HomeMy WebLinkAboutOshkosh Sustainability Plan - Climate Resiliency DRAFT - 25 July 2025Oshkosh Sustainability Plan 2025
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Chapter: Climate Resiliency
Introduction
Disaster readiness and emergency preparedness have always been critical aspects of local governance.
With the addition of climate change, greater emphasis must be placed on climate resilience. Climate
change poses many expected and unexpected risks that will require our community to adapt to reduce
vulnerability to its negative impacts. Climate resilience involves preparing for extreme events while also
adapting to changing everyday conditions.
It is also important to acknowledge and take responsibility for our community’s contributions to climate
change. Greenhouse gas emissions from burning fossil fuels, agriculture, and deforestation are the
leading causes of climate change and require action to reduce and mitigate our contributions that have
negative impacts. This chapter focuses on strategies to enhance readiness and adaptability to natural
events being amplified by climate change. As our community evolves over time, so will the strategies
needed to respond to the rapidly changing environmental conditions affecting our quality of life.
Past Accomplishments
The City of Oshkosh has already made progress towards sustainability with the following
accomplishments:
• Deployed Emergency Situation Planning for all City staff (i.e. Security and Access Policy)
• Considering life-cycle costs during purchasing decisions to enhance budgeting
• Installing flood-mitigating permeable pavement in several locations
• Partnered with Winnebago County’s Emergency Response Program
• Ongoing assessments of road bridges currently owned by Winnebago County for long-term
maintenance responsibility
Background
Precipitation and Heat. According to the Wisconsin Initiative on Climate Change Impacts (WICCI), the
annual average rainfall for the region surrounding the City of Oshkosh is projected to increase by 10%
between 2000 and 2050. Further, the volume of an average heavy rainfall event (2+ inches in a 24-hour
period) is expected to increase by an even greater amount, interrupted by longer than average periods
of drought. The frequency of such events is expected to increase by about 25% between 2000 and 2050.
Other weather impacts, such as decreased winter snow but increased ice and wintery-mix events, are
future climate patterns that the city must reorient towards. More intense rainfall events mean increased
flash flood risks, runoff pollution into water bodies, and threats to life and property. These trends also
threaten roadway safety and increase strain on Oshkosh’s bridges, roadways, and tunnels. The city’s
storm sewer infrastructure is not built to handle higher volume flows because they were based on the
historical record of smaller storms, thus creating capacity issues. As that infrastructure ages, additional
fortification may be required due to higher velocity flows. Unfortunately, the long-term consequences of
not addressing these risks will potentially cost millions in damages but can be prevented by investing in
future improvements.
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Bridges: Bridges are threatened by extreme heat, causing them to buckle and lose structural integrity; by
extreme rainfall, scouring surfaces and causing corrosion and cracking; by high water levels, causing lift
bridges to be operated more frequently (there are four lift bridges across the Fox River); and by cold
weather, causing them to freeze more quickly than roads. Long-term planning for bridge repairs in the
context of climate change requires shifting expectations from past knowledge to potentially anticipating
shorter replacement periods and adequate maintenance and inspections.
Roads: Roads are threatened by extreme temperatures with more freeze-thaw cycles leading to faster
degradation. More intense rainfall increases wear and tear and flood risks that can wash away surfacing
and damage roadbeds. Emergency service access across the critical road network is also important for
disaster response. Flooding from Lake Winnebago poses concerns about maintaining access and
repairing local roadways. While water levels of the lake can be controlled using dams (which are
managed by the US Army Corps of Engineers), there are limits to how much they can prevent flooding in
urban areas where there are upstream and downstream consequences of water level manipulation.
Keeping roads clear of inundation requires more than flood prevention with dams and flood barriers. A
sustainable approach involves designing infrastructure to capture and store flood waters when overflows
happen.
Tunnels: Tunnels, also called vaults, are buried in front of numerous storefronts, mainly in the downtown
area under sidewalks, and may connect to one another. Flooding and sinkholes can be a persistent and
troubling problem for such locations and may be at increased risk due to more extreme rainfall events.
