Flooding Infrastructure and Climate Change

Over the course of this year, many areas of the United States have experienced severe flooding disasters, including places like Yellowstone, Kentucky, Denver, Death Valley, St. Louis, and Dallas. These areas experienced higher than average prolonged rainfall leading to an inundation of their already weak flood infrastructure, resulting in massive water overflow and significant economic losses. Widespread flooding affects local communities by leading to displacement, damage, and death. With the ongoing climate changes already causing strengthened and more frequent natural disasters, experts agree this flooding is also connected. 

Flooding does not only occur in these large regions because of the excess rain, although that is a significant factor. Many other factors are involved in severe flooding events, and the root of the problem is the predominant lack of adequate flooding infrastructure. Most urban areas use a combination of gutters, storm drains, and underground sewers to remove excess water from street surfaces and redirect it out of the city. These systems work well when there are periodic rain storms, characteristic of the region. However, their systems begin to malfunction when extensive amounts of precipitation inundate the region over a short period. Large influxes of water into the drainage infrastructure can rapidly overwhelm sewers resulting in backflow of water, pooling in large areas of these urban areas. The water can quickly become fast-moving water sources, wreaking havoc on communities and urban centers. 

Effects of flooding from past events like the 2005 Hurricane Katrina can still be seen across Louisiana today. Floods have enormous social consequences for impacted communities and individuals by threatening loss of human life, destroying property, damaging crops, deteriorating health, and leading to increased water-borne illnesses. The long-term effects of these floods can also disrupt clean water access, wastewater management, electricity, transportation, communication, and the loss of countless livelihoods. 

Another major factor affecting the outcome of these flooding events in urban areas is the lack of natural land that would otherwise effectively absorb and redirect excess water into surrounding areas. Most cities have surface areas encased in asphalt and concrete, preventing water from seeping into ground soil below. Impermeable surfaces in large cities increase their susceptibility to flooding when there are large influxes of rain, often making flooding worse.

Many technological and wealthy countries have been investing significantly in flood forecasting and preparation, inadvertently leaving their cities without many of the critical flood infrastructure systems that would protect them from these events. The resulting lack of development has led to many instances of significant loss of life regardless of the ample warnings because the areas were not physically able to manage such large influxes of water. 

The unfortunate reality faced by many areas across the United States is that these flood prevention infrastructures, like dams, reservoirs, and storm drains, were all designed decades ago and are completely outdated. Installed systems have failed to adequately handle the increasing large precipitation events over the last decade. 

New research into natural sources of flood protection found in flood plains, forests, and wetlands discovered that protecting and restoring these threatened regions could effectively protect nearby cities from a large quantity of flooding. These efforts, updating outdated infrastructure, and better allocating development land are all ways to combat future flooding events. 

IPCC Climate Change Report Finds That Major Climate Changes Are Inevitable and Irreversible

The United Nations formed the Intergovernmental Panel on Climate Change (IPCC) to inform national governments about the science and potential impacts of climate change. Humans have heated the planet by roughly 1.1°C since the 19th century, mainly from burning coal, oil, and gas for energy. 

The consequences of global warming can be seen this summer alone, with heatwaves across the US and Canada, floods devastating Germany and China, and wildfires are raging out of control across the world. Unless immediate, rapid, and large-scale action is taken to reduce emissions, the report says, the average global temperature is likely to reach or cross the 1.5°C warming threshold within 20 years. 

Some key points from the IPCC report:

  • Global surface temperature was 1.09C higher in the decade between 2011-2020 than between 1850-1900.

  • The past five years have been the hottest on record since 1850

  • The recent rate of sea level rise has nearly tripled compared with 1901-1971

  • Human influence is "very likely" (90%) the main driver of the global retreat of glaciers since the 1990s and the decrease in Arctic sea-ice

  • It is "virtually certain" that hot extremes including heat waves have become more frequent and more intense since the 1950s, while cold events have become less frequent and less severe

While this report is more clear and confident about the downsides to warming, the scientists are more hopeful that if we can cut global emissions in half by 2030 and reach net zero by the middle of this century, we can halt and possibly reverse the rise in temperatures. 

Reaching net-zero involves reducing greenhouse gas emissions as much as possible using clean technology, then burying any remaining releases using carbon capture and storage or absorbing them by planting trees.

According to a draft of an upcoming IPCC scientific report, some lifestyle changes could also cut emissions twice the size of Brazil’s current emissions by 2030. Changes include heating and cooling set-point adjustments, reducing appliance use, shifting to human-centered mobility and public transit, reduced air travel, and improved recycling. The draft IPCC found that individual behavior change in isolation cannot reduce greenhouse gas emissions significantly, but individuals can contribute to overcoming barriers and enable climate change mitigations. 

The full second report, set to be released in 2022, will detail how climate change might affect human society, such as coastal cities, farms, or health care systems. A third report, also expected next year, will explore more fully strategies to reduce greenhouse gas emissions and halt global warming.