Water Supply:
Fire fighters at the urban/wildland interface may be faced by limited water supply and lack of hydrant taps. Rural areas are characteristically outfitted with small-diameter pipe water systems, inadequate for providing sustained fire-fighting flows.
Areas at higher elevations may also be serviced by water that is pumped up to the higher elevations. In the event of a fire, there may be insufficient water pressure to do so. Emergency water storage is also critical, especially when battling large wildland fires. During the 1993 Laguna Beach (Orange County) fire, “water streams sprayed on burning houses sometimes fell to a trickle” (Orange County Fire Department, 1994), primarily because most water reservoirs in Laguna were located at lower elevations, and the water district could not supply water to the higher elevations as fast as the fire engines were Local Hazard Mitigation Plan Section 7: Wildfires
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using it. Leaks and breaks in the water distribution system, including leaking irrigation lines and open valves in destroyed homes also reduced the amount of water available to the fire fighters. A seven-day emergency storage supply is recommended, especially in areas likely to be impacted by fires after earthquakes, due to the anticipated damage to the main water distribution system as a result of ground failure due to fault rupture, liquefaction, or landsliding.
Interface Fire Education Programs and Enforcement:
Fire protection in urban/wildland interface areas relies more heavily on landowners taking measures personally to protect their properties. Property owners are more likely to take the initiative if they are informed of the risk. Therefore, public education and awareness should play a greater role in interface areas.
In those areas with strict fire codes, property owners who resist maintaining the minimum brush clearances on their property should be cited for failure to clear brush.
The Need for Mitigation Programs:
Continued development into the urban/wildland interface will have a growing impact on the wildfire risk of the area. Wildfires in southern California occur periodically, often with catastrophic results, with the history of deadly and expensive fires going back decades, if not a century. Continued growth and development underscore the increased need for natural hazards mitigation planning in southern California.
Fires After an Earthquake – The Threat of Urban Conflagration:
Although this section deals primarily with the hazard of wildfires, there is another type of fire hazard that needs to be addressed. Specifically, large fires following an earthquake in an urban region, although rare, have the potential to cause great losses. The two largest peace- time urban fires in history, the 1906 San Francisco and 1923 Tokyo, were both caused by earthquakes. The conflagration in San Francisco after the 1906 earthquake was the single largest urban fire, and the single largest earthquake loss, in U.S. history. Three days of fires consumed more than 28,000 buildings within a 12-square-kilometer area. The cost is Local Hazard Mitigation Plan Section 7: Wildfires
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staggering: $250 million in 1906 dollars, or about $5 billion at today’s prices. Although the threat that existed in San Francisco was and is far greater than that in Glendale today, there are some sections of Glendale where, due to ground failure as a result of either fault rupture or liquefaction, breaks in the gas mains and the water distribution system could lead to a significant fire-after-earthquake situation. Refer to the maps in Appendix H for information regarding those areas of the city susceptible to surface fault rupture and liquefaction.
The 1989 Loma Prieta earthquake, the 1994 Northridge earthquake, and the 1995 Kobe, Japan earthquake all demonstrate the current, real possibility of a fire-following-an earthquake developing into a conflagration. In the United States, all the elements that would hamper fire-fighting capabilities are present: density of wooden structures, limited personnel and equipment to address multiple fires, debris blocking the access of fire-fighting equipment, and a limited water supply.
Of the examples above, let’s look at the earthquake closest to home. The moderately sized, M6.7 Northridge earthquake of 1994 caused several structural fires, many the result of broken gas mains: the earthquake caused 15,021 natural gas leaks that resulted in three street fires, 51 structural fires (23 of these caused total ruin) and the destruction by fire of 172 mobile homes. In one incident, the earthquake severed a 22-inch gas transmission line and a motorist ignited the gas while attempting to restart his stalled vehicle. Response to this fire was impeded by the earthquake’s rupture of a water main; five nearby homes were destroyed. Elsewhere, one mobile home fire started when a downed power line ignited a r u p t u r e d t r a n s m i s s i o n l i n e . I n m a n y o f t he destroyed mobile homes, fires erupted when inadequate bracing allowed the homes to slip off their foundations, severing gas lines and igniting fires.
There was a much greater incidence of mobile home fires (49.1 per thousand) than other structure fires (1.1 per thousand).
The damages from the 1994 earthquake reminded researchers of the findings of a study published in 1988 by the California Division of Mines and Geology (Toppozada and others, 1988). This study identified projected damages in the Los Angeles area as a result of an Local Hazard Mitigation Plan Section 7: Wildfires
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earthquake on the Newport-Inglewood Fault. The earthquake scenario estimated that thousands of gas leaks would result from damage to pipelines, valves and service connections. This study prompted the Southern California Gas Company to start replacing their distribution pipelines with flexible plastic polyethylene pipe, and to develop ways to isolate and shut off sections of supply lines when breaks are severe. Nevertheless, as a result of the 1994 Northridge earthquake, the Southern California Gas Company reported 35 breaks in its natural gas transmission lines and 717 breaks in distribution lines. About 74 percent of its 752 leaks were corrosion related. Furthermore, in the aftermath of the earthquake, 122,886 gas meters were closed by customers or emergency personnel. Thankfully, most of the leaks were small and could be repaired at the time of service restoration, but the costs and time associated with these repairs were considerable.
History indicates that fires following an earthquake have the potential to severely tax the local fire suppression agencies and develop into a worst-case scenario. Earthquake-induced fires can place extraordinary demands on fire suppression resources because of multiple ignitions. The principal causes of earthquake-related fires are open flames, electrical malfunctions, gas leaks, and chemical spills. Downed power lines may ignite fires if the lines do not automatically de-energize. Unanchored gas heaters and water heaters are common problems, as these readily tip over during strong ground shaking (State law now requires new and replaced gas-fired water heaters to be attached to a wall or other support).
Many factors affect the severity of fires following an earthquake, including ignition sources, types and density of fuel, weather conditions, functionality of the water systems, and the ability of firefighters to suppress the fires. Casualties, debris and poor access can all limit fire-fighting effectiveness. Water availability in Los Angeles County following a major earthquake will most likely be curtailed due to damage to the water distribution system — broken water mains, damage to the aqueduct system, damage to above-ground reservoirs, etc.
Loss-estimation scenarios were conducted for the city of Glendale using HAZUS. Specifics of this analysis are discussed in detail in Section 6 – Earthquakes. Five different earthquake scenarios were considered for the city. The results of these loss estimations indicate that Local Hazard Mitigation Plan Section 7: Wildfires
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Glendale could experience between 3 and 11 ignitions immediately following an earthquake, with the San Andreas Fault earthquake scenario triggering 3 ignitions, and the Verdugo and Sierra Madre Faults triggering 11 ignitions each. The Raymond and Hollywood Faults are both expected to trigger 10 ignitions in the city. The burnt area resulting from these ignitions will vary depending on wind conditions.
Normal wind conditions of about 10 miles per hour (mph) are expected to result in burn areas of between 1.9 and 6.7 percent of the region’s total area. If Santa Ana wind conditions are present at the time of the earthquake, the burnt areas can be expected to be significantly larger.
The fires triggered by an earthquake on the San Andreas Fault are anticipated to displace as few as 30 people (if the winds are low), and as many as 308 people (if 30 mph winds are blowing through the area at the time). The fires triggered by the other earthquake scenarios are expected to impact between 116 and 354 people (if winds are low), and as many as 2,047 to 2,919 people (if 30 mph winds are present).
Wildfire Mitigation Activities:
Hazard mitigation programs in fire hazard areas currently include fire prevention, vegetation management, legislated construction requirements, and public awareness. Each of these programs is described further below.
Fire Prevention: Fire prevention aims to reduce the incidence and extent of fire by preventing wildfires from occurring in the first place. Over the years, a variety of fire prevention programs have been developed and implemented by Federal, State, and local agencies. These programs typically include education, engineering, patrolling, code enforcement, and signing (Greenlee and Sapsis, 1996). Smokey the Bear is one of the best- known characters that both children and adults recognize, attesting to the success of public education programs aimed at fire prevention. Quantitative studies show that fire losses arising from human fires, especially those caused by children, have dropped substantially over the last 30 years or so, in some cases by as much as 80 percent (Greenlee and Sapsis, 1996). Therefore, fire prevention is a well-understood program with a high degree of Local Hazard Mitigation Plan Section 7: Wildfires
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success. However, as discussed above, by preventing fire from occurring, fuel loads are allowed to increase, with the potential for high intensity fires and resultant damage. Therefore, fire prevention needs to be complemented with a variety of other programs that will guarantee long-term success in reducing the losses resulting from fires.
Fire Prevention can include limiting access to fire hazard areas during certain times of the year. Although not apparent from Map 7-2, the wildfire susceptibility of an area changes throughout the year, and from one year to the next, in response to local variations in precipitation, temperature, vegetation growth, and other conditions. When the fire danger in a High Fire Hazard Zone is deemed to be of special concern, local authorities can rely on increased media coverage and public announcements to educate the local population about being fire safe. For example, to reduce the potential for wildfires during fire season, the City of Glendale can opt to close hazardous fire areas to public access during at least part of the year. By monitoring site-specific wildfire susceptibility of a region, the Fire Department can establish regional prevention priorities that help reduce the risk of wildland fire ignition and spread and help improve the allocation of suppression forces and resources, which can lead to faster control of fires in areas of high concern.
Restricted public access to hiking trails in and around the city of Glendale during the fire season may help reduce the opportunity for human-caused wildfires in the area. Continued use of warning signs during high and extreme fire conditions along the freeways and roads that cut through the wildland areas in the city and adjacent areas can also help reduce the fire hazard by alerting and educating motorists and residents.
The City of Glendale has several wildfire mitigation programs in place including fire prevention, fire investigation and arson, vegetation management, legislated construction requirements, and public awareness. Routine (annual or bi-annual) fire prevention inspections are conducted on a citywide basis by the Fire Department for residential, commercial, and industrial-type occupancies. The Fire Prevention Bureau of the City’s Fire Department inspects all new and existing public assemblies, educational facilities, institutions and hospitals, high-rise buildings, hazardous materials occupancies, malls and large retail centers, and all new residential dwellings (Glendale Fire Department, 1994). The Local Hazard Mitigation Plan Section 7: Wildfires
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inspections are conducted to enforce the Fire Code and hazardous materials regulations, and for Fire Department personnel from within that jurisdictional area to become familiar with the premises (this is helpful in the event that they need to respond to a fire or emergency), and to instruct occupants about fire prevention methods and procedures. The Neighborhood Services Section of the Community Development Department provides assistance with the inspection of single-family residential dwellings as part of a community- wide beautification program. All personnel that conduct these surveys have received training in hazard recognition from the Fire Department.
In addition to these requirements, the City has been involved in legislated construction requirements in fire hazard areas such as roof coverings, fire doors, and fire-resistant materials that help protect structures from external fires. Most recently the City has adopted the 2017 Building & Safety Codes with local additions and amendments dealing with new construction requirements in fire hazard areas.
Glendale’s Fire Prevention Bureau is comprised of several different units, each with specific responsibilities. Fire Prevention Bureau members have the powers of a peace officer in enforcing the City’s Fire Code. The responsibilities of each unit are described further below:
x Fire Code Inspection – conducts inspections of all new and existing structures. x Development Plan Review – reviews proposed developments for conformance with fire protection requirements including fire-resistive construction, landscaping, emergency access, available fire flow, and built-in fire detection and suppression systems.
x Fire Investigation and Arson – investigates fire cause and origin, administers aggressive code enforcement, and analyzes cost recovery for negligent or malicious acts causing fire. All members of this unit have full police powers as set in California Penal Code Section 832 (Section 103.2.2.3 of the City’s Building and Safety Code). x Vegetation Management – reviews existing properties for compliance with fuel management requirements; administers and enforces the weed abatement and brush clearance program, and contracts for fire hazard reduction measures, including fuel breaks, fire roads, and non-compliant parcels.
x Hazardous Materials and Waste Management – administers hazardous materials disclosure laws and legislation, as well as conducts inspection of underground storage tanks and facilities that use or store hazardous materials for environmental compliance.
x Public Education – provides public fire safety education for groups or individuals on the hazards associated with the urban-wildland interface area.
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The Glendale Fire Department has several outreach programs aimed in providing fire safety education to the public such as fire prevention week, which promotes specific community- based demonstration projects of fire prevention and mitigation in the urban areas interface.
Vegetation Management: Although, as discussed above, wildland fire is a significant potential hazard in large portions of Glendale, there are several management tools that can be implemented to reduce this hazard to manageable levels. Experience and research have shown that vegetation management is an effective means of reducing the wildland fire hazard in southern California. As a result, in areas identified as susceptible to wildland fire, jurisdictions typically require property owners to use a combination of maintenance approaches aimed at reducing the amount and continuity of the fuel (vegetation) available.
Fuel or vegetation treatments often used include mechanical, chemical, biological and other forms of biomass removal (Greenlee and Sapsis, 1996) or hazard reduction within a given distance from habitable structures. The intent is to create a defensible space that slows the rate and intensity of the advancing fire and provides an area at the urban-wildland interface where firefighters can set up to suppress the fire and save the threatened structures.
Defensible space is defined as an area, either natural or man-made, where plant materials and natural fuels have been treated, cleared, or modified. However, removal of the native vegetation and maintenance of a wide strip of bare ground is not aesthetically acceptable and it increases the potential for water runoff and soil erosion. Native vegetation can be replaced with a green belt of low-lying, vegetation, but the increased use of water and maintenance requirements can make this option undesirable.
Another approach used in some areas of southern California is referred to as fuel modification. This method places emphasis on the space near structures that provides natural landscape compatibility with wildlife, water conservation and ecosystem health. Immediate benefits of this approach include improved aesthetics, increased health of large remaining trees and other valued plants, and enhanced wildlife habitat.
The City of Glendale uses fuel modification to reduce its wildfire hazard. Specifically, in 1993, the City of Glendale adopted a Hillside Development Plan that provides guidelines regarding Local Hazard Mitigation Plan Section 7: Wildfires
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landscaping and vegetation modification to promote fire safety while protecting the visual quality of the hillsides (City of Glendale, 1993). The landscape guidelines provide lists of plants (referred to as plant palettes) that are drought tolerant and help control erosion to be used on engineered slopes. By using these plants instead of non-native species, the visual contrast between the natural hillsides and the engineered slopes can be diminished, making the man-made slopes resemble more closely the adjacent natural slopes. Two plant palettes are available: the naturalizing palette, which includes plants to be used on that portion of the engineered slopes closer to the natural hillsides; and the ornamental palette, to be used on that section of the slope closer to structures, adjacent to the ornamental vegetation. On large enough slopes, both plant palettes can be blended along a 150-foot wide interface. For the most recent version of the plant palettes acceptable in Glendale, a copy may be requested from the City’s Planning Department.
The Fire Zone Management Guidelines portion (Section 8.0) of Glendale’s Landscape Guidelines Plan outlines the methods by which the two plant palettes discussed above are to be used around all flammable structures in the wildland urban interface. A minimum buffer distance of 100 feet is required around all structures; in some cases, at the discretion of the City’s Fire Chief, this buffer distance may be increased to 200 feet. Within this buffer distance, the City requires four distinct Fire Management Zones to be established. Each of these zones is described further below and shown graphically on Figure 1-1. x Zone 1: Zone 1 includes the natural, ungraded slope and continues to the edge of the engineered slope. Existing vegetation in this zone needs to be thinned selectively to reduce the fuel volume and lower the intensity of any fire that may approach buildings. Foliage mass reduction is accomplished by removing large shrubby plants and dense groupings. The thinning of these plants needs to be conducted in such a way as to create a natural appearance and not expose excess soil areas that would then be susceptible to erosion.
x Zone 2: Zone 2 is the next zone inward from the natural, ungraded terrain, where low, slow-burning plantings should predominate. The volume of vegetation in this zone needs to be reduced and replaced with fire-resistant plant materials from both the naturalizing and ornamental plant palettes. Their low growth and limited foliage mass can diminish the intensity of wildfires and prevent erosion of the slope. x Zone 3: This zone can vary between 20 and 25 feet in width, depending upon the degree of fire risk in the area, and consists of fire-retardant plantings. This zone is referred to as the fire buffer zone or maximum fire prevention edge and includes Local Hazard Mitigation Plan Section 7: Wildfires
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plants from both the ornamental and naturalizing palettes that require regular irrigation and weed control. Although some drought tolerant plants may be acceptable in this area, higher water and maintenance demands actually help achieve the maximum fire barrier. The plants in this zone are typically ground covers and plants with low fuel volumes.
x Zone 4: This zone is the area immediately surrounding the structure where ornamental plantings are preferred. The pla n t s i n t h i s z o n e s h o u l d b e c a r e f u l l y selected and placed. The number of tall trees should be limited. Foliage should be thinned, and dead branches and vegetation removed from those areas next to the building.
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Figure 7-3: Glendale’s Hillside Planting Zones
(From the City of Glendale Landscape Guidelines for Hillside Development) These standards require property owners in fire hazard areas, especially at the wildland urban interface, to conduct maintenance, modifying or removing non-fire-resistive vegetation around their structures to reduce the fire danger. This affects any person who owns, leases, controls, operates, or maintains a building or structure in, upon, or adjoining the WUI area. Other specific maintenance actions that can be undertaken by property owners in the fire hazard areas include:
xRemove all dead vegetation and keep grasses and weeds maintained within 100 feet of any building and within 10 feet of any roadway. These provisions are part of an amendment to the Hazardous Vegetation Ordinance adopted in 1990. In extreme cases, clearance up to 200 feet from a structure and 50 feet from a roadway may be required by the Fire Department.
xGrasses and other vegetation located more than 30 feet from any building and less than 18 inches in height may be maintained where necessary to prevent erosion. Large trees and shrubs in that area should be at least 18 feet apart. xRemove leafy foliage, dead wood, combustible ground cover, twigs, or branches within 3 feet of the ground from mature trees located within 100 feet of any building or within 10 feet of any roadway.
xRemove dead limbs, branches, and other combustible matter from trees or other growing vegetation adjacent to or overhanging any structure.
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x Remove any portion of a tree that extends within 10 feet of a chimney or stovepipe. x Trim and maintain all vegetation away from the curb line up to a height of 13.5 feet to accommodate emergency vehicles.
x Maintain 5 feet vertical clearance between roof surfaces and any overhanging portions of trees.
x Property owners in the wildland urban interface area can request that the Fire Department conduct a comprehensive fire safety survey of their homes and property. The Fire Department inspects the residences for compliance with applicable regulations and prepares a report for use by the homeowner to reduce its fire hazard. Implementation of the recommended mitigation measures may help the homeowner obtain a reduction in the cost of fire insurance.
It is the philosophy of the Glendale Fire Department to prevent catastrophic brush fires through comprehensive code enforcement efforts and, when necessary, a rapid response of properly trained and equipped firefighters. Successfully preventing fires requires a partnership between the community and the Glendale Fire Department to maintain the hill areas free of hazardous brush and combustible vegetation.
Prescribed Fire: As discussed previously, before modern settlement began, the area experienced small but frequent wildfires that impacted primarily the grasses and low-lying bushes, without severely damaging the tree stands. As man-made structures were built in these fire-susceptible areas, there was a strong effort to suppress fires, since these would threaten the structures and people living there. As a result, dense stands of vegetation have accumulated locally in the outlying areas, while increasingly larger numbers of people have moved into the -wildland urban interface. Over time, fire suppression and increasing populations have produced these results:
x Increased losses to life, property, and resources.
x Difficulty of fire suppression, increased safety problems for firefighters, and reduced productivity by fire crews on perimeter lines.
x Longer periods between recurring fires for many vegetation types by a factor of 5 or more.
x Increased volume of fuel per acre.
x Increased fire intensities.
x Increased taxpayer costs and property losses.
Recognition of these problems has led to vegetation management programs such as those described above, and in some areas, prescribed fires. A prescribed fire is deliberately set Local Hazard Mitigation Plan Section 7: Wildfires
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under carefully controlled and monitored conditions. The purpose is to remove brush and other undergrowth that can fuel uncontrolled fires. Prescribed fire is used to alter, maintain or restore vegetative communities, achieve desired resource conditions, and to protect life and property that would be degraded by wildland fire. Prescribed fire is only accomplished through managed ignition and should be supported by planning documents and appropriate environmental analyses.
Since 1981, prescribed fire has been the primary means of fuel management in Federal and State-owned lands. Approximately 500,000 acres — an average of 30,000 acres a year — have been treated with prescribed fire under the vegetation management program throughout the State. In the past, the typical vegetation management project targeted large wildland areas. Now, increasing development pressures (with increased populations) at the wildland urban interface often preclude the use of large prescribed fires. Many still find the notion of “prescribed fire” difficult to accept since for the last 100 years or so, humans have attempted to suppress and fight fires. Prescribed fire also carries a risk, as recent experiences in New Mexico and Arizona have shown. The Cerro Grande fire began when a prescribed burn escaped, destroying several hundred homes in Los Alamos, New Mexico and burning more than 50,000 acres. It is likely that this fire will lead to revisions in the guidelines for performing prescribed burns. Furthermore, a recent program review by the CDF has identified needed changes, with focus on citizen and firefighter safety, and the creation of wildfire safety and protection zones.
Prescribed fire is not presently being used in the City of Glendale to mitigate the wildland fire hazard. However, the cities of Glendale and La Canada Flintridge have entered into a cooperative agreement with Los Angeles County Fire Department to conduct prescribed fires in the Descanso Gardens area. This effort will include open space areas within the City of Glendale at the north end of the San Rafael Hills. The proposed plan has been approved by all parties involved and is ready to be implemented as soon as all conditions for a safe prescribed fire are met.
Hazard Abatement Notices: Each spring, the Glendale Fire Department mails information and hazard brush pamphlets to approximately 4,500 residences located in designated High Local Hazard Mitigation Plan Section 7: Wildfires
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Fire Hazard Areas. The purpose of this mailing is to remind and inform property owners of their specific responsibility to mitigate hazardous vegetation conditions. The mailing is followed-up, commencing May 1, by Fire Department fire company inspections of residences and lots to ensure compliance. Fire department personnel are assigned inspection districts throughout the City. Fire Department personnel survey the hillside areas and issue notices of violation for hazardous vegetation on an annual basis. If abatement work is not completed in a timely manner, a “Notice to Abate Fire Hazard” is sent and a compliance inspection is conducted 30 days later. If abatement is still not satisfactory a “Notice of Intention to Abate Public Nuisance” is sent, and a final inspection made after 15 days to ensure compliance. If voluntary compliance is not achieved, the Fire Department may abate the hazardous vegetation using an approved contractor and charge the owner or impose a lien on the property.
At this time, per an agreement between Glendale and the County of Los Angeles, the Los Angeles County Agricultural Commissioner provides for weed abatement on non-compliant improved properties and approximately 800 vacant lots in the City of Glendale.
Legislated Construction Requirements in Fire Hazard Areas: Building construction standards for such items as roof coverings, fire doors, and fire-resistant materials help protect structures from external fires and contain internal fires for longer periods. That portion of a structure most susceptible to ignition from a wildland fire is the roof, due to the deposition of burning cinders or brands. Burning brands are often deposited far in advance of the actual fire by winds. Roofs can also be ignited by direct contact with burning trees and large shrubs (Fisher, 1995). The danger of combustible wood roofs, such as wooden shingles and shakes, has been known to firefighting professionals since 1923, when California’s first major urban fire disaster occurred in Berkeley. It was not until 1988, however, that California was able to pass legislation calling for, at a minimum, Class C roofing in fire hazard areas. Then, in the early 1990s, there were several other major fires, including the Paint fire of 1990 in Santa Barbara, the 1991 Tunnel fire in Oakland/Berkeley, and the 1993 Laguna Beach fire, whose severe losses were attributed in great measure to the large percentage of Local Hazard Mitigation Plan Section 7: Wildfires
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combustible roofs in the affected areas. In 1995-1996 new roofing materials standards were approved by the California legislature for Very High Fire Hazard Severity Zones.
Significantly, the City of Glendale has been at the forefront of the State on this issue since the early 1980s. Specifically, in 1984, Glendale adopted a Fire Safe Roofing Ordinance that required a minimum Class B roof covering for all new and re-roofs applications City-wide. In 1989, Glendale adopted legislation (the Fire Safe Roofing Code) that amended the City’s roofing requirements to ban the installation of wood roof material City-wide, and to upgrade the minimum classification from B to A in the h i g h f i r e h a z a r d a r e a s . T o d a y , G l e n d a l e requires all new roofs and re-roofs amounting to more than 25 percent of the original roof area to be done in Class A roof covering.
So, what do these Classes A, B and C mean? To help consumers determine the fire resistance of the roofing materials they may be considering, roofing materials are rated as to their fire resistance into three categories that are based on the results of test fire conditions that these materials are subjected to under rigorous laboratory conditions, in accordance with test method ASTM-E-108 developed by the American Society of Testing Materials. The rating classification provides information regarding the capacity of the roofing material to resist a fire that develops outside the building on which the roofing material is installed (The Institute for Local Self Government, 1992). The three ratings are as follows:
Class A: Roof coverings that are effective against severe fire exposures. Under such exposures, roof coverings of this class:
x Are not readily flammable;
x Afford a high degree of fire protection to the roof deck; x Do not slip from position; and
x Do not produce flying brands.
Class B: Roof coverings that are effective against moderate fire exposures. Under such exposures, roof coverings of this class:
x Are not readily flammable;
x Afford a moderate degree of fire protection to the roof deck; x Do not slip from position; and
x Do not produce flying brands.
Class C: Roof coverings that are effective against light fire exposures. Under such exposures, roof coverings of this class:
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x Are not readily flammable;
x Afford a measurable degree of fire protection to the roof deck; x Do not slip from position; and
x Do not produce flying brands.
Non-Rated Roof coverings have not been tested for protection against fire exposure. Under such exposures, non-rated roof coverings:
x May be readily flammable;
x May offer little or no protection to the roof deck, allowing fire to penetrate attic space and the entire building; and
x May pose a serious fire brand hazard, producing brands that could ignite other structures a considerable distance away.
Attic ventilation openings are also a concern regarding the fire survivability of a structure. Attics require significant amounts of cross-ventilation to prevent the degradation of wood rafters and ceiling joists. This ventilation is typically provided by openings to the outside of the structure, but these openings can provide pathways for burning brands and flames to be deposited within the attic. Therefore, it is important that all ventilation openings be properly screened to prevent this. Additional prevention measures that can be taken to reduce the potential for ignition of attic spaces are to “use non-combustible exterior siding materials and to site trees and shrubs far enough away from the walls of the house to prevent flame travel into the attic even if a tree or shrub does torch” (Fisher, 1995).
The type of exterior wall construction used can also help a structure survive a fire. Ideally, e x t e r i o r w a l l s s h o u l d b e m a d e o f n o n - c o m b u s t i b l e m a t e r i a l s s u c h a s s t u c c o o r masonry. During a wildfire, the dangerous active burning at a given location typically lasts about 5 to 10 minutes (Fisher, 1995), so if the exterior walls are made of non-combustible or fire-resistant materials, the structure has a better chance of surviving. For the same reason, the type of windows used in a structure can also help reduce the potential for fire to impact a structure. Single-pane, annealed glass windows are known for not performing well during fires; thermal radiation and direct contact with flames cause these windows to break because the glass under the window frame is protected and remains cooler than the glass in the center of the window. This differential thermal expansion of the glass causes the window to break. Larger windows are more susceptible to fracturing when exposed to high heat than smaller windows. Multiple-pane windows, and tempered glass windows perform much Local Hazard Mitigation Plan Section 7: Wildfires
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better than single-pane windows, although they do cost more. Fisher (1995) indicates that in Australia, researchers have noticed that the use of metal screens helps protect windows from thermal radiation. Some homeowners may consider the use of exterior, heavy-duty metal blinds that are dropped down into position, at least on the windows in the exposed portion of the structure facing the wildland area.
Fire sprinklers are very effective at controlling structural fires, saving property and lives. In 1988, Glendale passed an ordinance requiring automatic fire sprinklers in existing structures four stories or more in height, and since 1989, the City of Glendale has required all new one- and two-family structures to have fire sprinklers. Fire sprinklers can help contain a fire that starts inside a structure from becoming a potential incendiary source, impacting other nearby structures and brush. Fire sprinklers are not likely to protect a structure from an external wildland fire, however. Sprinklers permanently mounted on the roof have been suggested as a defensive measure, but most authorities argue against the value of external sprinklers as a viable alternative to fire-resistant roofing materials (http://www.fs.fed.us/psw/publications/documents/gtr-050/struct.html).