Strengthening traditionally engineered infrastructure like the bridges, roads, and tunnels is a necessary
adaptation to the increased stresses posed by climate change, but it cannot be solely relied upon to
make the built environment more sustainable. A purely engineered approach, often referred to as “grey
infrastructure” (referring to the concrete, metal, and other man-made materials used to control natural
systems) has negative impacts from channeling water away from the natural environment where it can
replenish soils and into treatment and conveyance systems. Widespread use of a grey-infrastructure
approach can exacerbate flooding, degrade ecosystems, and create a costly uphill battle in fighting
weather events. In addition to grey-infrastructure fortification improvements, supplementing these with
green infrastructure is a useful solution with several associated benefits. Oshkosh is no stranger to green
infrastructure on municipal properties, with increased adoption of permeable pavements and bioswales.
There is an opportunity to continue to install nature-based solutions to help offset the increased risks
posed to infrastructure by extreme weather while also contributing to the City’s goals to increase
vegetative cover across the community and add beautification to walkable areas of the community. As
long as the areas are properly established and maintained, green infrastructure is an integral part of
urban climate resilience strategies.
In addition to increased vulnerability to precipitation, heat is another primary climate risk affecting
communities across Wisconsin. Rising temperatures have implications for USDA Hardiness Zones and the
plants that are recommended for them. Until recently, Oshkosh was in Zone 5a and is now in warmer
Zone 5b. Future predictions state by 2050 Oshkosh will be warmer, with a possible shift to Zone 6a. This
change in hardiness zone has implications for the types of perennial vegetation Oshkosh should select
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for growing in public places and spaces. This may limit the variety
of native vegetation that can thrive in our new climate. New
species threaten to out-compete existing species, and some
existing species may experience decline and need to be
intentionally replaced with hardier varieties due to issues with
pests, diseases, and difficulty adapting to new weather cycles.
Extreme heat events are increasing, too, posing risks to human
health and safety. Historically, the number of days per year over 90
degrees Fahrenheit in Oshkosh was approximately ten days, but
that number is expected to increase to twenty five days by 2050.
The number of nights where the low temperature does not dip
below 70 degrees Fahrenheit has historically been about four, but
that number is expected to increase to sixteen by 2050. This dramatic increase in the number of high
temperature days will have implications for healthcare and emergency services responding to heat-
related illnesses and it will also impact the habitability of certain plants and animals in the region.
Increasing average temperature does not mean that risks from cold temperatures are going away. While
extreme cold is expected to decrease on average, the risk of extreme cold temperatures still persists and
may even be an increased risk in some situations. Warmer average temperatures cause volatility and
instability in the atmosphere and the jet streams that control our weather patterns. A less stable
atmospheric jet stream threatens to continue to dump cold arctic air over the Midwest, causing arctic
blasts and polar vortices. Oshkosh currently has no emergency warming shelters, with the nearest such
facilities located in Fond du Lac and Appleton. These may not be accessible to people during extreme
weather conditions without access to a personal vehicle. These shifts in temperature and weather
patterns not only challenge human infrastructure and health systems but also disrupt the delicate
balance of local ecosystems, altering migration patterns, threatening pollinator populations, and placing
stress on native plant and animal species that may struggle to adapt to the rapidly changing
environment.
Telecommunications. One of the most effective disaster response strategies is to bolster communication
to inform people what is happening, when to expect it, and what actions they should take to be
prepared. With the evolution of telecommunications spanning the internet in addition to traditional
news sources, radio, and non-electronic communication, cities must adapt to ensure they can
communicate with residents with disaster notification systems. Some notification systems, such as the
National Weather Service’s Wireless Emergency Alerts, notify people with cell phones or active radios of
severe weather events. The National Weather Service advises people to check their favorite weather
station, weather radio, the internet, or other trusted sources of information for advice on how to
respond to severe weather, but it is not a guarantee that the chosen source will share the most relevant
information.1
While no single solution for distributing disaster response information exists, there is value in
coordinating systems to ensure as many people as possible are prepared. Many isolated populations
such as older adults, people with disabilities, linguistically isolated populations, and people experiencing
housing insecurity face unique barriers in accessing emergency response services, and they are more
likely to miss or misunderstand notifications about emergencies. Partnerships with organizations that
support these groups can help to increase access to preparedness resources. A local analysis of
vulnerability indicators may also be performed with publicly available data from the US Census Bureau.
