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ACTION
AGENDA
CITY COUNCIUREDEVELOPMENT AGENCY
CITY OF HUNTINGTON BEACH
MONDAY, AUGUST 21, 2000
5:00 P.M. - Room B-8
7:00 P.M. - Council Chamber
Civic Center, 2000 Main Street
Huntington Beach, California 92648
5:00 P.M. - Room B-8
Call Citv Council/Redevelopment Agency Meeting To Order
Roll Call Julien, Sullivan, Harman, Garofalo, Green, Dettloff, Bauer
[Present- Julien 5:03 p.m.; Garofalo absent]
[City Clerk announced revised page 2 - (rewording of closed session
item)]
Public Comments Regarding Study Session & Closed Session Agenda Items
[None]
(City Council/Redevelopment Agency) Study Session— Flood Management Plan —
Identification of Potential Local Flood Hazards and Recommendations for Establishment of
Goals for the Mitigation and/or Reduction of Flood Hazards (550.50)
Communication from the Planning Department titled Flood Management Plan— City of Huntington
Beach dated August 2000 which includes identification of problems associated with those hazards,
and goals to establish reduction and/or mitigation of the flood hazards.
[Susan Pierce, Senior Planner presented staff report. City
Administrator to return with report regarding City's study and policy
recommendations on EIR (Environmental Impact Report) relative to
Council's position on the Wintersburg Channel re: balance of flood
control protection vs. damage to restored Bolsa.Chica wetlands.]
COMPUTER INTERNET ACCESS TO CITY COUNCIUREDEVELOPMENT AGENCYAGENDAS
IS AVAILABLE PRIOR TO CITY COUNCIL MEETINGS
http.-Ilwww.ci.huntington-beach.ca.us
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TABLE OF CONTENTS
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Section Page
1.0 PURPOSE AND INTRODUCTION 1
1.1 Purpose 1
1.2 Introduction 1
1.2.1 Floodplain Created 1
1.2.2 Flood Hazard Study 1
1.2.3 National Flood Insurance Program 2
1.2.4 Community Rating System 2
1.2.5 City Council Direction 3
2.0 FLOOD MANAGEMENT PLAN COMMITTEE - 4
2.1 Committee Established 4
2.2 Committee Membership 4
2.3 Committee Meetings 4
3.0 COMMUNITY DESCRIPTION 6
4.0 HAZARDS 7
4.1 Weather Related Flooding 7
4.1.1 Tropical Storms 8
4.1.2 Heavy Rain 8
4.1.3 High Water Table/Wetlands 8
4.1.4 Tornados 8
4.2. Flood Control 9
4.2.1 Santa Ana River 9
4.2.2 Dam Failure 9
4.2.3 Flood Control Channels 11
4.2.4 Pump Stations 12
4.3 Pacific Ocean Activity 13
4.3.1 High Tides 13
4.3.2 High Surf 14
4.3.3 Beach/Bluff Erosion 14
4.3.4 Tsunami 14
4.4 Accidents 14
4.4.1 Reservoirs 14
4.4.2 Water main/fire Hydrant Breaks 14
4.5 Other Geologic Hazards 15
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5.0 HAZARD RELATED IMPACTS 16
5.1 Heavy Rain/Tropical Storms 16
5.1.1 Repetitive Flooding Areas 20
5.1.2 Repetivie Loss Properties 26
5.1.3 Santa Ana River History 27
5.3 High Tides and High Surf 28
5.4 Tornados 28
5.5 Buildings 29
5.5.1 Public Buildings 29
5.5.2 Historic/Local Landmarks 29
5.5.3 Critical Facilities 30
5.5.4 Hazardous Chemical Facilities 30
5.6 Wetlands, Undeveloped Properties, and Open Space Areas 30
5.7 Protective Measures in Effect or Under Construction 31
5.7.1 Santa Ana River Mainstem Project 31
5.7.2 'County Projects - _. 31
5.7.3 Local Projects 34
5.7.4 Flood Insurance 36
5.7.5 Seawalls 37
5.7.6 Warning Systems and Evacuation 37
5.7.7 Zoning and Construction Regulations 38
5.7.8 Beach/Wetland Protection 38
5.8 Fiscal Impact 38
5.8.1 Funding 38
5.8.2 Flood Damage Expenses 39
5.8.3 Flood Management/Prevention Expenses 40
5.8.4 Financial Assistance 41
6.0 GOALS 42
7.0 POSSIBLE ACTIVITIES 43
8.0 RECOMMENDATION 45
8.1 Goal EH4— Flooding 45
8.2 Goal U3 — Storm Drainage 47
8.3 Goal EH5—Tsunami 49
8.4 Goal ERC2 — Biological Resources 49
8.5 Goal EH2 — Erosion 50
8.6 Goal LU14 —Open Space 50
8.7 Goal HCR1 — Historical Resources 51
8.8 Recommended Activities Matrix 52
9.0 IMPLEMENTATION 57
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EXHIBITS
Exhibit No. Description Following Page
1 Vicinity Map 6
2 Ranges of Elevations in Huntington Beach 6
3 Near Surface Water 8
4 Geographic Features 8
5 Prado Dam Indunation Map 10
6 Regional Drainage System 11
7 Regional Drainage Map 11
8 Flood Control Channels and Pump Stations 11
9 Moderate Tsunami Run-Up Area 14
10 Newport-Inglewood Fault Zone 15
11 Subsidence Areas 15
12 Potentially Unstable Slope Areas 15
13 Liquefaction Potential 15
14 Methane Overlay Districts 15
15 Rainfall Data Chart 16
16 Local Flooding Map 20
17 Santa Ana River and Residual Floodplains 36
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1.0 PURPOSE AND INTRODUCTION
1.1 PURPOSE
The purpose of this document is to identify potential flood hazards and methods
to reduce or mitigate flood damage. Adoption of the Flood Management Plan
(Plan) will assist local, state, and federal flood mitigation and planning efforts. It
will also ensure that flood insurance premium reductions continue to be available
to Huntington Beach property owners and tenants.
1.2 INTRODUCTION
1.2.1 Floodplain Created
In 1968 Congress created the National Flood Insurance Program (NFIP) in
response to the rising cost of taxpayer disaster relief for flood victims and the
increasing amount of damage caused by floods nationwide. This program was
administered by the Federal Insurance Administration (FIA), a part of the
Department of Housing and Urban Development. It led to the mapping of areas
susceptible to 100-year flooding from known rivers, creeks, and other large
bodies of water. The 100-year floodplain is also referred to as a special flood
hazard area (SFHA).
In 1971 the US Army Corps of Engineers delineated the limits of such a flooding
in Huntington Beach. This map was based on the historical data and
hydrological studies for areas within the Santa Ana River Floodplain that includes
Huntington Beach.
During President Carter's administration, the Federal Emergency Management
Agency (FEMA) was created and FIA transferred to FEMA. In the early 1980s,
the City petitioned FIA to reconsider the floodplain as delineated on the flood
map for Huntington Beach. As a result, over 80 residential neighborhoods were
removed from the floodplain by the issuance of multiple Letters of Map
Amendment based on the actual site elevation and lowest floor elevation of the
various structures in relation to the established base flood elevation. Since then
the flood map has been revised several times based on other hydrological data
and to reflect protective measures in place. It continues to depict over 50
percent of the city within the 100-year floodplain.
1.2.2 Flood Hazard Study
During April 1974 the City of Huntington Beach Planning Department prepared a
Flood Hazard Study as a background report for the City's combined Seismic-
Safety Element of the General Plan. The intent of that report was to compile
what was known at that time about the actual flood potential in the City, to
identify existing control measures, to examine land use hazards, and to
1
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investigate hazard abatement alternatives. Floodwater from the Santa Ana River
was the only source of flooding considered in the report. Discussion of the
control measures for the river and the flood control drainage systems that
traversed the city was minimal. This information was incorporated into the
General Plan that was adopted in 1976. A comprehensive General Plan update
occurred in 1996. It includes the Hazards Element that addresses local hazards
including tsunamis and flooding and identifies goals and policies to minimize
these hazards.
1.2.3 National Flood Insurance Program
Flood insurance is available to residents and property owners of communities
that adopt and enforce floodplain management regulations required by FEMA.
The City of Huntington Beach entered the flood program on February 16, 1983,
with the adoption of the City's first floodplain development regulations. These
regulations enforce the requirements of FEMA for development of property
located within the SFHA. The basic objective of the floodplain regulations is to
ensure new buildings will be protected from flood damage and that development
will not aggravate existing flooding conditions. Much of the City lies within the
SHFA. Huntington Beach is one of 19,000 communities nationwide participating
in the National Flood Insurance Program.
1.2.4 Community Rating System
In 1994, the City Council directed staff to apply for participation in the NFIP
Community Rating System (CRS) which is a special program used by FEMA to
allow reductions in flood insurance premiums. CRS contains many activities that
exceed FEMA requirements for implementation to minimize flood damage.
These include activities for public awareness as well as various methods and
practices to protect property. Communities that can demonstrate that they
implement activities that exceed the minimum requirements are awarded credit
points. The credit points are then translated into classes (1-10, with 1 being the
highest class). A minimum of 500 points is required for participation in the CRS
program, which results in a class 9 rating. Each rating allows reduction in flood
-insurance premiums. The City received 1,112 points and initially a class 9 rating
effective October 1995 with a Class 8 rating effective October 1, 1996. Class 8
communities are allowed a ten-percent reduction in flood insurance premiums.
In 1999, prior to the five-year recertification of the CRS application, the City was
notified that there are 15 repetitive loss properties in the City. As part of the CRS
program, communities with ten or more properties that have received financial
assistance from NFIP two or more times within a ten year period must prepare
and adopt a floodplain management plan. Subsequently, the City submitted
documentation supporting that protective measures had been implemented to
reduce flood damage to some of the properties. FEMA ponfirmed this
information and revised the repetitive loss properties to seven. Although no
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longer a mandatory requirement to adopt a flood management plan, Planning
staff believes that adoption of a flood management plan is beneficial to the
community since many areas within the City are subjected repetitive flooding.
This document will provide essential information and formulates a strategy to
reduce flood damage in the future.
At the conclusion of the five-year recertification, the City received 1,551 points
and a Class 7 rating effective October 2006. Properties located in SFHA zones
A (with no base flood elevation), AE, AO, AH, V, and VE will receive 15 percent
reduction in flood insurance premiums. Properties located in other flood zones,
i.e., X and A99, will continue to receive five-percent reduction for the rate
applicable to these preferred risk flood zones.
1.2.5 City Council Direction
At the November 1, 1999, City Council meeting, the City Council directed the
Planning Director to prepare a Flood Management Plan for its adoption. This
Plan will supplement the previously prepared documents that address flooding.
During the FMP process, FEMA advised staff that the FMP did not need to
comply with the mandatory completion time because eight of the 15
repetitive loss properties would benefit from recent improvements to
County flood control channels. Staff believed that the FMP is important to
the community and continued the process.
3
2.0 FLOOD MANAGEMENT PLAN COMMITTEE
2.1 COMMITTEE ESTABLISHED
A Flood Management Plan Committee was created consisting of a representative
each from the Departments of Planning, Building and Safety, Fire, Public Works
— Engineering, Public Works — Maintenance, and Administration — Public
Information. Staff invited seven members of the community who live within areas
subject to repetitive flooding to join the committee.
2.2 COMMITTEE MEMBERSHIP
The Committee members are:
Valerie Curry Resident
Chris Gray Public Works Department> Maintenance
Jim Hicks Resident
Jack Kintz Resident
Steve Krieger Public Works Department— Engineering
Glorria Morrison Fire Department
Khanh Nguyen Building and Safety Department
Bob O'Donnell Resident
Tom Pejovich Resident
Susan Pierce Planning Department (Chairperson)
John Tarvin Public Works Department— Maintenance
Walt White Resident
Cecil Wright Resident
The following staff members provided assistance to the Committee:
Dave Dominguez Community Services Department
Joe Mangiameli Public Works Department - GIS
2.3 COMMITTEE MEETINGS
The first meeting of the committee was held on November 4, 1999. At that
meeting the committee determined that the focus of the Plan would be to address
flooding on a citywide basis and to consider all sources of flooding.