The City of Glendale has adopted the California Building and Fire Codes with local additions and amendments (City Ordinance 5329 - Glendale Building and Safety Code, Volume I, Section 715 which deals with construction requirements in fire hazard areas, and Volume VI, which pertains to fire and life-safety requirements). These additions and amendments make the Glendale Building and Safety Code more restrictive than the minimum State Code / model ordinance. For specific requirements regarding roofing standards (non-combustible Class A roofs), construction materials and standards including fire resistive siding and eaves, the orientation and placement of window glazing, sprinklers, etc., contact the Fire Prevention Bureau and Building Section of the City of Glendale.
Public Awareness: Individuals can make an enormous contribution to fire hazard reduction and need to be educated about their important role. The Glendale Fire Department has several outreach programs aimed at providing fire safety education to the public. These presentations are given to local schools, service clubs and associations, homeowners groups, the Chamber of Commerce, Board of Realtors, businesses and other professional Local Hazard Mitigation Plan Section 7: Wildfires
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organizations. The Jr. Fire Program, which is more than 50 years old, sends firefighters into all of the 5th grade classes in the area to teach fire safety and awareness. A picnic at the end o f t h e s c h o o l y e a r i s h e l d t o h o n o r t h o se students that demonstrated exceptional participation in the program. Every October, the Fire Department also contracts with a theater group to present fire safety programs to all elementary schools in Glendale.
One of the most recent public education tools used by the Fire Department is the Fire Safety Trailer, which is operated in conjunction with the Burbank and Pasadena Fire Departments. The trailer provides a scaled version of a house, where children can learn and practice life-saving procedures. These and many other public education and outreach programs that the Fire Department offers are described in the Fire Department’s effective website (https://www.glendaleca.gov/government/departments/fire-department). This web site is also an education tool that residents can refer to for additional information regarding how to deal with fire and other natural and man-made hazards.
The Fire Department has also prepared and distributes informational brochures to hillside property owners. The brochures describe mitigation measures that can be implemented to reduce the fire hazard and describe how property owners can help themselves to prevent loss of property or life as a result of a wildland fire. In addition to the specific requirements in the Municipal Code mentioned in the sections above regarding appropriate landscaping and construction materials, there are other steps that homeowners can take to reduce the risk of fire on their property.
Some of these are listed below. This list is not all-inclusive, but provides a starting point and framework to work from:
x Mow and irrigate your lawn regularly.
x Dispose of cuttings and debris promptly, according to local regulations. x Store firewood away from the house.
x Be sure the irrigation system is well maintained.
x Use care when refueling garden equipment and provide regular maintenance for your garden equipment.
x Store and use flammable liquids properly.
x Dispose of smoking materials carefully.
x Do not light fireworks (in accordance with the Municipal Code).
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x Become familiar with local regulations regarding vegetation clearing, disposal of debris, and fire safety requirements for equipment.
x Follow manufacturers’ instructions when using fertilizers and pesticides. x Keep the gutters, eaves, and roof clear of leaves and other debris. x Occasionally inspect your home, looking for deterioration, such as breaks and spaces between roof tiles, warping wood, or cracks and crevices in the structure. x Use non-flammable metal when constructing a trellis and cover it with high-moisture, non-flammable vegetation.
x Install automatic seismic shut-off valves for the main gas line to your house. Information for approved devices, as well as installation procedures, is available from the Southern California Gas Company.
Other Mitigation Programs and Activities:
Firewise: This is a program developed within the National Wildland/ Urban Interface Fire Protection Program and it is the primary federal program addressing interface fire. It is administered through the National Wildfire Coordinating Group whose extensive list of participants includes a wide range of federal agencies. The program is intended to empower planners and decision makers at the local level. Through conferences and information dissemination, Firewise increases support for interface wildfire mitigation by educating professionals and the general public about hazard evaluation and policy implementation techniques. Firewise offers online wildfire protection information and checklists, as well as listings of other publications, videos and conferences.
The interactive home page allows users to ask fire protection experts questions and to register for new information as it becomes available.
FireFree Program: This is a unique private/public program for interface wildfire mitigation involving partnerships between an insurance company and local government agencies. It is an example of an effective non-regulatory approach to hazard mitigation.
Originating in Bend, Oregon, the program was developed in response to the city's "Skeleton Fire" of 1996, which burned over 17,000 acres and damaged or destroyed 30 homes and structures. Bend sought to create a new kind of public education initiative that emphasized local involvement. SAFECO Insurance Corporation was a willing collaborator in this effort. Bend's pilot program included:
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x A short video production featuring local citizens as actors, made available at local video stores, libraries and fire stations;
x Two city-wide yard debris removal events;
x A 30-minute program on a model FireFree home, aired on a local cable television station; and
x Distribution of brochures, featuring a property owner evaluation checklist and a listing of fire-resistant indigenous plants.
Wildfire Mitigation Action Items
As stated in the Federal Wildland Fire Policy, “The problem is not one of finding new solutions to an old problem but of implementing known solutions. Deferred decision making is as much a problem as the fires themselves. If history is to serve us in the resolution of the wildland/urban interface problem, we must act on these issues now. To do anything less is to guarantee another review process in the aftermath of future catastrophic fires.
The wildfire mitigation action items below provide direction on specific activities that organizations and residents of southern California, including Glendale, can undertake to reduce risk and prevent loss from wildfire events. Each action item is followed by ideas for implementation, which can be used by the steering committee and local decision makers in pursuing strategies for implementation.
Short Term –Wildfire #1: Enhance emergency services to increase the efficiency of wildfire response and recovery activities.
Ideas for Implementation:
x Continue to develop Fire Watch programs and increase reporting stations/communications equipment (such as additional fire reporting phone lines) for better access and coverage.
x Continue to develop and increase training and outreach programs. x Enhance internal and external notification systems that include all at-risk wildland urban interface residents in the jurisdiction in order to contact them during evacuations.
Coordinating Organization: Glendale Fire Department and Glendale Water and Power (GWP)
Timeline: 2 y e a r s
Plan Goals Addressed: Emergency Services
Constraints: Pending funding and available personnel Local Hazard Mitigation Plan Section 7: Wildfires
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Short Term –Wildfire #2: Educate agency personnel on federal cost-share and grant programs, Fire Protection Agreements and other related federal programs so the full array of assistance available to local agencies is understood.
Ideas for Implementation:
x Investigate potential funding opportunities for individual mitigation projects; and x Develop, approve and promote Fire Protection Agreements and partnerships to clarify roles and responsibilities and to provide for fire mitigation activities and suppression preparedness.
Coordinating Organization: Glendale Fire Department
Timeline: 1-2 years
Plan Goals Addressed: Protect Life and Property, Public Awareness Constraints: Pending funding and available personnel Short Term – Wildfire #3: Inventory alternative firefighting water sources and encourage the development of additional sources.
Ideas for Implementation:
x Advocate for water storage facilities with fire-resistant electrical pump systems in developments outside of fire protection districts that are not connected to a community water or hydrant system; and
x Develop a protocol for fire jurisdictions and water districts to communicate all hydrant outages and water shortage information.
Coordinating Organization: City of Glendale Departments of Fire, Planning and GIS Timeline: 1 year
Plan Goals Addressed: Protect Life and Property
Constraints: Pending funding and available personnel Long Term –Wildfire #1: Encourage development and dissemination of maps relating to the fire hazard to help educate and assist builders and homeowners in being engaged in wildfire mitigation activities and to help guide emergency services during response.
Ideas for Implementation:
x Update wildland/urban interface maps.
x Conduct risk analysis incorporating data and the created hazard maps using GIS technology to identify risk sites and further assist in prioritizing mitigation activities; x Encourage coordination between fire jurisdictions and sanitary districts to make sure that the most accurate elevation maps are being used.
Coordinating Organization: City of Glendale Departments of Fire and Public Works Timeline: 1-3 years
Plan Goals Addressed: Protect Life and Property
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Constraints: Pending funding and available personnel Long Term – Wildfire #2: Enhance outreach and education programs aimed at mitigating wildfire hazards and reducing or preventing the exposure of citizens, public agencies, private property owners and businesses to natural hazards.
Ideas for Implementation:
x Continue the hiring of fire prevention and education personnel to oversee education programs;
x Continue to train in all areas of fire prevention;
x Visit urban interface neighborhoods and rural areas and conduct education and outreach activities;
x Conduct specific community-based demonstration projects of fire prevention and mitigation in the urban interface;
x Establish neighborhood "drive-through" activities that pinpoint site-specific mitigation activities. Fire crews can give property owners personal suggestions and assistance; and
x Perform public outreach and information activities at fire stations by creating "Wildfire Awareness Week" activities, Fire stations can hold open houses and allow the public to visit, see the equipment and discuss wildfire mitigation with the station crews.
Coordinating Organization: Glendale Fire Department
Timeline: Ongoing
Plan Goals Addressed: Protect Life and Property, Public Awareness Constraints: Pending funding and available personnel Long Term – Wildfire #3: Increase communication, coordination and collaboration between wildland/urban interface property owners, local and county planners and fire prevention crews and officials to address risks, existing mitigation measures and federal assistance programs.
Ideas for Implementation:
x Encourage single-family residences to have fire plans and practice evacuation routes; x Encourage fire inspections in residential homes by fire departments to increase awareness among homeowners and potential fire responders; x Encourage a standard for the State Fire Marshal to evaluate fire plans and emergency plans;
x Require fire department notification of new business applications to ensure that appropriate fire plans have been developed;
x Encourage local zoning and planning entities to work closely with landowners and/or developers who choose to build in the wildland/urban interface to identify and mitigate conditions that aggravate wildland/urban interface wildfire hazards, including:
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o Limited access for emergency equipment due to width and grade of roadways; o Inadequate water supplies and the spacing, consistency and species of vegetation around structures;
o Inadequate fuel breaks, or lack of defensible space;
o Highly flammable construction materials;
o Building lots and subdivisions that are not in compliance with state and local land use and fire protection regulations;
o Inadequate entry/escape routes;
o Encourage all new homes and major remodels involving roofs additions that are located in the interface to have fire resistant roofs and residential sprinkler systems; and
o Encourage the public to evaluate access routes to rural homes for fire-fighting vehicles and to develop passable routes if they do not exist.
Coordinating Organization: City of Glendale Departments of Community Development, Information Services, Public Works, and
Fire.
Timeline: Ongoing
Plan Goals Addressed: Protect Life and Property, Public Awareness, Emergency Services, Partnerships and Implementation
Constraints: Pending funding and available personnel Long Term – Wildfire #4: Encourage implementation of wildfire mitigation activities in a manner consistent with the goals of promoting sustainable ecological management and community stability.
Ideas for Implementation:
x Employ mechanical thinning to abate the risk of catastrophic fire and restore the more natural regime of high frequency, low-intensity burns. Prescribed burning can provide benefit to ecosystems by thinning hazardous vegetation and restoring ecological diversity to areas homogenized by invasive plants; x Clear trimmings, trees, brush and other debris completely from sites when performing routine maintenance and landscaping to reduce fire risk; and x Enhance programs to coordinate and monitor adjacent areas who utilize prescribed burning techniques.
Coordinating Organization: Glendale Fire Department
Timeline: Ongoing
Plan Goals Addressed: Natural Systems
Constraints: Pending funding and available personnel Local Hazard Mitigation Plan Section 7: Wildfires
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Glendale Water & Power Wildfire Mitigation Plan
The City of Glendale’s Water & Power department (GWP), recognizes the importance of developing a wildfire mitigation plan (Plan) to protect City customers, employees, and assets against the potential dangers and costs of damage incurred as a result of wildfires.
Two California Senate Bills SB-1028 and SB-901 were signed into law to strengthen wildfire mitigation through oversight of public utilities under the jurisdiction of the California Public Utilities Commission (CPUC). Although the City of Glendale does not fall under the authority of the CPUC, some of the requirements that are stated in these Senate Bills apply to the City. This document outlines the City’s approach to proactively preparing to comply with these requirements.
Compliance
The GWP General Manager or his delegate shall administer the Plan to monitor and audit the implementation of the Plan. The Plan shall be updated, reviewed, and approved by the General Manager of GWP on an annual basis. This annual review shall ensure that the Plan is updated to comply with all state regulations and City regulations and requirements. The General Manager may elect to summarize and review the Plan with the City Manager and/or present updates to the GWP Commission and/or City Council and obtain required approvals.
Implementation
As prescribed by the Plan, GWP staff shall engineer, construct, maintain, and operate its electric transmission and distribution system in a manner intended to minimize the likelihood of catastrophic wildfires posed by electrical lines and equipment. In developing the Plan, staff shall incorporate the following elements:
x Stakeholders- Staff shall develop a list of City personnel (comprised primarily of GWP staff) who are responsible for maintaining, updating, approving, and executing the Plan. This may include the following GWP personnel:
o General Manager
o Electrical Services Administrator
o Integrated Resources Planning Administrator
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o Electrical Superintendent(s)
o Electrical Line Mechanic Superintendent(s)
o Electrical Engineer(s)
o Independent Third-Party Evaluator
o Representatives from Glendale Fire Department (GFD)
o Other technical and field personnel necessary to implement the Plan x Objective- The Plan shall include a simply-worded objective to frame the purpose and goal of the Plan – for example, to engineer, construct, maintain, and operate its electric transmission and distribution system in a manner intended to minimize the risk of catastrophic wildfire posed by electrical lines and equipment. x Wildfire Zones- GWP staff shall work with Fire personnel to assign a tiered or ranked score for each system asset, possibly by grouping assets into geographic zones that are then evaluated and ranked by risk. This assessment shall be completed for all assets or zones within the City’s service territory. Each tier shall be assigned a commensurate level of mitigation effort, in which assets assigned to a “high” tier danger level shall receive a greater amount of resources to mitigate against fire danger, and assets assigned to a “low” tier danger level shall receive a lower amount of resources to mitigate against fire danger. In this way, the City can prioritize its resources to focus on preventing and mitigating wildfire danger in those areas where the fire danger is greatest. This exercise, then, shall drive funding priorities and operational philosophies.
x Capital Projects- Once the zones and assets have been categorized, GWP staff shall tailor its capital project plan to upgrade, enhance, and reinforce its electrical infrastructure to minimize the risk of its electrical system causing catastrophic wildfires. These projects shall prioritize “high” danger zones and may include replacing wood poles with steel or concrete poles, using sheathed cables to prevent arcing during wildfires, and leveraging and incorporating technological solutions to maintain service to customers during periods of high wildfire danger. x Operations & Maintenance (O&M) Efforts- Coupled with the capital projects to strengthen facilities and assets against wildfire risks, staff shall also initiate contracts to address non-capital efforts. Examples may include additional tree-trimming or brush-clearing efforts to reduce fuel levels in “high” danger zones. x Operational Practices- Engineering and field personnel shall conduct a thorough review of operational practices to identify preventative strategies and enhanced operational procedures to minimize and mitigate the risk of causing catastrophic wildfires, both during periods of high danger as well as during normal operating conditions. These practices shall meet or exceed industry best practices, which shall b e d e t e r m i n e d b a s e d u p o n c o m p a r i s o n t o l ocal utilities – for example, Southern
California Public Power Authority (SCPPA) utilities. This review may include an analysis of protocols for disabling automatic reclosers and de-energizing lines, understanding that these revised actions could have a detrimental impact on fire and police response, the availability of water, hospitals, schools, evacuation centers, and other critical facilities. The analysis may also include identification of high-risk transmission and distribution lines and equipment that should be de-energized during periods of extreme fire danger.
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x Staffing Levels- With increased Capital and O&M expenses, staff shall analyze staffing levels and determine whether additional permanent staff is necessary to implement and maintain the contents of this Plan on an on-going basis. x Energy Supply Contingencies. The City serves much of its electrical load through energy imported via high-voltage transmission lines that are owned in part by Glendale but operated by the Los Angeles Department of Water & Power (LADWP), Southern California Edison (SCE), and other utilities. Should these utilities elect to de-energize these transmission lines during periods of extreme fire danger (which usually correlate with periods of high electrical loads), the City would be forced to procure replacement energy from alternate energy sources. These alternate energy sources are scarce and may not be available: when the City experiences periods of high electrical load, so do the other utilities, whose first priority is to maintain sufficient energy and reserves to meet their own load and obligations. x High Fire-Danger Mode- GWP may leverage alternative operating practices, more conservative in nature, once it has been determined that a high fire danger period has begun. GWP shall elect to early communicate to its staff, and possibly to City personnel and customers, when GWP equipment and facilities should be operated in a “high wildfire danger” mode. This mode, or set of modes, shall direct staff to take additional, or distinct, precautions during times of extreme wildfire danger. This should be triggered by a standard protocol – for example, when LADWP issues a restricted maintenance directive due to extreme heat, or when the United States Department of Agriculture (USDA) Forest Service issues an extreme fire danger warning.
x Metrics- To ensure the protocols and steps taken in this Plan are effective, GWP shall develop metrics to evaluate and track the City’s compliance with this Plan. These protocols shall be easily-accessible to City personnel and may include metrics such as the number of unmitigated poles, square feet o f l a n d w i t h i n e a c h “ t i e r ” c o n t a i n i n g unmitigated equipment, average number of months since the previous brush clearing in a particular geographic zone, average rainfall in the previous 12 months, or an aggregate score per asset indicating the relative wildfire risk posed by the asset. These metrics shall tie directly to the stated goals of the Plan and shall be tracked over time to indicate progress toward, or away from, the Plan’s stated goals. During the annual review, the metrics shall be evaluated for effectiveness and may be updated as appropriate to ensure a close match between the activities driven by the Plan and stated goals.
Wildfire Resource Directory
Glendale Fire Department: The Glendale Fire Department is responsible for fire suppression on all private lands within the city of Glendale. The Glendale Fire Department constantly monitors the fire hazard in the city and has ongoing programs for investigation and alleviation of hazardous situations. Firefighting resources in the immediate Glendale Local Hazard Mitigation Plan Section 7: Wildfires
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area are provided by Glendale Fire Department Station Nos. 21, 22, 23, 24, 25, 26, 27, 28, and
29. The Fire Department is comprised of 12 fire companies with nine engine companies and three truck companies. The Department also staffs six Basic Life Support (BLS) ambulances.
These data are summarized by fire station on Table 7-4 below. Staffing at these stations is as follows: 4 crew per each ladder truck and engine company, and two Emergency Medical Technicians (EMTs) per each BLS ambulance.... The Glendale Fire Department is a member of the Verdugo Fire Communications Center (VFCC) that provides dispatch services to nine cities, including Glendale.
Table 7-4: Fire Stations and Facilities in the City of Glendale
Fire
Station
No.
Street
Address
Fire Companies and Ambulances
Engine
Companies
Ladder
Truck
Companies
Rescue
Ambulances
HAZMAT
Unit
Air
Utility
21 421 Oak
Street
1 1 1 0 0
22 1201 S.
Glendale
Ave.
1 0 1 0 0
23 3303 E.
Chevy
Chase
Drive
1 0 0 0
24 1734
Canada
Blvd.
1 0 0 1
25 353 N.
Chevy
Chase
Drive
1 0 1 0
26 1145 N.
Brand
Blvd.
1 1 1 0
27 1127
Western
Ave.
1 0 1 0
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28 4410 New
York Ave.
1 0 0 0 1
29 2465
Honolulu
Ave.
1 1 1 0
Facility Street Address
Verdugo Fire
Comm. Dispatch
421 Oak Street
Environmental
Mgmt. Ctr./FPB
780 Flower Street
Glendale has automatic aid agreements with the adjacent cities of Burbank, Pasadena, Los Angeles, and with the County of Los Angeles. These agreements obligate the departments to help each other under pre-defined circumstances. Automatic aid agreements obligate the nearest fire company to respond to a fire regardless of the jurisdiction. Mutual aid agreements obligate fire department resources to respond outside of their district upon request for assistance.
The Glendale Fire Department is party to an agreement that authorizes calls for emergency response to be dispatched through the Verdugo Fire Communications Center, which coordinates 33 different stations in the region. This “region” includes stations not only from Glendale, but also from Burbank, Pasadena, San Marino, South Pasadena, Monrovia, Arcadia, Sierra Madre and San Gabriel. The Verdugo Fire Communications Center is located on the third floor of Fire Station 21 in Glendale, at 421 Oak Street. Dialing 911 in any of the cities served by the Verdugo Fire Communications Center connects the caller to police or California Highway Patrol dispatchers, who determine the nature of the emergency, and transfer fire and paramedic calls to the Verdugo Fire Communications Center. A dispatcher at the center enters the pertinent details into the computer for transmittal via radio to the fire station that is dispatched for that particular incident. Emergency personnel are on the road within 1 to 2 minutes of receiving the call and remain in constant radio contact with the Verdugo Fire Communications Center as additional details are received.
Numerous other agencies are available to assist the City if needed. Several Federal agencies have roles in fire hazard mitigation, response, and recovery, including: The Fish and Wildlife Local Hazard Mitigation Plan Section 7: Wildfires
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Service, National Park Service, US Forest Service, Natural Resource Conservation Service, Office of Aviation Services, National Weather Service, and National Association of State Foresters. The State Office of Emergency Services can be called upon for further aid if necessary, as can Federal agencies, including the Department of Agriculture, the Department of the Interior, and, in extreme cases, the Department of Defense. Private companies and individuals may also assist.
County Resources:
Los Angeles County Fire Department
1320 N. Eastern Ave.
Los Angeles, CA. 90063
Telephone: (323).881-2411
http://www.lacofd.org/default.htm
State Resources:
California Division of Forestry & Fire Protection
1416 9th Street
PO Box 944246
Sacramento California 94244-2460
(916) 653-5123
http://www.fire.ca.gov/php/index.php
Office of the State Fire Marshal (OSFM)
1131 "S" Street
Sacramento, CA 95814
PO Box 944246
Sacramento, CA 94244-2460
Tel. (916) 445-8200
Fax. (916) 445-8509
Federal Resources and Programs:
The role of the federal land managing agencies in the wildland /urban interface is reducing fuel hazards on the lands they administer; cooperating in prevention and education programs; providing technical and financial assistance; and developing agreements, partnerships and relationships with property owners, local protection agencies, states and other stakeholders in wildland/urban interface areas. These relationships focus on activities before a fire occurs, which render structures and communities safer and better able to survive a fire occurrence.
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Federal Emergency Management Agency (FEMA) Programs: FEMA is directly responsible for providing fire suppression assistance grants and, in certain cases, major disaster assistance and hazard mitigation grants in response to fires. The role of FEMA in the wildland /urban interface is to encourage comprehensive disaster preparedness plans and programs, increase the capability of state and local governments and provide for a greater understanding of FEMA programs at the Federal, State and local levels. x Fire Suppression Assistance Grants: Fire Suppression Assistance Grants may be provided to a state with an approved hazard mitigation plan for the suppression of a forest or grassland fire that threatens to become a major disaster on public or private lands. These grants are provided to protect life and improved property and encourage the development and implementation of viable multi-hazard mitigation measures and provide training to clarify FEMA's programs. The grant may include funds for equipment, supplies and personnel. A Fire Suppression Assistance Grant is the form of assistance most often provided by FEMA to a state for a fire. o The grants are cost-shared with states. FEMA’s US Fire Administration (USFA) provides public education materials addressing wildland/urban interface issues and the USFA's National Fire Academy provides training programs. x FEMA Hazard Mitigation Grant Program: Following a major disaster declaration, the FEMA Hazard Mitigation Grant Program provides funding for long-term hazard mitigation projects and activities to reduce the possibility of damages from all future fire hazards and to reduce the costs to the nation for responding to and recovering from the disaster.
National Wildland/Urban Interface Fire Protection Program:
Federal agencies can use the National Wildland/Urban Interface Fire Protection Program to focus on wildland/urban interface fire protection issues and actions. The Western Governors' Association (WGA) can act as a catalyst to involve state agencies, as well as local and private stakeholders, with the objective of developing an implementation plan to achieve a uniform, integrated national approach to hazard and risk assessment and fire prevention and protection in the wildland/urban interface. The program helps states develop viable and comprehensive wildland fire mitigation plans and performance-based partnerships.
U.S. Forest Service:
The U. S. Forest Service (USFS) is involved in a fuel-loading program implemented to assess fuels and reduce hazardous buildup on forest lands. The USFS is a cooperating agency and, Local Hazard Mitigation Plan Section 7: Wildfires
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while it has little to no jurisdiction in the lower valleys, it has an interest in preventing fires in the interface, as fires often burn up the hills and into the higher elevation US forest lands.
Other Federal and National Resources:
Federal Wildland Fire Policy, Wildland/Urban Interface Protection This is a report describing federal policy and interface fire. Areas of needed improvement are identified and addressed through recommended goals and actions. http://www.fs.fed.us/land/wdfire7c.htm
National Fire Protection Association (NFPA)
This is the principal federal agency involved in the National Wildland/Urban Interface Fire Protection Initiative. NFPA has information on the Initiatives programs and documents.
Public Fire Protection Division
1 Battery March Park.
P.O. Box 9101
Quincy, MA 02269-9101
Phone: (617) 770-3000
National Interagency Fire Center (NIFC)
The NIFC in Boise, Idaho is the nation’s support center for wildland firefighting. Seven federal agencies work together to coordinate and support wildland fire and disaster operations. These agencies include the Bureau of Indian Affairs, Bureau of Land Management, Forest Service, Fish and Wildlife Service, National Park Service, National Weather Service and Office of Aircraft
National Interagency Fire Center
3833 S. Development Ave.
Boise, Idaho 83705
(208) 387-5512
http://www.nifc.gov/
United States Fire Administration (USFA) of the Federal Emergency Management Agency (FEMA)
As an entity of the Federal Emergency Management Agency, the mission of the USFA is to reduce life and economic losses due to fire and related emergencies through leadership, advocacy, coordination and support.
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USFA, Planning Branch, Mitigation Directorate
16825 S. Seton Ave.
Emmitsburg, MD 21727
(301) 447-1000
http://www.fema.gov/hazards/fires/wildfires.shtm - Wildfire Mitigation http://www.usfa.fema.gov/index.htm - U.S. Fire Administration Additional Resources:
Firewise - The National Wildland/Urban Interface Fire program Firewise maintains a Website designed for people who live in wildfire prone areas, but it also can be of use to local planners and decision makers. The site offers online wildfire protection information and checklists, as well as listings of other publications, videos and conferences.
Firewise
1 Battery March Park.
P.O. Box 9101
Quincy, MA 02269-9101
Phone: (617) 770-3000
http://www.firewise.org/
Publications:
National Fire Protection Association Standard 299: Protection of Life and Property from Wildfire, National Wildland/Urban Interface Fire Protection Program, (1991), National Fire Protection Association, Washington, D.C.
Fire Statistics (2017) Cal Fire
http://cdfdata.fire.ca.gov/incidents/incidents_stats?year=2017 National Fire Protection Association Publications (2017) http://www.nfpa.org or http://www.firewise.org
This document, developed by the NFPA Forest and Rural Fire Protection Committee, provides criteria for fire agencies, land use planners, architects, developers and local governments to use in the development of areas that may be threatened by wildfire.
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Hirsch, K., Pinedo, M., & Greenlee, J. An International Collection of Wildland- Urban Interface Resource Materials (Information Report NOR- 344), (1996). Edmonton, Alberta: Canadian Forest Service.
This is a comprehensive bibliography of interface wildfire materials. Over 2,000 resources are included, grouped under the categories of general and technical reports, newspaper articles and public education materials. The citation format allows the reader to obtain most items through a library or directly from the publisher. The bibliography is available in hard copy or diskette at no cost. It is also available in downloadable PDF form.
Canadian Forest Service, Northern Forestry Centre, I-Zone Series Phone: (780) 435-7210
http://www.prefire.ucfpl.ucop.edu/uwibib.htm
Wildland/Urban Interface Fire Hazard Assessment Methodology.
National Wildland/Urban Interface Fire Protection Program, (1998).
NFPA, Washington, D.C.
Firewise (NFPA Public Fire Protection Division)
http://www.firewise.org
Fire Protection in the Wildland/Urban Interface: Everyone’s Responsibility.
National Wildland/Urban Interface Fire Protection Program, (1998). Washington, D.C.