Academics from the Whitburn Center
for Governance and Policy Research
at UW-Oshkosh assessed social
vulnerability, community resilience,
and adaptive capacities in East
Central Wisconsin in 2024. The
findings may be useful when deciding
how to approach community
vulnerability.7
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The City of Oshkosh is partnered with the County’s emergency management system and should continue
to promote information about resources made available in the city for specific disasters to be shared by
this system, as well as encouraging residents to sign up for alerts, especially vulnerable populations. The
County’s disaster preparedness planning and hazard mitigation planning efforts are included in the 2022
Winnebago County Hazard Mitigation Plan.2 By having a FEMA-compliant plan in place, communities
become eligible for federal funding to support pre- and post-disaster mitigation projects, which can lead
to long-term savings for taxpayers and improved public safety infrastructure.
Adaptation and Data. The impacts of climate change affect our natural and built environments. The
ability to predict what will happen in the future is based on continued and robust analysis of climate data
and modeling. The predictions must be continuously reoriented to reflect actual events, new
technologies, and emerging data. WICCI provides periodic research updates from the University of
Wisconsin-Madison and the Wisconsin Department of Natural Resources and other experts across the
state to support communities in anticipating and adapting to the impacts of climate change. The latest
2021 Assessment Report: “Wisconsin’s Changing Climate,” outlines the impacts of continued warming,
increased precipitation, and other issues and impacts. The report is anticipated to be updated every ten
years and has shown data reflecting a 17% increase in annual average rainfall since 1950, three degrees
Fahrenheit warming of statewide temperatures, with warmer and wetter trends expected to continue.
Reports such as this, and others shown below, are great resources for understanding the need to adapt
to the ever-changing landscape of climate change.3,4 The Wisconsin Climate Table is another great
resource to monitor and track climate trends with several data tools available, technical assistance,
funding guides, and more.5 The Wisconsin Department of Natural Resources provides information about
the ongoing risks presented by climate change as they are relevant to stakeholders across the state. This
resource is especially relevant to issues with natural resources such as impacts on fishing and wildlife
habitat, key elements of the local tourism and recreational economy. There are also implications
explained to agriculture and forest product industries.6
For additional information on the resources outlined in this chapter, check out:
1 Weather Emergency Alerts | National Weather Service: https://www.weather.gov/wrn/wea
2 2022 Winnebago County Hazard Mitigation Plan:
https://www.co.winnebago.wi.us/sites/default/files/CountyClerk/OtherDocuments/emergency_management_04.0
4.2022_hazard_mitigation_plan_packet_0.pdf
3 Wisconsin Initiative on Climate Change Impacts (WICCI) 2021 Assessment Report: https://wicci.wisc.edu/2021-
assessment-report/full-report/
4 WICCI Trends and Projections: https://wicci.wisc.edu/wisconsin-climate-trends-and-projections/
5 Wisconsin Climate Table Resources: https://wisconsinclimatetable.org/resources/
6 Climate Change Impacts in Wisconsin | Wisconsin Department of Natural Resources (WDNR):
https://dnr.wisconsin.gov/climatechange/impacts
7 Ready or Not?: Assessing Social Vulnerability, Community Resilience, and Adaptive Capacities to Hazards in East
Centeral Wisconsin | UW-Oshkosh Whitburn Center for Governance and Policy Research:
https://www.uwosh.edu/whitburn-center/wp-content/uploads/sites/211/2024/03/Ready_or_Not.pdf
Goal(s):
Emergency preparedness: Strengthen emergency response systems and resources for residents to
prepare for known climate risks to minimize risk to life and property during disaster events.
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Fortification: Assess and retrofit critical infrastructure to promote durability to increased stress from
climate hazards.
Monitoring: Periodically assess climate hazards and risks to inform future resiliency needs.
Recommendations
1. Stormwater. Control stormwater runoff with a combination of green infrastructure, and
engineered solutions to prevent negative impacts of stormwater runoff pollution, erosion, and
urban flooding.
o Lead Responsibility: Public Works
o Time Frame: Ongoing
o Implementation Details:
▪ Continue to install permeable pavements and reduce impervious surfaces on
municipal facilities.
▪ Continue to install rain barrels at City facilities.
