As President Trump and congressional leaders get to work on an infrastructure package to fix the country's roads and bridges, some are already crumbling -- literally.

The Gerald Desmond Bridge opened in 1968 and connects two of the busiest ports in the country with the California city of Long Beach and the interstate. Supporting 35,000 truck trips per day, the aging bridge helps to transport 15 percent of all U.S. containerized imports.

But it's nearing the end of its useful life. Nets have been installed beneath to catch the chunks of concrete that fall into the channel below.

Later this year, it's set to be replaced, at a cost of $1.5 billion. The new, taller bridge will feature twin 50-story towers and will allow passage of much larger ships. Featuring bike and pedestrian paths plus observation decks, it will be more pedestrian-friendly than the bridge it replaces.

The new structure has also been designed to withstand earthquakes by purposefully breaking in ways that can quickly be repaired. Seventy-five seismic sensors will measure activity from the several nearby faults.

Built to stand 100 years, the new bridge will last twice as long as the one it replaces.