Firewise (NFPA Public Fire Protection Division)
http://www.firewise.org
Caitlyn Pollihan, Executive Director, Council of Western State Foresters, and NASF Fire Suppression Lead, The Flame Act, (2009)
Heinsch, F. A.; Andrews, P. L. BehavePlus fire modeling system, version 5.0: Design and Features. General Technical Report RMRS-GTR-249. (2010) U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station
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SECTION 8: FLOODS
Table of Contents
Why are Floods a Threat to the Cit y o f G l e n d a l e ? 8 - 2 History of Flooding in the City o f G l e n d a l e 8 - 5 Historic Flooding in Los Angeles County 8-8
W h a t F a c t o r s C r e a t e F l o o d R i s k ? 8 - 1 1 How Are Flood-Prone Areas Identified 8-17
F l o o d T e r m i n o l o g y 8 - 1 7
D a m F a i l u r e F l o o d i n g 8 - 2 1
The Effect of Development on Floods: 8-24
H a z a r d A s s e s s m e n t 8 - 2 6
C o m m u n i t y F l o o d I s s u e s 8 - 3 1 C o m m u n i t y I s s u e s S u m m a r y 8 - 3 9 F l o o d M i t i g a t i o n A c t i o n I t e m s 8 - 3 9 F l o o d R e s o u r c e D i r e c t o r y 8 - 4 3 P u b l i c a t i o n s 8 - 4 8
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Why are Floods a Threat to the City of Glendale?
Many California residents face special risks from wildfires, which dramatically alter the landscape and ground conditions in the state. The charred ground that these fires produce lacks vegetation that typically helps to absorb and slow excess water, increasing the likelihood of flooding and mudflows. As rainwater moves across charred and denuded ground, it picks up soil and sediment and carries it in a stream of floodwaters – causing significant damage to nearby properties. Wildfires damaged more than 100,000 acres in 2010 and more than 1.3 million acres in 2008. In 2009 the “Station” fire damaged more than 160,000 acres in Los Angeles County alone.
The City of Glendale and surrounding areas are, like most of Southern California, subject to unpredictable seasonal rainfall. Most years, the scant winter rains are only enough to turn the hills green for a few weeks, but every few years the region is subjected to periods of intense and sustained precipitation that result in flooding. Flood events that occurred in 1969, 1978, 1980, 1983, 1992, 1995, and 1998 have caused an increased awareness of the potential for public and private losses as a resul t o f t h i s h a z a r d , p articularly in highly urbanized parts of floodplains and alluvial fans. As the population in Los Angeles County increases, there is an increased pressure to build on flood-prone areas, and in areas upstream of already developed areas. With increased development, there is also an increase in impervious surfaces, such as asphalt. Water that used to be absorbed into the ground becomes runoff to downstream areas. If the storm drain systems are not designed or improved to convey these increased flows, areas that may have not flooded in the past may be subject to flooding in the future. This is especially true for developments at the base of the mountains and downstream from canyons that have the potential to convey mudflows.
Glendale is drained by the south-, southwest-, and west-flowing Verdugo Wash and its tributaries (see Map 8-1). The Verdugo Wash ultimately drains onto the larger Los Angeles River at the city’s western boundary. Several streams are tributary to the Verdugo Wash.
From north to south in Glendale, these include Cooks Canyon, Dunsmore Canyon, and Ward Canyon. Streams or channels that flow out of the San Gabriel Mountains, through the La Crescenta and La Cañada – Flintridge areas and into Verdugo Wash include Shields Canyon, Local Hazard Mitigation Plan Section 8: Floods
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Eagle Canyon, Pickens Canyon, Hall Beckley Canyon, and Winery Canyon. Several streams emanate from the north and east sides of the Verdugo Mountains and make their way into Verdugo Wash as well. These include, again from north to south, La Tuna, Las Barras, Sheep Corral, Cunningham, Henderson, Engleheard, Deer and Dead Horse Canyons.
In the western portion of the city, the Burbank Western Channel extends through a small portion of Glendale on the channel’s final stretch before emptying into the Los Angeles River.
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Map 8-1: Geomorphic Map of Glendale Showing the Canyons Referred to in the Text
Other canyons draining off the south flank of the Verdugo Mountains include, from west to Local Hazard Mitigation Plan Section 8: Floods
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east, Childs, Brand, Idlewood, Sherer, Hillcrest, Toll, Brookman and Mand Canyons. Several small and two large canyons drain the western and southwestern portions of the San Rafael Hills. Most of the small canyons in the northwestern portion of the San Rafael Hills are unnamed, except for Kirby Canyon. The two large ones are Sycamore Canyon and Scholl Canyon. There are also a few unnamed streams in the San Rafael Hills whose headwaters are in Glendale but drain to the east, toward Arroyo Seco. Several of the canyons in the San Gabriel and Verdugo Mountains have debris basins that were built for flood protection purposes. Most of the streams off the San Gabriel Mountains have been channelized through the La Cañada Valley for flood-protection purposes. Similarly, Verdugo Wash is channelized through Glendale.
History of Flooding in the City of Glendale:
Floods of consequence to the City of Glendale are typically of the flash flood type, of short duration, but with high peak volumes and high velocities. This type of flooding occurs in response to the local geology, geography, and the built environment. The mountains in the north of the City consist of rock that is predominantly impervious to water that rainwater instead flows along the surface as runoff. When a major storm moves in, water collects rapidly and runs off quickly, making a steep, rapid descent from the mountains onto the alluvial fans and ultimately into Verdugo Wash.
The most severe flood recorded in Glendale occurred in 1934. Intense precipitation on New Year’s Eve, 1933 occurred locally in the La Canada-Flintridge area, causing the Verdugo Wash to swell and overflow its then natural channel. Extensive areas of the drainage basin had burned earlier in November 1933, causing large amounts of debris. The debris was carried by the storm waters down the mountains, and into the alluvial valleys. More than 40 people died, several bridges were washed out, and 400 properties were damaged. Other significant floods have occurred during the years until the most recent rain storms of January 2010. This storm is a concern to the City due to the Station Fire of August and September 2009 burned 160,000 acres in Los Angeles County. Approximately 690 acres of the 709 acres Deukmejian Wilderness Park in northern Glendale were burned on September 1, 2009.
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Several canyons near the Glendale area have also flooded in the past, impacting developments within the canyons or areas downstream. For example, during the storms of 1969, the Verdugo Hills and the city proper were impacted by debris flows and flood flows when tributary streams reportedly overtopped their debris basins, causing damage (Waananen, 1969).
Stream gage records show that maximum daily peak flows in the lower reaches of Verdugo Wash are typically less than about 400 cubic feet per second (cfs), with many years actually measuring peaks of considerably less than 100 cfs. However, maximum daily peak flows have occasionally exceeded 1,000 cfs (in 1937-38, 1942-43, 1965-66, 1968-69, 1977-78, 1982-83, 1994-95, 1995-96, and 1996-97).
In the decades between 1930 and 1990, maximum daily peak flows exceeding 1,000 cfs generally occurred only once in a decade, but in the1990s there were three consecutive years when this channel had maximum daily peak flows exceeding 1,000 cfs (and in the 1997-98 water year, the maximum daily peak flow was 966 cfs, also high for the area). The records show that annual discharges in the last decades are overall higher than the measurements for the previous four decades. This may indicate that climate has been wetter in the last few decades (possibly as a result o f g l o b a l w a r m i n g ) , o r i t c o u l d m e a n t h a t w i t h i n c r e a s e d development in the Verdugo drainage area, the Verdugo Wash receives more runoff.
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Map 8-2: Effects of the 1934 Flood in Glendale
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The highest peak flow recorded in Verdugo Wash is for the water year of 1968-69, with a maximum daily peak flow of 1,850 cfs. However, there are two years for which there are no records, in 1933-34, and 1983-84. The lack of data for 1933-34 is probably the result of the gage being washed out during the worst flood recorded for Verdugo Wash, as discussed above. Similarly, the winter storms in 1983-84 caused considerable damage in southern California and may have also washed out the gage.
The City of Glendale most recently experienced some destruction during the 2005 floods.
Residents and business owners who were impacted by flooding and the rain storms were able to receive disaster assistance through the Federal Emergency Management Agency and the City. On February 4, 2005, President Bush declared that a major disaster existed in California and ordered Federal aid to supplement State and local recovery efforts.
Historic Flooding in Los Angeles County:
There are several rivers in the southern California region, but the river with the best- recorded history is the Los Angeles River. The flood history of the Los Angeles River is generally indicative of the flood history of much of southern California. Records show that since 1811, the Los Angeles River has flooded 30 times, roughly about once every 6 years.
But averages are deceiving, for the Los Angeles basin goes through periods of drought and then periods of above-average rainfall. For example, between 1868 and 1884, a period of 16 years, there were no major floods, but this was followed by a series of wet years with floods in 1885, 1886, 1889 and 1891. A similar cluster of wet years was recorded in the 1990s, as discussed above.
Table 8-1: Historical Floods in Los Angeles County
Year Comments
1770-
1771
Great flooding on the L.A. River recorded by Father Juan Crespi. River overflowed its channel.
1771-
1772
Flooding recorded by Spanish Mission Fathers. San Gabriel Mission crops destroyed.
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Year Comments
1775-
1776
Due to heavy flooding, San Gabriel Mission was moved about 6 miles back from the river.
1779-
1780
Flooding recorded by Spanish Mission Fathers. Flows filled riverbed and flooded the lowlands where wheat and barley had been planted. 1811 Flooding reported, although records are sparse.
1815 Flooding washes away the original Plaza in L.A. River changes course at Alameda and 4th Street to cut west and join Ballona Creek. From there it emptied into Santa Monica Bay.
1822 A great flood on the L.A. River “covered all the lowlands and reached a greater height than was ever known before.”
1824-
25 The greatest of the earlier recorded floods. L.A. River changed its course back from the Ballona wetlands to San Pedro. Before this storm, the river would spread over the entire area, filling depressions at the surface and forming lakes, ponds and marshes, rarely discharging its waters into the sea. The 1825 floods cut a riverway to the ocean, draining the marshlands and causing the forests to disappear.
1832 Heavy flooding caused the drainage near Compton to change so that many lakes and ponds that “had been permanent, became dry a few years thereafter.” Drainage of these ponds and lakes completed the destruction of the forests that used to cover a large part of southern L.A. County.
1849 –
1860
Floods of various magnitudes occurred in 1849-1850, 1851-1852, and 1859- 1860.
1861-
62 The “great flood” or the “Noachian deluge of California.” Fifty inches of rain fell during December and January. The entire valley from Los Angeles to the ocean was a great lake. Part of the river split and drained into Ballona Creek. San Gabriel River also overflowed its banks and started a new channel. 1867-
68 Floods spill over river channel and create a large, temporary lake out to Ballona Creek. San Gabriel River breaks out of its channel and washes thousands of acres of land.
1884 Two periods of intense rainstorms separated by 6 to 8 days. The first storms caused little damage. The second washed all but one of the bridges across the L.A. River, washed away many houses, and drowned several people. Parts of Los Angeles flooded 3 to 4 feet deep.
1886-
87 A good part of Los Angeles was inundated. The levees were damaged and railway communication was impossible for 2 to 3 weeks.
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Year Comments
1889 Flood on Christmas Day caused much damage; bridges and levees washed away; the old San Gabriel, new San Gabriel and L.A. Rivers joined near Downey and formed one body. L.A. River overtopped its channel.
1914 Heavy flooding in January and February. Great damage to L.A. harbor. 1916-
1938
Flooding in 1916. Minor floods causing damage in certain areas reported in 1918, 1921-1922, 1926, 1927, 1931, 1932, 1934, 1936, and 1937. 1934 Moderate to severe flooding starting January 1. Over 40 dead in La Cañada – Glendale area. Debris flow killed 12 people who had taken shelter in the Montrose Legion Hall.
1938 Series of storms beginning December 1937. March floods exceeded all previous floods for which records were available. Large tracts inundated; bridges, highways and railroads severely damaged. 87 people killed, over $78 Million (1938 dollars) in damage.
1941-
1944
Los Angeles River floods five times.
1952 Moderate flooding.
1969 Recurrent precipitation during January and February nearly approached the largest total since 1884. Nearly 40 people died as direct result of the floods in southern California, and more than 10,000 had to be evacuated. 1978 Two moderate floods.
1979 Los Angeles experiences severe flooding and mudslides. 1980 Flood tops banks of river in Long Beach. Sepulveda Basin spillway almost opened.
1983 Flooding kills six people.
1992 15-year flood. Motorists trapped in Sepulveda basin. Six people dead. 1994-
1995
Heavy flooding throughout the State. The total damages are estimated at $2 billion.
1997-
98 The 1997 floods caused extensive damage in 48 California counties, including Los Angeles County. Total damages were estimated at $1.8 billion. The 1998 El Niño storms also caused damage, but this was less than it could have been because many had taken measures to reduce their risk following the 1997 storms.
2003-
2004
The rains followed the extensive fires of 2003; in many areas, canyons chocked with ashes and debris caused debris flows that did substantial damage downstream.
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Year Comments
2004-
05 The second-wettest year on record in the Los Angeles Basin; the rains caused extensive damage in some areas, triggering landslides and debris flows. 2009-
10-11
Rainfall on steep burned basins can quickly transform into potentially dangerous flash floods and debris flows as a result from the Station Fire (2009)
What Factors Create Flood Risk?
Climate:
Flooding occurs when climate, geology, and hydrology combine to create conditions where water flows outside of its usual course. In the City of Glendale, geography and climate may combine to create seasonal flooding conditions. The Santa Monica, Santa Susana, and Verdugo Mountains, which surround three sides of the San Fernando valley, seldom reach heights above three thousand feet. The western San Gabriel Mountains, in contrast, have elevations of more than seven thousand feet. These higher ridges often trap east-moving winter storms. Although downtown Los Angeles averages just fifteen inches of rain a year, some mountain peaks in the San Gabriel Mountains receive more than forty inches of precipitation annually.
Naturally, this rainfall moves rapidly downstream, often with severe consequences for anything in its path. Storm events are likely to generate debris flows in the upper reaches of the watershed. In extreme cases, flood-generated debris flows will roar down a canyon at speeds near 40 miles per hour with a wall of mud, debris and water tens of feet high. Debris flows, such as those that impacted Glendale in 1934, often occur in areas recently burned by wildfires, where vegetation has not yet formed a protective ground cover that helps keep the soil in place. Furthermore, the oils in the plants native to southern California, when burned, react with the soils, making them water repellant. As a result, less rainwater than usual infiltrates the ground, and instead makes its way downslope as runoff, carrying ashes and other burned debris with it.
Average yearly precipitation in the downtown Glendale area is about 17 to 18 inches, Local Hazard Mitigation Plan Section 8: Floods
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whereas the northern reaches of the city, near La Crescenta, receive 23 to 24 inches per year, on average. In general, areas closer to the San Gabriel Mountains receive higher precipitation rates than areas farther south from the mountains. This is because, as explained above, the mountains often capture precipitation from strong, east-moving Pacific storms. The mountains therefore separate the semi-arid environment to the west, within the Los Angeles basin, from the dry desert environment to the east, in the Mojave Desert. “Averages” are not particularly representative of rainfall in the Southern California area, as illustrated with the following discussion about downtown Los Angeles: the average annual rainfall in Los Angeles for the last 125 years is 14.9 inches, but rainfall during this time period has ranged from only 4.35 inches in 2001-2002 to 38.2 inches in 1883-1884. In fact, in only fifteen of the past 125 years has the annual rainfall been within plus or minus 10 percent of the 14.9-inch average, and in only 38 years has the annual rainfall been within plus or minus 20 percent of the average value. This makes the Los Angeles basin a land of extremes in terms of annual precipitation.
There are three types of storms that produce precipitation in Southern California: winter storms, local thunderstorms, and summer tropical storms (or monsoons). These are described below.
x Winter Rainfall: Winter storms are characterized by heavy and sometimes prolonged precipitation over a large area. These storms usually occur between November and April and are responsible for most of the precipitation recorded in Southern California. The storms originate over the Pacific Ocean and move eastward (and inland). The mountains, such as the San Gabriel and San Bernardino Mountains, form a rain shadow, slowing down or stopping the eastward movement of this moisture. A significant portion of the moisture is dropped on the mountains as snow.
If large storms are coupled with snowmelt from these mountains, large peak discharges can be expected in the main watersheds at the base of the mountains.
Some of the severe winter storm seasons that have historically impacted the Southern California area have been related to El Niño events.
El Niño is the name given to a phenomenon that starts every few years, typically in December or early January, in the southern Pacific off the western coast of South America, but whose impacts are felt worldwide. Briefly, warmer than usual waters in the southern Pacific are statistically linked with increased rainfall in both the southeastern and southwestern United States, droughts in Australia, western Africa Local Hazard Mitigation Plan Section 8: Floods
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and Indonesia, reduced number of hurricanes in the Atlantic Ocean, and increased number of hurricanes in the Eastern Pacific. Two of the largest and most intense El Niño events on record occurred during the 1982-83 and 1997-98 water years. [A water year is the 12-month period from October 1 through September 30 of the second year. Often a water year is identified only by the calendar year in which it ends, rather than by giving the two years, as above.] These are also two of the worst storm seasons reported in Southern California.
x Thunderstorms and Monsoons: Another relatively regular source of heavy rainfall, particularly in the mountains and adjoining cities, is from summer tropical storms.
Tropical rains or monsoons are infrequent, and typically occur in the summer or early fall. These storms originate in the warm, southern waters off Baja California, in the Pacific Ocean, and move northward into southern California. Tropical storms that have dropped significant rainfall in the southern California area in the last 100 years or so are listed in Table 8-2 below. Thunderstorms can occur at any time but are usually more prevalent in the higher mountains during the summer. Thunderstorms usually impact relatively small areas.
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Table 8-2: Tropical Storms That Affected Southern California during the 20th Century
Month-
Year
Date(s) Area(s) Affected Rainfall
July 1902 20th &
21st
Deserts and southern mountains up to 2"
Aug. 1906 18th &
19th
Deserts and southern mountains up to 5"
Sept. 1910 15th Mountains of Santa Barbara County 2"
Aug. 1921 20th &
21st
Deserts and southern mountains up to 2"
Sept. 1921 30th Deserts up to 4"
Sept. 1929 18th Southern mountains and deserts up to 4" Sept. 1932 28th - Oct
1st
Mountains and deserts, 15 fatalities up to 7
Aug. 1935 25th Southern valleys, mountains and deserts up to 2" Sept. 1939 4th - 7th Southern mountains, southern and eastern deserts up to 7 11th &
12th
Deserts, central and southern mountains up to 4"
19th - 21st Deserts, central and southern mountains up to 3" 25th Long Beach, with sustained winds of 50 MPH 5"
Surrounding mountains 6 to 12"
Sept. 1945 9th & 10th Central and southern mountains up to 2” Sept. 1946 30th - Oct
1st
Southern mountains up to 4"
Aug. 1951 27th - 29th Southern mountains and deserts 2 to 5" Sept. 1952 19th - 21st Central and southern mountains up to 2" July 1954 17th - 19th Deserts and southern mountains up to 2" July 1958 28th &
29th
Deserts and southern mountains up to 2"
Sept. 1960 9th & 10th Julian 3.40"
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Sept. 1967 1st - 3rd Southern mountains and deserts 2"
Oct. 1972 6th Southeast deserts up to 2"
Sept. 1976 10th &
11th
Central and southern mountains. Ocotillo was
destroyed, 3 fatalities
6 to 12"
Aug. 1977 n/a Los Angeles 2"
Mountains up to 8"
Oct. 1977 6th & 7th Southern mountains and deserts up to 2 Sept. 1978 5th & 6th Mountains 3"
Sept. 1982 24th - 26th Mountains up to 4"
Sept. 1983 20th &
21st
Southern mountains and deserts up to 3"
http://www.fema.gov/nwz97/eln_scal.shtm
Geography and Geology:
The local mountains are very steep and consist of rock types that are fairly impervious to water. Consequently, little precipitation infiltrates the ground; rainwater instead flows across the surface as runoff, collecting in the major drainages that pass through the city.
When a major storm moves in, water collects rapidly and runs off quickly, making a steep, rapid descent from the mountains into man-made and natural channels within developed areas. Because of the steep terrain, scarcity of vegetation, and the constant shedding of debris from mountain slopes (primarily as dry ravel and rock falls), flood flows often carry large amounts of mud, sand, and rock fragments. Sheet flow occurs when the capacities of the existing channels (either natural or man-made) are exceeded and water flows over and into the adjacent areas.
The greater Los Angeles Basin has been shaped by erosion and sedimentation for millennia.
Most of the mountains that ring the valleys and coastal plain have and are being uplifted along movement on faults; this movement has fractured the bedrock, allowing for their brittle slopes to be readily eroded. Rivers and streams have then carried boulders, rocks, gravel, sand, and silt down these slopes to the valleys and coastal plain. Over time, these sediments have collected in the valley bottoms, so that locally these sediments are as much Local Hazard Mitigation Plan Section 8: Floods
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as twenty thousand feet thick. This sediment generally acts as a sponge, absorbing vast quantities of water received as precipitation in those years when heavy rains follow a dry period. But like a sponge that is near saturation, the same soil fills up rapidly when a heavy rain follows a period of relatively wet weather. So, in some years of heavy rain, flooding is minimal because the ground is relatively dry. The same amount of rain following a wet period, when the ground is already saturated, can cause extensive flooding.
Built Environment:
The greater Los Angeles basin is essentially built out. This leaves precious little open land to a b s o r b r a i n f a l l . T h i s l a c k o f o p e n g r o u n d f o r c e s w a t e r t o r e m a i n o n t h e s u r f a c e a n d accumulate rapidly. If it were not for the massive flood control system that has been built over the years, with its concrete lined rivers and stream beds, flooding in the Los Angeles basin would be a much more common occurrence. And the tendency is towards even less and less open land. In-fill building is becoming a much more common practice in many areas:
Developers tear down older homes, which typically cover up to 40% of the lots that they sit on and replace each of them with three or four town homes or apartments, which may cover 90-95% of the lot. This increase in impervious surfaces (including concrete walkways, and roofs) results in a direct increase in runoff.
Another potential reason for recurrent storm flooding in developed areas is “asphalt creep.” The street space between the curbs of a street is a part of the flood control system. Water leaves the adjacent properties and accumulates in the streets, where it is directed towards the underground portion of the flood control system. The carrying capacity of a given street is determined by the width of the street and the height of the curbs along the street. Often, when streets are being resurfaced, a one- to two-inch layer of asphalt is laid down over the existing asphalt. This added layer of asphalt subtracts from the rated capacity of the street to carry water. Thus, the original engineered capacity of the entire storm drain system is marginally reduced over time. Subsequent re-paving of the street will further reduce its engineered capacity.
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How Are Flood-Prone Areas Identified:
The Federal Emergency Management Agency (FEMA) is mandated by the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973 to evaluate flood hazards. To promote sound land use and floodplain development, FEMA provides Flood Insurance Rate Maps (FIRMs) for local and regional planners. Flood risk information presented on FIRMs is based on historic, meteorological, hydrologic, and hydraulic data, as well as topographic surveys, open-space conditions, flood control works, and existing development.
Rainfall-runoff and hydraulic models are utilized by the FIRM program to analyze flood potential, adequacy of flood protective measures, surface-water and groundwater interchange characteristics, and the variable efficiency of mobile (sand bed) flood channels.
It is important to realize that FIRMs only identify potential flood areas based on the conditions at the time of the study, and do not consider the impacts of future development.
To prepare FIRMs that illustrate the extent of flood hazards in a flood-prone community, FEMA conducts engineering studies referred to as Flood Insurance Studies (FISs). Using information gathered in these studies, FEMA engineers and cartographers delineate Special Flood Hazard Areas (SFHAs) on FIRMs. SFHAs are those areas subject to inundation by a “base flood” which FEMA sets as a 100-year flood (see definitions below).
The NFIP also reduces flood losses through regulations that focus on building codes and sound floodplain management. In the city of Glendale, the NFIP and related building code regulations went into effect on August 31, 1984 (City ID No. – 065030). NFIP regulations (44 Code of Federal Regulations (CFR) Chapter 1, Section 60, 3) require that all new construction in floodplains must be elevated at or above base flood level.
Flood Terminology
Floodplain:
A floodplain is a land area adjacent to a river, stream, lake, estuary, or other water body that is subject to flooding. This area, if left undisturbed, acts to store excess floodwater. The floodplain is made up of two sections: the floodway and the flood fringe.
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100-Year Flood:
The 100-year flooding event is the flood having a one percent chance of being equaled or exceeded in magnitude in any given year. Contrary to popular belief, it is not a flood occurring once every 100 years. The 100-year floodplain is the area adjoining a river, stream, or watercourse covered by water in the event of a 100-year flood. A 100-year flood is defined by looking at the long-term average period between floods of a certain size and identifying the size of flood that has a 1 percent chance of occurring during any given year.
This base flood has a 26 percent chance of occurring during a 30-year period, the length of most home mortgages. However, a recurrence interval such as “100 years” represents only the long-term average period between floods of a specific magnitude; rare floods can in fact occur at much shorter intervals or even within the same year.
Floodway:
The floodway is one of two main sections that make up the floodplain. Floodways are defined for regulatory purposes. Unlike floodplains, floodways do not reflect a recognizable geologic feature. For National Flood Insurance Program (NFIP) purposes, floodways are defined as the channel of a river or stream, and the overbank areas adjacent to the channel. The floodway carries the bulk of the floodwaters downstream and is usually the area where water velocities and forces are the greatest. NFIP regulations require that the floodway be kept open and free from development or other structures that would obstruct or divert flood flows onto other properties.
Glendale regulations prohibit all development in the floodway. The NFIP floodway definition is "the channel of a river or other watercourse and adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot.” Floodways are not mapped for all rivers and streams but are generally mapped in developed areas.
Flood Fringe:
The flood fringe refers to the outer portions of the floodplain, beginning at the edge of the floodway and continuing outward. Generally, the flood fringe is defined as "the land area Local Hazard Mitigation Plan Section 8: Floods
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which is outside of the stream flood way but is subject to periodic inundation by regular flooding.” This is the area where development is most likely to occur, and where precautions to protect life and property need to be taken.
Development:
For floodplain ordinance purposes, development is broadly defined as "any man-made change to improved or unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation, or drilling operations located within the area of special flood hazard." The definition of development for floodplain purposes is generally broader and includes more activities than the definition of development used in other sections of local land use ordinances.
Base Flood Elevation (BFE):
The term "Base Flood Elevation" refers to the elevation (normally measured in feet above sea level) that the base flood is expected to reach. Base flood elevations can be set at levels other than the 100-year flood. Some communities choose to use higher frequency flood events as their base flood elevation for certain activities, while using lower frequency events for others. For example, for the purpose of storm water management, a 25-year flood event might serve as the base flood elevation, whereas the 500-year flood event may serve as base flood elevation for the tie down of mobile homes. The regulations of the NFIP focus on development in the 100-year floodplain.
Storm Flooding Characteristics
Three primary types of flooding have historically affected the southern California area, including the city of Glendale: riverine flooding, urban flooding, and debris flows (see descriptions below). (Areas near the coastline are also susceptible to coastal flooding but given that the city of Glendale is located inland, this type of flooding will not be discussed). x Riverine Flooding: Riverine flooding is the overbank flooding of rivers and streams.
This process in a natural environment adds sediment and nutrients to the flooded area, cyclically enhancing the fertility of the soils, which is why floodplains have been the breadbaskets of civilizations through the ages. However, large floods have the Local Hazard Mitigation Plan Section 8: Floods
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potential to cause significant damage to man-made structures and causing significant loss of life. Flooding in large river systems typically results from large-scale weather systems that generate prolonged rainfall over a wide geographic area, causing flooding in hundreds of smaller streams, which then drain into the major rivers.
Shallow area flooding is a special type of riverine flooding. FEMA defines shallow flood hazards as areas that are inundated by the 100-year flood with flood depths of only one to three feet. These areas are generally flooded by low velocity sheet flows of water.
x Urban Flooding: As land is converted from agricultural fields or woodlands to roads and parking lots, it loses its ability to absorb rainfall. Urbanization of a watershed changes the hydrologic systems of the basin. Heavy rainfall collects and flows faster on impervious concrete and asphalt surfaces. The water moves from the clouds, to the ground, and into streams at a much faster rate in urban areas. Adding these elements to the hydrological systems can result in floodwaters that rise very rapidly and peak with violent force. The flooding of developed areas often occurs when the amount of water generated from rainfall and runoff exceeds the storm water system’s capability to remove it.
