Warm Globally, Flood Locally: Water Crises Loom for U.S. Cities
By Paula Melton
A statistician can have his head in an oven and his feet on ice and say that on average he feels just fine, the old chestnut tells us. Similarly, when we hear about climate change in terms of a 2°C temperature change or a one-meter sea-level rise, that might also sound just fine. Local conditions may give us greater fluctuations in daily temperatures and tides, as they always have.a new report from the Natural Resources Defense Council (NRDC), attempts to bring the catastrophic local implications of global warming—in the form of heat waves, floods, storms, and droughts—home for millions of people living in U.S. cities.
“What we found was that there was really no area or region that was immune to effects from climate change,” Michelle Mehta, a lead author of the report, told EBN. Her hope is that the study, which includes maps showing huge new swaths of flood-prone areas in city streets and other compelling imagery, will “crystallize” the information for the general public. If people look and say, “I know these streets, I know that beach,” she said, “it makes the issue real.”
The comprehensive report aggregates local and regional climate data and scientific studies to profile water-related vulnerabilities in 12 cities: Boston; Chicago; Homer, Alaska; Los Angeles; Miami; New Orleans; New York; Norfolk, Virginia; Phoenix; St. Louis; San Francisco; and Seattle. NRDC did not conduct its own studies; the aim, Mehta explained, was to digest “lots of great local scientific research” and make it accessible to the general public as well as local governments. The report also compiles a list of best practices—steps that cities are taking both to decrease their carbon emissions and to prepare for water-related changes.
New York, for example, expects rising sea levels, increased flooding, and more frequent and intense storm events. Its aging, densely packed infrastructure—much of which is currently below sea level—could suffer wide-ranging effects. Subways, power plants, landfills, drinking-water pipes and wastewater treatment pipes will all be vulnerable to flooding and saltwater infiltration—as will many existing buildings. “The southern tip of Manhattan, with expensive real estate within the financial district, is particularly flood-prone,” says the report.
Fortunately, New York has begun taking action to reduce its water-related vulnerabilities—increasing the water-efficiency of existing infrastructure, considering future sea levels when designing new sewer-related projects, and raising electrical equipment at wastewater treatment plants from several meters below sea level to two meters above sea level. Other cities have not even conducted studies, let alone begun making infrastructure improvements, says Mehta, and the report “highlights the need for that to be done in some of these areas that didn’t already have it,” such as St. Louis.
Phoenix is preparing to live with too little water rather than too much. Already an arid metropolis in the grip of a long-term drought and experiencing rising temperatures, the city has begun long-term infrastructure planning to capture more runoff to increase groundwater supplies, and regulatory planning to curtail water demand. Daily water use has decreased more than 20% since 1980, according to the report, and the city anticipates further reductions of up to 10%.
Mehta explained that the report focuses on water because it has such broad effects: a major rise in sea level could have a domino effect on electricity production, agriculture, estuaries, drinking-water aquifers, tourism, fisheries, and other areas vital to local economies. Failing to effectively assess and prepare for the dangers at the municipal level would be devastating to cities and potentially lethal to millions. “Local planning is key,” the report concludes. “But, in the end, only effective implementation of measures to both mitigate and adapt to climate change can ensure that our communities are best prepared to face the coming challenges.”
NRDC has also created anprojecting state-by-state health effects of climate change, including threats posed by air quality, mosquito-borne pathogens, and extreme heat in addition to drought and flood vulnerability.
For more information: