however, California does not receive damage or economic injury. Such flood recovery
funding every year. For example, the state applied loans, however, typically are available only if the
for $2.8 million to conduct a project in Sonoma President declares a federal disaster. According to
County in 2015 and for $11 million for a project FEMA, federal disaster assistance declarations are
along the Carmel River in Monterey County in issued in fewer than 50 percent of flooding events.
2016, but was not awarded funding for either Moreover, typically the loans must be repaid along
project. with any existing mortgage, although in some
Federal Government Funds Share of State and cases the federal government will help refinance
Local Disaster Assistance Costs in Some Cases. mortgage terms.
In certain cases, as described earlier, the federal
State Government Spending
government provides funding assistance through
the Stafford Act to states and local governments Although flood management is largely a local
that experience flood disasters. Over the past responsibility, the state has a strong interest in
decade, California communities have received avoiding major damage and losses, especially when
nearly $300 million in federal assistance grants state-owned infrastructure, such as highways
for federally declared flood disasters. In addition and buildings, is at risk. The state, therefore,
to or in lieu of funding, the federal government provides some funding to local flood agencies for
may provide direct assistance including food, improvements to levees and other flood-related
personnel, or temporary living arrangements like infrastructure, as well as for nonstructural flood
trailers or hotel vouchers. At the time this report projects and activities. These state programs are
was prepared, the Governor had requested federal funded primarily by state general obligation bonds.
26 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
As shown in Figure 8, DWR/USACE estimated of the $395 million from Proposition 1, all of this
average annual expenditures for flood management funding has been appropriated by the Legislature
by state agencies to be $330 million between 2000 and nearly all of it has already been either
and 2010, whereas PPIC estimated an average of expended or committed for specific projects. These
$574 million annually between 2008 and 2011. bonds will be repaid with interest from the state
Voters Have Authorized $5.1 Billion in State General Fund over the next couple of decades. In
Bonds for Flood Management Over Past Two response to recent winter storms and flooding, in
Decades. Figure 9 summarizes general obligation late February 2017 the Governor requested that the
bonds authorized by voters for flood-related Legislature make an urgency appropriation of the
activities since 2000. Nearly all of this funding was Proposition 1 funds to undertake additional flood-
provided to DWR to use mostly for grants to local related projects. That request was still pending at
agencies, but also for some state-level activities. As the time of this publication.
shown in the figure, the bulk of this funding was Bond Funding Used for Broad Variety of
approved through two 2006 bonds, Propositions 84 Efforts. As shown in Figure 9, the recent bonds
and 1E. These propositions were passed in the have funded a variety of flood management
wake of Hurricane Katrina, when widespread activities and regions. Efforts have focused on
destruction in Louisiana led to increased concerns both structural flood projects (such as levee
about California’s flood risk. With the exception improvements) as well as nonstructural efforts
Figure 9
Recent Bonds Provided $5.1 Billion for Flood Management Activitiesa
(In Millions)
Proposition
13 1E 84 1
Category Types of Activities (2000) (2006) (2006) (2014) Totals
Flood control Evaluate, repair, reconstruct, and replace levees or — $3,000 — — $3,000
projects: structures within SPFC system; develop Central Valley
SPFC Flood Protection Plan; improve emergency response
preparedness at both state and local levels.
Flood control Assist local agencies in paying required nonfederal share of — 500 $180 — 680
projects: federally authorized flood control projects.
federal
Flood control Repair levees, conduct flood risk reduction initiatives, and — — 275 $295 570
projects: make habitat improvements—all in the Delta.
Delta
Flood control Improve levees, conduct feasibility studies, improve — — 275 100 375
projects: emergency response preparedness at both state and local
statewide levels, and support multi-benefit projects.
Flood corridors Conduct projects to restore and preserve natural floodplain $140 290 40 — 470
and bypasses processes, including acquiring easements.
Floodplain Map floodplains and assist local land use planning efforts. — — 30 — 30
planning
Totals $140 $3,790 $800 $395 $5,125
a
Includes only the portion of bond funding dedicated for flood-related activities.