Over 50 percent of the Glendale area has a high concentration of impervious surfaces that either collect water or concentrate the flow of water in channelized or man- improved channels. During periods of urban flooding, streets can become swift moving rivers and basements can fill with water. Storm drains may also back up with vegetation and debris causing additional, localized flooding. x Debris Flows: Another flood related hazard that can affect certain parts of the southern California region is debris flows. Debris flows most often occur in mountain canyons and at the foothills of the large mountains that serve as backdrop to the area.
However, any hilly or mountainous area with intense rainfall and the proper geologic conditions may experience one of these very sudden and devastating events.
Debris flows, sometimes referred to as mudslides, mudflows, or debris avalanches, are common types of fast-moving landslides that generally occur during periods of intense rainfall or rapid snow melt. They usually start on steep hillsides as shallow landslides that liquefy and accelerate to speeds that are typically about 10 miles per hour but can exceed 35 miles per hour. The consistency of debris flow ranges from watery mud to thick, rocky mud that can carry large items such as boulders, trees, and cars. Debris flows from many different sources can combine in channels, and their destructive power may be greatly increased. They continue flowing down hills and through channels, growing in volume with the addition of water, sand, mud, boulders, trees, and other materials. When the flows reach flatter ground, the debris spreads over a broad area, sometimes accumulating in thick deposits that can wreak havoc in developed areas.
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Dam Failure Flooding
Seismically induced inundation refers to flooding that results when water retention structures (such as dams) fail due to an earthquake. Failure of these structures can also result from other causes, such as overtopping, foundation problems, or construction errors.
Statutes governing dam safety are defined in Division 3 of the California State Water Code (California Department of Water Resources, 1986). These statutes empower the California Division of Dam Safety to monitor the structural safety of dams that are greater than 25 feet in dam height or have more than 50 acre-feet in storage capacity.
Dams under State jurisdiction are required to have inundation maps that show the potential flood limits in the remote, yet disastrous possibility, that a dam is catastrophically breached.
Inundation maps are prepared by dam owners to help with contingency planning; these inundation maps in no way reflect the structural integrity or safety of the dam in question.
Because dam failure can have severe consequences, FEMA requires that all dam owners develop Emergency Action Plans (EAP) for warning, evacuation, and post-flood actions.
Although there may be coordination with county officials in the development of the EAP, the responsibility for developing potential flood inundation maps and facilitation of emergency response is the responsibility of the dam owner. Dam owners are also required to prepare and submit emergency response plans to the State Office of Emergency Services, the lead State agency for the State dam inundation-mapping program. Cities and counties are required by State law to have in place emergency procedures for the evacuation and control of populated areas within the limits of dam inundation. In addition, recent legislation requires real estate disclosure upon sale or transfer of properties in the inundation area (AB 1195 Chapter 65, June 9, 1998; Natural Hazard Disclosure Statement).
There has been a total of 45 dam failures in California since the 19 th century. The most
significant dam failures in southern California are listed in Table 8-3, and the two most significant dam failures, St. Francis Dam in 1928 and the Baldwin Hills Dam in 1963, are described further below.
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Table 8-3: Dam Failures in Southern California
Dam Name Location Year Failure Mechanism
Sheffield Santa Barbara 1925 Earthquake slide
Puddingstone Pomona 1926 Overtopping during construction Lake Hemet Palm Springs 1927 Overtopping
Saint Francis San Francisquito
Canyon
1928 Sudden failure at full capacity through
foundation, 426 deaths.
Cogswell Monrovia 1934 Breaching of concrete cover
Baldwin Hills Los Angeles 1963 Leak through embankment turned into washout, 3 deaths.
St. Francis Dam, built in 1926 in the San Francisquito Canyon near Saugus, was 180 feet high and 600 feet long. Its failure, and the resulting loss of over 400 lives in the path of a roaring wall of water, was a scandal that resulted in the almost complete destruction of the reputation of its builder, William Mulholland. Mulholland was an immigrant from Ireland who rose up through the ranks of the Los Angeles City water department to the position of chief engineer. It was he who proposed, designed, and supervised the construction of the Los Angeles Aqueduct, which brought water from the Owens Valley to the city.
St. Francis dam gave way on March 12, 1928, three minutes before midnight. Its waters swept through the Santa Clara Valley toward the Pacific Ocean, about 54 miles away. Sixty- five miles of valley were devastated before the water finally made its way into the ocean between Oxnard and Ventura. At its peak, the wall of water was said to be 78 feet high; by the time it hit Santa Paula, 42 miles south of the dam, the water was estimated to be 25 feet deep. Almost everything in its path was destroyed: livestock, structures, railways, bridges, and orchards. By the time it was over, parts of Ventura County lay under 70 feet of mud and debris. Over 400 people were killed and damage estimates topped $20 million.
The Baldwin Hills dam, an earthen dam that created a 19-acre reservoir to supply drinking water to West Los Angeles residents, failed on December 14, 1963 at 3:38 in the afternoon.
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This is one of the first disaster events documented in a live helicopter broadcast - the live telecast of the collapse from a KTLA-TV helicopter is considered the precursor to airborne news coverage that is now routine everywhere. As a pencil-thin crack widened to a 75-foot gash, 292 million gallons surged out. “The Baldwin Hills Dam collapsed with the fury of a thousand cloudbursts, sending a 50-foot wall of water down Cloverdale Avenue and slamming into homes and cars... Five people were killed. Sixty-five hillside houses were ripped apart, and 210 homes and apartments were damaged.” The flood swept northward in a V-shaped path roughly bounded by La Brea Avenue and Jefferson and La Cienega boulevards. It took 77 minutes for the impounded reservoir to empty, but it took a generation for the neighborhood below to recover, illustrating the severe, long-term impact of these disasters. Furthermore, failure of this tank foreshadowed the end of urban-area earthen dams as a major element of the Department of Water and Power’s water storage system. It also prompted a tightening of Division of Safety of Dams control over reservoirs throughout the State.
Flooding due to Failure of Above-Ground Water Storage Tanks:
Seismically induced inundation can also occur if strong ground shaking causes structural damage to above-ground water tanks. If a tank is not adequately braced and baffled, sloshing water can lift a water tank off its foundation, splitting the shell, damaging the roof, and bulging the bottom of the tank (elephants foot) (EERI, 1992). Movement can also shear off the pipes leading to the tank, releasing water through the broken pipes. These types of damage occurred during southern California’s 1992 Landers, 1992 Big Bear, and 1994 Northridge earthquakes. The Northridge earthquake alone rendered about 40 steel tanks non-functional (EERI, 1995), including a tank in the Santa Clarita area that failed and inundated several houses below. As a result of lessons learned from recent earthquakes, new standards for design of steel water tanks were adopted in 1994 (Lund, 1994). The new tank design includes flexible joints at the inlet/outlet connections to accommodate movement in any direction. Flexible joints have been installed at most of Glendale’s larger steel tanks.
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available to suppress earthquake-induced fires. Damaged tanks and water mains can also limit the amount of water available to residents. Furthermore, groundwater wells can be damaged during an earthquake, also limiting the water available to the community after an earthquake. Therefore, it is of paramount importance that the water storage tanks in the area retain their structural integrity during an earthquake, so water demands after an earthquake can be met. In addition to evaluating and retrofitting to meet current standards, this also requires that the tanks be kept at near full capacity as much as practical.
The Effect of Development on Floods:
When structures or fill are placed in the floodway or floodplain, water is displaced.
Development raises the river levels by forcing the river to compensate for the flow space obstructed by the inserted structures and/or fill. When structures or materials are added to the floodway or floodplain and no fill is removed to compensate, serious problems can arise.
Flood waters may be forced away from historic floodplain areas. As a result, other existing floodplain areas may experience flood waters that rise above historic levels. Local governments must require engineer certification to ensure that proposed developments will not adversely affect the flood carrying capacity of the Special Flood Hazard Area (SFHA).
Displacement of only a few inches of water can mean the difference between no structural damage occurring in a given flood event, and the inundation of many homes, businesses, and other facilities. Careful attention should be given to development that occurs within the floodway to ensure that structures are prepared to withstand base flood events.
In highly urbanized areas, increased paving can lead to an increase in volume and velocity of runoff after a rainfall event, exacerbating the potential flood hazards. Care should be taken in the development and implementation of storm water management systems to ensure that these runoff waters are dealt with effectively.
How Building Codes Address Building in Known Flood Prone Areas:
Flood Insurance Rate Maps (FIRM) and Flood Insurance Studies (FIS) Floodplain maps are the basis for implementing floodplain regulations and for delineating flood insurance purchase requirements. A Flood Insurance Rate Map (FIRM) is the official map produced by Local Hazard Mitigation Plan Section 8: Floods
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FEMA which delineates SFHA in communities where NFIP regulations apply. FIRMs are also used by insurance agents and mortgage lenders to determine if flood insurance is required and what insurance rates should apply.
Water surface elevations are combined with topographic data to develop FIRMs. FIRMs illustrate areas that would be inundated during a 100-year flood, floodway areas, and elevations marking the 100-year-flood level. In some cases, they also include base flood elevations (BFEs) and areas located within the 500-year floodplain. Flood Insurance Studies and FIRMs produced for the NFIP provide assessments of the probability of flooding at a given location. FEMA conducted many Flood Insurance Studies in the late 1970s and early 1980s. These studies and maps represent flood risk at the point in time when FEMA completed the studies. However, it is important to note that not all 100-year or 500-year floodplains have been mapped by FEMA.
FEMA flood maps are not entirely accurate. These studies and maps represent flood risk at the point in time when FEMA completed the studies and does not incorporate planning for floodplain changes in the future due to new development. Although FEMA is considering changing that policy, it is optional for local communities. There is no FIRM map for the City of Glendale.
Flood Mapping Methods and Techniques:
Although many communities rely exclusively on FIRMs to characterize the risk of flooding in their area, there are some flood-prone areas that are not mapped but remain susceptible to flooding. These areas include locations next to small creeks, local drainage areas, and areas susceptible to man-made flooding.
In order to address this lack of data, jurisdictions can take efforts to develop more localized flood hazard maps. One method that has been employed includes using high-water marks from flood events or aerial photos, in conjunction with the FEMA maps, to better reflect the true flood risk. The use of GIS (Geographic Information System) is becoming an important tool for flood hazard mapping. FIRM maps can be imported directly into GIS, which allows Local Hazard Mitigation Plan Section 8: Floods
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for GIS analysis of flood hazard areas.
Communities find it particularly useful to overlay flood hazard areas on tax assessment parcel maps. This allows a community to evaluate the flood hazard risk for a specific parcel during review of a development request. Coordination between FEMA and local planning jurisdictions is the key to making a strong connection with GIS technology for the purpose of flood hazard mapping.
FEMA and the Environmental Systems Research Institute (ESRI), a private company, have formed a partnership to provide multi-hazard maps and information to the public via the Internet. ESRI produces GIS software, including ArcViewC9 and ArcInfoC9. The ESRI web site has information on GIS technology and downloadable maps. The hazards maps provided on the ESRI site are intended to assist communities in evaluating geographic information about natural hazards. Flood information for most communities is available on the ESRI web site. Visit www.esri.com for more information.
Hazard Assessment
Hazard Identification:
Hazard identification is the first phase of flood-hazard assessment. Identification is the process of estimating: 1) the geographic extent of the floodplain (i.e., the area at risk from flooding); 2) the intensity of the flooding that can be expected in specific areas of the floodplain; and 3) the probability of occurrence of flood events. This process usually results in the creation of a floodplain map. Floodplain maps provide detailed information that can assist jurisdictions in making policies and land-use decisions.
Flood Hazard Mapping for the City of Glendale:
On May 7, 1976, the Federal Insurance Administration (FIA) issued a Flood Hazard Boundary map for the City of Glendale. However, a study of Verdugo Wash conducted in 1978 for the Los Angeles County Department of Public Works (LACDPW) showed that the channel could accommodate the estimated peak flows everywhere, except in the area immediately north of where Verdugo Wash joins the Los Angeles River. In fact, this area is known to flood regularly Local Hazard Mitigation Plan Section 8: Floods
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during winter storms (refer to following sections for further information on this). Based on the information provided by the LACDPW, stating “that for all practical purposes no part of the community would be inundated by the base flood; that is, a flood having a one percent chance of being equaled or exceeded in any given year,” and therefore, that the entire community would be classified as Zone C (area of minimal flood hazards where the purchase of flood insurance is not mandatory), the Flood Hazard Boundary Map was rescinded by FIA on November 15, 1979.
On a letter dated August 31, 1984, FEMA again informed the City that no Special Flood Hazard Areas were present within the corporate limits of the city at that time, and thus that the City was placed in Zone D, which has no mandatory flood insurance purchase requirements. As a result, there are no flood insurance rate maps for the city of Glendale, and Glendale is not listed in FEMA’s Community Rating System.
The Community Rating System (CRS) is a system for crediting communities that implement measures to protect the natural and beneficial functions of their floodplains, as well as managing their erosion hazard.] Although, there are no FIRM maps for the city, and Glendale is not currently listed in FEMA’s CRS of cities, the City of Glendale has participated as a regular member in the NFIP since August 31, 1984 (City ID No. – 065030). Since the City is a participating member of the NFIP, flood insurance is available for individuals to purchase voluntarily. There is, however, a 30-day wait period after the policy is issued before the coverage becomes effective.
Since these analyses were conducted, however, there has been substantial development in the hills of Glendale, increasing runoff into the city’s storm drains and flood-conveyance system. The studies also did not consider the impacts that debris flows could have on the city. During the past 80 years, the Los Ang e l e s C o u n t y D e p a r t m e n t o f P u b l i c W o r k s (LACDPW) and the US Army Corps of Engineers have constructed several detention or debris basins in the San Gabriel Mountains, in or above Glendale, including debris basins in Cooks, Dunsmore, Shields, Eagle, Pickens and Hall Beckley Canyons. At least three other debris basins have been built in the Verdugo Mountains, above the populated areas of the city. The Local Hazard Mitigation Plan Section 8: Floods
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LACDPW also has made channel alterations consisting primarily of concrete side-slopes and linings for most of the major channels in the area. These flood control structures are presently owned and operated by the LACDPW, which has jurisdiction over the watercourses in the Glendale area, as well as the regional flood control system in the Los Angeles County.
All of these structures help regulate flow in the Verdugo Channel, holding back some of the flow during intense rainfall periods that could otherwise overwhelm the storm drain system in the area.
These storm drain facilities generally provide the city with adequate protection from a major storm except some isolated minor localized inundation. This type of localized inundation may mean that on major storms, a portion of the street may be flooded but the water level will be contained within the curbs. No flooding of private properties occurs unless there is a backup of local storm drains.
Localized Flooding: One area in the city that may sporadically flood is at the terminus of Woodland Avenue. This street was cut with the construction of the Verdugo Wash, and is now a dead-end residential street that is serving only 12 residential homes. A lateral of the Verdugo Wash Channel was also constructed which terminated at the terminus of Woodland Avenue. Because of grade, three (3) 36-inch flap gates were installed at the end of that lateral.
Under severe storm conditions, the flap gates close and runoff from the street is retained within the street temporarily until the flow can be taken into the channel.
Inundation due to Catastrophic Failure of Water Storage Structures:
Loss of life and damage to structures, roads, and utilities may result from a dam failure.
Economic losses can also result from a lowered tax base and lack of utility profits. These effects would certainly accompany the failure of one of the major dams in the city of Glendale.
There are seven dams in the Glendale area that fall under State jurisdiction. These dams are owned by the city of Glendale and retain small reservoirs in the Verdugo Mountains and San Rafael Hills. From west to east, they include the 10th and Western, Brand Park, and Diederich dams in the Verdugo Mountains, and the East Glorietta, Chevy Chase 1290, Glenoaks and Chevy Chase 980 dams in the San Rafael Hills. Areas in Glendale within the dam inundation Local Hazard Mitigation Plan Section 8: Floods
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areas identified by the State are shown on Map 8-3 (and Plate H-10).
There are several other, smaller debris basins in the Glendale area that are not subject to State regulations because they are too small. These debris basins, and other flood control improvements, such as canals, culverts, and levees, may crack and suffer structural damage during an earthquake, especially in areas prone to ground failure, such as that due to liquefaction or slope instability. These facilities could pose an inund ation hazard to areas downstream if they contain water at the time of the seismic event, or if they are not repaired prior to the next winter storm season.
There are thirteen steel water storage tanks in the city of Glendale. Tanks located near the fault hazard management zones (identified in Section 6 of this report, see Plate H-4) are especially vulnerable to rupture due to ground deformation, strong ground shaking and even surface fault rupture. While most water tanks in the Glendale area are not located near fault management zones, three tanks near the base of the San Gabriel Mountains are located within the State mandated Alquist-Priolo Earthquake Fault Zone for the Sierra Madre Fault.
Because these water tanks have a heightened risk of rupturing catastrophically during an earthquake on the Sierra Madre Fault, their inundation paths should be identified to evaluate whether or not habitable structures are located within the floodway. The evaluation should also address whether these water reservoirs are self-contained. In the event of a catastrophic breakage, will the water be contained within the site, or will it be discharged to a storm drain or channel or will it pose a hazard to properties downstream? Because the entire city of Glendale is susceptible to strong seismic ground motion, all water tanks should incorporate new earthquake resistant designs, including flexible pipe joints.
Many water tanks have already been retrofitted with these improvements; however, the Glendale Heights, Allen, San Luis Rey, and especially Cooks Canyon water tanks still need to be updated.
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Map 8-3: Dam Inundation Areas in the City of Glendale
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Vulnerability Assessment:
Vulnerability assessment is the second step of flood-hazard assessment. It combines the flood prone areas identified previously with an inventory of the property within those areas.
Understanding the population and property exposed to this hazard can assist in reducing risk and preventing loss from future events. Because site-specific inventory data and inundation levels are not available for Glendale (according to FEMA there are no flood-prone areas in the city), calculating the community’s vulnerability to flood events is difficult.
Typically, vulnerability assessments of flooding hazards involve assessing the amount of property in the floodplain, as well as the type and value of structures on those properties.
Once that is done, then a working estimate for potential flood losses can be calculated. The HAZUS software has a component to estimate losses due to flooding. Input to the program can include FEMA flood inundation zones, or site-specific engineering studies of flood potential prepared by others rather than FEMA. Since there are no FEMA maps available for Glendale, nor are there more recent and city-specific studies that identify potential flooding areas, this loss estimation analysis was not conducted for this report. Should data be developed in the future to more fully map this hazard, loss estimation analyses based on that mapping can then be conducted.
Community Flood Issues:
What is Susceptible to Damage During a Flood Event?
The largest impact on communities from flood events is the loss of life and property. During certain years, property losses resulting from flood damage are extensive. Property loss from floods strikes both private and public property. Although there has been no significant flooding in Glendale since at least 1969, as described above, localized flooding does occur sporadically. Furthermore, storm damage in the form of drips into structures, amounting to considerable amount of money in the form of repairs, have been reported as recently as with the storms of 2005.
Property Loss Resulting from Flooding Events:
The type of property damage caused by flood events depends on the depth and velocity of Local Hazard Mitigation Plan Section 8: Floods
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the floodwaters. Faster moving floodwaters can wash buildings off their foundations and sweep cars downstream. Pipelines, bridges, and other infrastructure can be damaged when high waters combine with flood debris. Extensive damage can be caused by basement flooding and landslide damage related to soil saturation from flood events. Most flood damage is caused by water saturating materials susceptible to loss (i.e., wood, insulation, wallboard, fabric, furnishings, floor coverings, and appliances). In many cases, flood damage to homes renders them unlivable.
Risk Analysis:
Risk analysis is the third and most advanced phase of a hazard assessment. It builds upon the hazard identification and vulnerability assessment. A flood risk analysis for the city of Glendale should include two components: 1) the life and value of property that may incur losses from a flood event (defined through the vulnerability assessment); and 2) the number and type of flood events expected to occur over time. Within the broad components of a risk analysis, it is possible to predict the severity of damage from a range of events. Flow velocity models can assist in predicting the amount of damage expected from different magnitudes of flood events.
The data used to develop these models is based on hydrological analysis of landscape features. Changes in the landscape, often associated with human development, can alter the flow velocity and the severity of damage that can be expected from a flood event. Using GIS technology and flow velocity models, it is possible to map the damage that can be expected from flood events over time. It is also possible to pinpoint the effects of certain flood events on individual properties. At the time of publication of this Plan, data was insufficient to conduct a risk analysis for flood events in the city of Glendale. However, the current mapping projects will result in better data that will assist in understanding risk. This Plan includes recommendations for building partnerships that will support the development of a flood risk analysis in the City of Glendale.
Manufactured Homes:
Statewide, the 1996 floods destroyed 156 housing units. Of those units, 61 percent were Local Hazard Mitigation Plan Section 8: Floods
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mobile homes and trailers. Many older manufactured home parks are located in floodplain or low-lying areas. Manufactured homes have a lower level of structural stability than stick- built homes and must be anchored to provide additional structural stability during flood events (and for earthquake preparedness, also). Because of confusion in the late 1980s resulting from multiple changes in NFIP regulations, there are some communities that do not actively enforce anchoring requirements.
Business/Industry:
Storm-flooding events impact businesses by damaging property and by interrupting business. Flood events can cut off customer access to a business as well as close a business for repairs. Roof leaks can impact the contents; in extreme cases, leaks can cause damage to sensitive electrical equipment, with the potential to cause the affected business thousands of dollars in material losses and potential loss of revenue. A quick response to the needs of businesses affected by flood events can help a community maintain economic vitality in the face of flood damage. Responses to business damages can include funding to assist owners in elevating or relocating flood-prone business structures, and loans to make building improvements, such as new roofs.
Public Infrastructure:
Publicly owned facilities are a key component of daily life for all citizens of Los Angeles County, including Glendale residents. Damage to public water and sewer systems, transportation networks, flood control facilities, emergency facilities, and offices can hinder the ability of the government to deliver services. Government can take action to reduce risk to public infrastructure from flood events, as well as craft public policy that reduces risk to private property from flood events.
Roads:
During natural hazard events, or any type of emergency or disaster, dependable road connections are critical for providing emergency services. Roads systems in the city of Glendale are maintained by multiple jurisdictions. Federal, State, county, and city governments all have a stake in protecting roads from flood damage. Road networks often Local Hazard Mitigation Plan Section 8: Floods
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traverse floodplains and floodway areas. Transportation agencies responsible for road maintenance are typically aware of roads at risk from flooding.
Bridges:
Bridges are key points of concern during flood events because they are important links in road networks, river crossings, and they can be obstructions in watercourses, inhibiting the flow of water during flood events. Scour at highway bridges involves sediment-transport and erosion processes that cause streambed material to be removed from the bridge vicinity.
Nationwide, several catastrophic collapses of highway and railroad bridges have occurred due to scouring and a subsequent loss of support of foundations. This has led to a nationwide inventory and evaluation of bridges (Richardson and others, 1993).
Scour processes are generally classified into separate components, including pier scour, abutment scour, and contraction scour. Pier scour occurs when flow impinges against the upstream side of the pier, forcing the flow in a downward direction and causing scour of the streambed adjacent to the pier. Abutment scour happens when flow impinges against the abutment, causing the flow to change direction and mix with adjacent main-channel flow, resulting in scouring forces near the abutment toe. Contraction scour occurs when flood- plain flow is forced back through a narrower opening at the bridge, where an increase in velocity can produce scour. Total scour for a particular site is the combined effects from all three components. Scour can occur within the mai n c h a n n e l , o n t h e f l o o d p l a i n , o r b o t h .
While different materials scour at different rates, the ultimate scour attained for different materials is similar and depends mainly on the duration of peak stream flow acting on the material (Lagasse and others, 1991).
The State of California participates in the bridge scour inventory and evaluation program and a state-designated inspector must inspect all state, county, and city bridges every two years. The inspections are rigorous, looking at everything from seismic capability to erosion and scour. The bridges in the city of Glendale are State, county, city, or privately owned. To date, we have not found any records to indicate that the bridges in the Glendale area have been evaluated. Nevertheless, since the Verdugo Wash is channelized in the city, the Local Hazard Mitigation Plan Section 8: Floods
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potential for bridge scour to occur along the Verdugo Wash is considered low to nil. The most significant, although unlikely concern regarding bridge scour is if unusually high surface water flows in the Sycamore and Scholl Canyons were to reach the Glendale (2) Freeway, impacting the bridges at Chase Drive and Glenoaks Boulevard. Privately owned bridges are not inspected, so those bridges extending across unlined creeks could be at risk of failure due to scour.
Storm Water Systems:
As indicated above, drainage problems are kno w n t o o c c u r s p o r a d i c a l l y i n s o m e s p e c i f i c areas of Glendale. However, the City does not consider these drainage issues more than a nuisance and has pumping equipment to deal with flooding in these low spots when necessary.
Inadequate maintenance can also contribute to the flood hazard in urban areas. As long as the City conducts a regular inspection of culverts and storm drains to remove debris that may obstruct the flow of water during storms, most areas should not be impacted by flooding.
Water/Wastewater Treatment Facilities:
The city of Glendale is a part of the Sanitation Districts of Los Angeles County. The Sanitation Districts are a confederation of independent special districts serving about 5 million people in Los Angeles County. There are no wastewater treatment facilities in Glendale.
Water Quality:
Environmental quality problems include bacteria, toxins, and pollution. “Out of sight, out of mind” has traditionally been a common approach to dealing with trash, sediment, used motor oil, unused paint and thinner, and other hazardous substances that people dump into the sewer or storm drains. What we often forget is that these substances eventually make their way into the rivers and oceans, where they can sicken surfers and swimmers, and endanger wildlife. The Clean Water Act of 1972 originally established the National Pollutant Discharge Elimination System (NPDES) to control wastewater discharges from various Local Hazard Mitigation Plan Section 8: Floods
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industries and wastewater treatment plants, known as “point sources.” Point sources are defined by the EPA as discrete conveyances such as pipes or direct discharges from businesses or public agencies. Then, in 1987, the Water Quality Act amended the NPDES permit system to include “nonpoint source” pollution (NPS pollution). NPS pollution refers to the introduction of bacteria, sediment, oil and grease, heavy metals, pesticides, fertilizers and other chemicals into our rivers, bays and oceans from less defined sources. These pollutants are washed away from roadways, parking lots, yards, and other areas by rain and dry-weather urban runoff, entering the storm drains, and ultimately the area’s streams, bays and ocean. NPS pollution is now thought to account for most water quality problems in the United States. Therefore, strict enforcement of this program at the local level, with everybody doing his or her part to reduce NPS pollution, can make a significant difference.
The National Pollutant Discharge Elimination System (NPDES) permit program controls water pollution by regulating point and nonpoint sources that discharge pollutants into waters of the United States. The City of Glendale is a member of the Los Angeles County Storm water Program. This program regulates and controls storm water and urban runoff into the Los Angeles River, San Gabriel River, Santa Clara River, tributaries to these rivers, and ultimately, the Pacific Ocean. The Los Angeles County Storm water Program is the local enforcer of the NPDES program. In the Glendale Area, NPDES permits are filed with the California Regional Water Quality Control Board, Los Angeles Region. This permit was required by all counties with a storm drain system that serves a population of 100,000 or more. On October 29, 1999, Phase II of NPDES was signed into law. Under this phase of NPDES, areas with 50,000 or more residents, and construction sites one acre or more in size, must file for and obtain an NPDES permit. Under NPDES, the local regulator is responsible for the following control measures:
x Public education and outreach on storm water impacts, x Public involvement/participation,
x Illicit discharge detection and elimination,
x Construction of site storm water runoff control,
x Post-construction storm water management in new development and redevelopment, and
x Pollution prevention/good housekeeping for municipal operations.
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The NPDES permit area that includes Glendale is 3,100 square miles in area, with a population of 11.4 million. In conformance with the Federal requirements listed above, one of the major tasks of the Los Angeles County Storm water Program is to educate the local population about keeping the water that flows into our rivers and ocean clean by eliminating discharges of hazardous materials into storm drains and other point sources. Signs are typically painted by storm drains that drain to the local rivers and ultimately into the Pacific Ocean to encourage people from not disposing motor oil or other potentially hazardous substances into the drains.
