R-05-25, 2024 Update of the Cook County Multi-Jurisdictional Hazard Mitigation Plan4,18 Main Street I Lemont, li... 60439
THROUGH:
SUBJECT: 2024 Update of the Cook County Multi -Jurisdictional Hazard Mitigation
Plan
DATE: January 27, 2025
SUMMARY/BACKGROUND
Approval of the 2024 Update to the Cook County Multi -Jurisdictional Hazard Mitigation Plan is
a necessity in order for the Village to receive grant funds for various mitigation activities from
Federal and State entities in order to help protect our community from natural disasters, or
assist our community after one occurs. Once this plan update is adopted, the Village will
again be eligible to apply for hazard mitigation grant opportunities.
The Cook County Board of Commissioners adopted the Multi -Jurisdictional Hazard Mitigation
Plan in September 2014. The plan includes preventative and reactive steps to address
earthquakes, tornados, flooding and severe weather.
ANALYSIS
State statute requires all villages to periodically update their Hazard Mitigation Plan. Cook
County is asking all villages within the county to adopt the attached 2024 update to the Cook
County Multi -Jurisdictional Hazard Mitigation Plan. All villages must be compliant in order to
be eligible for grants. This plan is reviewed and updated every five years per statute.
Consistency with Village Policy
STAFF RECOMMENDATION
Staff recommends the approval to adopt the 2024 Update of the Cook County Multi -
Jurisdictional Hazard Mitigation Plan.
BOARD ACTION REQUESTED
Approval of the resolution to adopt the 2024 Update of the Cook County Multi -Jurisdictional
Hazard Mitigation Plan.
ATTACHMENTS
2024 Update of CCMJ Harzard Mitigation Plan and Addendums.pdf
Resolution. UpdateCookCountyMulti-JurisdictionalHazardMitigation Plan. 01.27.25.pdf
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2024 Cook County
Multi -Jurisdictional Hazard Mitigation Plan Update
Executive Summary
Hazard mitigation is the use of long-term and short-term policies, programs, projects, and other
activities to alleviate the death, injury, and property damage that can result from a disaster. Cook
County and a coalition of 125 municipal planning partners prepared and updated the 2024 Cook
County Multi -Jurisdictional Hazard Mitigation Plan in order to identify the risks posed by hazards
and find ways to reduce their impacts. The plan reduces risks for those who live in, work in, and
visit the County.
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Cook County is located in northeast Illinois on the western shore of Lake Michigan. It is the most
populous of the 102 counties in Illinois, with a 2013 estimated population of 5.24 million, 2018
estimated population of 5.18 million, and 2023 estimate of 5.08 million, according to the U.S.
Census Bureau and World Population Review. In terms of area, it is the sixth largest county,
covering approximately 946 square miles. Cook County makes up roughly 40 percent of the
population of Illinois. The surrounding counties are Lake and McHenry to the north, Kane, and
DuPage to the west, and Will to the southwest. Lake Michigan is the county's eastern border along
with the State of Indiana.
Cook County is the second most populous county in the United States, after Los Angeles County.
The county contains 135 municipalities, covering about 85 percent of the area of the county. The
remaining unincorporated areas are under the jurisdiction of the Cook County Board of
Commissioners, a 17-member board elected by district.
The economy of Cook County, IL employs 2.6 million people. The largest industries in Cook County
are Health Care & Social Assistance (365,461 people), Professional, Scientific, & Technical Services
(278,012 people), and Manufacturing (244,952 people), and the highest paying industries are
Utilities ($86,405), Finance & Insurance ($82,016), and Professional, Scientific, & Technical
Services ($80,988).
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Based on U.S. Census Bureau estimates, per capita income in the planning area in 2018 was
$32,722 and has increased to $45,646(in 2022 dollars) based on the ACS 2018-22. The median
household income (in 2022 dollars) is $78,304 based on the ACS 2022.
Cook County has experienced 22 hazard events since 1967 for which federal disaster declarations
were issued. The National Oceanic and Atmospheric Administration (NOAA) data is the primary
source utilized in the Hazard Mitigation Plan.
The responsibility for hazard mitigation lies with many, including private property owners;
business and industry; and local, state, and the federal government. Through multi -jurisdictional
partnerships, local jurisdictions within an area that has uniform risk exposure can pool resources
and eliminate redundant planning activities. Cook County opened this planning effort to all
municipalities within the County. The table, Planning Partners, lists the planning partners that
participated in the planning process and are covered under this plan. The planning area was
defined as all incorporated and unincorporated areas of Cook County as well as the incorporated
areas of cities that cross county boundaries. The planning area boundary is shown in the figure
below (Figure: Planning Area).
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Municipalities that are partially in Cook County and are participating in the mitigation planning
efforts of adjacent counties are also included in the table below. Future efforts are already
underway to include these jurisdictions in future updates of the plan. Two jurisdictions that had not
previously participated in the 2019 Cook County MJ-HMP are now part of the 2024 Cook County MJ-
HMP.