SPFC = State Plan of Flood Control.
www.lao.ca.gov Legislative Analyst’s Office 27
AN LAO REPORT
(such as floodplain restoration and emergency budget on a one-time basis from the General Fund
preparedness). While more than half of the funding to conduct deferred maintenance on levees, in
has focused on improving the SPFC system—due to particular to address pipes or other encroachments
the state’s responsibility for those facilities—funds that might be compromising levee integrity. In
have also supported flood improvements for February 2017, however, the Governor announced
non-SPFC facilities. As shown in the figure, the plans to repurpose at least half of this funding to
funds have supported both projects within and address emergency levee repairs resulting from
outside of the Delta, both federal and nonfederal winter storms.
projects, and activities at both the state and local The state also dedicates some General Fund
levels. Some of the specific projects funded have annually to support disaster response and recovery
been completed, and others are still underway. efforts through the CDAA program. As described
Some General Fund Used for Flood-Related above, CDAA authorizes the Director of OES to
Activities. The state also relies on the General Fund provide financial assistance to support emergency
for some flood-related activities. For example, the response and to repair and restore damaged public
2016-17 Budget Act included more than $50 million infrastructure. CDAA funds are also used to
from the General Fund for staff at DWR to conduct provide state matching funds for federal disaster
its routine flood-related activities, including flood assistance programs. In recent years, the CDAA
forecasting and planning, levee and channel program has had a base budget of $39 million
inspections, and maintenance of the SPFC levees annually from the General Fund. Frequently, the
it manages. The annual budget provides additional process for local governments to tally eligible
General Fund—about $6 million in 2016-17—to disaster-related costs, submit claims, and receive
CVFPB to conduct SPFC permitting and oversight. reimbursement funds through CDAA can take
The state also dedicates annual General Fund to pay years. Between 2004 and 2014, CDAA paid around
the debt service costs for the aforementioned bonds $300 million to local governments for flood and
that fund flood-related activities. Furthermore, severe storm-related disasters.
the state provided $100 million in the 2016-17
ESTIMATED FLOOD MANAGEMENT FUNDING NEEDS
Given the age and condition of most of the the gap between existing spending levels and the
state’s dams, levees, and other flood management expenditures that would be needed to significantly
infrastructure, several studies have estimated reduce the risk of flood damage across the state is
that upgrading the existing system will cost many substantial.
billion dollars above current expenditure levels. Below, we summarize the estimates contained
Developing such estimates is difficult, in part in several flood-related reports for additional
because no comprehensive statewide assessment spending needed beyond current expenditures to
defining specific risk—or the projects that would address the state’s flood risk. In most cases, these
reduce that risk—exists. For example, the state has estimates were developed by aggregating lists of
not defined what projects and level of expenditures identified flood management projects created by
would be necessary to prepare all regions for a local flood management agencies. Moreover, the
100-year or 200-year flood. What is clear is that studies do not specify what level of risk reduction
28 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
these additional expenditures would yield (such others—notably, the Sacramento River, the North
as protection against a 500-year flood). Both the Coast, and possibly also the San Joaquin River
publication dates for the reports and the time regions—other benefits will likely be needed to
frames for their projected costs are somewhat justify these new investments.”
different, which accounts for some of the variance American Society of Civil
in the estimates. Engineers—$28 Billion Statewide Over Ten Years.