Existing Flood Mitigation Activities:
Flood mitigation activities listed here include current mitigation programs and activities that are being implemented by the City of Glendale agencies or organizations.
The City of Glendale uses building codes, zoning codes, and various planning strategies to address the goals which aim at restricting development in areas of known hazards and applying the appropriate safeguards.
Acquisition and Protection of Open Space in the Floodplain:
Current efforts to increase public open space in the southern California area been paired with the need to restore and preserve natural systems that provide wildlife habitat and help to mitigate flood events. Public parks and publicly owned open spaces can provide a buffer between flood hazards and private property.
Water Districts:
Many water districts in the region are in the process of replacing old cast iron pipes with more ductile iron pipes, which will be more resilient in disaster situations. During a disaster, water districts in the region work are committed to working together to provide water to the area’s residents as soon as possible in the event that the water distribution system fails locally.
For example, Glendale’s Department of Water and Power has built inter-ties with the Metropolitan Water District for emergency situations.
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Storm water Systems:
There are several surface water management providers in the county that manage water quality and storm water runoff from new development. The primary one and the one that provides flood control services for the city of Glendale is the Los Angeles County Department of Public Works.
Flood Management Projects:
Flood management structures can assist in regulating flood levels by adjusting water flows upstream of flood-prone areas. The main flood control systems in the Glendale area include the Verdugo Wash Flood Control Channel and Sycamore Canyon Channel. In addition, there are several detention or debris basins in the San Gabriel Mountains, in or above Glendale that provide flood protection.
Verdugo Wash Flood Control Channel:
The city of Glendale is primarily served by the Verdugo Wash Flood Control Channel. This Channel was designed for a 100-year capital storm to carry the storm water run-off from the hillsides at the northern portion of the city (in the La Crescenta area), and outlets into the Los Angeles River. Other tributaries of the Verdugo Wash include: Halls Canyon Channel, Pickens Canyon Channel, Eagle Shields Canyon Channel, Cooks Canyon Channel and the Dunsmuir Canyon Channel. A debris basin was also constructed across the Verdugo Wash Channel downstream from all the tributary channels to filter debris that could potentially clog the channel and reduce its capacity.
Sycamore Canyon Channel:
The eastern portion of the city is served by the Sycamore Canyon Channel. This channel was built during the 1930s. Although many developments have occurred within its drainage area, it is generally adequate for storm water protection, except for a small portion of the “Adams Hill Area,” where there is a dip on Cottage Grove Avenue, between Palmer Street and Green Street. This dip acts as drainage channel, and during heavy rains, this dip may be subjected to minor flooding. However, private properties are not adversely affected.
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Community Issues Summary:
Flooding issues in Glendale are considered minor, however, recent storms have shown that storm damages to structures and businesses can cost thousands if not millions of dollars to repair. In most cases, these loss estimates do not even include lost revenue due to business interruption.
The City of Glendale works to address its localized flooding problems as they arise. However, given that some areas in Glendale appear to be more susceptible to flooding issues, due in great part to urban run-off and modification of the natural environment, proactive measures that address the issues before flooding occurs are being taken. Some of those measures are the building codes, zoning codes, and various planning strategies to restrict development in areas of known hazards. Also, with assistance of the U.S. Geological Survey (USGS) in cooperation with the National Oceanic and Atmospheric Association (NOAA) conducts detailed monitoring of precipitation, runoff, and erosion. Three monitoring sites have been established in Dunsmore Canyon to provide information from the NOAA’s National Weather Service. This data is used to issue warnings, make decisions and to advance the understanding of post-fire runoff, erosion, and the debris-flow generation process.
Monitoring equipment at the sites measures rainfall, flow stage, and soil moisture.
Solar/battery powered video cameras are used to provide a visual record of the flow and channel change. During rain events, video is recorded at four frames per second. Still images from the cameras are transmitted to the internet every day at noon and every five minutes during rain events.
As with every emergency event, the City of Glendale takes advantage of all its resources in order to protect its citizens, property, and the environment from all hazards.
Flood Mitigation Action Items
The flood mitigation action items provide direction on specific activities that organizations and residents in the city of Glendale can undertake to reduce risk and prevent loss from flood events. Each action item is followed by ideas for implementation, which can be used by the Local Hazard Mitigation Plan Section 8: Floods
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steering committee and local decision makers in pursuing strategies for implementation.
Short Term – Flood #l: Analyze each repetitive flood property within the City of Glendale and identify feasible mitigation options.
Ideas for Implementation:
x Identify appropriate and feasible mitigation activities for identified repetitive flood properties. Funding may be available through FEMA's Hazard Mitigation Grant and Flood Mitigation Assistance Programs and the Pre-disaster Mitigation Program. x Contact repetitive loss property owners to discuss mitigation opportunities and determine interest should future project opportunities arise. x Explore options for incentives to encourage property owners to engage in mitigation.
Coordinating Organization: Hazard Mitigation Plan Steering Group Timeline: 1-2 years
Plan Goals Addressed: Protect Life and Property, Partnerships and Implementation
Constraints: Pending Funding and Available Personnel Short Term – Flood #2: Recommend revisions to requirements for development within the floodplain, where appropriate.
Ideas for Implementation:
x Evaluate elevation requirements for new residential and nonresidential structures in the unincorporated floodplain area.
x Explore raising the base elevation requirement for new residential construction to two or three feet above base flood elevation, or greater. An increased elevation standard is one activity the county can engage in to receive credit from the NFIP Community Rating System Program.
x Identify opportunities to upgrade Federal Insurance Rate Map and arrange for Cooperative Technical Partnership mapping upgrades for select areas. x Identify alternatives to reduce development in the floodplain.
Coordinating Organization: City of Glendale Departments of Public Works and Community Development, County Department of
Transportation and Development, County Geographic
Information Services, Water Environment Services, L.A.
County Flood Control District
Timeline: 2 y e a r s
Plan Goals Addressed: Protect Life and Property
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Short Term – Flood #3: Provide notification capability to 100% of Glendale residents.
Ideas for Implementation:
x Coordinate with appropriate organizations to evaluate the need for more stream gauges. Distribute information regarding flooding to the general public efficiently.
Coordinating Organization: City of Glendale Emergency Management Office, City of Glendale Management Services Department, County
Emergency Management, County Public and
Government Relations.
Timeline: 2 y e a r s
Plan Goals Addressed: Protect Life and Property, Emergency Services Constraints: Pending Funding and Available Personnel Long Term – Flood #l: Enhance data and mapping for floodplain information within the county and identify and map flood-prone areas outside of designated floodplains.
Ideas for Implementation:
x Apply for FEMA's cooperative technical partnership using the 2-foot contour interval floodplain mapping data acquired by the City of Glendale GIS. x Use WES inventory and mapping data to update the flood-loss estimates for the city of Glendale.
x Encourage the development of floodplain maps for all local streams not currently mapped on Flood Insurance Rate Maps or county maps, with special attention focused on mapping rural and unincorporated areas. The maps should show the expected frequency of flooding, the level of flooding, and the areas subject to inundation. The maps can be used for planning, risk analysis, and emergency management.
Coordinating Organization: County Geographic Information Services, County Department of Transportation and Development, Water
Environment Services
Timeline: 3 years (as funding allows)
Plan Goals Addressed: Protect Life and Property
Constraints: Pending Funding and Available Personnel Long Term – Flood #2: Encourage development of acquisition and management strategies to preserve open space for flood mitigation, fish habitat, and water quality in the floodplain.
Ideas for Implementation:
x Develop a comprehensive strategy for acquiring and managing floodplain open space in the City of Glendale.
x Explore funding for property acquisition from federal (e.g. FEMA Hazard Mitigation Grant Program), state, regional, and local governments, as well as private and non- Local Hazard Mitigation Plan Section 8: Floods
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profit organizations, trails programs, fish programs as well as options for special appropriations.
x Develop a regional partnership between flood mitigation, fish habitat, and water quality enhancement organizations/programs to improve educational programs. x Identify sites where environmental restoration work can benefit flood mitigation, fish habitat, and water quality.
x Work with landowners to develop flood management practices that provide healthy fish habitat.
x Identify existing watershed education programs and determine which programs would support a flood education component.
Coordinating Organization: County Department of Transportation and Development, Water Environment Services
Timeline: 5 y e a r s
Plan Goals Addressed: Natural Systems, Protect Life and Property Constraints: Pending Funding and Available Personnel Long Term – Flood #3: Identify surface water drainage obstructions in the city of Glendale.
Ideas for Implementation:
x Map culverts in the city.
x Prepare an inventory of culverts that historically create flooding problems and target them for retrofitting.
x Prepare an inventory of major urban drainage problems and identify causes and potential mitigation actions for urban drainage problem areas.
Coordinating Organization: County Roads Division, Water Environment Services, County Geographic Information Systems
Timeline: 5 y e a r s
Plan Goals Addressed: Protect Life and Property
Constraints: Pending Funding and Available Personnel Long Term - Flood #4: Establish a framework to compile and coordinate surface water management plans and data throughout the city.
Ideas for Implementation:
x Develop surface water management plans for areas that are not currently within surface water management plan boundaries.
Coordinating Organization: Water Environment Services, County Planning Division, Geographic Information Systems
Timeline: 5 y e a r s
Plan Goals Addressed: Protect Life and Property, Partnerships and Local Hazard Mitigation Plan Section 8: Floods
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Implementation
Constraints: Pending Funding and Available Personnel
Flood Resource Directory
The following resource directory lists the resources and programs that can assist county communities and organizations. The resource directory will provide contact information for local, county, regional, State and Federal programs that deal with natural hazards. For additional information, refer to Appendix A.
County Resources:
Los Angeles County Public Works Department
900 S. Fremont Ave.
Alhambra, CA 91803
Ph: 626-458-5100
Sanitation District of Los Angeles County
1955 Workman Mill Road
Whittier, CA 90607
Ph: 562-699-7411 x2301
State Resources:
Governor’s Office of Emergency Services (OES)
P.O. Box 419047
Rancho Cordova, CA 95741-9047
Ph: 916 845- 8911
Fx: 916 845- 8910
California Resources Agency
1416 Ninth Street, Suite 1311
Sacramento, CA 95814
Ph: 916-653-5656
California Department of Water Resources (DWR)
1416 9th Street
Sacramento, CA 95814
Ph: 916-653-6192
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California Department of Conservation: Southern California Regional Office 655 S. Hope Street, #700
Los Angeles, CA 90017-2321
Ph: 213-239-0878
Fx: 213-239-0984
Federal Resources and Programs:
Federal Emergency Management Agency (FEMA)
FEMA provides maps of flood hazard areas, various publications related to flood mitigation, funding for flood mitigation projects, and technical assistance. FEMA also operates the National Flood Insurance Program. FEMA' s mission is to reduce loss of life and property and protect the nation’s critical infrastructure from all types of hazards through a comprehensive, risk-based, emergency management program of mitigation, preparedness, response and recovery.
Federal Emergency Management Agency, Region IX
1111 Broadway, Suite 1200
Oakland, CA 94607
Ph: 510-627-7100
Fx: 510-627-7112
Federal Emergency Management Agency, Mitigation Division 500 C Street, S.W.
Washington, D.C. 20472
Ph: 202-566-1600
FEMA' s List of Flood Related Websites
This site contains a long list of flood related Internet sites from “American Heritage Rivers" to "The Weather Channel" and is a good starting point for flood information on the Internet.
Contact: Federal Emergency Management Agency, Phone: (800) 480-2520 Website: http://www.fema.gov/nfip/related.htm
National Flood Insurance Program (NFIP)
In southern California, many cities lie within flood zones as defined in FEMA Flood Maps.
The City of Glendale is not a community within a designated flood zone. Nevertheless, flood Local Hazard Mitigation Plan Section 8: Floods
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insurance is available to citizens in communities that adopt and implement NFIP building standards. The standards are applied to development that occurs within a delineated floodplain, a drainage hazard area, and properties within 250 feet of a floodplain boundary.
These areas are depicted on federal Flood Insurance Rate Maps available through the county.
National Floodplain Insurance Program (NFIP)
500 C Street, S.W.
Washington, D.C. 20472 Ph: 202-566-1600
Other National Resources:
The Floodplain Management Association
The Floodplain Management website was established by the Floodplain Management Association (FMA) to serve the entire floodplain management community. It includes full- text articles, a calendar of upcoming events, a list of positions available, an index of publications available free or at nominal cost, a list of associations, a list of firms and consultants in floodplain management, an index of newsletters dealing with flood issues (with hypertext links if available), a section on the basics of floodplain management, a list of frequently asked questions (FAQs) about the Website, and a catalog of Web links.
Floodplain Management Association
P.O. Box 50891
Sparks, NV 89435-0891
Ph: 775-626-6389
Fx: 775-626-6389
The Association of State Floodplain Managers
The Association of State Floodplain Managers is an organization of professionals involved in floodplain management, flood hazard mitigation, the National Flood Insurance Program, and flood preparedness, warning, and recovery. ASFPM fosters communication among those responsible for flood hazard activities, provides technical advice to governments and other entities about proposed actions or policies tha t w i l l a f f e c t f l o o d h azards, and encourages flood hazard research, education, and training. The ASFPM Web site includes information on how to become a member, the organization’s constitution and bylaws, directories of officers and committees, a publications list, information on upcoming conferences, a history of the association, and other useful information and Internet links.
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Contact: The Association of State Floodplain Managers
Address: 2809 Fish Hatchery Road, Madison, WI 53713 Phone: (608) 274-0123 Website: http://www.floods,org
National Weather Service
The National Weather Service provides flood watches, warnings, and informational statements for rivers in the City of Glendale.
National Weather Service
520 North Elevar Street
Oxnard, CA 93030
Ph: 805-988- 6615
Office of Hydrology, National Weather Service
The National Weather Service s Office of Hydrology (OH) and its Hydrological Information Center offer information on floods and other aquatic disasters. This site offers current and historical data including an archive of past flood summaries, information on current hydrologic conditions, water supply outlooks, an Automated Local Flood Warning Systems Handbook, Natural Disaster Survey Reports, and other scientific publications on hydrology and flooding.
National Weather Service, Office of Hydrologic Development 1325 East West Highway, SSMC2
Silver Spring, MD 20910
Ph: 301-713-1658
Fx: 301-713-0963
National Resources Conservation Service (NRCS), US Department of Agriculture NRCS provides a suite of federal programs designed to assist state and local governments and landowners in mitigating the impacts of flood events. The Watershed Surveys and Planning Program and the Small Watershed Program provide technical and financial assistance to help participants solve natural resource and related economic problems on a watershed basis. The Wetlands Reserve Program and the Flood Risk Reduction Program provide financial incentives to landowners to put aside land that is either a wetland resource, or that experiences frequent flooding. The Emergency Watershed Protection Program (EWP) provides technical and financial assistance to clear debris from clogged waterways, restore vegetation, and stabilizing riverbanks. The measures taken under EWP must be Local Hazard Mitigation Plan Section 8: Floods
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environmentally and economically sound and generally benefit more than one property.
National Resources Conservation Service
14th and Independence Ave., SW, Room 5105-A
Washington, DC 20250
Ph: 202-720-7246
Fx: 202-720-7690
USGS Water Resources
This web page offers current US water news; extensive current (including real-time) and historical water data; numerous fact sheets and other publications; various technical resources; descriptions of ongoing water survey programs; local water information; and connections to other sources of water information.
USGS Water Resources
6000 J Street Placer Hall
Sacramento, CA 95819-6129
Ph: 916-278-3000
Fx: 916-278-3070
Bureau of Reclamation
The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. The Bureau provides leadership and technical expertise in water resources development and in the efficient use of water through initiatives including conservation, reuse, and research. It protects the public and the environment through the adequate maintenance and appropriate operation of Reclamation's facilities and manages Reclamation's facilities to fulfill water user contracts and protect and/or enhance conditions for fish, wildlife, land, and cultural resources.
Mid Pacific Regional Office
Federal Office Building
2800 Cottage Way
Sacramento CA 95825-1898
Ph: 916- 978-5000
Fax 916- 978-5599
http://www.usbr.gov/
Army Corps of Engineers
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The Corps of Engineers administers a permit program to ensure that the nation’s waterways are used in the public interest. Any person, firm, or agency planning to work in waters of the United States must first obtain a permit from the Army Corps of Engineers. The Corps is responsible for the protection and development of the nation’s water resources, including navigation, flood control, energy production through hydropower management, water supply storage and recreation.
US Army Corps of Engineers
P.O. Box 532711
Los Angeles, CA 90053- 2325
Ph: 213-452- 3921
American Public Works Association
2345 Grand Boulevard, Suite 500
Kansas City, MO 64108-2641
Ph: 816-472-6100
Fx: 816-472-161
Publications:
NFlP Community Rating System Coordinator’s Manual
Indianapolis, IN.
This informative brochure explains how the Community Rating System works and what the benefits are to communities. It explains in detail the CRS point system, and what activities communities can pursue to earn points. These points then add up to the "rating" for the community, and flood insurance premium discounts are calculated based upon that "rating." The brochure also provides a table on the percent discount realized for each rating (1-10).
Instructions on how to apply to be a CRS community are also included.
Contact: NFIP Community Rating System
Phone: (800) 480-2520 or (317) 848-2898 - Website: http://www.fema.gov/nfip/crs Floodplain Management: A Local Floodplain Administrator’s Guide to the NFlP This document discusses floodplain processes and terminology. It contains floodplain management and mitigation strategies, as well as information on the NFIP, CRS, Community Assistance Visits, and floodplain development standards.
Contact: National Flood Insurance Program Phone: (800) 480-2520 Local Hazard Mitigation Plan Section 8: Floods
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Website: http://www.fema,gov/nfip/
Flood Hazard Mitigation Planning: A Community Guide, (June 1997).
Massachusetts Department of Environmental Management.
This informative guide offers a 10-step process for successful flood hazard mitigation. Steps include: map hazards, determine potential damage areas, take an inventory of facilities in the flood zone, determine what is or is not being done about flooding, identify gaps in protection, brainstorm alternatives and actions, determine feasible actions, coordinate with others, prioritize actions, develop strategies for implementation, and adopt and monitor the plan.
Contact: Massachusetts Flood Hazard Management Program Phone: (617) 626-1250 Website: http://www.magnetstate.ma.us/dem/programs/mitigate Reducing Losses in High Risk Flood Hazard Areas: A Guidebook for Local Officials, (February 1987), FEMA-116.
This guidebook offers a table on actions that communities can take to reduce flood losses. It also offers a table with sources for floodplain mapping assistance for the various types of flooding hazards. There is information on various types of flood hazards with regard to existing mitigation efforts and options for action (policy and programs, mapping, regulatory, non-regulatory). Types of flooding which are covered include alluvial fan, areas behind levees, areas below unsafe dams, coastal flooding, flash floods, fluctuating lake level floods, ground failure triggered by earthquakes, ice jam flooding, and mudslides.
Contact: Federal Emergency Management Agency Phone: (800) 480-2520 Website: http://www.fema,gov
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Local Hazard Mitigation Plan Section 9: Landslides
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SECTION 9: LANDSLIDES
Table of Contents
Why are Landslides a Threat to City of Glendale? 9-3 L a n d s l i d e H a z a r d A s s e s s m e n t 9 - 1 3 C o m m u n i t y L a n d s l i d e I s s u e s 9 - 1 7 What is Susceptible to Landslides? 9-17
L a n d s l i d e M i t i g a t i o n A c t i o n I t e m s 9 - 2 2 L a n d s l i d e R e s o u r c e D i r e c t o r y 9 - 2 3 P u b l i c a t i o n s : 9 - 2 5
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Map 9-1: Landslide Inventory Map of Pasadena Quadrangle .
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Why are Landslides a Threat to City of Glendale?
Landslides are a serious geologic hazard in almost every state in America. Nationally, landslides cause 25 to 50 deaths each year. The best estimate of direct and indirect costs of landslide damage in the United States ranges between $1 and $2 billion annually. In California, landslides are a significant problem, in part because of the region’s seismic activity, and in part because the region is underlain by weak soils and rocks, especially when saturated or in burn scarred areas. Some landslides result in private property damage, whereas other landslides impact transportation corridors, fuel and energy conduits, and communication facilities. They can also pose a serious threat to human life.
The San Gabriel Mountains are located in the central part of the Transverse Ranges, where they rise abruptly to heights of more than 7,000 feet above the valley floor (several peaks are more than 9,000 feet high and Mount Baldy is the highest at 10,064 feet). Bounded by the San Andreas Fault system on the north and the Sierra Madre Fault zone on the south, the mountains are essentially a large block of the Earth’s crust that has been squeezed up and thrust over the valley floor by north-south compression along the Big Bend portion of the San Andreas tectonic plate boundary. The current rate of uplift, in the context of geologic time, is one of the fastest in the world.
The steep southern flank of the San Gabriel Mountains is deeply incised by gorges and canyons that drain south into the La Cañada Valley, where they have been channelized, conveying their flows south to Verdugo Wash. The three canyons that are located mostly within city of Glendale limits include Ward, Dunsmore, and Cooks. Several other streams draining the San Gabriel Mountains are also channelized through the La Crescenta area and into the northern portion of Glendale; these include the Eagle Canyon, Pickens, Hills and Winery Canyon channels (see Plate H-1 in Appendix H). Nearly all the tributaries flowing north and east out of the Verdugo Mountains and westerly out of the San Rafael Hills also empty into Verdugo Wash. South of the mountains, Verdugo Wash turns to the west- southwest and joins the Los Angeles River near the junction of Highway 134 with the 5 Freeway (Interstate 5). Drainage from the southwestern slope of the Verdugo Mountains flows directly across the alluvial fan and into the Los Angeles River. As discussed further in Local Hazard Mitigation Plan Section 9: Landslides
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Section 8 Verdugo Wash has been confined to a man-made channel through most of Glendale to reduce the potential for it to flood the city.
Nearly half of the land in Glendale consists of steep hillslopes and rugged mountains. These areas have for the most part been preserved in their near natural state, while most of the development in the city occurs in the flat to gently sloping alluvial surfaces at the base of the mountains. However, some development (primarily residential) is present in and adjacent to steep hillsides. These areas include the canyons within the Verdugo Mountains and the San Rafael Hills, and the alluvial fans situated at the front of the San Gabriel and Verdugo Mountains. Such areas are locally vulnerable to slope instability, particularly in winters of heavy rainfall and in winters following wildfires.
What is a Landslide?
Landslides are downslope movements of relatively large landmasses, either as nearly intact bedrock blocks, or as jumbled mixes of bedrock blocks, fragments, debris, and soil.
Landslides are a type of “mass wasting” which denotes any down slope movement of soil and rock under the direct influence of gravity. The term “landslide” encompasses events such as rock falls, topples, slides, spreads, and flows, and in general, landslides can be broken down into two categories: rapidly moving (generally known as debris flows) and slow moving.
Rapidly moving landslides or debris flows pose the greatest risk to human life, and people living in or traveling through areas prone to rapidly moving landslides are at increased risk of serious injury. Slow moving landslides can cause significant property damage but are less likely to result in serious human injuries.
Geologists also describe the type of movement of a landslide as either (1) translational (where movement occurs along a flat surface), (2) rotational (where sliding material moves along a curved surface) or (3) wedge (where movement occurs on a wedge-shaped block formed by intersecting planes of weakness, such as fractures, faults and bedding). The size of a landslide usually depends on the geology and the initial cause of the landslide. Landslides vary greatly in their volume of rock and soil, the length, width, and depth of the area affected, frequency of occurrence, and speed of movement. Slow-moving landslides can occur on relatively gentle slopes and can cause significant property damage but are far less likely to Local Hazard Mitigation Plan Section 9: Landslides
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result in serious injuries than rapidly moving landslides. Rotational and translational slides are generally slow moving and can be deep; whereas wedge failures generally occur suddenly and are shallow. Slumps are small rotational slides that are generally shallow.
Landslides can be initiated by rainfall, earthquakes, volcanic activity, changes in ground water, disturbance and change of a slope by man-made construction activities, or any combination of these factors. Landslides can also occur underwater, causing tidal waves and damage to coastal areas. The potential for slope failure is dependent on many factors, including slope height, slope steepness, shear strength and orientation of the underlying geologic unit, as well as moisture content. For example, water can increase the plasticity of weak clays lining joints or shears, forming planes of weakness along which a landmass can fail.
For engineering of earth materials, these factors are combined in calculations to determine if a slope meets a minimum safety standard. The generally accepted standard is a factor of safety of 1.5 or greater (where 1.0 is equilibrium, and less than 1.0 is failure). Natural slopes, graded slopes, or graded/natural slope combinations must meet these minimum engineering standards where they impact planned homes, subdivisions, or other types of developments. Slopes adjacent to areas where the risk of economic losses from landslides is small, such as parks and mountain roadways, are often allowed a lesser factor of safety. From an engineering perspective, landslides are generally unstable (may be subject to reactivation), and may be compressible, especially around the margins, which are typically highly disturbed and broken. The scarp area above the landslide mass is also unstable, since it is typically over-steepened, cracked, and subject to additional failures. Although existing landslides are not widespread in the Glendale area, it is probable that many of the steeper hillsides do not meet the minimum factor of safety, and slope stabilization may be needed if development reaches these areas.
Failure of a slope occurs when the force that is pulling the slope downward (gravity) exceeds the strength of the earth materials that compose the slope. They can move slowly, (millimeters per year) or can move quickly and disastrously, as is the case with debris-flows.
Debris-flows can travel down a hillside of speeds up to 200 miles per hour (more commonly, Local Hazard Mitigation Plan Section 9: Landslides
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30 – 50 miles per hour), depending on the slope angle, water content, and type of earth and debris in the flow. These flows are initiated by heavy, usually sustained, periods of rainfall, but sometimes can happen as a result of short bursts of concentrated rainfall in susceptible areas Burned areas charred by wildfires are particularly susceptible to debris flows, given certain soil characteristics and slope conditions.
What is a Debris Flow?
This type of failure is the most dangerous and destructive of all types of slope failure. A debris flow (also called mudflow, mudslide, and debris avalanche) is a rapidly moving slurry of water, mud, rock, vegetation, and debris. Larger debris flows are capable of moving trees, large boulders, and even cars. This type of failure is especially dangerous as it can move at great speeds, is capable of crushing buildings, and can strike with very little warning. As with soil slips, the development of debris flows is strongly tied to exceptional storm periods of prolonged rainfall. Failure occurs during an intense rainfall event, following saturation of the soil by previous rains.
A debris flow most commonly originates as soil slip in the rounded, soil-filled “hollow” at the head of a drainage swale or ravine. The rigid soil mass is deformed into a viscous fluid that moves down the drainage, incorporating into the flow additional soil and vegetation scoured from the channel. Debris flows also occur on canyon walls, often in soil-filled swales that do not have topographic expression. The velocity of the flow depends on the viscosity, slope gradient, height of the slope, roughness and gradient of the channel, and the baffling effects of vegetation. Even relatively small amounts of debris can cause damage from inundation and/or impact (Ellen and Fleming, 1987; Reneau and Dietrich, 1987). Recognition of this hazard led FEMA to modify its National Flood Insurance Program to include inundation by “mudslides.”
Watersheds that have been recently burned typically yield greater amounts of soil and debris than those that have not burned. Erosion rates during the first year after a fire are estimated to be 15 to 35 times greater than normal, and peak discharge rates range from 2 to 35 times higher. These rates drop abruptly in the second year and return to normal after about 5 years (Tan, 1998). In addition, debris flows in burned areas are unusual in that they can occur in Local Hazard Mitigation Plan Section 9: Landslides
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response to small storms and do not require a long period of antecedent rainfall. These kinds of flows are common in small gullies and ravines during the first rains after a burn and can become catastrophic when a severe burn is followed by an intense storm season (Wells, 1987). The United States Geological Survey (USGS), as part of its National Landslide Hazards Program, is developing and updating tools and methodologies to identify and quantify slope stability hazards posed by burned watersheds. Such tools help communities with emergency planning and in dealing with post-fire rehabilitation.7 Historic Southern California Landslides
Historically, there have been many landslides in the Southern California area. Landslides recorded in the 20th century alone caused losses of more than $5 billion (in 2000 dollars).
Many of these landslides have occurred after particularly wet winters, others in response to strong ground shaking during an earthquake. Some of the most dramatic of these cases are briefly described below.