TABLE: PLANNING PARTNERS
PLANNING PARTNERS COVERED BYTHIS HAZARD MITIGATION PLAN
North
Central
South
Arlington Heights
Bellwood
Alsip
Barrington
Berkeley
Bedford Park
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Buffalo Grove
Berwyn
Blue Island
Des Plaines
Broadview
Bridgeview
Elgin
Burbank
Elk Grove Village
_Brookfield
City of Chicago
Burnham
Evanston
Cicero
Calumet City
Glencoe
Countryside
Calumet Park
Glenview
Elmwood Park
Chicago Heights
Golf
Forest Park
Chicago Ridge
Hanover Park
Forest View
Country Club Hills
Hoffman Estates
Franklin Park
Crestwood
Inverness
Harwood Heights
Dixmoor
Kenilworth
Hillside
Dolton
Lincolnwood
Hodgkins
East Hazel Crest
Morton Grove
Indian Head Park
Evergreen Park
Mount Prospect
LaGrange
Flossmoor
Niles
LaGrange Park
Ford Heights
Northbrook
Lyons
Glenwood
Northfield
Maywood
Harvey
Palatine
McCook
Hazel Crest
Park Ridge
Melrose Park
Hickory Hills
Prospect Heights
Norridge
Hometown
Rolling Meadows
Northlake
Homewood
Schaumburg
North Riverside
Justice
Skokie
Oak Park
Lansing
South Barrington
River Forest
Lemont
Streamwood
River Grove
Lynwood
Wheeling
Riverside
Markham
Wilmette
Rosemont
Matteson
Winnetka
Schiller Park
Merrionette Park
Stickney
Midlothian
Stone Park
Oak Forest
Summit
Oak Lawn
Westchester
Olympia Fields
Western Springs
Orland Hills
Orland Park
Palos Heights
Palos Hills
Palos Park
Park Forest
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Phoenix
Posen
Richton Park
Riverdale
Robbins
Sauk Viltage
South Chicago Heights
South Holland
Steger
Thornton
Tinley Park
University Park
Willow Springs
Worth
Not Participating in 2024
Cook County MJ-HMP
Not Participating in 2024
Cook County MJ-HMP
Not Participating in 2024
Cook County MJ-HMP
Barrington Hills
Bensenville
Frankfort
Bartlett
Burr Ridge
Woodridge
Deerfield
Elmhurst
Deer Park
Hinsdale
East Dundee
Oak Brook
Roselle
The 2024 Cook County MJ-HMP was updated by a planning team of Cook County Department of
Emergency Management and Regional Security staff and expert consultants, with guidance from a
steering committee representing the planning partners and other local stakeholders. The key
steps in updating the plan were as follows:
1. Determine the Planning Area and Resources
2. Build and Reconvene the Planning Team
3. Outreach Strategy
4. Review and Update Community Capabilities
5. Update and Conduct the Risk Assessment
6. Update the Mitigation Strategy
7. Keep the Plan Current
8. Review and Adopt the Plan
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9. Create a Safe and Resilient Community
® Mission Goals and Objectives
The defined mission for the 2024 Cook County MJ-HMP is to "Identify risks and sustainable,
cost-effective actions to mitigate the impact of natural hazards to protect the life, health, safety,
welfare, and economy of the communities of Cook County." Mitigation goals were established as
follows:
1. Develop and implement sustainable, cost-effective, and environmentally sound risk -
reduction (mitigation) projects.
2. Protect the lives, health, safety, and property of the citizens of Cook County from the
impacts of natural hazards.
3. Protect public services and critical facilities, including infrastructure, from loss of use during
natural hazard events and potential damage from such events.
4. Involve stakeholders to enhance the local capacity to mitigate, prepare for, and respond to
the impacts of natural hazards.
5. Develop, promote, and integrate mitigation action plans.
6. Promote public understanding of and support for hazard mitigation.
Thirteen objectives were established for the plan that meets multiple goals, serving as stand-
alone measurements of. the effectiveness of the mitigation action. Proposed mitigation actions
were evaluated in part based on how many goals and objectives they would help to fulfill.
1. Eliminate or minimize disruption of local government operations caused by natural hazards
through all phases of emergency management.
2. Increase the resilience of (or protect and maintain) infrastructure and critical facilities.
3. Consider the impacts of natural hazards on future land uses in the planning area, including
possible impacts from climate change.
4. Integrate hazard mitigation policies into land use plans in the planning area.
5. Develop, improve, and protect systems that provide early warnings, emergency response
communications, and evacuation procedures.
6. Use the best available data, science and technologies to educate the public and to improve
understanding of the location and potential impacts of natural hazards, the vulnerability of
building types and community development patterns, and the measures needed to protect
life safety.
7. Retrofit, purchase, or relocate structures in high hazard areas, including those known to be
repetitively damaged.
Establish partnerships among all levels of local government, the private sector, and/or
nongovernmental organizations to improve and implement methods to protect people,
including underserved and underrepresented groups, and property.
9. Provide or improve flood protection on a watershed basis with flood control structures and
drainage maintenance plans.
10. Strengthen codes and land use planning and their enforcement, so that new construction
or redevelopment can avoid or withstand the impacts of natural hazards.
11. Encourage mitigation through incentive -based programs, such as the Community Rating
System, Firewise, and StormReady programs.
12. Reduce natural hazard -related risks and vulnerability to potentially isolated and
underserved populations within the planning area and ensure mitigation strategies result in
equitable outcomes.
13. Encourage hazard mitigation measures that result in the least adverse effect on the natural
environment and that use natural processes.
® Hazards
The steering committee considered the full range of natural hazards that could impact the
planning area and identified the following hazards as presenting the most significant concern:
• Dam or levee failure
• Drought
• Earthquake
• Flood
• Severe weather
• Severe winter weather
• Tornado
• Wildfire
Detailed risk assessments were performed for each of these hazards of concern. Also, a brief
qualitative review was conducted of technological and human -caused hazards of interest. Climate
Change was addressed for each hazard, as applicable.
6. Risk Assessment Methodology
Risk assessment is the process of measuring the potential loss of life, personal injury, economic
injury, and property damage resulting from natural hazards. It allows emergency management
personnel to establish early response priorities by identifying potential hazards and vulnerable
assets. The process focuses on the following elements:
• Identify hazards —Use all available information to determine what types of disasters may
affect a jurisdiction, how often they can occur, and their potential severity.
• Assess probability, extent, vulnerability, and impact —Determine the impact of natural
hazard events on the people, property, environment, economy, and lands of the region.
• Estimate cost —Estimate the cost of potential damage that could be avoided by mitigation.