DWR and USACE—$52 Billion Statewide. In 2012, this group issued its quadrennial
The 2013 California’s Flood Future report estimated Infrastructure Report Card, and assigned the state’s
costs of $52 billion for 836 flood management levees and flood control infrastructure a “D” grade.
improvements and projects across the state that The authors estimated it would cost an additional
were in the planning or implementation stages. $2.8 billion per year for ten years to bring statewide
This estimate did not include a time frame for levees and flood control systems up to levels it
these expenditures. The report also estimated determined would be safe enough to achieve a
that additional funding of more than $100 billion passing “B” Grade.
might be needed to address flood risk that has not DWR—Around $20 Billion Over 30 Years for
yet been comprehensively assessed and for which SPFC. The Central Valley Flood Protection Plan
specific projects are not yet in the planning or 2017 Update, prepared by DWR for adoption by
implementation stages. the CVFPB—and still in public draft form when
PPIC—$34 Billion Statewide Over 25 Years. we published this report—developed a portfolio
The 2014 report, Paying for Water in California, of prioritized systemwide capital improvements
combined appraisals from various sources to for the SPFC estimated to cost between $13 billion
estimate that it would take $34 billion, or about and $17 billion over 30 years. These include multi-
$1.4 billion annually for 25 years, to implement benefit efforts that would also promote ecosystem
identified flood risk reduction projects to reduce improvements. The plan also calls for additional
flood exposure in California. The report also spending for the SPFC of around $5 billion spread
included a cost-benefit analysis which found that over 30 years for ongoing annual activities such as
“in some regions the avoided costs of private planning, emergency management, and operations
property damage are enough to justify the and maintenance.
added expenditures on flood protection, but in
KEY FLOOD MANAGEMENT
CHALLENGES IN CALIFORNIA
As described throughout this report, flood effective flood management approaches, which are
management is a complicated and expensive summarized in Figure 10 (see next page). These are
undertaking in California, given the state’s size, its issues the Legislature will face as it seeks to develop
extensive and aging infrastructure, the number of additional policies and define budgetary priorities
agencies involved, and the magnitude of its flood that effectively address California’s flood risk.
risk. In this section we highlight some of the key Existing Infrastructure Is Many Years
challenges confronting the state as it pursues more Old. Much of the state’s extensive flood
www.lao.ca.gov Legislative Analyst’s Office 29
AN LAO REPORT
of it is not necessarily
Figure 10
consistent with current
Key Flood Management Challenges in California
statewide goals, scientific
9
Existing Infrastructure Is Many Years Old knowledge, or conditions.
9 For example, narrow
Infrastructure Not Always Designed to Meet Evolving Goals and
or concrete-lined river
Conditions
channels were designed to
9
Flood Management Needs Are Great, but Funding Is Limited and rapidly direct floodwaters
Inconsistent
to the ocean. However,
9
Certain Land Use Decisions Can Increase Flood Risk this design disrupts the
9 natural floodplain and
Involvement of Multiple Agencies Complicates Flood Management
Efforts riverine habitats upon
which native fish depend.
management infrastructure is aged and in need It also precludes some
of improvements. Most of the dams and weirs opportunities to increase water supply because it
in the state are at least 60 years old, and many discharges flood or storm waters before they have
levees—particularly in the Central Valley—were the chance to infiltrate into groundwater basins.
built over 100 years ago and not to modern design Much of the existing system was also
standards. Even well-designed flood infrastructure developed prior to more recent growth in statewide
can become less effective over time—for example, population and current development patterns, so
as reservoirs fill with sediment behind dams it was not designed to protect newly developed
(reducing their capacity) or as earthen levees erode areas. For example, certain segments of Central
under stress from river flows. As infrastructure Valley levees were originally constructed to protect
ages, it faces a greater risk of malfunction and agricultural lands and could occasionally flood
requires increasing maintenance and repair to cropland without serious consequences. Those
remain effectual. Many have raised concerns that same levees now protect populated communities
statewide maintenance practices—and funding— where similar occasional floods would yield
for flood infrastructure have not kept pace with significant damage. Scientific knowledge about
these demands, contributing to the high estimated earthquake fault lines and seismic risks has also
infrastructure costs cited in the previous section. progressed over the past several decades, raising
For example, the state’s Central Valley Flood concerns about how well structures such as dams
Protection Plan 2017 Update asserts that operations meet current seismic engineering standards.
and maintenance activities have been “chronically For example, the San Francisco Public Utilities
underfunded” for the SPFC. The recent damage Commission is in the process of completely
at Oroville Dam highlights both the latent risk replacing the Calaveras Dam (straddling the
inherent in, as well as the state’s critical dependence Calaveras fault line in Alameda and Santa Clara
on, its aging infrastructure. Counties) to address serious seismic concerns, at an
Infrastructure Not Always Designed to estimated cost of $810 million.
