Degrees of Change: Sponge Cities and Pocket Prairies. April 26, 2019, Part 1

Climate change is happening—now we need to deal with it. Degrees of Change, a new series of hour-long radio specials from Science Friday, explores the problem of climate change and how we as a planet are adapting to it. In this first chapter, SciFri looks at how climate change affects water systems. This year, there were record downpours in the American Midwest that washed out levees and caused catastrophic flooding. Meanwhile, California is recovering from a seven year-long drought that led to water shortages across the state.

Cities are starting to rethink their water futures and how they can make their communities more resilient. Here are two examples of how cities around the world are adapting to their climate change future.

The ‘Sponge Cities’ Of China

In China, more people are leaving the countryside and moving into big cities. Shenzhen in the south has gone from a city of 50,000 people to over 13 million in just three decades. This rapid urbanization has led to more construction, more concrete, and entire landscapes that have been paved over. Mix that with stronger storms driven to climate change, and the stage is set for future water disasters.

To combat this, the Chinese government started the “Sponge Cities” program in 2014, which calls for cities to soak up and reuse 70% of their rainwater.

Journalist Erica Gies and Chris Zevenbergen, flood risk management expert, talks about the pedestrian bridges, green roofs and terraced urban landscapes that architects and engineers are designing to build resiliency and what needs to be done to expand these ideas to the rest of the country.

The ‘Pocket Prairies’ Of Houston

In 2017, Hurricane Harvey hit some areas of Houston with nearly four feet of rain, causing widespread flooding throughout the city. As the city rebuilds, “pocket prairies” are among the tools being used to manage future flooding. These patches of native prairie grass can be planted anywhere—in front yards, traffic medians, parking lots, vacant lots, and between city buildings—and high quality prairie habitat can hold up to nine inches of rainwater during a storm, reducing the likelihood of catastrophic floods.

“At a neighborhood level, they can manage the ‘flash’ part of ‘flash floods,’” says Laura Huffman, Texas regional director of The Nature Conservancy. Plus, pocket prairies provide additional benefits, she says. As rainwater seeps into soil, it pre-treats chemicals in the rain, helping to keep them out of the water supply. In this conversation, Gies and Huffman explain the benefits of pocket prairies and other green infrastructure.

The Climate Effects Of A Heated Campaign Season

The Democratic presidential primary field is vast—where do the candidates stand on climate issues? Scott Waldman, White House reporter with Climatewire and E&E News, joins Ira to talk about how 2020 presidential campaigns are addressing climate change, plus other climate-related stories of the week—from Facebook's plans to fact-check hot button issues like climate change to a new study that attempts to put a price tag on the effects of Arctic melting.