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The risk assessment for this hazard mitigation plan evaluates the risk of natural hazards prevalent
in the planning area and meets requirements of the OMA(44 CFR, Section 201.6(cX2)).
® Profiles of Cook County Hazards of Concern
The following hazards are addressed in the 2024 Cook County MJ-HMP. A brief description of each
hazard is included in this section of the Executive Summary.
7.1 Dam and Levee Failure
There are 44 dams in Cook County, all regulated by the Water Resources Division of the Illinois
Department of Natural Resources (IDNR). Importantly, 23 of these dams are classified as "high"(11)
or "significant" (12) hazard, which means they have significant downstream populations at risk if the
dam should fail. Flooding as a result of a dam and levee failure would significantly impact
properties and communities in the inundation zones. There is no record of Federal Dam Disaster
Declarations in Cook County between 1956-2022.
According to the National Inventory of Levees, there are seven (7) major levee systems located in
Cook County (National Inventory of Levees). Although there is no history of levee failures in the
planning area, it should be noted that the State of Illinois experienced levee failures in 1993 and
2008. In 1993,17levee systems breached along the Mississippi River and the Illinois River just north
of where it meets the Mississippi River. Over 237,000 acres along the rivers were flooded.
Dam or levee failure can have severe impacts on property and critical infrastructure. These
impacts include:
• Extensive Property Damage: The sudden release of water from a dam or levee failure can
lead to widespread flooding, resulting in significant damage to residential, commercial, and
industrial properties. This includes damage to buildings, homes, and vehicles.
• Critical Infrastructure Damage: Flooding from dam or levee failures can severely impact
critical infrastructure such as bridges, roads, railways, and utilities (water and sewage
systems, electrical grids, gas lines). This not only causes immediate disruption but can also
lead to long-term economic impacts due to the time and cost associated with repairs and
reconstruction.
• Environmental Contamination: Floodwaters can carry and spread pollutants and hazardous
materials from industrial sites, sewage systems, and other sources, leading to
environmental contamination of water, soil, and ecosystems.
• Disruption of Services: Essential services such as healthcare, education, emergency
services, and transportation can be disrupted, affecting the wellbeing and daily life of the
community.
• Economic Impact: The combined effect on property, infrastructure, and services can lead
to significant economic losses, both direct and indirect. The cost of repairs, loss of
business operations, and decrease in property values can have a lasting impact on affected
communities.
• Recovery and Mitigation Costs: The financial burden of recovery and rebuilding can be
substantial. In addition to immediate repair costs, there is often a need for investing in
mitigation measures to prevent future incidents.
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Exposed Structures and Property Value
FEMA's HAZUS-MH model estimated that there are 12,762 structures within the mapped dam
failure inundation areas in the planning area. It is estimated that $10.7 billion worth of building -
and -contents are exposed to dam failure inundation, representing 0.90 percent of the total
building value of the planning area.
7.2 Drought
Droughts originate from a deficiency of precipitation resulting from an unusual weather pattern. If
the weather pattern lasts a short time (a few weeks or a couple of months), the drought is
considered short-term. If the weather pattern becomes entrenched and the precipitation deficits
last for several months or years, the drought is considered to be long-term. Drought generally
affects large geographic areas, so drought descriptions in the hazard mitigation plan are usually
for the entire State of Illinois rather than the immediate planning area of Cook County.
Droughts are fairly common in Illinois. In the past century, the state experienced serious drought
periods from 1902 to 1915, from 1931 to 1934, and in 1954,1964, and 1988. The 1930s had the greatest
frequency and severity of drought since drought recording using the Palmer Drought Severity
Index(PDSI) began in 1895. The worst case was the summer of 1934, with a statewide PDSI of -6.48,
followed by the summer of 1931 with -6.39 and 1954 with -6.09. All three of these events fall into the
category of extreme drought.
Recent events include drought in 1983 and 1988. In September 1983, all 102 counties were declared
state disaster areas because of high temperatures and insufficient precipitation during the
summer. In 1988, 54 percent of the state was impacted by drought -like conditions, resulting in
disaster relief payments to landowners and farmers exceeding $382 million; however, no state
declaration was made. Historical drought data for the planning area indicate there have been at
least seven (7) significant droughts in the last 115 years, which equates to a drought every 16 years
on average, or a minimum of a 6.25-percent chance of a drought in any given year.
Drought can have a widespread impact on the environment and the economy, although it typically
does not result in loss of life or damage to property, as do other natural disasters. The National
Drought Mitigation Center describes likely drought impacts as those affecting agriculture, water
supplies, and the risk of fire.
Scientists currently do not know how to predict drought more than a month in advance for most
locations. How long a drought lasts depends on interactions between the atmosphere and the
oceans, soil moisture and land surface processes, topography, internal dynamics, and the
accumulated influence of weather systems on the global scale.
Crucial issues associated with drought include the following:
• Identification and development of alternative water supplies
• Use of groundwater recharge techniques to stabilize the groundwater supply
• The probability of increased drought frequencies and durations due to climate change
• The promotion of active water conservation even during non -drought periods.
While drought is considered a low -risk hazard for Cook County, planners need to consider best
practices for land use policies to support water supply sustainability and increase the protection
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of water resources. Utilizing these practices provides local municipality capability to protect
future development from drought.
7.3. Earthquake
An earthquake is the vibration of the earth's surface following a release of energy in the earth's
crust. Earthquakes tend to occur along faults, which are zones of weakness in the crust.
Earthquakes occur throughout Illinois, with most in the southern third of the state. Over 360
earthquakes have occurred in Illinois during the past 20 years, with 32 resulting in damage.