Meet Evolving Goals and Conditions. Most of Moreover, the effects of a changing climate
the state’s flood management infrastructure was are placing new demands on the state’s flood
developed in another era, which means much management system. The climate impacts that
30 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
scientists predict California will face include rising raising additional ad valorem property
seas levels, more frequent king tides and storm tax revenue (except for voter-approved
surges, more frequent periods of drought, more bond debt). Additionally, to assess a
precipitation falling as rain rather than snow, and supplemental tax on a property to support
the mountain snowpack melting more rapidly and flood-related activities, Proposition 218
earlier in the season. All of these changes have (1996) can require the community to
the potential to place increased stress on coastal approve the tax by a two-thirds vote, which
development, seawalls, dams, levees, and channels can be difficult to attain. Alternatively, a
that were not necessarily designed to withstand local jurisdiction can levy an assessment
such conditions. for flood-related activities with a lower vote
Flood Management Needs Are Great, but threshold, however, this requires proving
Funding Is Limited and Inconsistent. To meet these that flood projects explicitly benefit each
challenges, additional investments are required property owner in direct proportion to how
to both maintain and upgrade the existing flood much he or she pays. Flood-related projects
management system. As noted earlier, studies often provide diffuse benefits, including to
have estimated associated costs to be in the tens of downstream residents in other tax districts,
billions of dollars. Some of the identified funding making this requirement particularly
needs represent one-time capital projects to upgrade complicated. Generating sufficient tax and
existing infrastructure, while others require assessment revenue is also challenging
ongoing funding for more regular maintenance in many rural areas where the tax base
activities. However, generating funding for flood is relatively small, making it difficult to
management activities can be challenging. Some of spread out the cost of large levee projects.
the key funding challenges include:
• Funding Constraints Can Complicate
• Most State Funding Is From Bonds,
Multi-Benefit Projects. Sometimes
Creating Difficulties for Meeting Ongoing
funding that is available for flood-related
Needs. Bond funds—the primary source
projects is restricted for meeting one
the state has traditionally used for flood
particular outcome, making funding all
management activities—are available
the components of multi-benefit projects
intermittently and therefore not appropriate
difficult. For example, both federal
for sustaining ongoing operations and
funding for USACE projects and local
maintenance costs. This creates challenges
flood assessments typically can only be
both for local agencies that depend on state
used to mitigate flood risk. Such funds
grants for many of their activities, as well
often cannot be used for complementary
as for DWR to identify how to maintain its
efforts that might improve the ecosystem
components of the SPFC.
and provide additional habitat for fish and
wildlife if they are not directly necessary
• Local Funds Hard to Raise. Raising
for flood protection.
additional local funds for flood-related
activities is complicated by certain state
• Need for Flood-Related Investments Fades
constitutional provisions. Proposition 13
From Public Awareness Between Major
(1978) prohibits local governments from
Floods. Public support for flood-related
www.lao.ca.gov Legislative Analyst’s Office 31
AN LAO REPORT
funding typically wanes and waxes public safety. While the state implemented higher
depending on how recently a flood event flood protection standards and some land use
has occurred. During extended periods planning requirements in 2007, they only apply in
without significant flood events, the need certain areas of the Central Valley and are enforced
for investment and protection fades from at the local (not state) level, so are limited in both
public attention even though the risk has scope and effect.
not changed. Generating sufficient public Involvement of Multiple Agencies Complicates
support for passing local assessments or Flood Management Efforts. The overlapping and
statewide bonds can be difficult during fragmented nature of flood-related responsibilities
these years, even though the best time to between various local, federal, and state
maintain and upgrade flood infrastructure governments can complicate flood management
is ahead of the next flood occurring. Flood efforts, particularly for multi-benefit projects.
