1.5.1 Number of deaths, missing persons and directly affected persons attributed to disasters per 100,000 population
In order to localize this indicator, our team’s assessment included documentation of the percentage of housing units lacking complete plumbing and telephone services, the percentage of the population with reported access to clean water, and the percentage of the population with a broadband internet subscription. A complete snapshot of these parameters is available for download within our metadata.
QUICK LINKS:
Climate Change and Urban Infrastructure
HAZARDOUS WEATHER
Through the science of extreme event attribution, researchers have established a significant link between human-caused climate change and extreme weather events, defined as incidents ranking above a certain threshold near the upper or lower ends of historical measurements. Metropolitan Washington Council of Governments’ 2019 Climate Risk and Vulnerability Assessment identified extreme heat days, drought, flooding, lightning/thunderstorms, extreme winter conditions, and coastal flooding as potential climate hazards facing the area, with the highest risk associated with flooding.
Flooding poses a number of challenges to both infrastructure and people, particularly in urban environments. Flooding can inundate electric substations, Metrorail lines and stations, bridges and tunnels, drinking water infrastructure, and water collection systems. DC has historically been highly susceptible to flooding due to its geography at the junction of two tidal rivers and a vulnerable wastewater collection system prone to Combined Sewer Overflows. A DC Vulnerability and Risk Assessment found that community resources such as schools, medical services, and human services were most vulnerable to flooding in Wards 6, 7, and 8.
Nowhere is this catastrophic convergence of geography and vulnerability more apparent than in Ellicott City. Located in Howard County, Maryland, in the valley of the Patapsco River, the historic buildings and small businesses populating Main Street make the city a popular tourist destination. In recent years Ellicott City has experienced two devastating floods. While the city has experienced 18 major floods since 1789, most of these floods were “bottom-up” floods or flooding caused by the Patapsco River overflowing. In contrast, the more recent 1 in 1000 year floods in 2016 and 2018 that swept down historic Main Street were “top-down” floods, meaning extreme rain events carried water down from the top of the watershed. The 2016 flood claimed two lives, caused $22 million in damages and $42 million in lost economic activity. The following 2018 flood claimed another life and demolished repairs from the preceding catastrophe. The extremity of the events was attributed to both climate change and upstream development that exchanged forested slopes for impervious surfaces. The devastation incurred was compounded by the fact that more than 75 percent of the businesses in the historic area did not have flood insurance because they either could not afford it or because they did not understand the complicated insurance options, did not understand the National Flood Insurance Program (NFIP), or did not qualify for NFIP as a small business.
CLIMATE CHANGE AND URBAN INFRASTRUCTURE
Climate change poses a diverse set of challenges to the critical infrastructure systems in urban areas that are essential for the function and safety of society, such as energy infrastructure, water infrastructure, transportation systems, and telecommunications, all of which require continuous investment and maintenance. However, infrastructure has exceeded its intended life in cities across the country and become exceedingly fragile, especially when compounded with climate change risks. Additionally, infrastructure systems are interdependent, which can cause cascading effects through systems in times of shock. For example, the loss of electric power can impact communication systems and disablepumping, processing, and treating water supply and wastewater.
Water infrastructure is also vulnerable to shocks from both flooding and drought. To wastewater systems, droughts can result in blocked or even bursting sewage systems without adequate flow to process human waste, whereas flooding can cause overflow. The chronic stress of increased rainfall can cause similar effects. For example, in Richmond, Virginia, 15,500 cubic meters of untreated sewage were dischargedinto the James River after rainfall was 50 percent above average in 2018.
The vulnerability of people in relation to climate change’s impact on urban infrastructure will be multiplied by pre-existing social vulnerabilities such as socioeconomic status, age, gender, race, and disability that affect adaptive capacity. The elderly are especially sensitive to heat, creating dire consequences without sufficient cooling in the event of a power outage. The power grid itself is also vulnerable to extreme heat and average rising temperatures as higher temperatures increase energy demand, lower the efficiency and lifetime of components, and can even force power plants offline. For populations relying on at-home electricity-dependent medical equipment, power outages can become life-threatening within hours.
In their 2030 Climate and Energy Action Plan released in November of 2020, the Metropolitan Washington Council of Governments identified infrastructure conditions and maintenance as the factor with the highest degree of challenge for adaptive capacity citing the high risk from extreme heat and flooding. More broadly, a significant challenge for metropolitan areas in planning for adaptive capacity and resilience, such as the DMV, is coordination across jurisdictional boundaries. The need for collaboration across the 24 local jurisdictions comprising the metro area is highlighted in the Action Plan as necessary for capacity building, expertise sharing, and developing a common framework for resilience planning.