Biweekly meetings continued to define hazards, identify problems related to the
hazards, set goals to reduce flood hazard damage, identify activities to attain the
goals, and to draft an action plan. A representative from the County of Orange
Flood Program met with the committee to discuss known problems with the
County's flood control channels and mitigation efforts completed and proposed.
Input was solicited from various agencies and adjacent cities. Past flood
4
damage/problem information was requested from residents of repetitive loss
properties. Results of the inquiries and agencies' input were incorporated into
committee discussions and the Plan.
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3.0 COMMUNITY DESCRIPTION
Huntington Beach, California, is located at the northwestern edge of Orange
County. It is bordered by Westminster to the north, Fountain Valley to the
northeast, the Pacific Ocean to the west and southwest, Seal Beach to the
northwest, and the Santa Ana River to the east. Costa Mesa and Newport Beach
lie east of the Santa Ana River. The boundaries of the city are irregularly shaped
with a base of approximately nine miles along the coastline. The area within the
city boundary is 27.7 square miles. (See Exhibit 1.) Population estimates reveal
approximately 199,326 persons reside in Huntington Beach.
Huntington Beach has a mean annual rainfall of 12 inches, and a mean monthly
temperature of approximately 62°F. The topography, which is primarily flat,
varies from below sea level to over 100 feet above sea level. There are two
mesa areas that disrupt the steady slope of the land toward the ocean. Exhibit 2
depicts elevations within the City. A considerable portion of the-community is
less than 10 feet above sea level and properties located in the eastern portion
are lower than the Santa Ana River. Several areas of the city are also lower than
the top of the adjacent County flood control channel.
Three major highways traverse the City to provide both regional and inter-
regional access. Pacific Coast Highway (State Highway 1) parallels the shore
and provides regional access from Newport Beach to Seal Beach. State
Highway 39 (Beach Boulevard) runs in a north-south direction near the center of
the city. It provides access from Orange and Los Angeles Counties to the coast.
Interstate 405 (San Diego Freeway) at the northern edge of the city provides
regional access to coastal cities in both Orange and Los Angeles Counties.
6
4.0 HAZARDS
Geologic and seismic hazards have been identified in the General Plan. These
hazards include shallow water depth, faults, liquefaction, tsunami and seiche,
subsidence, methane, and flooding. Flooding can be the result of a variety of
causes or hazards. The Committee identified the following hazards for inclusion
in the Flood Management Plan:
Bluff erosion Pump stations
Dam failure Reservoirs
Earthquake faults Santa Ana River
Flood control channels Subsidence
Heavy rain Tornados
High ground water table Tropical storms
High surf Tsunami
High tides Unstable slopes .
Liquefaction Water main breaks
Methane
These hazards are grouped into five general categories for discussion. They are:
♦ Weather related flooding from heavy rains, tropical storms, and tornados
♦ Flood control (Santa Ana River, dam failure, flood control channels, pump
stations)
♦ Pacific Ocean activity including high surf, high tide, tsunami, beach/bluff
erosion
♦ Accidents such as reservoir leaks and water main breaks _
♦ Geologic hazards including earthquake, subsidence, liquefaction,
methane, unstable slopes
4.1 WEATHER RELATED FLOODING
Huntington Beach weather conditions are consistent with coastal southern
California. During the winter months an average of 12 inches of rainfall occurs in
this semi-arid region. Summer months are warm and dry. A threat of severe
winter storms is greatest during December to March. The threat from tropical
storms is greatest August through October as a result of hurricanes from Mexico.
The southwest facing beach of Huntington Beach can cause surf and wave
impact from both winter and summer storms. Heavy rains combined with high
tide and rough surf create an increased potential for flooding. High tides often
prevent the Santa Ana River flow into the ocean and result in flooding in the
south end of the city.
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4.1.1 Tropical Storms
The City has experienced tropical storms related to an El Nino condition. An El
Nino is an oceanic and atmospheric phenomenon in the Pacific Ocean that
causes climatic disturbances: The disturbances occur when the ocean
temperatures in the southeastern portion of the Pacific are unusually high. Air
pressure is very low over the warm water. This causes the moist air to rise,
causing clouds and heavy rainfall. As the trade winds blow from east to west, the
unusually warm weather and tropical rain storms hit southern California including
Huntington Beach.
4.1.2 Heavy Rain
Several areas in the City have repeatedly experienced local flooding due to
heavy rain. Many of these areas are adjacent to pump stations and/or flood
control channels that are not capable of containing the floodwaters. Several
areas are low lying areas where proper drainage is not provided. -And, in some
areas, there are no catch basins to direct water flow to a storm drainage system.
Because the city is relatively flat, there is not enough decline in elevation to allow
water flow by gravity to the ocean and pumps must be used or provided to insure
timely drainage.
During periods of heavy rains, water fills the storm drainage system to capacity.
Nearby pump stations are unable to pump the accumulated rainwater into the
substandard flood control channels. Drainage problems occur as the excess
water begins to fill streets and accumulates on adjacent properties.
4.1.3 High Water Table/Wetlands
A large portion of the southeastern area of the city has a high water table. (See
Exhibit 6.) When the city experiences heavy rains, the land is incapable of
absorbing any additional water and flooding may occur. Some of the high water
table areas have been classified as wetlands. Wetlands may be found on the
inland side of Pacific Coast Highway between the Santa Ana River and Beach
Boulevard and in the Bolsa Chica area inland of Pacific Coast Highway between
Warner Avenue and Seapoint Street. (See Exhibit 4.) The Talbert Marsh
wetland and the Bolsa Chica receive local drainage waters and tidal influx from
the Pacific Ocean. These wetlands provide a holding area for localized flooding
and a habitat for wildlife.
4.1.4 Tornados
A tornado is a violent whirling wind accompanied by a funnel-shaped cloud
extending down from a cumulonimbus cloud. The vortex may be several
hundred yards wide whirling destructively at speeds up to 300 miles per hour.
The narrowest portion is where the funnel touches the ground. The funnel is
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visible by the dust it accumulates and the condensation of water in the center.
Tornados develop in low-pressure areas of high winds and usually spin
counterclockwise. Damage occurs as the tornado funnel moves over and
touches land. Structures may explode when they are not sufficiently ventilated to
adjust rapidly to the change in air pressure. Rain and hail often accompany
tornados. Although tornados are rare in southern California, three tornados have
damaged properties in the City.
4.2 FLOOD CONTROL
4.2.1 Santa Ana River
Huntington Beach lies within the Santa Ana River floodplain. The Santa Ana
River begins near the Mt. San Gorgonio summit in the San Bernardino Mountains
at an elevation of over 8,000 feet. Its course drains over 90 miles through both
the San Bernardino and Santa Ana ranges; 27 miles of the river course flows
through Orange County to the Pacific Ocean. The Santa Ana River drainage
basin covers 2,450 square miles and is the largest basin in southern California.
Many hundreds of years ago the Santa Ana River flowed through the area now
known as the Bolsa Chica wetlands. Later it abandoned its course and
established a new course in the Santa Ana Gap. Alterations to the river's path
created the cliffs of Upper Newport Bay and deposited sands that formed the
Newport-Balboa Peninsula. The Santa Ana River is the largest river in Southern
California and the flow from the Prado Dam reservoir through Orange County
was perennial. Since construction of the Prado Dam in Riverside County,
increasing upstream usage, and development in adjacent counties, the river is
very low most of the year. Most of the water is used for irrigation and recharging
the underground water basin. Little continues to flow to the ocean. With the
completion of the Prado Dam and channelization of the river, water flow was
contained in 1940. At that time most of the river followed its natural course while
the remaining portion including that within the City was a levee, sand bottom
channel.
4.2.2 Dam Failure
There are two flood control dams that control flood flow of the Santa Ana River.
The Seven Oaks Dam is located on the river in the upper Santa Canyon about
eight miles northeast of the City of Redlands, in San Bernardino County. This
dam was completed in 1999. The Prado Dam is about 40 miles downstream of
the Seven Oaks Dam. Approximately 47 billion gallons (145,600 acre-feet) of
water can be stored in the Seven Oaks reservoir and 61 billion gallons (187,600
acre-feet) in the Prado reservoir.
During a flood, the Seven Oaks Dam will store water destined for the Prado Dam
for as long as the reservoir at Prado Dam is rising. When the water surface of
9
Prado Dam reservoir is less than the buffer pool, water conservation releases are
made. Water conservation releases are then made in coordination with the
Orange County Water District based on the capacity of the groundwater recharge
facilities and agreements with other agencies. Flood control releases occur
when the water surface in the reservoir exceeds the buffer pool. Releases are
increased to match inflow from upstream (5,000 cubic feet per second). The
objective of the flood control operation is to drain the reservoir pools as quickly
as possible without exceeding the capacity of the channel downstream. When
the water surface elevation in the Prado Dam reservoir exceeds 543 feet,
uncontrolled releases from the spillway occur.
In the event of Prado Dam failure, floodwaters would flow through the Santa Ana
Canyon on its way to the Pacific Ocean. The flood would range from about 3,000
feet wide in the canyon to over 15 miles wide downstream at the Santa Ana
Freeway (Interstate 5). The flooding would impact over one million people and
110,000 acres. Within 8-10 hours, the intersection of Beach Boulevard and
Edinger Avenue would experience severe flooding. The peak elevation would be
32 ft. with 7-ft. average over the river's bank depth. The greatest flooding would
occur in the area between the Bolsa Chica Mesa and the Newport Beach Mesa
where flood depths can vary from one to nine feet. (See Exhibit 5.)
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4.2.3 Flood Control Channels
A large amount of water from other parts of Orange County flow through
Huntington Beach on the way to the ocean. These regional water flows are
carried through flood control channels owned and operated by the County of
Orange. In addition to these channels, the City of Huntington Beach maintains
flood control channels to drain local floodwaters. (See Exhibits 6, 7, 8, and 16.)
4.2.3.1 County Channels
The existing County channels were constructed in the early 1960s to meet 65
percent of the 25-year rainfall (flood) level, the design criterion at that time.
These channels were constructed with a restrictive bottom, which reduces the
amount of water that could be carried. The restrictive bottoms allow the County
to slow the runoff water flow rate while still allowing the system to remove runoff
water. At that time the County believed that the restrictive design could be
removed or the channel bottom smoothed in the future to increase-the efficiency
of the channel capacity. Today's design standard is for 100 percent of the
100-year flood. (A 100-year flood is a flood event that has a one percent chance
of being equaled or exceed in any year.)
Bartlett Park, located north of Adams Avenue and east of Beach Boulevard, is an
emergency retention basin. The County has an easement on this property to
retain water that will eventually be pumped by the County's pump station, that is
located on the south side of Adams Avenue, downstream into the Huntington
Beach (D01) channel and eventually into the Pacific Ocean. The basin was
constructed approximately ten years ago.
4.2.3.2 City Channels
The City of Huntington Beach maintains four storm drain channels throughout the
city. These channels were designed to accommodate up to 60 percent of a 25--
year flood event. Ground level channels exacerbate flooding because the
amount of water that can be pumped into these channels is less than a channel
constructed below grade. Localized flooding then occurs because the pump
stations are unable to pump additional water into the channel without the
possibility of overflow onto adjacent properties.
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REGIONAL DRAINAGE SYSTEM
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Orange County Flood Control District Channels that pass through Huntington Beach
Bolsa Chica Channel (CO2)with tributaries Anaheim-Barber City Channel (CO3) &
Westminster Channel (C04)
1. Drains portions of Huntington Beach, Westminster, Los Alamitos, Cypress,
Garden Grove, Stanton and Anaheim.