According to USGS, no fault zones are in Cook County; however, numerous reports highlight the
fault activity of the Des Plaines Crater located beneath the populated Des Plaines suburb of
Chicago. Fifteen events have been recorded in Cook, DuPage, Kane, Kendall, and Will Counties
since 1704. Cook County has experienced three earthquakes ranging from a magnitude of 3 to 4.9.
Since the 2018 Hazard Mitigation Plan, Cook County has not experienced any additional significant
earthquakes.
The actual movement of the ground in an earthquake is seldom the direct cause of injury or death.
Casualties generally result from falling objects and debris, because the shocks shake, damage or
demolish buildings and other structures. Disruption of communications, electrical power supplies
and gas, sewer and water lines should be expected. Earthquakes may trigger fires, dam failures, or
releases of hazardous material, compounding their effects. Any seismic activity of 6.0 or greater
on faults within the planning area would have significant impacts throughout the county.
Earthquakes of this magnitude or higher would lead to a massive failure of structures built on loose
soils. Levees and revetments constructed on such soils would likely fail, representing a loss of
critical infrastructure. These events could cause secondary hazards that would further damage
structures.
There is currently no reliable way to predict an earthquake at any given location with any
significant warning time. Research is being done with warning systems that use the low energy
waves that precede major earthquakes to give approximately 40 seconds notice that a major
earthquake is about to occur. The warning time is very short, but it could allow for someone to get
under a desk, step away from a hazardous material they are working with or shut down a computer
system.
Important issues associated with earthquakes include the following:
• The public perception of the earthquake risk within the planning area is low. It can be
difficult to get the public to think about earthquake mitigation with little or no perceived
risk.
• Most of the planning area's building stock was built prior to 1975 when seismic provisions
became uniformly applied through building code applications. A building stock analysis that
looks at the potential fragility of the older building stock constructed without building code
influence would be beneficial in the identification of seismic mitigation projects.
• More earthquake mapping is needed for the planning area.
• Critical facility owners/operators should be encouraged to create or enhance continuity of
operations plans using the information on risk and vulnerability contained in the Cook
County hazard mitigation plan.
• Geotechnical standards should be established that take into account the probable impacts
of earthquakes in the design and construction of new or enhanced facilities.
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The County has over 6 miles of earthen levees and revetments on soft, unstable soil. These
soils are prone to liquefaction, which would severely undermine the integrity of these
facilities.
There are a large number of earthen dams within the planning area. Dam failure warning
and evacuation plans and procedures should be reviewed and updated to reflect the dams'
risk potential associated with earthquake activity in the region.
7.4 Flood
Flood Types and History
Flooding can occur in a number of ways, and many instances are not independent of each other and
can occur simultaneously during a flood event. The types of flooding considered forthis plan include:
• Heavy rainfall
• Urban stormwater overflow
• Rapid snowmelt
• Rising groundwater (generally in conjunction with heavy prolonged rainfall and saturated
conditions)
• Riverine ice jams
• Flash floods
• Alluvial fan flooding
• Flooding from dam failure
• Coastal/Shoreline flooding
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o Meteotsunami
o Coastal Erosion
Floods in Cook County are caused by rainfall from large frontal storms, which may be in
combination with some snowmelt, runoff, and icejams. The principal contributorto flooding in the
area is the inadequate capacity of some of the natural stream channels to contain runoff resulting
from intense thunderstorm precipitation over the stream basins. Inundation of lands adjoining
stream channels has been aggravated over the years by the gradual accumulation of silt. The
buildup of sand bars and island channels has resulted in the loss of channel capacity. Another
factor lending itself to the poor flow characteristics of some portions of channels is the excessive
growth of brush, light timber, and aquatic vegetation.
From 2013 through 2022, 90 Riverine Flooding incidents occurred in Cook County and were
recorded by NOAA. This frequency averages nine flooding incidents annually and would indicate a
similar trend moving forward. From 2013 through 2022, 84 Urban/ Flash/ Stormwater Flooding
incidents occurred in Cook County and were recorded by NOAA. This frequency averages 8.4
flooding incidents annually and would indicate a similar trend moving forward.
According to NOAA, the frequency of flash flooding depends on seasonal weather patterns. Flash
flooding is typically caused by inadequate drainage following heavy rainfall or rapid snowmelt and
is more likely to occur in spring when thunderstorms and snow melt are more prominent.
Urban areas (such as Chicago) are typically connected to municipal sewer systems (stormwater
and/or sanitary sewer). For this reason, it is more probable that flash flooding will occur within this
area.
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Cook County experiences numerous episodes of river and urban flooding every year; massive
floods that can cause significant property damage typically occur every three to seven years.
Flood Mapping
Flood stUdies use historical records to determine the probability of occurrence for different river
discharge (flow) levels. The flood frequency equals 100 divided by the discharge probability. For
example, the 100-year discharge has a 1-percent chance of being equaled or exceeded in any given
year. The extent of flooding associated with a 1-percent annual probability of occurrence (the base
flood or 100-year flood) is used as a regulatory boundary by many agencies. This boundary is a
convenient tool for assessing risk in flood -prone communities. For most communities
participating in the National Flood Insurance Program (NFIP), FEMA has prepared a detailed Flood
Insurance Study that presents water surface elevations for the 1- percent annual chance flood and
the 0.2-percent annual chance flood (the 500-year flood). The federal standard for floodplain
management under the NFIP is the 100-year floodplain. This area is chosen using historical data
such that in any given year there is a 1% chance of a "base flood (also known as 100-year flood or
regulatory flood). A base flood is one that covers or exceeds the 100-year floodplain. A 500-year
floodplain is an area with at least a .2% chance of flood occurrence in any given year. The
boundaries of the 100- and 500-year floodplains are shown on Flood Insurance Rate Maps.