1956 Portuguese Bend Landslide, Palos Verdes
Cost: $14.6 million on California Highway 14 in the Palos Verdes Hills. The Portuguese Bend landslide is a reactivated ancient slide that began its modern movement in August 1956, when displacement was noticed at its northeast margin. Movement gradually extended downslope so that the entire eastern edge of the slide mass was moving within 6 weeks. By the summer of 1957, the entire slide mass was sliding towards the sea. 1969 Glendora, Los Angeles County
Cost: $26.9 million (2000 dollars), in Los Angeles County. The winter of 1969 was one of the wettest on record in the southern California area. The rain caused many of the canyons at the base of the San Gabriel Mountains to overflow, causing debris flows that damaged 175 houses in the Glendora area alone.
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1977-1980 Monterey Park and Repetto Hills, Los Angeles County Cost, $14.6 million (2000 dollars); 100 houses damaged due to debris flows. 1978 Bluebird Canyon, Orange County
Cost: $52.7 million (2000 dollars); 60 houses destroyed or damaged. On October 2, 1978, a portion of the Bluebird Canyon slope gave way, in great part due to the unusually heavy rains in March that may have contributed to initiation of the landslide. Although the 1978 slide area was approximately 3.5 acres, it is suspected to be a portion of a larger, ancient landslide. 1979 Big Rock, California, Los Angeles County
Cost: approximately $1.08 billion (2000 dollars; rockslide causing damage to California Highway 1.
1980 Southern California slides
Cost: $1.1 billion in damage (2000 dollars). Heavy winter rainfall in 1979-90 caused damage in six southern California counties. A sequence of five days of continuous rain that started on February 8 dropped more than 7 inches of water by February 14. Slope failures began to develop by February 15 and then very high-intensity rainfall occurred on February 16. As m u c h a s 8 i n c h e s o f r a i n f e l l i n a 6 - h o u r p e r i o d i n m a n y l o c a t i o n s . R e c o r d s a n d p e r s o n a l observations in the field on February 16 and 17 showed that the mountains and slopes literally fell apart on those last two days.
1983 San Clemente, Orange County
Cost: $65 million (2000 dollars), California Highway 1. Litigation associated with this landslide ultimately cost approximately $43.7 million (2000 dollars). 1983 Big Rock Mesa, Malibu, Los Angeles County
Cost: $706 million (2000 dollars) in legal claims; 13 houses condemned and 300 more threatened due to rockslide triggered by intense rainfall.
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1978-1979, 1980 San Diego County
Experienced major damage from storms in 1978, 1979, and 1979-80, as did neighboring areas of Los Angeles and Orange County, California. One hundred and twenty landslides were reported to have occurred in San Diego County during these 2 years. Rainfall for the rainy seasons of 78-79 and 79-80 was 14.82 and 15.61 inches (37.6 and 39.6 cm) respectively, compared to a 125-year average (1850-1975) of 9.71 inches (24.7 cm). Significant landslides occurred in the Friars Formation, a unit known to be slide-prone. [Of the nine landslides that caused damage in the northern part of San Diego County in excess of $1 million occurred in the Friars Formation, and two in the Santiago Formation. 1994 Northridge Earthquake Landslides
As a result of the magnitude 6.7 Northridge earthquake, more than 11,000 landslides occurred over an area of 10,000 km
2. Most were in the Santa Susana Mountains and in
mountains north of the Santa Clara River Valley. The landslides destroyed dozens of homes, blocked roads, and damaged oil-field infrastructure.
March 1995 Los Angeles and Ventura Counties
Above normal rainfall triggered damaging debris flows, deep-seated landslides, and flooding.
Several deep-seated landslides were triggered by the storms, the most notable being the La Conchita landslide, which in combination with a local debris flow, destroyed or badly damaged 11 to 12 homes in the small town of La Conchita, about 20 km west of Ventura.
There also was widespread debris-flow and flood damage to homes, commercial buildings, and roads and highways in areas along the Malibu coast that had been devastated by wildfire two years before.
2005 Landslide in La Conchita, Ventura County
On January 10, 2005 a landslide struck the sea-side community of La Conchita destroying 36 homes and killing 10 people. The landslide occurred in an area known for prior landslide activity (more recently in 1995) and was the direct result of intense rainfall in the area, compounded by weak sediments and steep slopes.
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2005 Blue Bird Canyon Landslide, Laguna Beach, Orange County On June 1, 2005, a landslide began moving in the area, almost certainly in response to the extremely wet winter rains earlier that year, in January and February. This landslide occurred in the same general area as the 1978 landslides. More than 2 dozen homes were damaged.
2018 Montecito Mudslide, Santa Barbara County
On January 9, 2018, heavy rain following the Thomas Fire triggered massive debris flows, killing 21 persons (with two more missing and presumed dead) and inundating the US Highway 101 causing for a shutdown for a total of 14 days. 214 residential buildings were majorly damaged or destroyed while 194 suffered minor damage. Residential property damage is expected to reach $177 million to $204 million to fully repair and/or rebuild. Estimates show that the closure of the US-101 cost local workers ca. $25-30 million in lost wages.8 Conditions Conducive to Slope Failures
Locations at risk from landslides or debris flows include the following:
x On or close to steep hills;
x Steep road-cuts or excavations;
x Existing landslides or places of known historic landslides (such sites often have tilted power lines, trees tilted in various directions, cracks in the ground, and irregular- surfaced ground);
x Steep areas where surface runoff is channeled, such as below culverts, V-shaped valleys, canyon bottoms, and steep stream channels;
x Fan-shaped areas of sediment and boulder accumulation at the outlets of canyons; and
x Canyon areas below hillside and mountains that have recently (within 1-6 years) been subjected to a wildland fire.
The conditions leading to failure can be varied. The most common of these are described in detail below.
Natural Conditions
Natural processes can cause landslides or re-activate historical landslide sites. The removal
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or undercutting of shoreline-supporting material along bodies of water by currents and waves produces countless small slides each year. Seismic tremors can trigger landslides on slopes historically known to have landslide movement. Earthquakes can also cause additional failure (lateral spreading) that can occur on gentle slopes above steep streams and riverbanks.
Weathering and the decomposition of geologic materials produces conditions conducive to landslides, while human activity often further exacerbates many landslide problems. Many landslides are difficult to mitigate, particularly in areas of large historic movement with weak underlying geologic materials.
Rock falls occur when blocks of material come loose on steep slopes. Weathering, erosion, or excavations, such as those along highways, can cause falls where the road has been cut through bedrock. They are fast moving with the materials free falling or bouncing down the slope. In falls, material is detached from a steep slope or cliff. The volume of material involved is generally small, but large boulders or blocks of rock can cause significant damage.
As the list of historical landslides suggests, landslides are often triggered by periods of heavy rainfall. Earthquakes, subterranean water flow and excavations may also trigger landslides.
Certain geologic formations are more susceptible to landslides than others. Human activities, including locating development near steep slopes, can increase susceptibility to landslide events. Landslides on steep slopes are more dangerous because movements can be rapid.
Wildland fires in hills covered with chaparral are often a precursor to debris flows in burned out canyons. The extreme heat of a wildfire can create a soil condition in which the earth becomes impervious to water by creating a waxy-like layer just below the ground surface.
Since the water cannot be absorbed into the soil, it rapidly accumulates on slopes, often gathering loose particles of soil in to a sheet of mud and debris. Debris flows can often originate miles away from unsuspecting persons, and approach them at a high rate of speed with little warning.
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Impacts of Development
As communities continue to modify the terrain and influence natural processes, it is important to be aware of the physical properties of the underlying soils as they, along with climate, create landslide hazards. Even with proper planning, landslides will continue to threaten the safety of people, property, and infrastructure, but without proper planning, landslide hazards will be even more common and more destructive. The increasing scarcity of build-able land, particularly in urban areas, increases the tendency to build on geologically marginal land. Additionally, hillside housing developments in southern California are prized for the view lots that they provide. Thus, although landslides are a natural occurrence, human impacts can substantially affect the potential for landslide failures to occur. Proper planning and geotechnical engineering can be exercised to reduce the threat of safety of people, property, and infrastructure.
Grading for road construction and development can increase slope steepness. Grading and construction can decrease the stability of a hill slope by adding weight to the top of the slope, removing support at the base of the slope, and increasing water content. Other human activities effecting landslides include excavation, drainage and groundwater alterations, and changes in vegetation.
Excavation and Grading
Slope excavation is common in the development of home sites or roads on sloping terrain.
Grading these slopes often results slopes steeper than the pre-existing natural slopes. Since slope steepness is a major factor in landslides, these steeper slopes can be at an increased risk for landslides. The added weight of fill placed on slopes can also result in an increased landslide hazard. Small landslides can be fairly common along roads, in either the road cut or the road fill sections. Landslides occurring below new construction sites are indicators of the potential impacts stemming from excavation.
Alterations to Drainage and Groundwater Systems
Water flowing through or above ground is often the trigger of landslides. Any activity that increases the amount of water flowing into landslide-prone slopes can increase landslide Local Hazard Mitigation Plan Section 9: Landslides
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hazards. Broken or leaking water or sewer lines can be especially problematic, as can water retention facilities that direct water onto slopes. However, even lawn irrigation in landslide- prone locations can result in damaging landslides. Ineffective storm water management and excess runoff can also cause erosion and increase the risk of landslide hazards. Drainage can be affected naturally by the geology and topography of an area. Development that results in an increase in impervious surface impairs the ability of the land to absorb water and may redirect water to other areas. Channels, streams, ponding, and erosion on slopes all indicate potential slope problems.
Road and driveway drains, gutters, downspouts, and other constructed drainage facilities can concentrate and accelerate runoff flow. Ground saturation and concentrated velocity flow are major causes of slope problems and may trigger landslides.
Changes in Vegetation
Removing vegetation from very steep slopes can increase landslide hazards. Areas that experience wildfire and land clearing for development may have long periods of increased landslide hazard. Also, certain types of non-native ground covers require extensive irrigation to remain green. As a result, clearing and replacement of native ground covers with non- native covers can lead to an increase in slope failures.
Landslide Hazard Assessment
Hazard Identification
Identifying hazardous locations is an essential step towards implementing more informed mitigation activities. Evidence of past slope failures are found throughout the mountain and foothill regions of the City of Glendale. The crystalline rock of the San Gabriel Mountains, weakened by fracturing, shearing, and crushing along numerous fault zones, particularly near the range front, combined with the moderate to extremely steep slopes that have resulted from rapid uplift of the mountains, are important elements that create the setting for the development of slope failures. Similar conditions are present in the Verdugo Mountains and the San Rafael Hills, where rocks are highly weathered and slope gradients of 30 degrees or steeper are common.
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Significantly, however, areas of gross instability such as large deep-seated landslides have not been mapped in the Glendale area, primarily because the highly fractured crystalline rocks that underlie the San Gabriel and Verdugo Mountains and the San Rafael Hills rarely fail as large cohesive units. Three small landslides (Qls) of probable Holocene age have been mapped on the slopes of the Verdugo Mountains and the San Rafael Hills. Because the bedrock in these areas is highly fractured and weathered, the slides consist of small blocks and rock fragments rather than large cohesive masses. These landslides are shown on Plates H-2 and H-11. Numerous other smaller landslides have also occurred in the area, but their size is too small to show on the maps that accompany this report. Large prehistoric landslides have been mapped in the San Gabriel Mountains just to the east of the city, but not in the Glendale area. The distribution of existing landslides in the Glendale area and vicinity was compiled from various publications, including Morton and Streitz, (1969), Crook et al. (1987), and Dibblee, (1989a, 1989b, 1991a, 1991b, 2002).
Areas of surficial instability are common along the steep slopes and canyons of the San Gabriel Mountains, Verdugo Mountains and San Rafael Hills. Unfortunately, detailed maps showing previous sites of surficial slope failures, such as small landslides, slumps, soil slips, and rockfalls have not been compiled or published for the Glendale area. However, an unpublished engineering geology report records several talus rockfalls on steep slopes and roadcuts in the Verdugo Mountains (R. T. Frankian & Associates, 1968). The common occurrence of rockfalls can also be inferred by the abundant talus at the base of steep slopes and in canyons of the San Gabriel Mountains.
The Southern California Area Mapping Project (SCAMP), a cooperative effort between the US Geological Survey (USGS) and the California Geological Survey (CGS), has produced a series of Debris-Flow Occurrence Maps, at a scale of 1:100,000, that predict areas that will be prone to debris flows in normally vegetated hillsides (SCAMP, 2001). The maps are based on their s t u d i e s o f r e c e n t E l N iño events, specifically relating the relationships between rainfall thresholds, terrain, and past debris flow events. Their studies indicate that in upland areas underlain by sedimentary rock and fractured crystalline rock (such as that found in the mountains of Glendale), essentially all past debris flows have occurred on slopes with Local Hazard Mitigation Plan Section 9: Landslides
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gradients of 26 degrees or steeper. The mapped debris flow susceptibility areas in the San Gabriel Mountains include most slopes steeper than 26 degrees, but do not include the heads of the large alluvial fans at the base of the mountains because the flood control dams and debris basins that have been built in these areas are thought to be adequate to contain flows from unburned areas.
However, flows can overwhelm flood control structures during periods of extreme rainfall on a recently burned hillside. For instance, during winters of exceptional rainfall (such as 1934, 1969, 1978, and 1980), debris flows caused widespread property damage and loss of life in communities in and near the base of the San Gabriel Mountains, with areas below burned watersheds receiving the bulk of the damage. For example, in November 1933, there was a large fire in the Montrose-La Crescenta area that burned more than 5,000 acres. Then, on January 1, 1934, intense rainfall fell on the same area that had burned. La Crescenta and Glendale received the brunt of the damage. Several people died, swept away by debris-laden flows that overtopped the canyons in the area. Streets were clogged with debris, and several bridges were washed out (see Plate H-9). In 1978, several canyons within burned watersheds near the Glendale area overtopped their debris basins (Davis, 1980). These canyons include Zachau Canyon located north of Sunland, Shields Canyon north of La Crescenta, and Rubio Canyon north of Altadena. In 1980, the Rubio basin again overflowed, partially inundating one home and threatening several others (Davis, 1980). Therefore, if the right conditions are met, such as high rainfall within burned watersheds, the possibility that debris flows will overtop basins in the Glendale area cannot be precluded.
A detailed study of burned watersheds (including in the San Gabriel Mountains during and after the 1997-1998 winter rains) indicate that less than half of the drainage basins produced debris flows, although the debris flows that did occur were most frequently in response to the initial heavy rainfall. In addition to rainfall and slope steepness, the study highlights the many other factors that contribute to the formation of post-fire debris flows, including the underlying rock type, the shape of the drainage basin, and the presence or absence of water- repellent soils. The goal of these studies is a better understanding of the processes and conditions that generate this hazard, an understanding that is needed in order for Local Hazard Mitigation Plan Section 9: Landslides
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communities to make appropriate decisions on public safety and slope mitigation (Cannon, 2001).
Vulnerability and Risk
Vulnerability assessment for landslides will assist in predicting how different types of property and population groups will be affected by a hazard. Data that includes specific landslide-prone and debris flow locations in the city can be used to assess the population and total value of property at risk from future landslide occurrences.
The potential for slope failure is dependent on many factors and their interrelationships.
Some of the most important factors include slope height, slope steepness, sheer strength, and orientation of weak layers in the underlying geologic unity, as well as pore water pressures.
Joints and shears, which weaken the rock fabric, allow penetration of water leading to deeper weathering of the rock along with increasing the pore pressures, increasing the plasticity of weak clays, and increasing the weight of the landmass.
For engineering of earth materials, these factors are combined in calculations to determine if a slope meets a minimum safety standard. The generally accepted standard is a factor of safety of 1.5 or greater (where 1.0 is equilibrium, and less than 1.0 is failure).
Although existing landslides are not widespread in the area, it is probable that many of the steeper hillsides do not meet the minimum factor of safety and slope stabilization may be needed if development reaches these areas. Natural slopes, graded slopes, or graded/natural slope combinations must meet minimum engineering standards where they impact planned homes, subdivisions, or other types of developments. Slopes adjacent to areas where the risk of economic losses from landslides is small, such as parks and mountain roadways, are often allowed a lesser factor of safety.
While a quantitative vulnerability assessment (an assessment that describes number of lives or amount of property exposed to the hazard of landslides) has not yet been conducted for the City of Glendale, there are many qualitative factors that point to potential vulnerability.
Landslides can impact major transportation arteries, blocking residents from essential Local Hazard Mitigation Plan Section 9: Landslides
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services and businesses. Past landslide events have caused major property damage and significantly impacted city residents. Continuing to map city landslide and debris flow areas will help in preventing future loss.
Factors included in assessing landslide risk include population and property distribution in the hazard area, the frequency of landslide or debris flow occurrences, slope steepness, soil characteristics, and precipitation intensity. This type of analysis could generate estimates of the damages to the city due to a specific landslide or debris flow event. At the time of publication of this plan, data were insufficient to conduct a risk analysis and the software needed to conduct this type of analysis was not available.
Community Landslide Issues
What is Susceptible to Landslides?
The City’s mountain and foothill areas are vulnerable to the types of slope instability mentioned above. Steep-sided slopes along Verdugo Wash and other incised drainages may also be locally susceptible to slope instability. Table 9-1 below is a general summary of the geologic conditions in various parts of the city that provide the environment for slope instability to occur. These conditions usually include such factors as terrain steepness, rock or soil type, condition of the rock (such as degree of fracturing and weathering), internal structures within the rock (such as bedding, foliation, faults) and the prior occurrence of slope failures. Catalysts that ultimately allow slope failures to occur in vulnerable terrain are most often water (heavy and prolonged rainfall), erosion and undercutting by streams, man-made alterations to the slope, or seismic shaking. The summary in Table 9-1 was derived from the Geologic Map (Plate H-2), and other resources. The information in Table 9-1 was then used to prepare the Slope Instability Map for Glendale (Plate H-11).
Landslides can affect utility services, transportation systems, and critical lifelines.
Communities may suffer immediate damages and loss of service. Disruption of infrastructure, roads, and critical facilities may also have a long-term effect on the economy.
Utilities, including potable water, wastewater, telecommunications, natural gas, and electric power are all essential to service community needs. Loss of electricity has the most Local Hazard Mitigation Plan Section 9: Landslides
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widespread impact on other utilities and on the whole community. Natural gas pipes may also be at risk of breakage from landslide movements as small as an inch or two. Some of these issues are discussed in more detail below.
Roads and Bridges
It is not cost-effective to mitigate all slides because of limited funds and the fact that some historical slides are likely to become active again even with mitigation measures. The City alleviates problem areas by grading slides, and by installing new drainage systems on the slopes to divert water from the landslides.
This type of response activity is often the most cost-effective in the short-term but is only temporary. Unfortunately, many property owners are unaware of slides and the dangers associated with them.
Table 9-1: General Slope Instability Potential within the City of Glendale
Area Geologic Conditions Types of Potential
Slope Instability
San Gabriel
Mountains
Steep to extremely steep rock
slopes, most in excess of 40
degrees;
Highly fractured, sheared, faulted,
and crushed crystalline bedrock;
Soils and loose debris in
tributary drainages;
Stream terrace deposits along
major drainage channels;
No known landslides in
Glendale.
Most Probable:
Rockfalls, soil slips on steep
slopes, soil slumps on the edges of
active stream channels, small to
large debris flows.
Less Probable:
Large, deep-seated landslides.
San Rafael
Hills (north of
Highway 134)
Moderate to very steep rock
slopes, most in excess of 26
degrees, many in excess of 40
degrees;
Highly fractured and
weathered crystalline rock;
Soils and loose debris in
tributary drainages and swales;
Several small existing
landslides.
Most Probable:
Soil slips and slumps on moderate to
steep slopes and in drainage swales,
small debris flows, small slides or
rockfalls, surficial soil failures on
steep man-made slopes.
Less Probable:
Large, deep-seated landslides.
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Verdugo
Mountains
Moderately steep to extremely
steep rock slopes, most
between 26 and 40 degrees,
with some slopes steeper than
40 degrees;
Highly fractured, sheared, faulted,
and crushed crystalline bedrock;
Soils and loose debris in
tributary drainages;
A few remnant stream terrace
deposits along major drainage
channels;
Several small existing
landslides;
Rockfalls common according to
R.T. Frankian & Associates
(1968).
Most Probable:
Soil slips and slumps on moderate to
steep slopes and in drainage swales,
small debris flows, small slides or
rockfalls, surficial soil failures on
steep man-made slopes.
Less Probable:
Large, deep-seated landslides.
Major Drainage
Channels –
Verdugo Wash
Gentle to moderate sloping
channel walls with steeper
channel banks (26-40 degrees)
in a few isolated areas;
Poorly bedded Holocene
alluvium consisting of silt, sand
and gravel, with coarse sand,
gravel and boulders near the
mountain front;
No mapped landslides.
Slope instability generally not an
issue.
Valley Plain Very gentle slopes, typically
about 10 degrees or less;
Poorly bedded Holocene and
Pleistocene alluvium consisting
of silt, sand and gravel;
No mapped landslides.
Slope instability generally not an
issue.
Lifelines and Critical Facilities
Lifelines and critical facilities should remain accessible, if possible, during a natural hazard event. The impact of closed transportation arteries may be increased if the closed road or bridge is critical for hospitals and other emergency facilities. Therefore, inspection and repair of critical transportation facilities and routes is essential and should receive high priority. Losses of power and phone service are also potential consequences of landslide events. Due to heavy rains, soil erosion in hillside areas can be accelerated, resulting in loss Local Hazard Mitigation Plan Section 9: Landslides
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of soil support beneath high voltage transmission towers in hillsides and remote areas. Flood events can also cause landslides, which can have serious impacts on gas lines that are located in vulnerable soils.
Landslide Mitigation Activities
Landslide mitigation activities include current mitigation programs and activities that are being implemented by local or city organizations. All proposed development projects require a site-specific geotechnical evaluation of any slopes that may impact the future use of the property. This includes existing slopes that are to remain, and any proposed graded slopes.
The investigation typically includes borings to collect geologic data and soil samples, laboratory testing to determine soil strength parameters, and engineering calculations.
Numerous soil-engineering methods are available for stabilizing slopes that pose a threat to development. These methods include designed buttresses (replacing the weak portion of the slope with engineered fill); reducing the height of the slope; designing the slope at a flatter gradient; and adding reinforcements such as soil cement or layers of geogrid (a tough polymeric net-like material that is placed between the horizontal layers of fill). Most slope stabilization methods include a subdrain system to remove excessive ground water from the slope area. If it is not feasible to mitigate the slope stability hazard, building setbacks are typically imposed.
For debris flows, assessment of this hazard for individual sites should focus on structures located or planned in vulnerable positions. This generally includes canyon areas; at the toes of steep, natural slopes; and at the mouth of small to large drainage channels. Mitigation of soil slips, earthflows, and debris flows is usually directed at containment (debris basins), or diversion (impact walls, deflection walls, diversion channels, and debris fences). A system of baffles may be added upstream to slow the velocity of a potential debris flow. Other methods include removal of the source material, placing subdrains in the source area to prevent pore water pressure buildup, or avoidance by restricting building to areas outside of the potential debris flow path.
There are numerous methods for mitigating rock falls. Choosing the best method depends on the geological conditions (i.e., slope height, steepness, fracture spacing, bedding Local Hazard Mitigation Plan Section 9: Landslides
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orientation), safety, type and cost of construction repair, and aesthetics. A commonly used method is to regrade the slope. This ranges from locally trimming hazardous overhangs, to completely reconfiguring the slope to a more stable condition, possibly with the addition of benches to catch small rocks. Another group of methods focuses on holding the fractured rock in place by draping the slope with wire mesh, or by installing tensioned rock bolts, tie- back walls, or even retaining walls. Shotcrete is often used on the slope face to prevent raveling in highly fractured rock, but its primary purpose is to offer surface protection only.
A third type of mitigation includes catchment devices at the toe of the slope, such as ditches, walls, or combinations of both. Designing the width of the catchment structure requires analysis of how the rock will fall. For instance, the slope gradient and roughness of the slope determines if rocks will fall, bounce, or roll to the bottom. Rock slope stabilization may also include the addition of drains in order to reduce water pressure within the slope (Wyllie and Norrish, 1996).
There are a number of options for management of potential slope instability in developed hillsides.
x Complete a detailed survey and assessment of existing developments in areas recognized to be vulnerable to potential slope failures (for instance, the Verdugo Mountains, the San Rafael Hills, and at the base of the San Gabriel Mountains); x Protect existing development and population where appropriate by physical controls such as drainage, slope-geometry modification, protective barriers, and retaining structures;
x Implement monitoring or warning systems. For instance, in the San Francisco Bay area, the USGS, in cooperation with the National Weather Service, operated a system for real-time warnings for storm-related slope failures (Keefer et al., 1987). Using a combination of tracking storm systems, measuring actual rainfall with a network of rain gauges, and comparing thresholds for the initiation of debris flows, they were able to issue Flash Flood/Debris Watches during the most intense storms (Wilson, 1997). This would be especially valuable for developments adjacent to burned watersheds;
x Post warning signs in areas of potential slope instability; x Encourage homeowners to use landscaping methods that help stabilize the hillsides; x Incorporate recommendations for potential slope instability into geologic and soil engineering reports for additions and new grading; and
x Educate the public about slope stability, including the importance of maintaining drainage devices. USGS Fact Sheet FS-071-00 (May, 2000) and the CGS Note 33 (November, 2001) provide public information on landslide and mudslide hazards.
These are available on the internet (see Appendices A and B).
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Landslide Mitigation Action Items
The landslide mitigation action items below were adopted during the last update of the Local Hazard Mitigation plane. They provided direction on specific activities that the City, organizations, and residents of Glendale could undertake to reduce risk and prevent loss from landslide events. Each action item is followed by ideas for implementation, which were used by the steering committee and local decision makers in pursuing strategies for implementation. Following each action item is a summary of the current status.
Short Term - Landslide #1: Improve knowledge of landslide hazard areas and understanding of vulnerability and risk to life and property in hazard-prone areas.
Ideas for Implementation:
x Conduct a landslide hazard mapping study in the city of Glendale. x Develop public information to emphasize economic risk when building on potential or historical landslide areas.
Coordinating Organization: Hazard Mitigation Plan Steering Group, City of Glendale Departments of Public Works and Management Services
Timeline: 1 - 2 Y e a r s
Plan Goals Addressed: Protect Life and Property
Constraints: Pending Funding and Available Personnel Short Term - Landslide #2: Encourage construction and subdivision design that can be applied to steep slopes to reduce the potential adverse impacts from development.
Ideas for Implementation:
x Increase communication and coordination between the City’s Departments.
Coordinating Organization: Hazard Mitigation Plan Steering Group, City of Glendale Departments of Public Works and Community
Development
Timeline: 1 – 2 Years
Plan Goals Addressed: Increase awareness of mitigation issues through the coordination of all City resources and departments.
Constraints: Pending Funding and Available Personnel Short Term - Landslide #3: Identify safe evacuation routes in high-risk debris flow and landslide areas.
Ideas for Implementation:
x Identify potential debris removal resources.
x Increase participation in regional committee planning for emergency transportation routes.
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x Identify and publicize information regarding emergency transportation routes.
Coordinating Organization: Public Works and Engineering Departments Timeline: 1 – 3 Years
Plan Goals Addressed: Protection of Life and more efficient response of emergency personnel.
Constraints: Pending Funding and Available Personnel Long Term - Landslide #l: Review local ordinances regarding building and development in landslide prone areas.
Ideas for Implementation:
x Create committee of local stakeholders to study issue and make recommendations to staff.
Coordinating Organization: City of Glendale Departments of Community Development, Public works, and City Attorney
Timeline: 3 – 5 Years
Plan Goals Addressed: Protect Life and Property
Constraints: Pending Funding and Available Personnel Long Term - Landslide #2: Limit activities in identified potential and historical landslide areas through regulation and public outreach.
Ideas for Implementation:
x Analyze existing regulations regarding development in landslide prone areas. x Identify existing mechanisms for public outreach / develop new methods of outreach.