2. Drainage passes through Anaheim Bay and the Seal Beach National Wildlife
Refuge before emptying into the Pacific Ocean at Seal Beach..
East Garden Grove-Wintersburg Channel(C05)with tributary Ocean View Channel
(C06)
1. Drains portions of Huntington Beach, Westminister,Fountain Valley, Santa
Ana and Garden Grove.
2. Drainage passes through the Bolsa Chica Biological Reserve before entering
Huntington Harbor, Anaheim Bay and the Seal Beach National Wildlife
Refuge before emptying into the Pacific Ocean at Seal Beach.
Sunset Channel (CO7)
1. Drains a small portion of west Huntington Beach.
2. -Drainage passes through Huntington Harbor,Anaheim Bay and the Seal
Beach National Wildlife Refuge before emptying into the Pacific Ocean at
Seal Beach.
Talbert Channel (D02)with tributaries Huntington Beach Channel (DO1) &Fountain
Valley Channel (D05)
1. Drains portions of south Huntington Beach and Fountain Valley.
2. Drainage passes through the Talbert Marsh before emptying into the Pacific
Ocean just west of the Santa Ana River.
EXHIBIT 6
(map on Exhibit 7)
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4.2.4 Pump Stations
There are 16 pump stations within the City that are an important part of the
drainage system. They are used to pump water flow from low lying public and
private property to higher channel elevations for eventual flow to the ocean.
Pump stations may also pump water into flood.control channels from storm
drains that do not flow directly to the ocean. One of the pump stations is owned
and operated by the County of Orange; it has six pumps. The remaining stations
are owned and operated by the Huntington Beach Public Works Department.
Depending on the size of the tributary area a station can have two to eight
pumps. Currently there are 47 pumps in the 15 city-owned stations.
Every station is setup differently but their functionality remains the same. The
number of operating pumps in a'station is correlated to the height of the water
within the station. Once a predetermined elevation has been breached the first
pump is activated. If the water level continues to rise, additional pumps are
activated. Each pump operates in unison trying to keep the water level at the
predetermined elevation. The pumps continue to run until the water level
recedes.-'-Once this happens the pumps shut down in the opposite order than
they start. Pump station locations are shown on Exhibits 8 and 16. Presently all
of the City's pump stations are operating within their current design capacities
and are considered deficient by current standards.
12
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The County of Orange has informed the City that installation of additional pumps
or pump stations will not improve the drainage problems that frequently exist
during periods of heavy rains until its channels are improved. The main problem
lies with the incapacity of the channel system to carry any additional water that
may be pumped. Capacity in a.channel is dependent on its height and width
and on the design of the channel(s) downstream. When a channel does not
comply with the minimum FEMA 100-year capacity, any additional water pumped
into a'channel may breach the channel banks, cause channel failure, and/or
create flooding problems for adjacent properties. - - - - - - ---- --
4.,3 PACIFIC OCEAN ACTIVITY
4.3.1 High Tides
Tides are the periodic rise and fall of all ocean waters resulting from the
gravitational attraction of the moon and the sun upon the water and upon the
earth. Because the moon is much closer to the earth than the sun, it is the
principal cause of tides. The location of the moon over the.earth creates a:
powerful pull on the water, which then.rises above its normal level. High and low
waters alternate in a.continuous cycle with two high waters and two low waters
every lunar day.-The average lunar day is 24 hours,-50 minutes, and 28 -
seconds. Two successive high,or low.waters are generally the same height.
13
4.3.2 High Surf
High surf occurs when wind from storms at sea forces the water level and wave
action toward the shore. Typical surf in Huntington Beach is two to four feet, and
waves up to 25 feet have occurred during heavy storms.
4.3.3 Beach/bluff erosion
Beach and bluff erosion is a result of the high tides and high surf. Continual
erosion could impact highway and beach access and possible bluff failure.
4.3.4 Tsunami
A tsunami is an oceanographic event with gigantic waves that strike the
surrounding shore with tremendous force. Underground earthquakes, midocean
volcanic eruptions, and serious atmospheric disturbances cause the waves.
A tsunami threat to the City of Huntington Beach is considered to be low to
moderate. Since the city has southwest facing beaches, they are vulnerable to
south and west tidal surges or tsunamis. Predicted wave heights vary from 4.0 ft.
to 9.2 ft. for 100-year occurrences and from 6.8 ft. to 16.0 ft. for 500-year
occurrences. Areas subject to tsunami runup are depicted on Exhibit 9.
4.4 ACCIDENTS
4.4.1 Reservoirs
A total of 49.5 million gallons of water can be stored in the city. There are two
reservoirs located in the city and a new one under construction. The Overmeyer
Reservoir consists of two storage areas, 21.5 million gallons and 3 million
gallons. This reservoir is located at the water warehouse/maintenance facility at
Huntington Street and Garfield Avenue. A second water reservoir, Peck
Reservoir, is located at Springdale Street and Skylab Road. This reservoir
contains 16 million gallons of water. These reservoirs are underground and no
flooding could occur if the reservoirs fail; no properties would be affected.
A new reservoir, Edwards Hill, which is under construction, is located west of
Edwards Street, north of Garfield. This reservoir is mostly underground, and will
have a 25 million gallon capacity. Any water leakage would drain westerly into
the Bolsa Chica wetlands.
4.4.2 Water main/fire hydrant breaks
Accidents to water mains or fire hydrants may cause temporary localized
flooding. Water main damage could occur anywhere within the city_because of
age, pipe corrosion or sudden changes in pressures. Fire Department and
14
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would be short term flooding.
4.5 OTHER GEOLOGIC HAZARDS
Some geologic hazards may create or be affected by flooding. These include
earthquake faults, subsidence, and unstable slopes. A series of'earthquake
faults traverse the city. An earthquake could rupture water lines, damage bridges
and flood control channels, or create crevices that would allow water
accumulation. Earthquake tremors can cause soils with liquefaction potential to
loose strength and liquefy. This may result in ground settlement, which
sometimes causes buildings to sink or tip over, or shallow landslide conditions.
Oil, water, and gas extraction in the city has created areas where subsidence
may occur. This extraction reduces the force on the ground surface allowing
land and/or structures to collapse and become more tightly packed. Sea level
rise affects coastal flooding as land subsidence occurs. When-the two are
combined there is threat of serious future flood damage to the coastal areas.
Unstable slopes may fail during heavy rains and may create mudflows.
These hazards plus methane, which is found in areas where oil extraction has
occurred, are shown on Exhibits 10 - 14 and are addressed in the Hazard
Element of the General Plan. Methane does not create or impact flood damage
but is a known hazard to the community. It is included for information only.
15
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LIQUEFACTION POTENTIAL 05 ID z --
EH-7
CITY OF HUNTINGTON BEACH GENERAL PLAN `
EXHIBIT 13
....... ........ ........
....... .... .7I
RIM
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METHANE OVERLAY DISTRICTS -10
CITY OF HUNTINGTON BEACH GENERAL PLAN iEH
5.0 HAZARD RELATEDIMPACTS
5.1. HEAVY RAIN/TROPICAL STORMS
As previously mentioned the mean average rainfall for Huntington Beach is 12
inches. Rainfall records measured at the Meadowlark Golf Course area for the
past 20 fiscal years are shown on Exhibit 15. Periods of heavy rainfall over 20
inches are:
1977/1978 26 inches
1982/1983 22.5 inches
1992/1993 22.10 inches
1994/1995 21.8 inches
1997/1998 27.5 inches
A brief summary of flooding events reported in local newspapers follows:
➢ Following a heat wave in 1939 with record high temperature of 119
degrees on September 21, a tropical rainstorm with heavy winds walloped
the coast, drowning dozens of people, sinking boats, and flooding homes.
A 300-foot section of the Huntington Beach pier was torn out.
➢ During the February 1969 storm, Huntington Beach storm drains and
flood control channels were unable to handle the extreme water flow and
nearly all of the lowlands were covered with water.
➢ A series of storms in 1983 lashed Orange County's coast causing heavy
damage to the Huntington Beach pier and flooding many homes. As a
result, more than 900 homes were inundated with water. Damage was
$25 million. (The City's Emergency Operations Center [EOC] was
activated for three days.)
16
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76/77
77/78
78/79
79/80
80/81
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82/83
83/84
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85/86
86/87
87/88
CA88/89
w
89/90
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90/91
9v92
92/93
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95/96
96/97
97/98
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Huntington Beach Pier- 1983
V
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South of Adams Avenue and North New Britain - 1983
17
➢ In January 1988, a powerful storm whipped up to 20-foot waves and
dropped 250 feet of the pier into the ocean. The high wave heights were
combined with a high tide of seven feet.
RR
IN
_N�Um
5-
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k.
End of Pier— 1988
➢ Huntington Beach received 4.5 inches of water on January 4, 1995,
causing flooding to several areas of the city. Streets were flooded, cars
were stalled and people were stranded by water surrounding their homes.
Marine Safety was called to evacuate eight neighborhoods where people ---
could not safely leave their homes due to waist-high water. (EOC was
activated.)
18
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Adams Avenue and Lexington Lane
➢ On December 6, 1997, Huntington Beach experienced two days of hard
rains causing 400 residents of two flooded mobilehome parks to be
evacuated by rubber rafts. The flash flood raised water in the mobilehome
parks 2-3 feet within approximately 30 minutes. More than a dozen
homes were flooded and all residents were evacuated due to waist-high
water. The heavy rains were related to the El Nino weather pattern. Other
19
events that related to this storm included flooded streets, high surf, raging
storm drains, and significant erosion at the city beach. The high surf
undermined restroom buildings at the city beach. (City's Emergency
Operation Center [EOC] was activated.)
➢ EOC was activated twice during the first week of February 1998 as a
result of continuing storms with increased intensity due to an El Nino
condition. The intensity of rain caused closure of numerous streets.
throughout the City. A sudden downpour, preceded by constant rainfall
caused a flash flood down Brookhurst Street, between Garfield and
Adams Avenues. The water entered the Del Mar Mobilehome Park,
raising the water levels in parts of the park up to 2-3 feet within 30
minutes. Twenty-five residents were evacuated to the park's recreation
room and remained there until Fire and Public Works crews managed to
pump and drain out most of the water. Approximately 500 sandbags were
used to barricade the park's entry. None of the mobilehomes sustained
flood damage.
➢ A two mile stretch of Pacific Coast Highway was closed at Bolsa Chica
State Beach due to more than 2-inches of rain and 10-foot high waves
during February 2000. Power outages were experienced in several areas
of the City.
5.1.1 Repetitive Flooding Areas
Areas that have experienced local flooding within the past 20 years are depicted
in Exhibit 16. A description of flooding problems in these areas is identified in the
following paragraphs. Approximate water depths are measured from the flowline
of adjacent streets. Each of the areas has common problems: inadequate
drainage, properties lower than the nearby flood control channel, or lower than
the nearest arterial street. During normal rains as well as heavy rains, many of
the residential neighborhoods in the City experience flooding. This is a result of
a common development design in the 1960-1970s that created neighborhoods
below the level of the adjacent arterial. In these areas it is common to
experience curb-to-curb flooding. Many properties that have been graded in a
manner that allows water flow toward the house/structure. Flooding occurs
where tree roots have raised sidewalks and cracked curbs and gutters prevent
natural drainage to the storm drain.
20
s9ti
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00
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3
McFADDEN AVE.
EDINGER I AVE 24
- 1 5 ��.. 2
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= c� - 6
c WARNER $ AVE.
-- -- c 0
SLATER AVE.