FEMA has mapped over 78 square miles of the 100-year floodplain and 99 square miles of 500-year
floodplain along 172 water courses within the Cook County planning area. This includes floodplains
within jurisdictions that intersect multiple counties. Whiles these maps do not cover all the flood
risks within the planning area, they do represent a large percentage of the risk. It should be noted
that mapping showing areas of urban flooding is limited in the County.
Flood Severity
The principal factors affecting flood damage are flood depth and velocity. The deeper and faster
flood flows become, the more damage they can cause. Shallow flooding with high velocities can
cause as much damage as deep flooding with slow velocity, is especially true when a channel
migrates over a broad floodplain, redirecting high -velocity flows and transporting debris and
sediment. Flood severity is often evaluated by examining peak discharges.
The worst -case scenario for flooding in the Cook County planning area has happened numerous
times in the past. It involves intense rainstorms that stall over the planning area, dropping rainfall
totals in excess 6 inches over 48 hours (this scenario is significantly exacerbated by the presence
of snowpack on the ground), which leads to both riverine and stormwater/urban drainage flooding
that can overwhelm flood response capabilities in the planning area. Significant roads can be
blocked, preventing critical access for many residents and critical functions. High in -channel flows
can cause water courses to scour, possibly washing out roads and creating more isolation
problems.
Flood Warning
The Cook County flood threat system consists of a network of precipitation gages throughout the
watershed and stream gages at strategic locations that continuously monitor and report stream
levels. All of this information is analyzed by agencies such as the Cook County Department of
Emergency Management and Regional Security (EMRS) and Metropolitan Water Reclamation
District to evaluate the flood threat and possible evacuation needs.
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Floods are generally classed as either slow -rise or flash floods. Due to the sequential pattern of
meteorological conditions needed to cause serious slow -rise flooding, it is unusual fora slow -rise
flood to occur without warning. Slow -rise floods maybe preceded by a warning time from several
hours, to days, to possibly weeks. Evacuation and sandbagging fora slow -rise flood may lessen
flood damage. Flash floods are more difficult to prepare for, due to the extremely short warning
time given, if any. Flash flood warnings usually require evacuation within an hour. However,
potential hazard areas can be warned in advance of potential flash flooding danger.
Participation in FederalRoodPrograms
The NFIP makes federally backed flood insurance available to homeowners, renters, and business
owners in participating communities. Cook County entered the NFIP on April 15,1981. The effective
date for the current countywide Flood Insurance Rate Map is August 19, 2008. In addition to the
County, most Cook County municipalities participate in the NFIP. As of August 2023, Cook County
had 12,083 flood insurance policies providing $2.644 billion in insurance coverage. According to
FEMA statistics, in the State of Illinois, there were 32,840 flood insurance policies providing over
$7.06 billion in insurance coverage.
As of March 17, 2022, there are twenty (20) communities in the planning area that also participate
in the Community Rating System (CRS), a voluntary program that encourages floodplain
management activities that exceed the NFIP requirements. The CRS requires participating
communities to identify repetitive loss areas, where flood insurance claims have been paid
multiple times for individual properties. FEMA's list of repetitive loss properties identifies 1,741
such properties in the planning area as of May 2024.
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Important issues associated with flooding include the following:
• Modeling performed by the Metropolitan Water Reclamation District is considered to be the
best available flood risk data for the planning area, but it is not the basis of FEMA's current
effective Flood Insurance Rate Map. The District's flood hazard data should be formatted so
that can be used to support risk assessment and thus validate the best available data.
• The planning area has a large percentage of policies and losses outside a mapped hazard
area. Basement flooding is a common problem.
• The stormwaterlurban drainage flooding risk is not mapped, which makes it difficult to
assess this hazard, other than looking at historical loss data.
• The risk associated with the flood hazard overlaps the risk associated with other hazards
such as an earthquake. This provides an opportunity to seek mitigation alternatives with
multiple objectives that can reduce the risk for multiple hazards.
• There is no consistency of land -use practices and regulatory floodplain management
within the planning area. It is unclear how potential climate change may impact flood
conditions in the planning area.
• The concept of residual risk should be considered in the design of future capital flood
control projects and should be communicated with residents living in the floodplain.
• More information is needed on flood risk to support the concept of risk -based analysis of
capital projects.
• There needs to be a sustained effort to gather historical damage data, such as high-water
marks on structures and damage reports, to measure the cost-effectiveness of future
mitigation projects.
13
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• Ongoing flood hazard mitigation will require funding from multiple sources.
• There needs to be a coordinated hazard mitigation effort between jurisdictions affected by
flood hazards in the county.
• Flood plain residents need to continue to be educated about flood preparedness and the
resources available during and after floods.
• The promotion of flood insurance as a means of protecting private property owners from
the economic impacts of frequent flood events should continue.
• The economy affects a jurisdiction's ability to manage its flood plains. Budget cuts and
personnel losses can strain the resources needed to support floodplain management.
7.5 Severe Weather
Severe weather refers to any dangerous meteorological phenomena with the potential to cause
damage, serious social disruption, or loss of human life. It includes extreme heat, lightning,
hailstorms, dense fog, and strong wind. Severe -weather events can happen anywhere in the
planning area. Severe local storms are probably the most common widespread hazard. They affect
large numbers of people throughout Cook County and the surrounding region when they occur. The
heat wave of July 1995 was one of the worst disasters in Illinois history, with over 700 deaths
statewide over five days.
Records from the National Climatic Data Center indicate approximately 1,410 severe weather
events (not including heat and excessive heat events) in the planning area between 1950 and 2023.
NCDC data from 1996 to 2023 also records 64 heat or excessive heat events.
The most common problems associated with severe storms are immobility and loss of utilities.