Coordinating Organization: Hazard Mitigation Plan Steering Group, City of Glendale Departments of Management Services, Public Works and
Community Development
Timeline: 3 – 5 Years
Plan Goals Addressed: Protect Life and Property
Constraints: Pending Funding and Available Personnel Landslide Resource Directory
County Resources:
Los Angeles County Department of Public Works
900 S. Freemont Avenue
Alhambra, CA 91803
Ph: 626-458-5100
State Resources:
California Department of Conservation: Southern California Regional Office 655 S. Hope Street, #700
Local Hazard Mitigation Plan Section 9: Landslides
City of Glendale, California
2018 9-24
Los Angeles, CA 90017-2321
Ph: 213-239-0878
Fax: 213-239-0984
California Geological Survey
801 K Street
Sacramento, CA 95814
Ph: 916-445-1825
Fax: 916-445-5718
California Division of Forestry
1416 9
th Street
PO Box 944246
Sacramento, CA 94244-2460
Ph: 916-653-5123
California Department of Water Resources
1416 9
th Street
Sacramento, CA 95814
Ph: 916-653-6192
Governor’s Office of Emergency Services (OES)
P.O. Box 419047
Rancho Cordova, CA 95741-9047
Ph: 916-845-8911
Fax: 916-845-8910
California Department of Transportation (Cal Trans)
120 S. Spring Street
Los Angeles, CA 90012
Ph: 213-897-3656
Federal Resources and Programs:
Federal Emergency Management Agency (FEMA) – Region IX
1111 Broadway, Suite 1200
Oakland, CA 94607
Ph: 510-627-7100
Fax: 510-627-7112
Natural Resource Conservation Service (NRCS)
PO Box 2890
Washington, DC 20013
Ph: 202-690-2621
US Geological Survey, National Landslide Information Center 345 Middlefield Road
Local Hazard Mitigation Plan Section 9: Landslides
City of Glendale, California
2018 9-25
Menlo Park, CA 94025
Ph: 650-853-8300
Publications:
Olshansky, Robert B., Planning for Hillside Development (1996) American Planning Association.
This document describes the history, purpose, and functions of hillside development and regulation and the role of planning, and provides excerpts from hillside plans, ordinances, and guidelines from communities throughout the US.
Olshansky, Robert B. & Rogers, J. David, Unstable Ground: Landslide Policy in the United States (1987) Ecology Law Quarterly.
This is about the history and policy of landslide mitigation in the US.
Public Assistance Debris Management Guide (July 2000) Federal Emergency Management Agency.
The Debris Management Guide was developed to assist local officials in planning, mobilizing, organizing, and controlling large-scale debris clearance, removal, and disposal operations.
Debris management is generally associated with post-disaster recovery. While it should be compliant with local and city emergency operations plans, developing strategies to ensure strong debris management is a way to integrate debris management within mitigation activities. The Guide is available in hard copy or on the FEMA website.
USGS Landslide Program Brochure. National Landslide Information Center (NLIC), United States Geologic Survey.
The brochure provides good, general information in simple terminology on the importance of landslide studies and a list of databases, outreach, and exhibits maintained by the NLLC.
The brochure also includes information on the types and causes of landslides, rock falls, and earth flows.
Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-1
SECTION 10: MAN-MADE HAZARDS
Table of Contents
Why Are Man-Made Hazards A Threat to The City of Glendale? 10-2 V u l n e r a b i l i t y a n d R i s k 1 0 - 4 Hazardous Materials Incident Response 10-5
M a j o r A c c i d e n t R e s p o n s e 1 0 - 9 Man-Made Hazard Mitigation Action Items 10-13
R e s o u r c e s 1 0 - 1 6
Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
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Why Are Man-Made Hazards A Threat to The City of Glendale? Man-made hazards differ from natural hazards as they result directly from the actions of people. There are two types of identifiable man-made hazards: technological hazards and terrorism. Technological hazards, such as hazardous material spills, may result from the improper handling or transportation of toxic chemicals, infectious substances, or radioactive materials. Terrorism encompasses intentional, criminal, and malicious acts involving weapons of mass destruction (deployment of biological, chemical, nuclear, and radiological weapons) and conventional weapons (use of arson, incendiary explosives, armed attacks, intentional hazardous materials release, vehicles and cyber-terrorism). Some man-made hazards such as aviation disasters and explosions may fall under the technological or terrorism heading depending upon the circumstances.
Hazardous Materials
Technological hazards involving hazardous material releases can occur at facilities (fixed site) or along transportation routes (off-site). They can occur because of human carelessness, technological failure, intentional acts (terrorism), or natural acts. Hazardous materials releases, depending on the substance involved and type of release, can directly cause injuries and death and contaminate air, water, and soils. While the probability of a hazardous materials release at either a fixed site or along local transportation corridors is relatively low, the consequences of the release of these materials are very serious.
Table 10-1: Significant Hazardous Materials Sites in Glendale:
Facility Name Facility ID Source
Automation Plating Corp. CAD008342784,
CAR000002089,
TRI, LQG
GCC Corp. CAD059240663 TRI
Glendale Public Service
Department
CAD980735864 CERCLIS
San Fernando Valley (Area 2) CAD980894901 CERCLIS
San Fernando Valley (Area 3) CAD980894984 CERCLIS
Scholl Canyon Landfill CA0000927426 LQG
Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
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Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-4
Off-Site Hazardous Materials Characteristics in Glendale The greatest probability of a major hazardous material incident is from a transportation accident. Glendale has four major highways (Interstate 5; Interstate 210; State Route 2; and State Route 134) that surround it. All four are major transportation corridors in the greater Los Angeles and Southern California area. A large number of the trucks that transport goods throughout the Los Angeles area pass through the area described above. A great number of them are transporting cargo along these transportation corridors that is considered hazardous material. Glendale is also impacted by two high-traffic, heavy rail lines that are used by both passenger and cargo carriers. Notably, this rail corridor is approved for, among other products, crude oil transport, a product responsible for several recent large-scale rail disasters.
Historical Incidents of Hazardous Materials Release
To date, the City of Glendale has been fortunate to escape the impact of a major hazardous materials release. However, there have been a number of minor incidents that are consistent with the characteristics of a community like Glendale. Most hazardous materials incidents have occurred in transportation corridors such as freeways and other major transport arteries. The most significant of these releases have consisted of petroleum products such as gasoline and diesel fuel. Previous hazardous materials incidents do not accurately reflect the vulnerabilities that the City faces.
Vulnerability and Risk
With the volume of traffic that flows along the described transportation routes described above, there is a possibility that a hazardous materials release will occur as the result of an accident. An accident of this type would close the freeway or street for several hours requiring traffic to detour through Glendale streets. In the event of an accident involving a vehicle carrying hazardous materials such as a toxic gas, the populated business and residential areas adjacent to the highway would potentially need to be evacuated.
Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
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Hazardous Materials Incident Response
The Glendale Fire Department (GFD) is responsible for responding to hazardous materials incidents in the City. The Hazardous Materials Response System Operating Procedures is designed to interface with the Incident Command System in regard to organization, direction, and control of hazardous materials incidents.
Incident Receipt
Upon receipt of information relating to the possible use of chemicals or materials which are deemed to be of a hazardous nature, an incident shall be entered into the computer and there upon dispatched as an emergency requiring immediate attention and response.
Upon knowledge of this information, information shall be gathered as best as possible to appropriately dispatch the incident. These questions are outlined as follows:
x What is the type/name of spill/chemical/substance?
x What do you see? Have the informant describe the incident. x Can you identify the spilled material?
x Can you estimate the quantity involved?
x What do you smell? Have the informant describe.
x Are there any injuries or victims affected?
x Are there any placards/signs visible on structure/vehicles? When the information has been gathered, assure the informant that resources are responding. If the informant has not been contaminated, they can meet the responders by the street to provide directions. If the informant or others are in a hazardous situation (e.g. building is on fire or they witness a cloud of vapors), they should evacuate immediately and report to start the decontamination process.
Type Code
In order to guarantee the best possible deployment of resources, the following type codes are to be used, using the type code closest to the type of incident that is to be dispatched:
Type Code Description
CHEMO - Chemical Outside
FUEL - Fuel Spill
GASO - Odor of Natural Gas Outside
ODOR - Miscellaneous Odor Investigation
GASI - Odor of Natural Gas Inside
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GMAIN - Broken Gas Main
HAZMAT - Hazardous Materials Carrier
- Tanker Truck
- Hazardous Materials Business
Conditions as follows:
- Chemical spill in a structure
- Large cloud of colored smoke
- Victim(s) complaining of physical reactions due to exposure to substance
- Radioactive substances/locations/incidents
The following assignments are for the purposes of evaluating the incident and upgrading the incident where necessary, in accordance with the appropriate type code. Any incident may be balanced up to a higher response upon determination by the investigating unit.
Type Code Description
CHEMO - Single Engine Assignment
FUEL - Single Engine Assignment
GASO - Single Engine Assignment
ODOR - Single Engine Assignment
GASI - Full Assignment
GMAIN - Broken Gas Main
HAZMAT
DERAIL
WMD
- 2 Hazmat Units, 2 Engines, 1 Truck, Air Utility, Battalion Chief, Paramedic Unit
-3 Engines, 2 Trucks, 2 Urban Search & Rescues,
1 Hazmat Unit, 2 Ambulances| 2 Battalion Chiefs
3 Engines, 2 Trucks, 1 Urban Search & Rescue
2 Hazmat Units, 1 Air Utility, 1 Ambulance, 1 Battalion Chief Dispatch Operations
When an incident is received by dispatch, depending upon the type code used, either a single engine, full assignment, or a HAZMAT response will be dispatched. On single engine and full assignments, the evaluating company will determine whether or not the incident is to be balanced to a higher HAZMAT response.
When an incident is received as a HAZMAT response, or is upgraded to a HAZMAT response, or the Hazardous Materials unit is requested for purposes of utilizing the equipment from the unit, then the Hazardous Materials Unit 24- HM24 will be utilized. At times, there may be a request for a Hazardous Materials Unit to respond to a minor incident or situation for the purpose of utilization of metering devices, s a m p l i n g e q u i p m e n t , c o m p u t e r d a t a b a s e o r Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-7
research information, and other situations falling under the duties of the Hazardous Materials Technician. This is to be coordinated through the on-duty Hazardous Materials Captain in charge of the response team.
Terrorism & Weapons of Mass Destruction (WMD)
FEMA defines terrorism as follows:
Terrorism is the use of force or violence against persons or property in violation of the criminal laws of the United States for purposes of intimidation, coercion, or ransom.
Terrorists often use threats to:
x Create fear among the public.
x Try to convince citizens that their government is powerless to prevent terrorism. x Get immediate publicity for their causes.
Acts of terrorism may include assassinations, bomb scares or bombings, kidnappings, cyber- attacks and hijackings. Terrorists may also make use of WMDs, which can have the following implications:
x The act of terror may not be easily recognizable
x The onset of certain symptoms may only be realized days or weeks after the attack x There may be multiple events unfolding at once
x First responders are placed at a higher risk of becoming casualties x Contamination of critical facilities and large geographic areas may largely increase x Support facilities may be affected
x Specialized State and local response capabilities may quickly be overwhelmed.
Terrorist Target Characteristics
Throughout California there is a limitless number of targets including government offices, shopping areas, religious facilities, water storage facilities, financial institutions, schools, high-profile landmarks, large public gatherings, and utility infrastructures. Glendale is no different than other cities in the Los Angeles metropolitan area in that it contains a number of potential terrorist targets.
Hazard Analysis
California is home to several economically and politically sensitive assets and serves as a symbol of industrial strength and technological prowess with its high-tech industry, vast military production, popular sports and entertainment venues, world-renowned educational Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-8
institutions, and numerous airports and harbors. Glendale is an integral part of Southern California and therefore, the potential for crime, terrorism, and civil unrest needs to be assessed within this regional context.
The City staff worked together to identify specific high-risk facilities in Glendale that could be targets of terrorist attacks. These facilities, for obvious security reasons, are not identified, but the list of the facilities, and their locations, were issued to the Glendale Police Department. The sites were evaluated according to their economic and civic importance – high-occupancy businesses and City facilities that provide critical services were given a high rating. Although several potential targets were identified in the City, this study suggests that within a regional context, as part of Southern California, Glendale has a relatively low level of risk – other high-profile neighboring communities are at higher risk of being targeted for terrorist or civil unrest acts. Nevertheless, with effective prevention and mitigation strategies in place, Glendale can reduce its risk even further.
Terrorist Incident Response
In the City of Glendale, the Glendale Fire and Police Departments are responsible for responding to terrorist attacks and civil disturbances. The Glendale Police Department maintains the list of assets in the City that are considered potential terrorist and/or civil disturbance targets. The Glendale Police Department has a detailed program specifically designed for crowd control issues that was first implemented in the late 1980s. The tactical response unit, which specializes in civil disorder incidences, is referred to as the Tactical Operation Support Squad (TOSS). This unit has been trained to act as a distinct team, responding to civil unrest and unusual events that require a tactical law enforcement presence, such as during earthquakes, catastrophic fires, and flooding conditions. More recently, the Police Department formed a special weapons unit called Special Response Team (SRT). This group is trained to handle unique situations, including acts of terrorism. The Intelligence Unit of the Police Department has been expanded to deal with issues relating to terrorism and organized crime, and the Police Department employs a Crisis Negotiation Team.
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If an event exceeds the capabilities of the Glendale Police Department, additional resources are available. The Glendale Police Department participates in the Los Angeles County Mutual Aid Response Plan – if necessary, assistance can be obtained from the Los Angeles County Sheriff’s Office. Mutual aid agreements and appropriate partnerships to address terrorism and disaster preparedness have been developed and are in place. At the State level, the National Guard would be deployed to help if the situation exceeds the capabilities of the local jurisdictions. Anticipating the possibility that the police facilities in the City could be a target, the Glendale Police Department has developed contingency plans that include the use of redundant facilities from which, if necessary, they can continue operating without interruption.
Consistent with the division of responsibilities as indicated in the California Terrorism Response Plan, the Glendale Police Department does not have the responsibility or the internal capabilities to assess terrorist threats locally. Furthermore, the number of implicit or explicit terrorist threats that they receive is not sufficient to justify a staff position or a tracking system at the City. Therefore, any threats received at the local level are forwarded to the California Anti-Terrorism Information Center (CATIC) for assessment. CATIC was established in response to the World Trade Center and Pentagon attacks on September 11, 2001 and is under the jurisdiction of the State’s Department of Justice, Office of the Attorney General. CATIC acts as a clearinghouse for threats received statewide.
Major Accident Response
When a major accident or terrorist attack occurs, the first few moments are absolutely critical in terms of reducing loss of life and property. First responders must be sufficiently trained to understand the nature and the gravity of the event to minimize the confusion that inevitably follows catastrophic situations. The first responder must then put into motion relevant mitigation plans to further reduce the potential for loss of lives and property damage, and to communicate with the public.
In the City of Glendale, emergency response is handled in accordance with SEMS, with individual City agencies and personnel taking on their responsibilities as defined by the Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-10
City’s Emergency Operations Plan. This document describes the different levels of emergencies, the local emergency management organization, and the specific responsibilities of each participating agency, government office, and City staff. As required by the State, training and exercises are conducted on a regular basis.
Aviation Disaster
Aviation disasters that occur in heavily populated residential areas can result in considerable loss of life and property. The impact of a disabled aircraft that strikes the ground creates the likely potential for multiple explosions resulting in intense fires. The resulting explosions and fires have the potential to cause injuries, fatalities, and the destruction of property at and adjacent to the impact point.
Aviation Disaster Characteristics
Aviation disasters may occur due to mechanical failure, pilot error, or a deliberate act. The number of dead and injured persons along with the amount of property damage that occur from this type of disaster will be dependent upon the size of the aircraft involved, number of persons on the aircraft, location of the crash (residential, commercial, open field, etc.), and number of persons on the ground in the area of the impact. Damage assessment and disaster relief efforts associated with an air crash incident will require support from local governments, private organizations, and from state and local governmental and regulatory agencies.
Historic Incidents of Aviation Disaster
On January 3, 1991, the radar service of a small airplane (Piper 28) was terminated.
Subsequently, it turned toward terrain and collided with a power line cable, then crashed and burned. The accident killed the pilot. No one on the ground was killed or injured. Another documented airplane crash in Glendale is June 21, 1969, and three people were killed.
The most recent example dates from September 22, 2017, when a single-engine plane with two people on board, conducted an emergency landing on Allen Street after losing power to their engine. The pilot and passenger both sustained minor injuries; no buildings or unaffiliated people were damaged or injured.
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While there were only three documented airplane crashes in Glendale, incidents like the Aug. 31, 1986 collision of an Aeromexico DC-9 with a Piper Archer PA-28 over nearby Cerritos are an example of the damage that can occur when aviation disaster occurs in a residential area.
In the Cerritos disaster, the airplanes crashed into a residential neighborhood, claiming 82 lives in all: 64 people on the jetliner, three people in the Piper, and 15 people on the ground.
Damage to homes and other buildings was nearly $4 million. Seventeen homes were severely damaged or destroyed.
Vulnerability and Risk
The skies above Glendale are filled with commercial and private airplanes. Glendale is on the landing path of commercial airplanes inbound to the Los Angeles International Airport (LAX) and Bob Hope Airport (BUR). The 1991 and 2017 airplane crash in Glendale along with other documented aviation disasters, such as the 1986 Cerritos disaster, illustrate the potential for disaster in this area due to the crash of an airplane.
Aviation Disaster Response
In the event of an aviation disaster within the City of Glendale, the Glendale Police Department will share first responder search and rescue responsibility with the Glendale Fired Department. GPD will also be responsible for perimeter security, access control, traffic/crowd control, evacuations, notifications, and safeguarding evidence. In accordance with NIMS, the police department will request law enforcement mutual aid if needed to accomplish these functions. The department will work with Federal (FAA, NTSB), State, and other local law enforcement agencies in coordinating activities and the investigation of the incident.
Vehicular Disaster
A popular trend in using vehicles as ramming weapons to hurt pedestrians has been emerging worldwide. Attacks of this nature have made public spaces with vehicle access prime targets. Such attacks eliminate the need for expensive, hard-to-find or hard-to-build weapons. Instead, they allow a greater variety of people to misuse cars and trucks to drive Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-12
into crowds and injure or kill dozens of people at once. In order to prevent such attacks from happening in the City of Glendale, public gatherings and spaces, such as the Farmer’s Market o r s t r e e t p r o t e s t , n e e d t o b e p r o t e c t e d a ccordingly through the installment of bollards, vehicle slow-downs, and the temporary use of large city-owned vehicles to block access to others during an event.
Community Man-Made Hazard Issues
The impact upon the community will depend on the type and breadth of man-made hazard.
While specialized resources will respond to the city to assist it make take time for that assistance to arrive. Local public safety resources may be depleted causing delayed responses to emergency and routine community service requests.
Community panic, intense media interest, and a surge of patients at local hospitals and urgent care centers can be expected. Rapid assessment of the size and type of incident, activation of the NIMS emergency management infrastructure, designation of injured field treatment and casualty collection points will be critical. Efforts to assess the situation and provide clear emergency management instructions to the public will be crucial. The following describe some concerns that may be expected from a man-made hazard incident:
Downwind Evacuation
The release of a hazardous substance may cause a plume that travels for miles. Evacuation of local residents as well as notification to neighboring jurisdictions’ emergency agencies will potentially be necessary.
Traffic Restrictions and Congestion
Roads, freeways, and transit systems may be affected due to a man-made hazard incident.
Panic may cause some residents to self-evacuate. As a result of this, traffic congestion and gridlock may occur. These factors will slow the response time for assisting agencies, specialized resources and equipment, and additional emergency services personnel.
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Hospital Surge
Injured victims or persons that believe they’ve been injured or exposed to a toxic substance may leave the area of a manmade hazard incident and transport themselves to care facilities.
The influx of persons seeking treatment will impact the availability of treatment facilities for persons being sent to those facilities by on-site emergency services personnel.
Man-Made Hazard Mitigation Action Items
The Glendale Police Department is part of the Los Angeles Area Terrorist Early Warning Group (TEW) and Los Angeles County Law Enforcement Mutual Aid Area “C”. The Glendale Fire Department is part of the Verdugo Fire System and Los Angeles County Fire Mutual Aid Area “C”. The mutual aid groups and the Verdugo Fire System provide additional personnel and resources to the City of Glendale’s emergency services in times of disaster.
The TEW provides an integrated threat assessment from a multi-jurisdictional perspective.
Local law enforcement and city and county fire departments work with emergency management, FBI, Department of Health Services, as well as other state and response officials to acts of terrorism. The TEW provides a Unified Command Structure, gauges resource needs and shortfalls, continuously monitors situational awareness and status, and acts as the point of contact for interagency liaison in order to develop options for incident resolution courses of action. TEW also provides support for Terrorism and Infrastructure Protection, Public Order (Riots/Disturbances), Civil-Military Interoperability for Urban Operations, Networked Threats and Emerging Threats, and Counterterrorism Technology Test Bed.
The man-made hazards mitigation action items provide direction on specific activities that organizations and residents in the City of Glendale can undertake to reduce risk and prevent loss from such events. Each action item is followed by ideas for implementation, which can be used by the Hazard Mitigation Planning Committee and local decision makers in pursuing strategies for implementation.
Mitigation action items appear in their order of priority at the time of submittal of this plan.
This is not to negate the option to re-prioritize as may be necessitated by environmental, Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
2018 10-14
economic, feasibility or policy influences. Priorities were determined by the City departments responsible for the development of mitigation actions and their implementation. Due consideration was given to the importance of each item and evaluated against the estimated costs. Furthermore, these estimated costs were evaluated against projected city revenue.
Short Term - Manmade #l: Enhance the response capabilities of firefighters through training on event specific (manmade hazards) incidents.
Ideas for Implementation:
Department: Glendale Fire Department
Timeline: 2 y e a r s
Plan Goals Addressed: Provide a broad knowledge base to first responders.
Constraints: Scheduling and availability of courses through the Office of Domestic Preparedness and the National Fire
Academy as well as others. There may be budgetary
constraints for seminars and conferences by other
vendors.
Short Term - Manmade #2: Develop response protocol and matrices for manmade hazard events other than hazardous materials response.
Ideas for Implementation:
Coordinating Organization: Fire Department with input from affected city departments dependent on event type
Timeline: 2 + y e a r s
Plan Goals Addressed: Appropriate and safe response to manmade hazard events.
Constraints: Dependent on the results of item #1 and the cooperation of other city departments.
Short Term - Manmade #3: Building access accountability/hardening of City Facilities Ideas for Implementation:
x Secure sensitive/critical City infrastructure and facilities such as substations, traffic control centers, water treatment facilities, and other vital resources x Ensure that there are policies and procedures in place for City facility access Coordinating Organization: City of Glendale Departments of Management Services, Public Works, Water and Power, Fire, and Police
Timeline: 6 months – 2 years
Local Hazard Mitigation Plan Pandemic Section 10: Man-Made Hazards City of Glendale
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Plan Goal Addressed: Maintain and enhance the ability to provide emergency response services.
Long Term - Manmade #1: Sustained response capability cache.
Ideas for Implementation:
x Maintaining response capabilities throughout an extended disaster response. The fire department will purchase supplies, food stores and equipment that would accommodate the retention of personnel for the duration of a response for up to 200 city employees for a period of ten days.
Coordinating Organization: Glendale Fire Department
Timeline: 1-5 years
Plan Goals Addressed: Preparedness
Constraints: Budgetary conditions mandate that this effort be undertaken over multiple fiscal years.
Long Term - Manmade #2:
Enhance Interoperability and Communications
Ideas for Implementation:
x Determine if current radio equipment used by City of Glendale Fire and Police Departments are adequate for communication with mutual aid partners x Determine additional communication needs to maintain interoperable communications for the next five years.
x Plan recurring interoperability exercises with mutual aid partners
Coordinating Organization: City of Glendale Police and Fire Departments Timeline: O n g o i n g
Plan Goals Addressed: Maintain and enhance the ability to provide emergency response services.
Constraints: Pending funding and available personnel Long Term - Manmade #3: Conduct Local and Regional Training with Emergency Response Services
Ideas for Implementation:
x Establish regular training calendar including exercises with local and regional response services
x Conduct biannual training exercises with partners in the Operational Area
Coordinating Organizations: Glendale Police and Fire Departments Timeline: Ongoing
Plan Goal Addressed: Maintain the ability to provide emergency response services.
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Resources
City of Glendale – Safety Element
Government Information Library
[email protected]
303-492-8834 (ph)
303-492-1881 (fx)
Norlin Library, Third Floor
California Department of Toxic Substances Control: www.dtsc.ca.gov
FEMA – Guide on Terrorism
https://www.fema.gov/media-library-data/20130726-1549-20490-0802/terrorism.pdf
NTSB Identification: WPR17LA212
https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20170923X20448&key=1 Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-1
SECTION 11: PANDEMIC
Table of Contents
I n t r o d u c t i o n 1 1 - 2
E n g i n e e r i n g a n d E n v i r o n m e n t a l C o n t r o l s 1 1 - 3 A d m i n i s t r a t i v e C o n t r o l s 1 1 - 3 P e r s o n a l P r o t e c t i v e E q u i p m e n t 1 1 - 4 Pandemic Influenza Guidelines for Ems Providers 11-4 P a n d e m i c M i t i g a t i o n A c t i o n I t e m s 1 1 - 9 P a n d e m i c I n f l u e n z a P l a n n i n g 1 1 - 1 0 P u b l i c a t i o n s 1 1 - 1 2
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-2
Introduction
The City of Glendale is concerned about the potential of an influenza pandemic. Our primary focus and energy will be directed toward the safety of our employees and the community we serve.
In order to prepare for such an event, the City of Glendale is adopting a city-wide pandemic plan. This plan will mirror the plans for the World Health Organization (WHO) and the L.A.
County Department of Public Health.
The plan clearly defines the roles and responsibilities for:
x General Government
x Fire/EMS
x Police
x HR and Community Development
x Glendale Water & Power (GWP)
x Glendale Unified School District (GUSD)
x Glendale Community College
x USC Verdugo Hills Hospital
x Adventist Health Glendale
x Dignity Health, Glendale Memorial Hospital
x LA County DHS
During an influenza pandemic, it can be expected that transmission of the pandemic virus will occur in heavily populated locations, such as the workplace. Person to person transmission is possible between co-workers, along with between customers and employees in general work settings.
In order to reduce the risk of exposure to employees, employers can use a set of occupational safety and health controls referred to as “hierarchy of controls.” These types of measures are listed below:
x Engineering Controls
x Administrative Controls
x Work Practices
x Personal Protective Equipment (PPE)
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-3
Engineering and Environmental Controls
These methods reduce exposure to the virus by changing the work environment. These controls do not rely on worker or customer behavior. Examples:
x Installing physical barriers, such as counters and customer windows x Installing drive thru windows when appropriate
x Using specialized negative pressure ventilation systems.
Administrative Controls
These controls establish infection control measures that modify a worker’s work schedule and tasks in a way to minimize their exposure to influenza at the workplace. Examples:
x Develop a policy to encourage sick employees to stay home without fear of reprisal x Discontinue nonessential travel to locations with high rates of illness x Develop practices that minimize face-to-face contact between workers, such as e- mail, phone calls, teleconferences, flexible hours to limit the number of employees in one work environment
x Maintain good communication with a forum for answering questions of concerned employees.
Work Practices
These controls are procedures for safe and proper work that are used to reduce the duration, frequency or intensity of exposure to influenza. Examples:
x Provide resources that promote good personal hygiene
o Hand soap
o Hand sanitizer
o Disposable towels
o Tissues
o No-touch trash cans
o Disinfectant cleaner for work surfaces
x Provide resources that explain the importance of
o Washing your hands
o Avoiding touching your face
o Covering your mouth when coughing or sneezing
x Encourage workers to get flu vaccinations
x Provide workers with the most up-to-date information on influenza x Provide accessible education and training in the appropriate language and literacy level
x Develop a policy to minimize contact between works, clients, and customers.
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City of Glendale, California
2018 11-4
Personal Protective Equipment
Personal Protective Equipment (PPE) is essential. Understand that PPE can help prevent exposures. It is imperative that employees use the appropriate PPE and that it properly fits.
PPE should be used in conjunction with the other prevention interventions, such as good hygiene and good healthy practices. Examples of PPE:
x N95 mask
x Gloves
x Goggles/safety glasses.
Just as communities plan and prepare for severe natural disasters (such as earthquakes), they should plan and prepare for a severe influenza pandemic. This guidance will be updated as new information becomes available that better defines the epidemiology of influenza transmission, the effectiveness of control measures, and the social, ethical, economic, and logistical costs of mitigation strategies.