▪ Continue to transition passive green spaces in parks, public ways, and other
municipal properties to low/no-mow native prairie grasses that absorb more
stormwater, enhance urban biodiversity, and are more drought tolerant where
turf fields are not needed for outdoor activity. Ensure aggressive provisions for
invasive species removal and maintenance during the first few years of the plant
establishment period, and proper maintenance thereafter. Continue allowing
gardening and “friends of” groups to supplement.
▪ Conduct an impervious surface area analysis of the city limits overlaid with a
green infrastructure inventory, and establish impervious surface reduction goals
within each sub watershed in those limits. The goal should be informed by a
projected model storm event.
▪ Develop a map of flood-prone areas in the city using a combination of observed
flooding reports, flood insurance maps, impervious surface data, and innovative
flood mapping resources such as First Street.7
▪ Promote green roofs and other green infrastructure installations during public
and private developments by sharing stormwater fee reduction incentives and
ensuring those incentives. Ensure stormwater fee structures recognize green
infrastructure solutions for reducing fees.
▪ Consider establishing an “exterior flatwork fee” that
charges properties for permits for exterior
improvements such as paving, decks, earthwork,
and landscaping but offers reimbursements for
flatwork that does not increase impervious surface
above a certain level.
2. Emergency Response. Strengthen disaster preparedness systems to
support residents during emergencies.
o Lead Responsibility: Police and Fire
o Time Frame: Medium Term (3-5 years)
o Implementation Details:
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▪ Continue to partner with Winnebago County’s Emergency Response Program.
Consider coordinating with the Sheriff’s Office for additional emergency
communications.
▪ Establish a hazard notification and response system across multiple
communication modes and languages and accessible to individuals with
disabilities.
▪ Identify and promote evacuation procedures to identify and support individuals
at risk of life-threatening events through disaster preparedness planning,
collaborating with affected groups such as older adults, people with disabilities,
individuals experiencing housing insecurity, and linguistically isolated
populations. Consider attending events where these individuals may sign up for
the County’s emergency alerts.
▪ Identify and establish 1-2 permanent or pop-up safety locations in areas with
high number of vulnerable populations where individuals can receive emergency
assistance and temporary shelter during natural disasters or extreme heat/cold
events. Consider providing backup generators or other micro-power sources at
these locations.
▪ Consider partnering with local organizations to host emergency preparedness
workshops that explain and promote the residential emergency preparedness
strategies in the County’s Residential Guide to Emergency Preparedness.
3. Critical Infrastructure: Establish a network of resilient infrastructure across the city that provides
access to essential services during disaster events.
o Lead Responsibility: Planning Services
o Time Frame: Long Term (5+ years)
o Implementation Details:
▪ Determine the maintenance responsibility of bridges throughout the community
with priority placed on bridges for highways, arterial roadways, major collector
roadways, or bridges providing access to isolated residential areas.
▪ Conduct a study to determine the critical network of resilient infrastructure and
its vulnerability to hazards within the city including roadways, bridges, water
mains, sewer mains, electricity infrastructure, gas lines, and telecommunications
that should be more resilient to natural disasters to ensure first responders,
evacuation routes, and medical facilities are supported. Assess the condition,
lifespan, and ability to withstand projected 100-year storm events and flooding
for each of these facilities.
▪ Accelerate capital improvements for critical infrastructure facilities in disrepair
or infrastructure that is inadequate to withstand natural disasters.
▪ Consider applying for the State Infrastructure Bank (SIB) to finance critical
infrastructure improvements.8
4. Monitoring. Periodically monitor climate data relevant to Oshkosh to identify the need to adapt
sustainability programs for changing hazards and risks.
o Lead Responsibility: Planning Services
o Time Frame: Long (5+ years)
o Implementation Details:
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▪ Utilize data from the Wisconsin Initiative on Climate Change Impacts (WICCI)
and similar resources to stay informed about the most recent climate data when
new reports are released, at least every 5 years.
▪ Identify implications for the Sustainability Plan during future updates based on
new climate data and forecasts.
7 Flood Factor urban flood risk index | First Street: https://firststreet.org/methodology/flood
8 Wisconsin Department of Transportation State Infrastructure Bank (SIB) Program:
https://wisconsindot.gov/Pages/doing-bus/local-gov/astnce-pgms/aid/sib.aspx