Roads may become impassable due to flooding or downed trees. Power lines may be downed due
to high winds. Lightning can cause severe damage and injury. A worst -case severe -weather event
would involve prolonged high winds during a thunderstorm. Such an event would have both short-
term and longer -term effects. Initially, schools and roads would be closed due to power outages
caused by high winds and downed tree obstructions. In more rural areas, some subdivisions could
experience limited ingress and egress. Prolonged rain could produce flooding and overtopped
culverts with ponded water on roads. Flooding could further obstruct roads and bridges, further
isolating residents.
Meteorologists can often predict the likelihood of a severe storm or other severe weather events,
which can give several days of warning time. The Chicago Office of the National Weather Service
issues severe storm watches and warnings when appropriate to alert government agencies and
the public of possible or impending weather events.
Important issues associated with severe weather include the following:
• Redundancy of power supply throughout the planning area must be evaluated. The capacity
for backup power generation is limited.
• Public education on dealing with the impacts of severe weather needs to be provided and
debris management (downed trees, etc.) must be addressed.
• The effects of climate change may result in an increase in the frequency of extreme heat
events.
14
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The severe winter weather hazard encompasses heavy snow, lake -effect snow, blizzards, ice
storms, sleet, cold/windchill, extreme cold temperatures and wind chill, frost/freeze, general
winter weather, and winter storms. Severe winter weather events can happen anywhere in the
planning area. NOAA identifies 181 of these severe winter weather events in the planning area from
1950 - 2023, excluding snowstorms classified as less than major snowstorms. The planning area
typically receives 34 inches of snow each year and can expect to experience exposure to a severe
winter weather event at least annually.
All events totaled $700,000 in property damage,156 direct deaths and 8 indirect deaths, and 5
direct injuries and 3 indirect injuries.
Severe winter weather impacts can be significant. Roads may become impassable due to ice or
snow. Power lines may be down due to high winds or ice accumulation, and services such as water
or phone may not be able to operate without power. Physical damage to homes and facilities can
occur from wind damage or accumulation of snow or ice. Freezing rain can cause the most
dangerous conditions. Ice buildup can bring down trees, communication towers, and wires,
creating hazards for property owners, motorists, and pedestrians alike. Many severe winter
weather events in the planning area have resulted in the loss of life.
Meteorologists can often predict likely severe winter weather, giving several days of warning time.
The National Weather Service provides public warnings on storm, snow and ice events as
appropriate to alert government agencies and the public of possible or impending weather events.
Important issues associated with severe winter weather in the planning area include the following:
• Heavy snow can lead to structural damage due to the weight of snow accumulation,
especially on roofs and overhangs. This can result in costly repairs and safety hazards.
• The weight of snow and ice can down trees and power lines, leading to widespread power
outages. This disrupts heating and telecommunications and can cause further economic
losses. Redundancy of power supply must be evaluated as the capacity for backup power
generation is limited.
• Extreme cold/wind chill can lead to property damage and critical infrastructure impacts
including frozen and burst water pipes.
• Isolated and vulnerable populations are at significant risk.
e7 Tornado
Tornadoes are the most violent of all atmospheric storms, and all of Illinois is susceptible to them,
including Cook County. The tornado season runs March through August, although a tornado can
occur in the state at any time. Many tornadoes have struck Cook County, including several within
the Chicago city limits. The F4-rated Oak Lawn tornado in April 1967 was one of the deadliest
tornadoes in the planning area, with 33 fatalities. The only F5 tornado to ever strike the Chicago
area was on August 28,1990, which occurred in nearby Will and Kendall Counties. In total, 29 direct
deaths, 350 injuries, and 250 million in property damage was recorded.
Between 01/O1/2014 and 12/31/2023 Cook County recorded 16 tornadic events over 3,652 days.
15
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<ti��Y #�: u� tier^ i;�I;�{,�.✓r��4�.,.. ..,.a,UUfrV��I�Y� fEGU`I LIY:C'` UIntF\
Tornadoes can cause fatalities and devastate a neighborhood in seconds. Winds can reach 300
mph, and damage paths can be more than a mile wide and 50 miles long. If a major tornado were to
strike within the populated areas of Cook County, the damage could be widespread. Businesses
could be forced to close for an extended period or permanently, fatalities could be high, many
people could be homeless for an extended period, and routine services such as telephone or power
could be disrupted. Buildings can be damaged or destroyed.
The local NWS office issues a tornado watch when tornadoes are possible in an area and a tornado
warning when a tornado has been sighted or indicated by weather radar. The current average lead
time for tornado warnings is 13 minutes. The National Weather Service has established a goal of 15
minutes in its strategic plan. Occasionally, tornadoes develop so rapidly that little, if any, advance
warning is possible.
Important issues associated with tornadoes in the planning area include the following:
• The older building stock in the planning area is built to low code standards or none at all.
These structures could be highly vulnerable to tornadoes.
• Redundancy of power supply must be evaluated. The capacity for backup power generation
is limited.
• The amount of the tornado zone that contains vacant, developable land is not known and
would be valuable information for gauging the future development potential of the tornado
zone.
• Declining growth rate makes it difficult for code standards to have impacts on new
development. The planning area has insufficient suitable tornado shelters.
• Public awareness of tornado response protocols is a concern, given the area's many
visitors.
7.8 Wildfire
Wildfire is an uncontrolled fire that burns in forests, grasslands, and other natural areas. Wildfires
can spread quickly, driven by factors like wind and dry conditions, and they often pose significant
threats to life, property, and the environment. These fires can be ignited by various sources,
including lightning, human activities, and other natural causes. Wildfires can result in widespread
devastation and require coordinated efforts for containment, suppression, and recovery.
The National Interagency Fire Center(NIFC) employs several measures and tools to assess the
extent and intensity of wildfires. These include the acreage burned, which quantifies the size of
the affected area, with larger acreage indicating more extensive wildfires. Fire behavior indicators
such as the rate of spread, fireline intensity, and flame length offer insights into the wildfire's
intensity, with rapid spread and high -intensity flames signifying a more severe fire.