405
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i
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31 9� 3 N
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16
• INDLANAPOUS AVE Y
14 2 m
61 8 1 ATLMTA AVE
LEGEND
-- — CITY CHANNELS 17
----- — CITY BOUNDARY m I AVE.
l
— CITY PUMP STATIONS °
—�� — COUNTY CHANNELS �'cB^NMN
• — COUNTY PUMP STATION o� 5
® INDICATES AREAS OF
LOCAL FLOODING
(1970-1999)
— APPROXIMATE LOCATION
OF CRITICAL FLOOD AREA
• .� CITY OF HUNTINGTON BEACH
DEPARTMENT OF PUBLIC WORKS
LOCAL FLOODING MAP INCLUDING
DRAINAGE CHANNELS & PUMP STATIONS
NWEMBER 1999
EXHIBIT 16
n 3
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4�
5.1.1.1 Area 1 - Heavy rain combined,with extreme high tides (6.8 feet or
greater) impair the water to drain properly from the area near Saybrook Lane
south of Edinger Avenue. Water depth is estimated to be about one foot.
5.1.1.2 ` Area 2 —The area in the vicinity of Alhambra Drive, Glencoe
Avenue, Silver Lane and MacDonald Avenue,(northwest of Heil Avenue and.
Beach Boulevard is deficient in drainagejacilities such as curbs, gutters, and a
storm drain system: Depth of water is estimated to be about two feet during
periods of heavy rain.
5:1.1.3 Area.3 —This area north of Warner Avenue, west of Springdale
Street is situated lower than the adjacent C05 (East Garden Grove - Wintersburg
Channel) and is considered to be in a levee condition. The neighborhood
experiences offsife flows from Meadowlark Golf Course during periods of heavy
rain. The deficient storm drain system cannot handle flows even from a
moderate rain. Coupled with this drainage problem and subsidence that the
neighborhood has experienced, floodwater has been as deep as three feet
during periods of heavy rains. In 1995, water within the channel breached the
banks flooding the property to the east of the flood control channel.
21
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r3
Lark Lane area 1992 -
5.1.1.4 Area 4 —A deficient storm drain system results in two to three feet
of flooding at Rogers Drive and Remington Lane, southeast of Warner Avenue
and Graham Street during periods of heavy rain.
5.1.1.5 Area 5 - One to two feet of flooding results during periods of heavy
rain due to a deficient storm drain system in the Heil Avenue and Springdale
Street area.
5.1.1.6 Area 6 —A deficient storm drain system results in one to two feet of
flooding in the area of Shields Drive (north of Warner Avenue between
Springdale and Edwards Streets) during periods of heavy rain.
5.1.1.7 Area 7 —The deficient flood control channel north of Warner
Avenue at Goldenwest Street has overflowed during periods of heavy rains
causing two to three feet of flooding. The deficient storm drain in Goldenwest
Street north of Warner Avenue also causes flooding problems.
5.1.1.8 Area 8 — Heavy rain and deficient storm drain system result in three
to four feet of flooding in the area of Corsican Drive and Bardon Lane (west of
Gothard Street and north of Warner Avenue). This neighborhood is situated
lower than the surrounding area, and is considered to be in a levee condition
since it is located adjacent to the C05 (East Garden Grove —Wintersburg
Channel).
5.1.1.9 Area 9 — Deficient storm drain system results in one to two feet of
flooding in the Talbert Avenue and Springdale Street area during periods of
heavy rain.
22
5.1.1.10 Area 10 — Properties in the area of Michael Drive and Jefferson,
south of Slater Avenue are low lying areas. The�deficient storm drain system
results in two to three feet of flooding during periods of moderate rain. This area
experienced repetitive flooding.in 1974, 1978, 1979, 1982, 1983, 1985, 1989,
1992, 1993, 1994, 1995, 1997, and 1998. The 1983 event was so severe that
the National Guard patrolled the neighborhood after the residents were
evacuated.
k
5.1.1.11 Area 11 - Properties located in the Newman Avenue and Forest
`5 Lane area south of Area 10 have one to three feet of flooding during periods of
=Fi, heavy rain due to the deficient drainage system. Drainage from the cemetery,
which is located south of this neighborhood, flows directly into the low-lying
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properties located on Newman Avenue. This also compounds flooding impacts
in,Area 10.
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Good Shepherd Cemetery viewed from Newman Avenue - 1994 .
23
Water from Good Shepherd Cemetery flowing northerly across
Newman Avenue - 1995
5.1.1.12 Area 12 — Main and Seventeenth Streets experience one foot of
flooding during periods of heavy rain as result of the deficient storm drain system
including the lack of storm drains.
5.1.1.13 Area 13 — Main and Fourteenth Streets experience one foot of
flooding during periods of heavy rain as result of the deficient storm drain system.
5.1.1.14 Area 14 — Properties located between Seventh and Twenty-second
Streets south of Orange Avenue experience one to two feet of flooding during .
periods of heavy rain as result of the deficient storm drain system.
5.1.1.15 Area 15 —A mobilehome park west of Beach Boulevard and north
of Atlanta Avenue has one to two feet of flooding during periods of heavy rain
due to a deficient storm drain system including the lack of storm drains.
5.1.1.16 Area 16 —A large area east of Beach Boulevard and south of
Adams Avenue was seriously impacted during the 1983 rainy season. Heavy
rains and channel failure resulted in three to four feet of water.
24
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Indianapolis Avenue and Beach Boulevard area — 1983
5.1.1.17 Area 17 —The Newland Street/Hamilton Avenue area is deficient in
drainage facilities such as curbs, gutters, and a storm drain system. Depth of
water is estimated to be one to three during periods of heavy rain.
5.1.1.18 Area 18 — Portions of the condominium complex located at the
northwest corner of Atlanta Avenue and Magnolia Street experiences up to one
and one-half feet of water during heavy rains due to a deficient storm drain
system.
5.1.1.19 Area 19 — In the area south of Atlanta Avenue and Magnolia Street,
the earthen flood control channel failed and caused up to six feet of flooding.
5.1.1.20 Area 20 — Heavy rain and a deficient storm drain system results in
two feet of flooding in the area of Yorktown Avenue/ Bushard Street. In 1983,
water breached the banks of the flood control channel.
5.1.1.21 Area 21 — Mobilehome parks-located in the Garfield
Avenue/Brookhurst Street area are substantially lower than the adjacent flood
control channel. A deficient storm drain system results in four to six feet of
flooding in the area during periods of heavy rain. In 1983 and 1995, water
breached the banks of the flood control channel.
5.1.1.22 Area 22 - Properties located south of Adams Avenue and east of
Brookhurst Street, e.g., Meredith Gardens, drain into the Santa Ana River. The
25
deficient storm drain system does not allow proper drainage into the Santa Ana
River during periods of moderate rain. During the heavy rains such as 1983,
1995, 1997, and 1998, the area was flooded with three to four feet of water.
5.1.1.23 Area 23 — Heavy rain and a deficient storm drain system result in
one to two feet of flooding for southbound traffic on Bolsa Chica Street near
Bolsa Avenue.
5.1.1.24 Area 24 — Heavy rains and a deficient storm drain system cause
floodwaters up to two feet deep in the vicinity of Newland Street and Edinger
Avenue. Three county flood control channels are in the immediate area.
5.1.1.25 Area 25 —A deficient storm drain system results in one to two feet
of flooding in the area of Brookhurst and Bushard Streets during periods of heavy
rain.
5.1.1.26 Area 26 — Heavy rain accompanied with high tides (6.4 feet or
greater) impair drainage in the Huntington Harbour area. Depth of water is
estimated to be about one foot higher than the top of curb.
5.1.1.27 Area 27 — Heavy rain and a deficient storm drain system results in
one to two feet of flooding in the area of Twelfth and Lake Streets.
5.1.1.28 Area 28 — Properties in the Alabama Street, Utica Avenue, and
Detroit Street area south of Yorktown Avenue have deficient storm drains and
experience up to one foot of flooding during periods of heavy rain.
5.1.1.29 Area 29 — One foot of flooding is experienced in the Crabb Lane
and Speer Avenue area during periods of heavy rains due to lack of storm drains.
5.1.1.30 Area 30 —One to two feet of flooding water during periods of heavy
rain is the result of a deficient storm drain system (lack of storm drains) in the
area of Main Street and Garfield Avenue.
5.1.1.31 Area 31 — One foot or more of flooding impacts Pacific Coast
Highway from Warner Avenue to Goldenwest Street during periods of heavy rain
coupled with high tides.
5.1.2 Repetitive Loss Properties
Fifteen properties within the City have received flood insurance benefits twice
within a 10-year period since 1978 as a result of heavy rains. FEMA describes
these properties as Repetitive Loss Properties. The 15 properties represent 33
claims. These properties are located near the East Garden Grove - Wintersburg
Channel (C05), Talbert Channel (D02), East Valley— Fountain Valley Channel
(D05), Huntington Beach Channel (D01), Michael Channel, and the juncture of
26
three channels at Interstate 405, Beach Boulevard, and Edinger Avenue. All are
located in areas where localized flooding reoccurs. The majority of the claims
happened in 1995 and 1997-1998. Some of these flood claims were based on
the inadequacies of the local drainage system with the flood control channels full
of water; others were based on poor on-site drainage patterns.
During the 1992, 1995, and 1997-1998 flooding events for the repetitive loss
properties, the flood control channels were filled to capacity and floodwaters filled
the streets and continued to rise until homes were filled. High water levels were
maintained for several hours until rainfall diminished and the channel levels
receded to allow proper drainage. Repetitive loss properties at the lowest point
in neighborhoods where storm drain catch basins are located experienced a
deluge of water when heavy rains filled the channels to capacity. In many cases
the homes are lower than the channel and receive excess floodwater. In a
couple of instances, flood damage was a result of rain entering the dwelling
through windows and chimneys and yard grading which allowed water flow
directly toward the house.
5.1.3 Santa Ana River History
The earliest recorded flooding event occurred in 1810, when adobe buildings
were washed into the Santa Ana River. In 1825 the River changed its course
and created what is now known as the Balboa Peninsula. Storms in 1861-1862,
with constant rain for almost four weeks, created an inland sea in Orange County
when the peak flow of 320,000 cubic feet of water per second raged through the
Santa Ana Gap. Standing water approximately four feet deep up to four miles
from the river lasted about three weeks. This flooding is considered as having a
recurrence interval greater than a 200-year flood. Later in 1884, the river cut a
new channel. More serious flooding occurred in 1889.
Half a million dollars of damage and four deaths were the result of the river
running wild through most of western Orange County in 1916. Floods were also
recorded in 1925 and 1937, however, they did not match the disaster of 1938. At
that time an 8-foot wall of water swept out of the Santa Ana canyon leaving 19
dead. Water flows in the river measured 100,000 cubic feet per second. This
disaster led to the construction of the Prado Dam in 1941.
Twin floods of 1969 resulted in $21 million in damages and five deaths. Peak
water discharge flow reached 77,000 cubic feet per second above the Prado
Dam and 6,000 cubic feet per second below the dam. Emergency sandbagging
kept the river within its channel as it approached Huntington Beach on its way to
the ocean. On February 24, 1969, almost six inches of rain fell, overflowing
dams and flooding parks and canyons.
27
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5.2 HIGH TIDES AND HIGH SURF
When high tides and high surf occur simultaneously, portions of Pacific Coast
Highway are inundated with water. Portions of Pacific Coast Highway are often
flooded between Warner Avenue and Seapoint Street. The Public Works
Department works closely with the California State Department of Transportation
(CalTrans) to ensure that Pacific Coast Highway is protected as much as
possible from high surf damage. In the event that the roadway is inundated,
traffic is diverted and/or the highway is closed. In 1983, ocean waves reached
Pacific Coast Highway between Newland and Magnolia Streets.