insurance enrollment rates—the primary Water-related activities can be assigned to
source of recovery funding for individuals various different local agencies within the same
and businesses—also decline during jurisdiction. As such, undertaking a project to
extended flood-free periods, which can capture and retain stormwater flows for future
exacerbate the impacts of damages when water supply, for example, could involve separate
floods do inevitably occur. local government agencies that respectively
have sewer, flood, groundwater, and drinking
Certain Land Use Decisions Can Increase
water responsibilities. Such coordination needs
Flood Risk. Both the state and local governments
can make funding, permitting, overseeing, and
face challenges in determining how to balance
implementing such a project difficult. Similarly,
flood risk with expanding population and
large flood management projects typically can
development. As the state population grows,
involve attaining permits and approvals from
so too does the push to develop into new areas.
multiple federal and state agencies, including state
This development can be both necessary to
and regional water boards, federal and state fish
accommodate additional residents and generate
and wildlife agencies, USACE, and CVFPB. There
additional tax and fee revenue for certain local
are even instances where these agencies impose
jurisdictions. Development in flood-prone areas,
permit requirements that contradict each other—
however, increases the potential for flood damage.
for example, when USACE requires removal of
Even with structural protection such as levees
vegetation or sediment from a levee or channel, but
in place, the residual risk of flooding remains,
those conditions are providing habitat for protected
particularly in historic floodplains. While the
fish and wildlife that the fisheries agencies prohibit
state typically leaves land use decisions up to local
disturbing.
governments, in some cases the state bears financial
In part due to the complication of involving
liability if a flood were to occur. For example, the
multiple agencies, flood management projects
state may be found responsible for damages caused
can take many years to complete. For example,
by failures of SPFC levees, need to repair damage
the recent construction of an auxiliary spillway at
to state-owned infrastructure such as highways
Folsom Dam took roughly 30 years to complete,
or buildings, or face pressure to pay a share of
beginning with flood concerns in 1986, to USACE
local government recovery costs through CDAA.
conducting its first project feasibility study in
Additionally, the state has an interest in protecting
32 Legislative Analyst’s Office www.lao.ca.gov
AN LAO REPORT
1991, to the spillway’s anticipated completion in nearly all of the funding has been committed for
2017. (Additional features of the project, including specific projects, the projects are still underway
raising the dam and updating USACE’s flood- and a significant share remains unspent. (The state
release requirements, have yet to be completed.) typically funds projects on a reimbursement basis
This type of extended implementation timeline after actual costs have been incurred, and therefore
helps explain why ten years after voters approved generally does not sell bonds and provide funding
Propositions 84 and 1E, only about 60 percent to grantees until projects are at or near completion.)
of the bond funding has yet been spent. While
CONCLUSION
Damage from storms in the winter of 2017 at the time this report was prepared, the aged
highlight the state’s flood risk and vulnerability. statewide flood management system has also
After several years of drought, multiple series of performed admirably well, with no catastrophic
wet storms resulted in instances of overflowing failures or widespread damages. The billions of
rivers and creeks, crumbling dam spillways, dollars that local, federal, and state agencies have
breaching levees, mudslides, and collapsing roads invested in flood-related efforts over the past years
and highways. Moreover, scientists predict that have borne benefits. Such efforts remain essential
such alternating extremely dry and extremely wet and ongoing—particularly given the costs and
years will occur more frequently as the result of coordination challenges confronting the state as it
a changing climate, placing additional stress on seeks to better manage its flood risk.
the state’s existing flood infrastructure. However,
www.lao.ca.gov Legislative Analyst’s Office 33
AN LAO REPORT
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AN LAO REPORT
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AN LAO REPORT
LAO Publications
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nonpartisan office that provides fiscal and policy information and advice to the Legislature.
To request publications call (916) 445-4656. This report and others, as well as an e-mail subscription service,
are available on the LAO’s website at www.lao.ca.gov. The LAO is located at 925 L Street, Suite 1000,
Sacramento, CA 95814.
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