Although wildfires are not a major risk for Cook County, locations within the Forest Preserves of
Cook County may be vulnerable to this hazard. Air quality concerns from wildfires outside of Cook
County also pose a risk.
Wildfires can have significant life safety and public health impacts. First, wildfires produce smoke
and particulate matter that can degrade air quality over large areas, potentially leading to
respiratory issues, exacerbating pre-existing conditions, and causing symptoms such as coughing,
shortness of breath, and irritation of the eyes and throat.
16
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® Planning Area RiskRanking
Risk rankings were performed by each planning partner to compare the probable impacts of
the hazards of concern. For each community, the rankings assessed the probability of each
hazard's occurrence as well as its likely impact on people, property, and the economy. The
results of the countywide ranking, which were used in establishing mitigation action and
priorities, are summarized below.
•® e
14M, c$
(�
p4
HazardEvent
s
_
Flood (Urban/Flash 3 15 12
30 57 79
Flood)
Severe Winter
3
15
16
24
55
77
Weather: Blizzards
Severe Winter
3
12
16
21
49
70
Weather: Snow
Severe Weather:
3
9
16
16
41
60
High Winds
Flood
2
15
11
31
57
56
(Rive rine/Creek)
Severe Winter
2
15
16
25
56
55
Weather: Ice Storms
Severe Weather:
2
12
12
30
54
54
Extreme Heat
Tornado
2
15
6
30
51
51
Severe Winter
Weather: Extreme
2
12
12
20
44
45
Cold
Drought
2
12
12
18
42
43
Coastal/Shoreline
2
12
6
23
41
42
Flooding
Earthquake
2
9
16
16
41
42
Severe Weather:
3
6
6
14
26
41
Lightning
Severe Weather. Hail
2
9
11
16
36
38
Severe Weather: Fog
2
9
6
14
29
32
Wildfire
2
6
6 _
15
27
30
17
Dam and levee
1
15
6
27
48
27
failure
® Mitigation Strategies
The heart of the mitigation plan is the mitigation strategy, which serves as the long-term blueprint
for reducing the potential losses identified in the risk assessment. The mitigation strategy
describes how Cook County and the participating jurisdictions will accomplish the overall purpose,
or mission, of the planning process. As part of the update process, mitigation goals and objectives
were reevaluated; and mitigation actions/projects were updated/amended, identified, evaluated,
and prioritized. Over 1,500 mitigation projects were identified and updated by the County and
participating jurisdictions.
10. Plan MaintenanceStrategy
The hazard mitigation plan includes a formal process to ensure that the 2024 Cook County MJ-HMP
remains an active and relevant document and that the planning partners maintain their eligibility
for relevant funding sources. The plan's format allows sections to be reviewed and updated when
new data becomes available, resulting in a plan that will remain current and relevant. The strategy
for ongoing maintenance of the plan includes the following components:
Plan Implementation —Plan implementation and evaluation will be a shared responsibility among all
planning partners and agencies identified as lead agencies in the mitigation action plans. Cook
County EMRS will assume lead responsibility for implementing the plan maintenance strategy.
Steering Committee —It is recommended that a steering committee remain a viable body involved
in key elements of the plan maintenance strategy. The steering committee will strive to include
representation from the planning partners, as well as other stakeholders in the planning area.
Annual Progress Report —The steering committee will convene to perform annual reviews. EMRS
will then prepare a formal annual report on the progress of the plan.
Plan Update —The planning partnership intends to update the hazard mitigation plan on a five-year
cycle from the date of initial plan adoption.
Continuing Public Involvement —The public will continue to be apprised of the plan's progress
through the Cook County hazard mitigation website and by copies of annual progress reports
provided to the media. EMRS has agreed to maintain the hazard mitigation plan website, and each
planning partner has agreed to provide links to the website on their jurisdictional websites.
Incorporation into Other Planning Mechanisms —All municipal planning partners are committed to
creating a linkage between the hazard mitigation plan and their comprehensive plans by identifying
a mitigation action as such and giving that action a high priority. As information becomes available
from other planning mechanisms that can enhance this plan, that information will be incorporated
via the update process.
18
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11® Plan Adoption
The 2024 Cook County MJ-HMP was submitted for review and approval to the Illinois Emergency
Management Agency and FEMA in June of 2024. The 2024 update of the Cook County Multi -
Jurisdictional Hazard Mitigation Plan (CCMJHMP) was approved by IEMA and FEMA in July and has
been officially adopted by the Cook County Board of Commissioners. The next step in the process
is for all participating jurisdictions to officially adopt the plan through resolution. Every
participating jurisdiction must adopt the Cook County Plan through resolution within 1 year to be
officially recognized by FEMA as being part of the CCMJHMP.
19
CO o K
COOK COUNTY
P
O O
EMRS
-V- 5'
t
EMERGENCY MANAGEMENT
` `" °
AND REGIONAL SECURITY
Cook County Multi -Jurisdictional Hazard
WHAT IS THIS
Mitigation Plan Update
PLAN?
Executive Overview 2024
Mitigation is defined in this
context as any sustained action
The Cook County Multi -Jurisdictional Hazard Mitigation Plan
taken to reduce or eliminate
(CCMJHMP) was submitted to the Illinois Emergency
long-term risk to life and
Management Agency(IEMA) for review and approval pending
property from a hazard event.
adoption. FEMA guidance (Disaster Mitigation Act of 2000)
Mitigation planning is the
requires that the CCMJHMP be updated every 5 years. Cook
systematic process of learning
County Emergency Management and Regional Security(EMRS)
about the hazards that can
updated the 2019 CCMJHMP, which now includes 125
affect the community, setting
participating jurisdictions/partners, making Cook County's plan
clear goals, identifying
the largest in the nation. The planning area for the hazard
appropriate actions and
mitigation plan encompasses Cook County and includes the
following through with an
incorporated and unincorporated jurisdictional areas of the
effective mitigation strategy.