Pandemic Influenza Guidelines for Ems Providers
For EMS providers, the winter season is routinely characterized as a time of high volume and taxing demand. Therefore, even under normal circumstances, the healthcare system in Los Angeles County (LAC) can be easily overwhelmed. This high value demand would be even further increased during a pandemic and will challenge our healthcare resources to levels not previously experienced.
The World Health Organization (WHO) has developed a global influenza preparedness plan which defines the phases of a pandemic and recommends measures to take before and during a pandemic according to phases. LAC has adopted these phases to facilitate pandemic planning, response, and recovery activities.
While preparing and planning for a pandemic will not eliminate the increased demand that comes with a pandemic, preparation and planning can ease the burden on FIRE/EMS personnel and administrators and ensure that access to necessary resources continues.
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
201811-5
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
201811-6
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
201811-7
201
8 11
-
7 Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
201811-8
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-9
Risk Analysis
The Los Angeles County Department of Public Health has projected the impact of an influenza pandemic upon LAC’s medical and healthcare system using the Centers for Disease Control and Prevention’s (CDC) FluSurge 2.0 software. Estimates were calculated according to a modified model of the 1918 pandemic. It assumed:
x A 30% attack rate,
x A duration of an initial wave of illness to extend about 12 weeks, and x Hospitalization (if needed) to last about five days.
With those assumptions, the model predicted the number of hospitalizations in LAC to be about 376,000, and the predicted mortality to be about 63,000 deaths.
Research Needs
It is recognized that additional research is needed to validate the proposed measures, assess their effectiveness, and identify adverse consequences. This research will be conducted as soon as practicable and will be used in providing updated guidance as required.
Pandemic Mitigation Action Items
Due to the low frequency by which pandemics occur, drills and exercises are required to test plans and to maintain response proficiency. Such real-world operational experience can yield invaluable empirical evidence regarding how readily particular pandemic mitigation measures might be implemented, along with how well they might work if applied on a larger scale and/or for longer duration. Drills and exercises permit individuals and organizations to carry out their normal duties and relate to each other under unusual circumstances in simulated environments.
Long Term – Pandemic #1: Participate in repetitive training events for Point of Distribution (POD) of vaccines for pandemic diseases.
Ideas for Implementation:
x Continue planning preparation efforts for implementing pandemic mitigation measures throughout all segments of the community by providing hand-sanitizers and displaying public health education posters throughout all public counters within the city
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-10
x Continue to support the County of Los Angeles Public Health in any exercise that will prepare the community in general.
Long Term – Pandemic #2: Glendale will develop and approve a plan to respond to a surge in patients due to a 10% influenza infection rate.
Coordinating Organization: Glendale Fire Department, City of Glendale Management Services Department
Timeline: O n g o i n g
Plan Goals Addressed: Protect Life and Property, Emergency Services Constraints: Pending Funding and Available Personnel Long Term – Pandemic #3: Ensure that 100% of identified populations are vaccinated against seasonal influenza.
Coordinating Organization: Glendale Fire Department, City of Glendale Management Services Department
Timeline: O n g o i n g
Plan Goals Addressed: Protect Life and Property, Emergency Services Constraints: Pending Funding and Available Personnel
Pandemic Influenza Planning
The Department for Homeland Security published Pandemic Influenza Preparedness, Response and Recovery Guide for Critical Infrastructure and Key Resources in 2006. It can be found at:
https://www.dhs.gov/sites/default/files/publications/cikrpandemicinfluenzaguide.pdf.
The CDC has created a State and Local Pandemic Influenza Planning Checklist, and it is available at https://www.cdc.gov/flu/pandemic-resources/pdf/state-local-checklist.pdf. In addition, recommendations for implementation of pandemic mitigation strategies are available at https://www.cdc.gov/flu/pandemic-resources/index.htm.
Reliable, accurate, and timely information on the status and severity of the pandemic also will be posted on https://www.cdc.gov/flu/pandemic-resources/index.htm and http://publichealth.lacounty.gov/acd/Flu.htm.
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-11
ADDITIONAL RESOURCES: WEBSITES
International
World Health Organization
x Avian and other zoonotic influenza
http://www.who.int/influenza/human_animal_interface/en/ x Global Influenza Preparedness Plan
http://www.who.int/csr/resources/publications/influenza/WHO_CDS_CSR_GIP_20 05_5.pdf
Federal
Centers for Disease Control and Prevention
x Pandemic Influenza
https://www.cdc.gov/flu/pandemic-resources/index.htm
o Pandemic Basics
o National Pandemic Strategy
o Monitoring for Influenza Viruses
o Planning and Preparedness Resources
Department of Health &Human services
x Pandemic Influenza
x https://www.hhs.gov/about/agencies/oga/global-health-security/pandemic- influenza/index.html
o HHS Pandemic Influenza plan
o HHS National Vaccine Plan
Department for Homeland Security
x Pandemic Influenza Continuity of Operations Plan Template https://www.fema.gov/media-library-data/1396880633531-
35405f61d483668155492a7cccd1600b/Pandemic_Influenza_Template.pdf OSHA Guidance on Preparing Workplaces for an Influenza Pandemic https://www.osha.gov/Publications/influenza_pandemic.html California
Department of Public Health Division of Communicable Disease Control x https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/DCDC.aspx Los Angeles
Health Services Emergency Medical Services Agency
http://dhs.lacounty.gov/wps/portal/dhs/ems/
Department of Public Health Acute Communicable Disease Control Program http://publichealth.lacounty.gov/ACD/
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
2018 11-12
Publications
Modeling Community Containment for Pandemic Influenza. A Letter Report. Washington, DC.: The National Academies Press; 2006
Local Hazard Mitigation Plan Section 11:
Pandemic
City of Glendale, California
201811-13
CITY OF GLENDALE
2025 URBAN WATER MANAGEMENT PLAN
APPENDIX I
LOS ANGELES COUNTY ALL-HAZARDS MITIGATION
PLAN
2025 County of Los Angeles
All-Hazards Mitigation Plan
Chief Executive%SœJN -%SœJN of Emergency Management
Page
1 of
204
County of Los Angeles
All-Hazards Mitigation Plan
Acknowledgement
The Los Angeles County Board of Supervisors gratefully acknowledges the following agencies/jurisdictions who contributed to the development of this plan.
County Departments
Aging and Disabilities
UVNSxNJqpVvN%SœJN
UVNS1qmpAV_AIV]Vpy%SœJN
Beaches and Harbors
Economic Opportunity
Health Services
Human Resources
Parks and Recreation
Public Health
Public Social Services
Public Works
Regional Planning
Fire (LACoFD)
Internal Services
Sheriff (LASD)
Disaster Management Area Coordinators
State of California
A]VSal_VAavNl_al¯m%SœJNaS^NlTN_Jy1NlvVJNmA]%1 California State Council on Developmental Disabilities (SCCD) External Partners
Access Services
Alzheimer’s Association
Catholic Charities
City of Beverly Hills
City of Long Beach
Disability Community Resource Center
Eastern Los Angeles Regional Center
Emergency Network Los Angeles
Habitat for Humanity
Harbor Regional Center
Lanterman Regional Center
!am_TN]Nmaq_py%SœJNaSLqJApVa_
Los Angeles County Sanitation Districts
Los Angeles County Metropolitan
Transportation Authority
Los Angeles Regional Food Bank
Neighborhood Legal Services of Los Angeles
County
Puente Hills Habitat Preservation Authority
South Central Los Angeles Regional Center
Westside Regional Center
Cover Photo Credits: !am_TN]Nmaq_pyUVNSxNJqpVvN%SœJNaq_pywVLNa^^q_VJApVa_m lA_JU
Los Angeles County Department of Public Works
County of Los Angeles
All-Hazards Mitigation Plan
Table of Contents
Acknowledgement ................................................................................................................. 1 Letter of Promulgation ........................................................................................................... 2 1 _plaLqJpVa_-qliamNA_L1JaiN ................................................................................ 6
1.1 Purpose ...................................................................................................................... 7
1.2 Scope ......................................................................................................................... 7
1.3 Legal Authority and Requirements ......................................................................... 7
1.4 Plan Organization ..................................................................................................... 8 2 Planning Process ............................................................................................................. 9
2.1 Overview of the Planning Process ........................................................................ 10
2.2 Stakeholder Engagement ...................................................................................... 13
2.3 Public Involvement and Outreach ........................................................................ 18
2.4 Review and Incorporation of Existing Plans and Reports .................................. 19 3 a^^q_Vpy-laœ]N ........................................................................................................ 22
3.1 Los Angeles County Overview .............................................................................. 23
3.2 Geography and Land Use ..................................................................................... 24
3.3 Social Vulnerability ................................................................................................. 25
3.4 Economy and Critical Infrastructure ..................................................................... 28
3.5 Climate and Environmental Conditions ............................................................... 29
3.6 Regional Collaboration and Planning Efforts ...................................................... 30
3.7 Implications for Hazard Mitigation Planning ....................................................... 31 4 Climate Change ............................................................................................................ 32
4.1 Climate Change Overview .................................................................................... 33
4.2 _pNTlApV_T]V^ApNUA_TNV_paA|AlL-laœ]Nm ............................................... 34
4.3 Climate Mitigation Strategies ................................................................................ 36
4.4 Clima
te Change Conclusion ................................................................................. 37 County of Los Angeles
All-Hazards Mitigation Plan
5 Integrating Access and Functional Needs (AFN) into Hazard Mitigation .............. 38
5.1 AFN Introduction .................................................................................................... 39
5.2 Inclusion of AFN and Vulnerable Populations in Planning ................................ 39
5.3 Assessment of AFN Needs .................................................................................... 40
5.4 Coordination with AFN Support Agencies .......................................................... 42
5.5 AFN Conclusion ...................................................................................................... 42 6 A|AlLLN_pVœJApVa_A_L0Vm\mmNmm^N_p ............................................................... 43
6.1 A|AlLLN_pVœJApVa_%vNlvVNw ............................................................................. 44
6.2 :V]LœlN ..................................................................................................................... 49
6.3 Earthquake .............................................................................................................. 57
6.4 Extreme Heat ........................................................................................................... 67
6.5 Drought .................................................................................................................... 74
6.6 Flooding .................................................................................................................. 82
6.7 Dam Failure ............................................................................................................. 92
6.8 Land Movement .................................................................................................... 102
6.9 Tsunami .................................................................................................................. 114
6.10 Severe Wind and Tornado ............................................................................... 120
6.11 Mass Violence .................................................................................................... 130
6.12 Cybersecurity Incidents .................................................................................... 135
6.13 Transportation Incidents ................................................................................... 142
6.14 Public Health Emergencies .............................................................................. 147 7 Mitigation Strategy ...................................................................................................... 152
7.1 Mitigation Strategy Overview .............................................................................. 153
7.2 Mitigation Goals and Objectives ........................................................................ 153
7.3 Existing Mitiga tion Capabilities .......................................................................... 155
7.4 LN_pVœJApVa_A_L_A]ymVmaS"VpVTApVa_1plApNTVNm ......................................... 172 County of Los Angeles
All-Hazards Mitigation Plan
7.5 Status of Previous Mitigation Efforts ................................................................... 184
7.6 Prioritization and Implementation of Mitigation Actions ................................. 186
7.7 Integration with Other Plans ............................................................................... 189
7.8 Mitigation Action Plan .......................................................................................... 191 8 Plan Maintenance ........................................................................................................ 196
8.1 Community Participation in Plan Maintenance ................................................. 197
8.2 "a_VpalV_TvA]qApVa_A_L"AV_pN_A_JN......................................................... 198
8.3 Criteria for Updating the Hazard Mitigation Plan ............................................. 199
8.4 Plan Update ........................................................................................................... 200
8.5 Integration with Other Plans ............................................................................... 201 9 Plan Adoption .............................................................................................................. 202
9.1 Plan Adoption Overview ...................................................................................... 203 Appendices ......................................................................................................................... 204 County of Los Angeles
All-Hazards Mitigation Plan
1 _plaLqJpVa_-qliamN
and Scope
County of Los Angeles
All-Hazards Mitigation Plan
1.1 Purpose
The 2025 All-Hazard Mitigation Plan (AHMP) was developed in collaboration with a wide range of stakeholders representing County Departments and other external mpA\NUa]LNlmSla^JVpVNm ]aJA]qpV]VpVNm _a_-TavNl_^N_pA]alTA_V|ApVa_mA_LmpApN agencies. The purpose of this AHMP is to form the strategic-level foundation for hazard mitigation efforts undertaken by the County of Los Angeles. The 2025 AHMP is an update to the 2020 version of the plan and seeks to maintain the County’s continuing commitment to hA|AlL^VpVTApVa_AmAJlVpVJA]mpNiV_lNLqJV_TUA|AlLlVm\m^A\V_T Ja^^q_VpVNmmASNlA_LIqV]LV_TJaq_pywVLNlNmV]VN_JN
1.2 Scope
A|AlL^VpVTApVa_VmLNœ_NLV_pUNaLNaSNLNlA]0NTq]ApVa_m0 Am¬A_ymqmpAV_NL action taken to reduce or eliminate the long-term risk to human life and property from UA|AlLm3UVm"-VLN_pVœNmA_Lilaœ]NmUA|AlLmA_A]y|NmpU NiNai]NA_LJlV tical V_SlAmplqJpqlNAplVm\A_LilavVLNmAmNlVNmaS^VpVTApVa_mpl ApNTVNmAV^NLAplNLqJV_T hazard risk. The plan also describes actions to integrate vulnerable communities including people with Access and Functional Needs (AFN) into hazard mitigation planning and other efforts. The AHMP is inte nded to function as a strategic plan for UA|AlL^VpVTApVa_A_LwUV]N_apA_N^NlTN_Jyi]A_Ja^i]N^N_pm pUN!am_TN]Nm County Operational Area Emergency Operations Plan. This plan contains mitigation strategies for County-owned facilities or other areas under the jurisdiction of the County of Los Angeles. Hazard mitigation st rategies for incorporated cities within Los Angeles County may be found in that city’s hazard mitigation plan.
1.3 Legal Authority and Requirements
Historically local hazard mitigation planni ng has been driven by federal law. The Disaster Mitigation Act (DMA) of 2000 amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act of 1988 with new requirements for hazard mitigation.
The DMA aSN^iUAmV|NLpUN_NNLSalmpApNplVIA]A_L]aJA]N_pVpV NmpaJ]amN]y coordinate on hazard mitigation efforts and formed the legal basis for the Federal Emergency Management Agency’s (FEMA) current mitigation plan requirements in order to utilize Hazard Mitigation Assistance grant programs. This plan was prepared County of Los Angeles
All-Hazards Mitigation Plan
pursuant to the requirements set forth in the DMA of 2000 and other FEMA hazard mitigation policy guidance.
1.4 Plan Organization
The AHMP is organized into nine (9) mNJpVa_mNxJ]qLV_TpUNiiN_LVJNm including:
1. Introduction: VmJqmmNmpUNiqliamNmJaiNA_L]NTA]AqpUalVpyaSpUNi]A_
2. Planning Process: Describes the planning process that was undertaken by the Hazard Mitigation Planning Committee to create this updated 2025 AHMP .
3. a^^q_Vpy-laœ]N %vNlvVNwmpUNq_VkqNTNaTlAiUVJJ]V^ApVJN_vVla_^N_pA] and socioeconomic factors that make up Los Angeles County and their implications for hazard mitigation planning.
4. Climate Change: Outlines the impacts of climate change in Los Angeles County and potential mitigation and adaptation measures.
5. Integrating AFN into Hazard Mitigation: Discusses strategies for integrating people with Access and Functional Needs (AFN) into prevention and hazard mitigation efforts.
6. A|AlLLN_pVœJApVa_A_L0Vm\mmNmm^N_p LN_pVœNmA_Lilaœ]Nm nine (9) natural and four (4) human-caused hazards that may impact Los Angeles County including: wV]LœlNNAlpUkqA\NNxplN^NUNApLlaqTUpŔaaLV_TLA^SAV]ql N ]A_L^avN^N_ppmq_A^VmNvNlNwV_LA_Lpal_ALa^AmmvVa]N_JNJyINlmNJqlVpy V_JVLN_pmplA_mialpApVa_V_JVLN_pmA_LiqI]VJUNA]pUN^NlTN_JVNm
7. Mitigation Strategy: Delineates the overall strategy for the County’s hazard ^VpVTApVa_NSSalpmV_J]qLV_TTaA]mA_LaI[NJpVvNmNxVmpV_T^VpVTApVa_JAiAIV]VpVNm and an analysis of mitigation actions.
8. Plan Maintenance: Outlines how the plan will be maintained annually ahead of pUN_NxpSq]]i]A_qiLApNV_œvNyNAlm
9. Plan Adoption: Discusses updates to the plan and implementation following plan adoption.
a]]awV_TpUNmNmNJpVa_mpUNlNAlNA_ALLVpVa_A] six (6) appendices with supporting ^ A p N l V A ] m m q J U A m U A | A l L ^ A i m ^ N N p V _ T ^ V _ q p N m S l a ^ i ] A _ _ V _ T ^ NNpV_Tm A_L information about the public engagement efforts during the planning process.
County of Los Angeles
All-Hazards Mitigation Plan
2 Planning Process
County of Los Angeles
All-Hazards Mitigation Plan
2.1 Overview of the Planning Process
The 2025 Los Angeles County All-Hazard Mitigation Plan (AHMP) update builds upon the robust all-hazard planning framew ork established by the 2020 All-Hazards "VpVTApVa_-]A_wUV]NV_JalialApV_T_Nw^NpUaLa]aTVNmmpA\NUa ]LNlN_TATN^N_p and compliance requirements. The planning process for this update emphasized V_J]qmVvVpy plA_miAlN_Jy A_L pUN V_pNTlApVa_ aS N^NlTV_T J]V^ApN ALAipApVa_ considerations.
3UVmi]A__V_TilaJNmmSa]]awNLAmplqJpqlNLiUAmNLAiilaAJUA] VT_NLwVpU"¯m !aJA]"VpVTApVa_-]A__V_T-a]VJyqVLN 0lNkqVlN^N _pmA_LTqVLA_JN Sla^pUNA]VSal_VAavNl_al¯m%SœJNaS^NlTN_Jy1NlvVJNmA]%1 3UVmAiilaAJU began witUila[NJpV_VpVApVa_wUNlNpUNmJaiNpV^N]V_NA_LmpA\NUa]LNlmwNlNLNœ_NL Stakeholder and public engagement were prioritized to ensure representation from LVvNlmNTlaqimV_J]qLV_TUVmpalVJA]]yq_LNllNilNmN_pNLJa^^q_V pVNmA_LJ]V^ApN - vulnerable populations.
Data Ja]]NJpVa_A_LA_A]ymVm]NvNlATNLqiLApNLUA|AlLJ]V^ApNA_Lvq]_NlAIV]VpyLApA Sla^]aJA]mpApNA_LSNLNlA]maqlJNmilavVLV_TASaq_LApVa_ SalN_UA_JNLlVm\A_L vq]_NlAIV]VpyAmmNmm^N_pmA|AlLilaœ]NmwNlNqiLApNLpaV_J]qLNJ]V^ApNila[NJpVa_m and cascading impact scenarios. Mitigation strategies were revised and prioritized with a renewed focus on climate resilience and nature-based solutions. Strategies were also developed incorporating people with acce ss and functional needs throughout each comia_N_paSpUN"-V_A]]y^NpUaLmSal^a_VpalV_TA_LNvA]qApVa_aS^VpVTApVa_ NSSalpmwNlNLNœ_NLV_pUNi]A_^AV_pN_A_JNA_LV^i]N^N_pApVa_ mplApNTy3AI]N-1 provides a timeline of the major plan upda te tasks and milestones over the planning process.
Table 2-1 AMHP Planning Timeline
Date 3Am\m People Involved
February
2025
0NvVNwNLpUN"-A_LVLN_pVœNL
components that require update.
OEM AHMP Project
Team
Collected and reviewed existing
LaJq^N_pmV_J]qLV_TpUN3UlNApA_L
A|AlLLN_pVœJApVa_A_L0Vm\
Assessment (THIRA) along with resources
for people with access and functional
OEM AHMP Project
Team
County of Los Angeles
All-Hazards Mitigation Plan
Date 3Am\m People Involved
needs and people experiencing
homelessness.
February
2025
Met with state Hazard Mitigation
Planning Team.
OEM AHMP Project
3NA^A]%1
Mitigation Division
LN_pVœNLpUNV_VpVA]]VmpaSmpA\NUa]LNlm
and ensured organizations that work with
and represent people with access and
functional needs were engaged in the
planning process. External stakeholders
V_J]qLN_NVTUIalV_TJa^^q_VpVNm]aJA]
A_LlNTVa_A]ATN_JVNmA_LapUNlm
OEM AHMP Project
Team
Conducted 2025 AHMP Kickoff Meetings
with internal stakeholders.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqiA]
OES Mitigation Division
NpNl^V_NLUA|AlLmpaINilaœ]NL
V_J]qLV_TIapU_ApqlA]VNwV]L]A_LœlN
NAlpUkqA\NNpJ A_LUq^A_-JAqmNLVN
JyINlmNJqlVpypNllalVm^NpJ
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
Group
Drafted initial sections of the 2025 AHMP . OEM AHMP Project Team
Shared drafts of initial sections with
internal and external stakeholders for
their review.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
Met with internal and external
stakeholders to obtain feedback on draft
plan elements.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
County of Los Angeles
All-Hazards Mitigation Plan
Date 3Am\m People Involved
March
2025
Developed the Public Outreach
Engagement Plan to collect feedback
from the public on the public draft of the
2025 AHMP .
OEM AHMP Project
3NA^A]%1
Mitigation Division
Drafted subsequent sections of the 2025
AHMP including updating existing
mitigation actions and developing new
mitigation actions as needed.
OEM AHMP Project
Team
Shared drafts of the subsequent sections
with internal and external stakeholders
for their review.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
Met with internal and external
stakeholders to obtain feedback on
subsequent draft plan elements.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
April/May
2025
lASpNLœ_A]mNJpVa_maSpUN
"-
and produced a Final Draft AHMP .
OEM AHMP Project
Team
Shared Final Draft of the AHMP with
internal and external stakeholders for
their review.
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
Met with internal and external
stakeholders to obtain feedback on
subsequent Final Draft AHMP .
OEM AHMP Project
3NA^_pNl_A]aq_py
1pA\NUa]LNllaqi
External Stakeholder
laqiA]%1
Mitigation Division
Produced Final AHMP . OEM AHMP Project
Team
County of Los Angeles
All-Hazards Mitigation Plan
2.2 Stakeholder Engagement
Inclusive stakeholder involvement was essential to the planning process. The County N_mqlNL IlaAL lNilNmN_pApVa_ A_L iAlpVJViApVa_ Ja_mVmpN_p wVpUp U N ´ : U a ] N a^^q_VpyiilaAJU´aqp]V_NLV_pUN%iNlApVa_A]lNA^NlTN_Jy%iNlApVa_m Plan (OAEOP). Key stakeholders that comprised the Hazard Mitigation Advisory Committee included:
• aq_pyLNiAlp^N_pmmqJUAmIqp_ap]V^VpNLpa-qI]VJ:al\m-qI]VJNA]pUA_L Regional Planning.
• Cities within the operational area (O A) and neighboring communities through Disaster Management Area Coordinators (DMACs) and city representation. • Non-TavNl_^N_pA] alTA_V|ApVa_m #%m V_J]qLV_T N_vVla_^N_pA] A_L disability advocacy groups.
• Special District partners managing critical infrastructure. • Representatives of academia and school districts.
• Community representatives from Access and Functional Needs (AFN) populations and historically underrepresented populations. 0NTq]Al^NNpV_Tmwal\mUaimA_LSaJqmTlaqimwNlNUN]LpaTApUNlV_iqpA_LlNœ_N mitigation strategies. Stakeholders were contacted and invited to participate in the 2025 AHMP planning process through email (please see email template in Appendix B-3). Stakeholder SNNLIAJ\wAmLaJq^N_pNLA_LV_JalialApNLV_papUNi]A_N_mqlV_T diverse perspectives informed the process. Tables 2-2 and 2-3 includes a list of representatives of each agency that contributed to the planning process.
Table 2-2 Hazard Mitigation Advisory Committee – _pNl_A]1pA\NUa]LNllaqi Department/
Agency
Name Title Planning Contribution
Los Angeles County
%SœJNaS
Emergency
Management (OEM
AHMP Project
Team)
Michael
Morin
Emergency
Management
Coordinator
q_JpVa_NLAm]NALi]A__Nlm
]NLi]A__V_T^NNpV_Tm
LlASpNLi]A_lNvVNwNL
mitigation actions submitted
by departments.
Matthew
Topoozian
Emergency
Management
Coordinator
County of Los Angeles
All-Hazards Mitigation Plan
Department/
Agency
Name Title Planning Contribution
Karen Haro Emergency
Management
Coordinator
Girma
Wollela
Emergency
Management
Coordinator
Los Angeles County
Department of
Aging and
Disabilities
Mike Tsao Administrative
Deputy
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Henry
Lopez
Program
Manager
Carin
Anderson
Administrative
Services
Manager
Keilah
Kelso
Administrative
Services
Manager
Los Angeles County
Chief Executive
%SœJN– Anti-
0AJVm^VvNlmVpy
and Inclusion
Initiative
Cesar
Sanchez
Senior Analyst ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Chief Executive
%SœJN– Homeless
Initiative
Onnie
Williams III
Principal Analyst ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Chief Sustainability
%SœJN
Matthew
Gosner
Climate
Resilience
%SœJNl
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
County of Los Angeles
All-Hazards Mitigation Plan
Department/
Agency
Name Title Planning Contribution
Los Angeles County
Department of
Beaches and
Harbors
Katharine
de la Cruz
Administrative
Services
Manager
Attended planning ^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Vanessa
Huerta
1ASNpy%SœJNl
Los Angeles County
Department of
Economic
Opportunity
Maritza
Dubie
Human Services
Administrator
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Department of
Health Services
Elaine
Forsyth
Senior Nursing
Instructor
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Isabel
Sanchez
Disaster
Services
Specialist
Los Angeles County
Department of
Human Resources
Kevin
Halbritter
Deputy
Compliance
%SœJNl
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Department of
Parks and
Recreation
Ramon
Bernal
Disaster
Services Analyst
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Department of
Public Health
Elizabeth
Rubin
Epidemiologist ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Department of
Public Social
Services
Manuel
Gutierrez
Disaster
Services Analyst
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
County of Los Angeles
All-Hazards Mitigation Plan
Department/
Agency
Name Title Planning Contribution
Los Angeles County
Department of
Public Works
Joseph
Marble
Disaster
Services Analyst
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Loni Eazell Disaster
Services
Specialist
Los Angeles County
Department of
Regional Planning
Thuy Hua Supervising
Planner
ppN_LNLi]A__V_T^NNpV_Tm
reviewed section LlASpmA_L
provided feedback.
Edgar De
La Torre
Principal
Regional
Planner
Los Angeles County
Fire Department
Nick
Duvally
Deputy Fire
Chief
ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Internal Services
Department
Juan-Raul
Cardenas
GIS Analyst ppN_LNLi]A__V_T^NNpV_Tm
lNvVNwNLmNJpVa_LlASpmA_L
provided feedback.
Los Angeles County
Sheriff’s
Department
Jordan
Kennedy
Sergeant ppN_LNLi]A__V_T^NNpV_Tm
reviewed section LlASpmA_L
provided feedback.
Table 2-3 Hazard Mitigation Advisory Committee – External 1pA\NUa]LNllaqi Department/Agency Planning Contribution
Access Services ppN_LNLi]A__V_T^NNpV_TmlNvVNwNLmNJpVa_ LlASpmA_LilavVLNLSNNLIAJ\
Alzheimer’s Association
California
ppN_LNLi]A__V_T^NNpV_TmlNvVNwNLmNJpVa_
LlASpmA_LilavVLNLSNNLIAJ\
A]VSal_VAavNl_al¯m%SœJN
of Emergency Services
ppN_LNLi]A__V_T^NNpV_TmlNvVNwNLmNJpVa_
LlASpmA_LilavVLNLSNNLIAJ\
Catholic Charities ppN_LNLi]A__V_T^NNpV_TmlNvVNwNLmNJpVa_ LlASpmA_LilavVLNLSNNLIAJ\
County of Los Angeles
All-Hazards Mitigation Plan