Heavy rain, high surf, and high tides impact the beaches along Huntington
Beach's shoreline. Bolsa Chica State Beach has been inundated by high surf
conditions. Areas of the beach, multi-purpose trail, restroom and parking lot
areas were flooded. Park facilities were lost to high surf and storm conditions in
1983. The beach is also inundated by debris that washes ashore from the San
Gabriel River. Huntington State Beach is impacted by debris that washes onto
the beach from flooding impacts upstream along the Santa AnaAver. High tides
and high surf conditions also erode the beach sand.
High tides coupled with heavy rain force stormwater to back up in the flood
control channels. This backup may create water to breach the channels. Public
Works Department monitors the tide table on a regular basis. When the table
indicates a high tide greater than six feet will occur, inflatable bags are placed in
storm drains to prevent salt-water intrusion into the local drainage channels
within the Sunset Beach area, northwest of Warner to Intrepid Island.
Tidal surge was experienced in the Huntington Harbour area following an
earthquake in Alaska during 1964. Sandbagging efforts by City personnel and
local residents minimized damage to the area.
5.3 TORNADOS
In 1978 a waterspout came in off the coast of Huntington Beach causing a
tornado that hit Huntington-by-the Sea Mobilehome Park located near Newland
Street and Pacific Coast Highway. About 45 mobilehomes were destroyed or
seriously damaged. This event led to the creation of an emergency response
team program.
In 1991 a waterspout came inland causing a tornado that hit Driftwood
Mobilehome Park and some residences in the Altanta Avenue and Newland
Street area. About 40 mobilehomes and two other residences suffered moderate
damage; five residences had minor damage. The City responded to the incident
along with the American Red Cross. Canteens were set up along with mental
health professionals to attend to the personal needs of the victims. There were
28
no injuries and no temporary shelter was required. Since the homeowners were
insured from this type of loss, the event was not proclaimed a local emergency.
In 1998 a tornado hit the Villa Huntington Mobile Estates located south of Slater
Avenue and west of Beach Boulevard. A storage shed and several roofs were
-. blown away by the powerful wind. Traffic signals were non-functioning and
.. power outage lasted approximately two hours in the immediate area.
5.4 BUILDINGS
R There are over 70,000 buildings in Huntington Beach. Of these approximately
- 54,500 are 1-4 family structures. Five buildings are listed on the National
. Register of Historical Structures.
5.4.1 Public Buildings
Included in the total number of buildings are the following public facilities:
5 police stations
8 fire stations (one under construction)
.- 1 marine safety building
1 city hall
1 community college
4 high schools
43 elementary and middle schools
5 libraries
3 post offices
4 public maintenance facilities (beaches, public works
corporate yard, parks, and water operations)
5 community centers
1 art center
1 parking structure
Flood impacts on these buildings may hamper the City's normal operations, flood
assistance efforts, and temporary shelter for displaced persons.
5.4.2 Historic/Local Landmarks .
The City's General Plan identifies many local landmarks considered to be of
significant importance to the community. Five of the identified landmarks are
listed on the National Register of Federal Historic Places. They are: Newland
House, Heim House Furnishing Company, Helm-Worthy House, Garner House,
and the City Gym:and pool, which are still used for the original purpose. All are
located in repetitive loss areas except the Newland House.
Other landmarks include areas of archeological significance such as Edwards Hill
and Bartlett Park, and areas where structures constructed during the early 1900s
29
such as the Townlot area still exist. Flood damage to these properties may
significantly diminish their historic value.
5.4.3 Critical Facilities
Flooding can impact critical facilities. Critical facilities that may need special
attention include one 133-bed hospital and three nursing/rehabilitation centers
with a combined total of 448 beds. It is important that ensure safe evacuation
procedures can be attained with minimal disruption.
Other critical facilities include the electrical generation plant, four electrical
substations, and 42 bridges. Flooding at any of the electrical facilities may cause
power outages or shortages. If damage occurs to any of the bridges crossing the
flood control channels or Santa Ana River, evacuation routes may be seriously
hampered.
5.4.4 Hazardous Chemical Facilities
Large expansive sites with hazardous materials include Boeing which has 50
percent of all hazardous chemicals in the City, the water and sewage treatment
facility, rotary mud dumpsite, major oil company storage facilities, and the oil
fields along Pacific Coast Highway and scattered in the Holly-Seacliff and
downtown areas. Businesses that store or use hazardous chemicals are
monitored by the Fire Department and are identified in the City's Emergency
Management Plan. A combination of hazardous materials and floodwaters may
be detrimental to life, property, and the environment.
5.5 WETLANDS, UNDEVELOPED PROPERTIES, AND OPEN SPACE
AREAS
As previously mentioned, wetlands are designed by nature to hold water and
provide habitat for wildlife. When the floodwaters enter the site, problems may
occur if the runoff water contains hazardous substances. Waters then become
contaminated and wildlife-feeding or nesting areas are affected. Recent oil spills
at sea have impacted the shore and wetland areas and necessitated significant
cleanup efforts. The Talbert Marsh is a restored wetland and lies inland of
Pacific Coast Highway between Brookhurst Street and the Santa Ana River. The
Talbert Channel flows through the area and exits into the ocean. The Bolsa
Chica Wetland located near Pacific Coast Highway and Warner Avenue is
surrounded by the City but lies outside the city limits. (See Exhibit 4.)
Huntington Beach has 71 parks, which encompass 577.28 acres. The many
local public school sites provide additional open space areas. The park areas, as
well as undeveloped areas and play fields adjacent to public schools, have
pervious ground surfaces that absorb water naturally and may also.contain
floodwaters. Within the parks there are lakes that also act as retention basins for
30
heavy rains. The lakes include Talbert Lake, Huntington Lake, Shipley Lake,
Carr Park Lake, and Sully-Miller Lake. There are also retention areas within
Bartlett Park, Good Shepherd Cemetery, Ocean View High School, Oka
Elementary School, Argosy Drive east of Graham Street, Home Depot, and
adjacent to the equestrian center on Goldenwest Street. There are relatively few
areas in the city that have not been developed and/or are vacant. These are
depicted in the Vacant Land Survey available in the Planning Department.
Preventive measures must be observed to ensure that mudflow is not generated
from any vacant/undeveloped site.
5.6 PROTECTIVE MEASURES IN EFFECT OR UNDER CONSTRUCTION
5.6.1 Santa Ana River Mainstem Project
Almost thirty years ago planning efforts began to tame the Santa Ana River,
which is the greatest flood threat west of the Mississippi River. This project is
known as the Santa Ana River Mainstem Project and cost$1.4 billion. A
coordinated effort between local, county, state and federal agencies and the
business community was realized in 1990 when land was cleared in preparation
of construction of the Seven Oaks Dam, a 550-foot high, 3,000-foot-long dam, in
San Bernardino County. In 1991 construction began on the lower three miles of
the riverbed from Adams Avenue to the Pacific Ocean. The river channel
adjacent to Huntington Beach was deepened, widened, and lined with concrete.
Later the remaining portion of the river in Orange County was completed or is
near completion. The Seven Oaks Dam was completed in 1999. These
measures protect Huntington Beach from a 100-year flood.
A core component of the Santa Ana River Mainstem Project includes the
increase in the Prado Dam's capacity to maintain a major flood. The Prado Dam
will be raised 28.4 feet and approximately 2,000 acres added to accommodate
the reservoir behind it. This portion of the project when completed will provide
protection to the City of Huntington Beach from a 190-year flood. Lack of
sufficient funding sources and the Orange County bankruptcy have impacted the
progress of the Prado Dam. Recent Federal legislation has appropriated partial
funds for this project. The anticipated completion date is expected by 2005.
Prado Dam expenses are estimated to be $470 million.
5.6.2 County Projects
Following the March 1983 storm, the County intermittently made repairs to its
channels. This storm devastated over 100 homes within the Talbert Gap area in
southeastern Huntington Beach. Repairs were made to the D01 (Huntington
Beach) Channel where channel failure occurred and up to five feet of flooding
impacted properties adjacent to the channel. D05 (East Fountain Valley) and
D02 (Talbert) Channels were concrete lined at Brookhurst Street and Garfield
Avenue where extensive damage occurred to many mobilehomes.
31
The Talbert Gap outlet was moved 300 feet northwest of the Santa Ana River
bridge on Pacific Coast Highway. Reconstruction of the Santa Ana River bridge
and Pacific Coast Highway were completed in late 1989. At that time the County
granted a conservation easement and fee title to the Huntington Beach Wetland
Conservancy to control and manage restoration of a wetlands and wildlife area of
25 acres adjacent to the outlet.
In the last 10 years in conjunction with the Santa Ana River Mainstem project, the
County has an on-going program to improve, and has constructed portions of
several channels to provide 100-year protection. . Prior to improving a channel,
the County requires reports for each channel that assess the current capacity
and demand. They have contracted with various engineering firms to study the
various flood control channels and to prepare a recommendation for
improvements to meet the 100-year flood capacity. Recently a report for the
Talbert Channel was prepared and completed which resulted in on-going
improvements.
Since 1989 the County has been making improvements to the Talbert and
Huntington Beach channels to increase the capacity to 100-year flood protection.
Vertical steel sheet piling has been installed to increase the channels' capacity.
Orange County's consultant is presently conducting flood studies to determine
the necessary changes to improve the remaining County channels to comply with
the 100-year minimum capacity. These studies should be completed in the next
five years. Until the studies are complete and accepted by FEMA, properties in
the SFHA for the D01, D02, and D05 channels will remain as flood zone A99 and
the properties in the SFHA for the C05 and C06 channels will remain flood zone
A. When completed, these channels will be eligible for improvements by the
County as funding permits.
Local property tax assessments generate funding for County flood control
measures. Funding is also received form FEMA's Hazard Mitigation Grant
program and the U.S. Army Corps of Engineers. The County has a seven-year
plan for drainage improvements to FEMA's 100-year minimum standard. Only
porjects shown in the first year are recommended for inclusion in the budget. All
others are subject to change. Flood control improvements for channels within
Huntington Beach that are included in the seven-year plan are shown on the next
page.
32
COUNTY OF ORANGE SEVEN-YEAR FLOOD CONTROL
IMPROVEMENT PLAN
Fiscal Channel ,Loon cati $ Estimate
s
2000-2001 C05 Near Gothard and railroad bridge 2,750,000
D01 1,750 ft upstream of Newland to 4,500,000
Atlanta
D02 Indianapolis to Adams 500,000
D02 Atlanta to Indianapolis 500,000
2001-2002 C05 Quartz to Magnolia/Edinger 2,300,000
D01 Magnolia to 1,750 ft. upstream of 6,400,000
Newland
2002-2003 C05 Magnolia/Edinger to Bushard 5,300,000
D01 Atlanta to Indianapolis 2,600,000
D02 Adams to Yorktown 4,850,000
2003-2004 C05 Bushard to 1600 ft. upstream 4,000,000
2004-2005 D01 Indianapolis to Adams 5,000,000
2005-2006 None
2006-2007 C05 1600 ft. upstream Bushard to 3,000,000
Brookhurst
C06 Bushard to Brookhurst 1,300,000
Total 43,000,000
Since 1987, the County has spent $25 million on D- drainage systems with a total
of$32.6 million on both C- and D- drainage systems within the county that
directly or indirectly benefit the City.
Completion of the entire county channel improvements in Huntington Beach is
anticipated to occur within the next 10-15 years barring any unforeseen
catastrophes. All improvements should ideally begin at the lowest portion of the
channel with the work progressing upstream so that the completed portions are
capable of containing water from a 100-year storm. The County, however,
improves portions of the channels in various areas of the county that will provide
protection and not create additional flood problems in other areas.
33
Until these improvements are completed, certified by FEMA, and the official flood
maps are revised, properties located within 100-year flood areas are subject to
flood loss and flood insurance requirements. Projects that can increase the flood
intervals will enjoy less possibility of flood damage and are not required to be
insured from flood damage.