County and the Metropolitan Water Reclamation District of
Mitigation encourages long -
Greater Chicago (MWRD) service area and Cook County Forest
term reduction hazard
Preserve. The result of these combined efforts has been to
vulnerability andd can reduce the
produce an Illinois Emergency Management Agency (IEMA)and
enormous costdisasters to
Federal Emergency Management Agency(FEMA)approved
property ownerss and all levels
Hazard Mitigation Plan (HMP).
of government. Mitigation can
Adoption of the CCMJHMP makes participants eligible to apply
also protect critical community
for grants funds through the FEMA Hazard Mitigation Assistance
facilities, reduce exposure to
Program. FEMA requires that each participating partner adopt
liability and minimize post -
the plan by resolution.
disaster community disruption.
The following represent key elements from the 2024 CCMJHMP
update:
WHY IS THIS PLAN
• 125 total jurisdictions/partners participated in the 2024
SO IMPORTANT?
Cook County Multi -Jurisdictional Hazard Mitigation Plan
(CCMJHMP).
• The hazard identification and profiling in the hazard
Adoption of the CCMJHMP
mitigation plan addresses the following natural hazards
makes participants eligible to
considered to be of paramount importance within Cook
apply for grants funds through
the FEMA Hazard Mitigation
Assistance Program.
County. It is important to note that the Disaster Mitigation Act of 2000 requires that all
"natural hazards' be addressed in this plan. They are dam or levee failure, drought,
earthquake, flood, severe weather, severe winter weather, tornado, and wildfire.
Over 1,500 mitigation projects were identified and updated by Cook County and
participating jurisdictions.
Two jurisdictions that had not previously participated in the 2019 CCMJHMP are now part of
the 2024 plan.
14 of the jurisdictions that opted not to participate in this year's plan represent
jurisdictions that reside geographically in multiple counties and are participating in
neighboring county plans.
The CCMJHMP consists of 2 Volumes:
• Volume 1 is the base plan that applies to all participants, providing context about Cook
County and the natural hazards that exist here.
• Volume 2 consists of mitigation action items from each participating municipality and
Cook County. This volume describes the mitigation actions that will reduce the impacts of
natural hazards particular to each community and the County.
If you have any questions, please don't hesitate to contact Kim Nowicki at
Kimtierly.Nowicki@cookcountyil. ov.
VILLAGE OF LEMONT
RESOLUTION NO.
A RESOLUTION APPROVING THE ADOPTION OF THE 2024 UPDATE OF THE
COOK COUNTY MULTI -JURISDICTIONAL HAZARD MITIGATION PLAN
ADOPTED BY THE
PRESIDENT AND BOARD OF TRUSTEES
OF THE VILLAGE OF LEMONT
THIS 27TH DAY OF JANUARY 2025
Published in pamphlet form by
authority of the President and Board of
Trustees of the Village of
Lemont, Counties of Cook, Will and DuPage,
Illinois on this 27th day of January 2025
RESOLUTION NO.
A RESOLUTION APPROVING THE ADOPTION OF THE 2024 UPDATE OF THE
COOK COUNTY MULTI -JURISDICTIONAL HAZARD MITIGATION PLAN
WHEREAS, the Village of Lemont ("Village") is an Illinois Municipal Corporation
pursuant to the Illinois Constitution of 1970 and the Statutes of the State of Illinois; and
WHEREAS, the Village is desirous to adopt the 2024 update of the Cook County Multi -
Jurisdictional Hazard Mitigation Plan as further outlined on the plan attached as Exhibit A
("plan"); and;
WHEREAS, the Mayor and Board of Trustees find that it is in the best interests of the
Village to authorize the Adoption of the 2024 update of the Cook County Multi -Jurisdictional
Hazard Mitigation Plan;
BE IT RESOLVED by the Village President and Board of Trustees of the Village of
Lemont, Counties of Cook, Will and DuPage, Illinois, as follows:
SECTION ONE: The Mayor and Board of Trustees of the Village of Lemont hereby
accepts, approves and adopts in its entirety, Volume 1, the Countywide Mitigation Actions in
Volume 2; and the Village of Lemont Jurisdictional Annex of Volume 2 of the 2024 Cook County
Multi -Jurisdictional Hazard Mitigation Plan.
SECTION TWO: The Mayor and Board of Trustees of the Village of Lemont will
continue to participate in the updating and revision of the 2024 Plan with another plan review and
revision to occur within a five-year cycle, and designated staff will provide annual progress reports
on the status of implementation of the 2024 Plan to the president of the Village council.
SECTION THREE: This Resolution shall be in full force and effect from and after its
passage, approval and publication in pamphlet form as provided by law.
APPROVED BY THE PRESIDENT AND BOARD OF TRUSTEES OF THE
VILLAGE OF LEMONT, COUNTIES OF COOK, WILL AND DUPAGE, ILLINOIS on
this 27TH DAY OF JANUARY 2025.
PRESIDENT AND VILLAGE BOARD MEMBERS:
AYES: NAYS: ABSENT: ABSTAIN
Janelle Kittridge ✓r
Dave Maher I/
Ken McClafferty
Kevin Shaughnessy
Rick Sniegowski
Ron Stapleton
J011N EGOFSKE, Village President
AEST:
CHA + NE M. SM LLEN, Village Clerk
mm
3
EXHIBIT A
2024 UPDATE OF THE COOK COUNTY MULTI -JURISDICTIONAL HAZARD
MITIGATION PLAN AND ADDENDUMS (2024 EXECUTIVE SUMMARY AND 2024
EXECUTIVE OVERVIEW)