OLD MONROE, Mo. -- Less than an hour north of St. Louis, Missouri Highway 79 has dealt with a range of complications and closures from major flooding in recent years. But even when the nearby Mississippi River is calm, the roadway can't catch a break from the elements -- something illustrated this summer, when punishing heat caused its pavement to buckle, creating a bump that work crews had to fix.
With most of the U.S. exposed to hotter and ever more erratic climate conditions, roads like Highway 79 aren't the only types of infrastructure pushed to their breaking points. As society confronts an increasingly unfamiliar climate, there are signs that the engineered backbones of modern civilization are at risk across the U.S.: Rising seas spoiling water supplies. Power plants idled because water from ponds and rivers, used to cool generators, is no longer as chilly as it used to be. Dams threatened by torrential rains and runoff.
New extremes are testing roads, bridges, dams and utilities to unprecedented degrees, even as they age beyond their intended lifespan.
Climate extremes are becoming more common in the region. St. Louis has seen record-high temperatures with greater frequency in recent years, according the National Weather Service -- including a peak of 21 days of record-setting warmth in 2012. It's also not getting as cold here, as shown by a rise in the number of "record-warm lows," in which daily low temperatures register as the warmest on record for a given date. Overall, average annual temperatures in the city are now about 3 degrees warmer than they were 80 years ago.
That change -- and unpredictability -- matters for engineers who must take climate into account when designing infrastructure, by anticipating the range of conditions that it must withstand. But now, climate-related bell curves and bedrock assumptions are shifting beneath their feet. The same is true for infrastructure that already exists: Some of what was built decades ago now faces conditions that it wasn't designed to withstand.
Rising seas mean that coastal areas not only confront increased tidal flooding, but also underground saltwater intrusion, forcing some Miami-area municipalities, for example, to shut down or relocate well fields for their municipal freshwater supply. Inland, Toledo, Ohio, briefly saw its water supply choked off in 2014 by Lake Erie's toxic algae blooms -- episodes fueled by agricultural runoff, but made more likely in the hot conditions abetted by climate change.
Elsewhere, aging dams and reservoirs are not designed to accommodate increasingly torrential runoff, as shown by evacuations and the threat of failure at California's Oroville Dam in 2017. And widespread fires in the state, fanned by hotter, drier weather, have led utilities to deliberately cut power to hundreds of thousands of residents, to keep power lines from sparking more.
St. Louis heat
The St. Louis area offers some of its own examples of infrastructure problems amid hot and extreme conditions. Just ask the local road crews.
"If we have long periods of hot days and hot nights, it makes things worse," said Becker. "It's incredibly weather dependent."