A Letter of Amendment was issued by FEMA for 100-year protection
improvements to the Anaheim-Barber Channel (CO3) effective February 28,
1996. These improvements protect properties in north Huntington Beach
between Rancho Road and Springdale Street adjacent to the City of Westminster
from a 100-year flood. Therefore, flood insurance is not required for these
properties.
5.6.3 Local Projects
There are many local flood control projects that have been completed, under
construction, or pending final improvement. These include: -
➢ Curbs and gutters have been constructed in Repetitive Flooding Area 2, but
there is still more to complete.
➢ Additional catch basins have been constructed in Repetitive Flooding Area
10, however, flooding still remains a concern until additional measures are
undertaken.
➢ The Main Street/Garfield Avenue area (Repetitive Flooding Area 14) has
been improved with new paving, curb and gutters, which should alleviate
future flooding problems in this area.
➢ A pump was added to the pump station in Repetitive Flooding Area 20, but
the station is too small to solve the flooding problem.
➢ Demolition and reconstruction of the existing deficient Shields pump station is
underway. It is scheduled for completion by October 2001 (Repetitive
Flooding Area 6).
➢ In Repetitive Flooding Area 7 construction of a new storm drain and
appurtenances in Goldenwest Street between the C05 channel and Norma
Drive is scheduled for completion by October 2000.
➢ Construction of the Slater Channel improvements began on May 30, 1999,
with an anticipated completion date of February 2001. The project consists of
concrete lining the existing channel and appurtenances between Springdale
and Goldenwest Streets.
34
➢ Murdy Channel realignment will provide 400 feet of new channel at the
confluence with the C05 channel. This project is awaiting final clearance from
the US Army Corps of Engineers.
➢ Funding from the Community Development Block Grant program has been
allocated to study, design, and construct improvements to the Michael
Channel (Repetitive Flooding Area 10).
➢ The City has funded installation of a new storm drain and appurtenances
such as additional inlets and flap gates for Intrepid Lane.
Prior to the rainy season each year, the Public Works Department inspects,
cleans and maintains the City's flood control channels.
Rain gauge readings are taken at the Lake Street Fire Station and forwarded to
the Public Works Department, maintenance division, for advance possible flood
warning. During and prior to predicted heavy rain, the Public Works Department
rain patrol checks areas known to have experienced flood ing"inthe past.
Barricades are placed at intersections, sand bags placed in strategic locations,
and storm drains inspected for debris accumulation and cleaned as needed.
Sandbags are made available to the public at the City Yard if time permits.
Citizen volunteers such as Community Emergency Response Team (CERT) and
Radio Amateur Civil Emergency Services (RACES) provide flood protection and
assistance to the City and to property owners
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Community volunteers assisting in sandbagging
35
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Community Emergency Response Team (CERT) volunteers
5.6.4 Flood Insurance
As a participant in the NFIP, flood insurance is available to Huntington Beach
property owners and tenants whether or not the property is located in the SFHA
as identified by FEMA. Flood insurance is required for all properties in the SFHA
with mortgages backed by the federal government. There are 17,495 structures
in the City insured for $2.5 billion against flood damage. Currently a total of
approximately $6.7 million in flood insurance premiums are paid annually for
17',381 written policies for those structures. Since 1983, 826 flood insurance
claims valued at $2.3 million have been paid to local citizens due to heavy rains
and channel malfunctions. Many property owners who suffered flood damage in
March 1983 were not insured from flood loss. These citizens were able to
receive low interest loans to repair the damage.
In 1996 the Santa Ana River floodplain in Orange County was determined by
FEMA to be protected from a 100-year flood by a project under construction.
This determination led to the issuance of new flood insurance rate maps (FIRMs)
that identify much of the city within a special flood hazard area. The new FIRMs
rezoned most of the city to flood zone A99 effective January 3, 1997. Following
certification of the Santa Ana River improvements, the FIRMs were again revised
rezoning portions flood zone A99 to flood zone A due to localized flood hazards
from County and City owned channels. Approximately one square mile of zone A
was added to an area previously outside of A99 and approximately five percent
of zone A99 was added to zone X. These maps became effective June 14,
2000. (See Exhibit 17.)
36
5.6.5 Seawalls
Huntington Harbour is an area consisting of several man-made islands.
Seawalls have been constructed along the perimeter of the islands to protect the
development from the high tides. The seawalls are owned and maintained by the
adjacent development project. A few have been reconstructed in the past few
years due to deterioration.
A seawall/levee also protects a residential development near the juncture of
Talbert Avenue and Graham Street along the City boundary from ocean intrusion
from the Bolsa Chica wetland area.
5.6.6 Warning Systems and Evacuation
A major nonstructural flood protection measure is the National Warning System
(NAWAS). This system identifies severe weather conditions and tsunamis, and
is operated by the National Oceanic and Atmospheric Admihistrafion through the
National Weather Service. The National Weather Service cooperates with State,
County, and local officials to alert coastal residents when major storms or
tsunamis necessitate precautionary measures be undertaken.
The California State Warning System receives information from the NAWAS at
the State Office of Emergency Services (OES) headquarters in Sacramento.
This system extends to the Orange County Operational Area (storm center),
which advises local jurisdictions.
During a major storm, the Orange County Storm Center is activated. This center
provides predicted flood events and related data to the City's Emergency
Operation Center (EOC) which is located at City Hall. EOC is a state of the art
facility that was funded in part by FEMA and is activated when a threat to the City
is imminent. EOC has established operation procedures for emergencies
including flooding.
When the City receives flood warnings or a threat exists, flood warnings are
disseminated over local radio stations KWVE (107.9 FM) and KXMX (95.9 FM)
utilizing Emergency Alerting Systems and local cable TV HBTV-3 (Channel 3). If
EOC determines that evacuation is necessary, the City's warning sirens located
at each fire station will be sounded. This alerts area residents to check the radio
or television for further information and advice. Other forms of notification may
include helicopter and vehicle public address loud speakers and door-to-door
canvassers.
The Police Department is responsible for alerting and warning the public in areas
where flooding is imminent. The Fire Department assists in evacuating non-
37
ambulatory citizens. Marine Safety staff assists in areas where boats may be
used for evacuation.
5.6.7 Zoning and Construction Regulations
The City has adopted floodplain development regulations to ensure that new
projects are constructed in a flood safe manner. At the time a property owner
desires to develop a vacant site, planning and zoning approval must be received
to confirm that the project complies with local zoning requirements including
floodplain development regulations. Building and grading permits must be issued
that confirm the development will be designed and constructed in compliance
with drainage and building codes adopted by the City. New development must
also comply with the National Pollution Discharge Elimination System (NPDES)
requirements to ensure that runoff from the site does not affect any water source.
Prior to final building permit inspection, an elevation certificate must be submitted
verifying that a building constructed in the floodplain was elevated one foot above
the base flood elevation.
5.6.8 Beach/Wetland Protection
The State Department of Parks and Recreation participates with the County,
State Department of Boating and Waterways, and the US Army Corps of
Engineers in the regional sand replenishment project that occurs on a five-year
cycle. This ensures that there is adequate sandy beach to minimize flooding of
property from ocean activity. Relocating a beach park vehicle exit and
constructing a tall sand berm to prevent surf waters from flooding Pacific Coast
Highway has mitigated loss of state beach facilities.
Sand dunes protect the fresh water wetlands along Pacific Coast Highway
between Magnolia and Brookhurst Streets. As mentioned in Section 5.6.7, a
seawall/levee protects a residential neighborhood along the southwesterly City
boundary and also provides protection from neighborhood drainage into the
wetlands.
5.7 FISCAL IMPACT
5.7.1 Funding
Current funding for City drainage improvements is derived from the City's
General Fund and drainage fees from developers. Drainage fees are assessed
on new construction and used only in the drainage area where the construction
occurs. As a result, drainage districts with new development areas such as
Holly-Seacliff receive more funding than a district with older neighborhoods and
little or no new construction. Improvements in other areas must be budgeted and
authorized by the City Council.
38
J
Grant funding is a possible source of revenue for drainage improvements. The
City has received funding from several sources including FEMA, the California
Office of Emergency Services, and the Community Development Block Grant
(CDBG) program.
5.7.2 Flood Damage Expenses
The City incurs expense from flooding events. These expenses include
activation of the EOC; barricading streets; patrol, clean up of mud, water, and
debris; and fallen tree removal and replacement. EOC activation along with
damage and response costs to the City since 1988 are over $4 million and
include:
1988 Winter storm and pier damage $ 1,300,000
1992 Flooding $ 104,000
1995 Flooding $2,600,000*
1997 El Nino Flooding $ 160,000
1998 El Nino Flooding $ 112,000
Total $ 4,276,000
*The City was declared a disaster site on January 5, 1995, following the heavy rains that
deluged Huntington Beach. Cities are eligible to receive financial assistance following a
disaster that enables them to recover from the natural disaster. FEMA reimburses a
maximum of 75% of the eligible damage and response costs. Consequently, a claim
was submitted to FEMA to recover the expenses incurred from the flood disaster. A few
of the expenses are listed on the next page.
39
1995 FEMA CLAIM
ITEMS - COSTS
Marine Safety response $14,320
Fire Department response $5,102
Police Department response $9,502
Public Works response $70,558
Trees $25,018
Sewer line cave-in $18,166
Street repairs $10,412
Sea curtains $13,496
Trash racks $10,625
Prince park $110,025
Debris removal $48,001
Slater Channel -$235,690*
Bluffto Park $1,943,604
Natural gas $21,195
Lifeguard tower $2,435
Horse stables $5,072
Corsican Channel $14,312
Slater Channel temporary repairs $20,026
*This cost was deobligated but resulted in a final obligation of$909,934.
5.7.3 Flood Management/Prevention Expenses
The Planning Department sends an annual flood protection/information brochure
to over 26,000 residents located in the floodplain. This brochure includes a flood
map, flood warning and flood insurance information, property protection
suggestions, flood safety tips, and local flooding history. Printing and mailing
cost are approximately $6,000. The winter edition of the Sands, a Community
Services activities publication, also includes much of the same information
Total yearly average cost for flood management/prevention by the Public Works
Department maintenance crews is $101,815. This includes:
• Annual local drainage channel inspection and
cleaning $23,697
• storm preparations $50,048
• storm duty $21,302
• high tide patrol $6,767
40
Currently the City operates 15 pump stations with 47 pumps with an annual
maintenance and operational budget of$300,000 or approximately $6,400 per
pump. The actual maintenance and operational costs are closer to $1,000,000
or approximately $21,280 per pump. Property operating procedures should
include regularly scheduled equipment maintenance, replacement, and cleaning.
The replacement cost for a single pump with appurtenances is estimated at
$900,000.
5.7.4 Financial Assistance
During 1998, the City received FEMA mitigation grant funding of$3.3 million for
Slater Channel and $468,000 to realign Murdy Channel. In 1999, $1.6 million
FEMA mitigation grant funding was received for Shields pump station.
In November 1999, $300,000 in federal funds was received to study the bluff
erosion along Pacific Coast Highway and to determine mitigation measures.
Total cost of the 27-month study is estimated at $1.02 million. The City expects
to apply for an additional $210,000 grant in 2000 and provide matching funds for
the project.
In late 1999, the City received $425,000 in reimbursement by the federal
government for the City's handling of floods caused by severe storms in past
years.
In 2000, the City received $397,800 in CDBG funds for the Michael Channel.
These grants will be used to complete the flood-related projects identified in the
City's Capital Improvement Program during fiscal years 1999-2000 and
2000-2001. These projects are shown on below.
IMPROVEMENT CITY $ FEMA $ CDBG $ TOTAL $
Goldenwest St. storm 346,540 0 0 346,540
drain
Slater Channel 827,484 2,482,480 0 3,309,964
Shields pump station 611,664 1,245,000 0 1,856,664
Murdy Channel 106,250 318,750 0 425,000
realignment
Intrepid Ln. storm 130,000 0 0 130,000
drain
Michael Channel 0 0 397,800 397,800
Total 2,021,938 4,046,230 397,800 6,465,968
41
SECTION 6.0
GOALS
6.0 GOALS
The Flood Management Plan Committee reviewed the goals of the Huntington
Beach General Plan and seven were found to be appropriate to the Flood
Management Plan.
❖ Flooding (EH4): Eliminate to the greatest degree possible, the risk from flood
hazards to life, property, public investment and social order in the City.
❖ Storm Drainage (1-13): Provide a flood control system which is able to support
the permitted land uses while preserving the public safety; upgrade existing
deficient systems and pursue funding sources to reduce the costs of flood
control to the City.
❖ Tsunami (EH5): Protect human life, to the greatest extent feasible, from
tsunamis and seiche hazards.
❖ Biological Resources (ERC2): Protect and preserve significant habitats of
plant and wildlife species, including wetlands for their intrinsic values.
❖ Erosion (EH2): Reduce the potential threat for mesa edge and bluff erosion
hazards, and the potential for beach sand loss.
❖ Open Space (LU14): Preserve the City's open space.
❖ Historical Resources (HCR1): Promote the preservation and restoration of the
sites, structures and districts which have architectural, historical, and/or
archaeological significance to the City of Huntington Beach.
42
Y
SECTION 7.0
POSSIBLE ACTIVITIES
7.0 POSSIBLE ACTIVITIES
The CRS guidelines require the FMP to identify all the activities considered by
the Committee and state why an activity was not recommended in Section 8.0.
The Committee considered many possible ways to reduce flood losses and to
attain the goals applicable to the Flood Management Plan.
At almost every meeting, the Committee stated that the County's regional
drainage system affects flooding in Huntington Beach and that the City should be
pro-active in all developments in the regional drainage area. There was
considerable concern that most of the flood control channels (both City and
County owned) were not in compliance with FEMA's 100-year standard. The
storm drains, channels and pump stations should be improved to this standard as
soon as economically possible. Until the systems are upgraded, the Committee
believes that development should be limited to minimize future flooding impacts.
Whenever private property drainage problems are created by water flow from
public property, it should be corrected. The Committee believes that the Master
Plan of Drainage should be updated and implemented on an annual or biennial
basis. Many of the activities cited in the CRS application were specifically
recommended to continue to be implemented.
The following activities were discussed but are not recommended for
implementation:
• Limit development until flood control deficiencies corrected
• Become involved in all projects in regional drainage area
• Establish citywide drainage fee
• Building acquisition or relocation
For the following reasons:
• Drainage studies and improvement plans are required to ensure no
drainage impact to surrounding area.
• Projects in northern part of drainage area are not forwarded to the city for
review and comment.
• City Council will review funding recommendations from the infrastructure
committee.
• Insufficient funds to acquire/relocate floodprone buildings.
The activities recommended in Section 8.0 were then compared to the six
mitigation categories suggested by FEMA. Each of the categories has two or
more recommended activities to mitigate flood hazard to the city.
Preventive: Activities that include planning and zoning, open space preservation,
floodplain regulations, drainage system maintenance, stormwater management,
43
and dune and beach maintenance. These are usually enforced by Planning,
Building, and Public Works Departments.
Property Protection: These activities are usually undertaken by property owners
on a case-by-case basis and include relocation, acquisition, building elevation,
floodproofing, sewer backup protection, and insurance.
Natural Resource Protection: Activities that preserve or restore natural areas or
the natural functions of floodplains include erosion and sediment control, best
management practices, and wetland protection. These are implemented by the
Planning and Public Works Departments.
Emergency Services: Activities that are undertaken during a flood to minimize its
impact include warning and evacuation, critical facility protection, and health and
safety maintenance. These activities are the responsibility of the Emergency
Operations Center (EOC), safety personnel (Fire, Police, and Marine Safety),
and Public Works Department.
Structural Proiects: Activities that keep floodwaters away from an area include
seawalls, water diversion, channel modifications, beach nourishment, and storm
drainage system improvements. They are designed by engineers and managed
by city and county public works staff.
Public Information: Activities that advise property and business owners about the
hazards, ways to protect people and property from flood damage, and the natural
and beneficial functions of the local floodplain are implemented by the Planning
Department. The Library, EOC, and the Public Information office may provide
assistance.
44
SECTION 8.0
RECOMMENDATION
8.0 RECOMMENDATION
The Committee recommends the following activities. These activities will achieve
the goals of the Flood Management Plan and General Plan and will supplement
the implementation programs identified in the General Plan. Existing and/or
similar General Plan implementation programs are shown in parenthesis.
8.1 Goal EH4 - Flooding: Eliminate to the greatest degree possible, the risk
from flood hazards to life, property, public investment and social order in the City.
8.1.1 Continue to enforce and update floodplain regulations when revised by the
Federal government (I-EH 15)
Responsible department: Planning
Funding source: - General fund
Timetable: ongoing
8.1.2 Protect public facilities from flooding (I-EH 2d) _
Responsible department: Public Works
Funding source: General fund
Timetable: ongoing
8.1.3 Assist managers and owners of critical facilities as listed in Section 5.5.3
to develop flood protection plans
Responsible department: Fire (Emergency Services)
Funding source: General fund
Timetable: ongoing
8.1.4 Encourage floodproofing and retrofitting property/structures to prevent
substantial flood damage and provide technical information (I-EH 1-b)
Responsible department: Planning, Building, Fire (Emergency
Services)
Funding source: not applicable
Timetable: ongoing
8.1.5 Continue to update, distribute, and provide flood protection information
and materials (I-EH 8a)
Responsible department: Planning, Library, and Fire (Emergency
Services)
Funding source: General fund
Timetable: ongoing
45
8.1.6 Maintain adequate flood insurance on public structures
Responsible department: Administrative Services
Funding source: General fund
Timetable: ongoing
8.1.7 Provide floodplain information to property and business owners, realtors, and prospective
buyers and encourage flood insurance (I-EH 8d)
Responsible department: Planning
Funding source: not applicable
Timetable: ongoing
8.1.8 Maintain close liaison with nearby cities and with County, State and Federal agencies (I-
EH ex and 1-EH 2h)
Responsible department: Public Works, Planning and Administration
Funding source: not applicable
Timetable: ongoing
8.1.9 Continue to participate in the National Flood Insurance Program and Community Rating
System (I-EH 14)
Responsible department. Administration and Planning
Funding source: General fund
Timetable: ongoing
8.1.10 Continue to implement the City's emergency operation procedures as outlined in the
City's Emergency Management Plan, in particular, the Flood Warning and Evacuation
procedures (I-EH 13b)
Responsible department: Fire(Emergency Services)
Funding source: General fund
Timetable: ongoing
8.1.11 Continue to utilize citizen volunteers, e.g., CERT and RACES (I-EH 13c)
Responsible department: Fire(Emergency Services)
Funding source: General fund
Timetable: ongoing
8.1.12 Continue to provide a sandbag program
Responsible department. Public Works
Funding source: General fund
Timetable: ongoing
8.1.13 Encourage the State to modify the roadway profile of Pacific Coast Highway
between Warner Avenue and Goldenwest Street to prevent street closure due to
flooding.
Responsible department. Public Works,Administration, Planning
Funding source: General fund
Timetable: January 2001
46
8.2 Goal U3 - Storm Drainage: Provide a flood control system which is able
to support the permitted land uses while preserving the public safety; upgrade
existing deficient systems and pursue funding sources to reduce the costs of
flood control to the City.
8.2.1 Upgrade the City's flood control system (storm drains, catch basins, pump
stations, and channels) to current FEMA standards (100-year flood) and
concentrate on the repetitive flood areas first. (I-EH 1a)
Responsible department: Public Works
Funding source: General fund, Capital improvement
program, drainage fees, FEMA
mitigation funds, Community
Development Block Grant funds
Timetable: October 2020
8.2.2 Quarterly the City Council shall lobby the County to correct, upgrade, and
maintain the County's flood control system in the city to current FEMA
standards (100-year flood) _
Responsible department: City Council
Funding source: General fund
Timetable: by January 2001 and quarterly
thereafter
8.2.3 Evaluate existing street conditions for replacement and/or installation of
facilities to allow proper conveyance of storm flows to the city's flood
control systems (1-U3 9)
Responsible department: Public Works
Funding source: Measure "M", Gas tax, General fund
Timetable: January 2010
8.2.4 Maintain the City's flood control system and continue biannual inspection
and cleaning of City's flood control system (I-EH 1a)
Responsible department: Public Works
Funding source: General fund
Timetable: ongoing
8.2.5 Update the City's Master Plan of Drainage to evaluate the effectiveness of
the City's flood control system (I-EH la and 1-U 4)
Responsible department: Public Works
Funding source: General fund, drainage fees
Timetable: October 2001
47
8.2.6 Lobby the federal, state and county governments to study, pursue and
expand the wetlands from Beach Boulevard to Brookhurst Street for
floodwater mitigation.
Responsible department: Public Works, Administration, Planning
Funding source: General fund
Timetable: ongoing
8.2.7 Evaluate and upgrade open areas, e.g., Meadowlark Golf Course, Central
Park, Good Shepherd Cemetery, to eliminate offsite drainage and
subsequent impact to private property
Responsible department: Public Works
Funding source: to be determined
Timetable: ongoing
8.2.8 Continue to support reconstruction of deteriorating seawalls
Responsible department: Planning _
Funding source: not applicable
Timetable: ongoing
8.2.9 Pursue funding from County, State and Federal agencies (1-U 6)
Responsible department: Public Works and Administration
Funding source: not applicable
Timetable: ongoing
8.2.10 Develop and support new funding sources to help accomplish drainage
goals
Responsible department. Public Works, Administration,
Administrative Services
Funding source: to be determined
Timetable: ongoing
8.2.11 Continue to participate in County watershed studies and programs
Responsible department: Public Works
Funding source: General fund
Timetable: ongoing
48
8.3 Goal EH5 -Tsunami: Protect human life, to the greatest extent feasible,
from tsunamis and seiche hazards.
8.3.1 Update the Tsunami Emergency Operation plan, Operations Plan — 2, as
needed (I-EH 2a)
Responsible department: Fire (Emergency Services)
Funding source: General fund
Timetable: ongoing
8.3.2. Continue to provide tsunami warning to the community (I-EH 17)
Responsible department: Fire (Emergency Services)
Funding source: General fund
Timetable: ongoing
8.3.3 Educate the public regarding the potential threat of a tsunami
Responsible department: Fire (Emergency Services)
Funding source: General fund
Timetable: ongoing
8.4 Goal ERC2 - Bological Resources: Protect and preserve significant
habitats of plant and wildlife species, including wetlands for their intrinsic values.
8.4.1 Implement best management practice plans and National Pollution
Discharge Elimination Plans (1-U 1)
Responsible department: Public Works and Planning
Funding source: General fund
Timetable: ongoing
8.4.2 Investigate and install in-line wetlands in drainage courses where ever
feasible
Responsible department: Public Works
Funding source: General fund, Drainage fees, FEMA
mitigation funds, Community Block
Grant funds
Timetable: ongoing
8.4.3 Prohibit filling of wetlands except as permitted by the General Plan
(I-ERC 1 e)
Responsible department: Planning
Funding source: not applicable
Timetable: ongoing
49
8.4.4 Encourage the State to maintain the coastal dunes adjacent to the Bolsa
Chica Wetlands and in the Huntington Beach Wetlands to better protect
the areas from storm surges
Responsible department: Community Services
Funding source: General fund
Timetable: ongoing
8.4.5 Continue the. Coastal Conservation District zoning on the wetlands
Responsible department: Planning
Funding source: not applicable
Timetable: ongoing
8.5 Goal EH2 — Erosion: Reduce the potential threat for mesa edge and bluff
erosion hazards, and the potential for beach sand loss.
8.5.1 Establish building setbacks from all slopes including mesa and bluff edges
Responsible department: Planning
Funding source: General fund
Timetable: October 2002
8.5.2 Participate in the bluff (between Goldenwest and Seapoint Streets)
erosion study and implement recommendations
Responsible department: Public Works
Funding source: General fund
Timetable: ongoing
8.6 Goal LU14 - Open Space: Preserve the City's open space.
8.6.1 Limit construction in existing open space areas only to necessary
structures such as restrooms, picnic shelters
Responsible department. Planning and Community Services
Funding source: not applicable
Timetable: ongoing
8.6.2 Evaluate the possibility of the City purchasing surplus school sites to allow
playfields to remain as open areas and provide for floodwater retention
areas
Responsible department: Community Services
Funding source:. General fund
Timetable: ongoing
50
8.7 Goal HCR1 - Historical Resources: Promote the preservation and
restoration of the sites, structures and districts which have architectural,
historical, and/or archaeological significance to the City of Huntington
Beach.
8.7.1 Encourage property owners to floodproof historical structures (I-EH 1b)
Responsible department: Planning
Funding source: General fund
Timetable: ongoing
8.7.2 Encourage property owners of historical structures to maintain adequate
flood insurance (I-EH 8d)
Responsible department: Planning
Funding source: - General fund
Timetable: ongoing
8.8 Recommended Activities Matrix (see following pages)_
51
Flood Management Plan Recommended Activities
C Y C > d O
C O U. D U C C U
c — .0 Z o Z
C . 3 '5 1 L� m Ern
a u °° cN c 0
'� •E V V
rL a a
Goal Activity Responsible Department Schedule Status
EH4-Flooding 8.1.1 -Continue to enforce and update floodplain X Ongoing
regulations when revised by the Federal
government
8.1.2-Protect public facilities from flooding X Ongoing
8.1.3-Assist managers and owners of critical X Ongoing
facilities as listed in Section 5.5.3 to develop flood
protection plans
8.1.4-Encourage floodproofing and retrofitting X X X Ongoing
property/structures to prevent substantial flood
damage and provide technical information
8.1.5-Continue to update,distribute,and provide X X X Ongoing
flood protection information and materials
8.1.6-Maintain adequate flood insurance on public X Ongoing
structures
8.1.7-Provide floodplain information to property X Ongoing
and business owners,realtors,and prospective
buyers and encourage flood insurance
8.1.8-Maintain close liaison with nearby cities and X X X Ongoing
with County,State,and Federal agencies
8.1.9-Continue to participate in the National Flood X X_ Ongoing
Insurance Program and Community Rating System
52
C Y ^ C > N. O 'U N '
U - C C U
C LL ° M C Z
ccJ y m E m
0- m C N C ' o N
E E v U
a v v
a a
Goal Activity Responsible Department Schedule Status
8.1.10-Continue to implement the City's X Ongoing
emergency operation procedures as outlined in the
City's Emergency Management Plan,in particular,
the Flood Warning and Evacuation procedures
8.1.11 -Continue to utilize citizen volunteers,e.g., X Ongoing
CERT and RACES
8.1.12-Continue to provide a sandbag program X Ongoing
8.1.13—Encourage the State to modify the X X X Ongoing
roadway profile of Pacific Coast Highway
between Warner Avenue and Goldenwest Street
to prevent street closure due to flooding
U3-Storm 8.2.1 -Upgrade the City's flood control system X October 2020
Drainage (storm drains,catch basins,pump stations,and
channels)to current FEMA standards(100-year
flood)and concentrate on the repetitive flood areas
first
8.2.2-Quarterly the City Council shall lobby the X by January
County to correct,upgrade,and maintain the 2001 and
County's flood control system to current FEMA quarterly
standards(100-year flood) thereafter
8.2.3-Evaluate existing street conditions for X January 2010
replacement and/or installation of facilities to allow
proper conveyance of storm flows to the city's flood
control systems
8.2.4-Maintain the City's flood control system and X Ongoing
continue biannual inspection and cleaning of City's
flood control system
53
0) N C N d m N
C Y 1 C tl •C C V
c u. o t
�0 3 � ad = Ed
a _v m E c �. Ern
«_ V
IL a a v
Goal Activity Responsible Department Schedule Status
8.2.5-Update the City's Master Plan of Drainage to X October 2001
evaluate the effectiveness of the City's flood control
system
8.2.6-Lobby the federal,state and county X X X Ongoing
governments to study,pursue and expand the
wetlands from Beach Blvd.to Brookhurst St.for
floodwater mitigation
8.2.7-Evaluate and upgrade open areas,e.g., X Ongoing
Meadowlark Golf Course,Central Park,Good
Shepherd Cemetery to eliminate offsite drainage
and subsequent impact to private property.
8.2.8-Continue to support reconstruction of X Ongoing
deteriorating seawalls
8.2.9-Pursue funding from County,State and X X Ongoing
Federal agencies
8.2.10-Develop and support new funding sources X X X Ongoing
to help accomplish drainage goals
8.2.11 -Continue to participate in County X Ongoing
watershed studies and programs
EH5-Tsunami 8.3.1 -Update the Tsunami Emergency Operation X , Ongoing
plan,Operations Plan 2,as needed
8.3.2-Continue to provide tsunami warning to the X Ongoing
community
8.3.3-Educate the public regarding the potential X Ongoing
threat of a tsunami
54
o, W m 0 r N (Aa - r N)
C 'Y C CW7 C C 'C V
C p LL 'p d 10'� M 7 7.-
M 7 J y G> N V E N
FL V m CN .0 T GN _
Goal Activity Responsible Department Schedule Status
ERC2-Biological 8.4.1 -Implement best management practice plans X X Ongoing
Resources and National Pollution Discharge Elimination Plans
8.4.2-Investigate and install in-line wetlands in X Ongoing
drainage courses wherever feasible
8.4.3-Prohibit filling of wetlands except as allowed X Ongoing
by the General Plan
8.4.4—Encourage the State to maintain the coastal X Ongoing
dunes adjacent to the Bolsa Chica wetlands and in
the Huntington Beach wetlands to better protect the
areas from storm surges
8.4.5—Continue the Coastal Conservation District X Ongoing
zoning on the wetlands
EH2-Erosion 8.5.1 —Establish building setbacks from all slopes X October 2002
including mesa and bluff edges
8.5.2—Participate in the bluff(between Goldenwest X Ongoing
and Seapoint Streets)erosion study and implement
t recommendations
LU14-Open 8.6.1 -Limit construction in existing open space X X Ongoing
Space areas only to necessary structures such as
restrooms,picnic shelters
8.6.2—Evaluate the possibility of the City X Ongoing
purchasing surplus school sites to allow playfields
to remain as open areas and provide for floodwater
retention areas
55
I
C Y C _V C •C C 0C C LL 9 .« rd 1O �
J y m E m
EL u °° i=N c i. o cn
IL
v v U
a a
Goal Activity Responsible Department Schedule Status
HCR1 -Historical 8.7.1-Encourage property owners to floodproof X Ongoing
Resources historical structures
8.7.2-Encourage property owners of historical X Ongoing
structures to maintain adequate flood insurance
ti
56
SECTION 9.0
IMPLEMENTATION
9.0 IMPLEMENTATION
The Planning Department will maintain the Floodplain Management Plan. The
Planning Director will be responsible for ensuring the overall implementation of
the plan and for presenting an annual update to the Planning Commission and
City Council. The update will include an overview of the plan and the progress
made over the preceding 12 months to implement the recommendations listed in
Section 8.0.
57
SECTION 10.0
REFERENCES
10.0 REFERENCES
City of Huntington Beach Emergency Management Plan
City of Huntington Beach General Plan — adopted May 13,1996
County of Orange, Public Facilities and Resources Department
Flood Insurance Study for the City of Huntington Beach, Federal Emergency
Management Agency—August 16, 1982
Flood Insurance Study for the County of Orange and Incorporated Cities, Federal
Emergency Management Agency— 1989, 1992, 1995, 1997 editions
Flood Study, City of Huntington Beach Planning Department—April 1974
Geotechnical Inputs, City of Huntington Beach Planning Department— February
1974
National Flood Insurance Program
Seismic-Safety Element, City of Huntington Beach Planning Department—
October 1974
State of California Department of Parks and Recreation
State of California Department of Water Resources
Technical Background Report for the City of Huntington Beach General Plan
Update — July 2, 1992
The Orange County Register
US Army Corps of Engineers, Los Angeles District
58
SECTION 11 .0
GLOSSARY
11.0 GLOSSARY
100-year flood A flood having one percent chance of
being equaled or exceeded in any given
year (also called based flood).
Acre-feet A measurement of water volume. One
acre foot equals 325,851 gallons.
Catch basin An opening in the street adjacent to the
curb that allows water from the street to
flow into an underground drainage pipe.
Critical facility Facilities that either provide emergency
services or house and serve many people
who would be injured or killed in a case of
disaster damage to the facility, e.g.,
hospitals, emergency-service, utility
facilities, and communication.
Culvert A closed conduit for the passage of
stormwater under a highway, railroad, or
other embankment.
Detention basin An area used to decrease the peak flow
form a drainage area by storing a portion
of the runoff permanently.
Drainage area An area that uses a common storm drain
or channel system.
Erosion The process by which soil and rock are
detached and moved by running water,
wind, ice, and/or gravity.
Facilities Components of the storm drain system,
such as catch basins, pipes, manholes,
and channels.
Flood control channel An open conduit usually trapezoidal or
rectangular in shape used to move
extremely large amounts of water through
a drainage area.
59
Flood Insurance Rate Map (FIRM) The official map on which areas of special
flood hazard, the risk premium zones, and
the floodway applicable to the community
are delineated.
Flood or flooding A general and temporary condition of
partial or complete inundation of normally
dry land areas from the overflow of inland
or tidal waters; the unusual and rapid
accumulation of runoff of surface waters
from any source; mudslides; and
condition resulting from flood-related
erosion.
Floodplain Any land area susceptible to being
inundated by water from any source.
Gutter A paved surface adjacent to a curb for
draining water at the edge of a street or
road.
Infrastructure Facilities owned by the City that require
on-going maintenance and eventual
replacement.
Landslide A general term for a falling mass of soil or
rocks.
Levee A raised area bordering an irrigated area,
river or other body of water designed to
prevent water from overflowing.
Master Plan of Drainage An engineering report outlining the
drainage facilities needed for
improvement and the financing of the
proposed drainage systems by the land's
tributary to the given facility.
National Geodetic Vertical Datum A datum used to reference base flood
of 1929 (NGVD) elevations (also know as mean sea level).
Peak water flow The amount of water flow measured in
cubic feet per second.
60
Pump station A.building equipped with one or more
pumps designed to lift water from one
area to another.
Reservoir A body of water collected and stored for
future use in a natural or artificial lake or
structure.
Retention basin A depressed area of land designed by
nature or manmade to retain water for a
short period of time.
Sand dunes Naturally occurring accumulations of sand
in ridges or mounds landward of the
beach.
Special flood hazard area (SFHA) Land located in a floodplain within a
community subject to a one percent
chance of flooding in any given year (100-
year flood).
Storm drain An enclosed conduit (pipe) intended for
the reception and transfer of stormwater
through a drainage area.
Storm drainage system A system composed of pipes, catch
basins, gutters, channels, and pump
stations designed to transport stormwater
to a larger body of water e.g., lake, bay,
ocean.
Subsidence The gradual, local settling, or sinking of
the earth's surface with little or no
horizontal motion; usually the result of
gas, oil, or water extraction.
Tributary A storm drain and/or channel flowing into
a larger storm drain and/or channel..
Velocity The rate of water flow measured in feet
per second.
61
r
Wetland Lands which may be"_covered periodically
or permanently with 0hallow water-and
include saltwater marshes, freshwater
marshes, open or closed brackish water
marshes, swamps, mudflats, and fens.
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