A shortage of 80,000 truck drivers is wreaking havoc on the supply chain—and it’s about to get worse

America needs to keep on trucking: The $791.7 billion industry hauls 72.5% of all freight transported in the United States and employs about 6% of all full-time workers. But an aging workforce combined with the recent surge in labor shortages could spell disaster for the vital industry.  

The ongoing truck driver shortage is now estimated at 80,000, up from 61,000 just three years ago. A new study by Bob Costello, chief economist for the American Trucking Associations (ATA), estimates that the industry will have to recruit 1 million new drivers within the next nine years to replace retiring drivers. 

Many factors contribute to a lack of drivers, said Costello, including age demographics, trouble recruiting and retaining female drivers, the ongoing COVID-19 pandemic, drug testing, age restrictions (commercial drivers must be 21), time away from home, pay, and infrastructure issues. “Because there is no single cause of the driver shortage, that means there is no single solution,” wrote Costello. “The solution to the driver shortage will most certainly require increased pay, regulatory changes and modifications to shippers’, receivers’ and carriers’ business practices to improve conditions for drivers.” 

President Joe Biden’s COVID-19 vaccine mandate, expected to go into effect by the end of November, could further decimate the already ailing industry. The ATA met with White House officials this week to warn them that many drivers would likely leave the industry rather than get vaccinated or take weekly tests. They estimate that about 37% of drivers could leave or retire owing to the mandate.

“Now placing vaccination mandates on employers, which in turn force employees to be vaccinated, will create a workforce crisis for our industry and the communities, families, and businesses we serve,” Chris Spear, ATA president and CEO, wrote in a letter to the Office of Management and Budget last week.

Signs of the declining industry are already being seen around supply chain issues. Earlier this month, President Joe Biden ordered Southern California ports to stay open all night in order to ease supply chain kinks. But new data shows that a lack of truckers is causing the slowdown. Shipping giant Maersk recently reported that half its 2,000 appointments for truckers at the Port of Long Beach were unused on Friday. 

“This level of operations is not an overnight, simple solution to implement — and does not solve the broader supply chain capacity challenges and shortage of workers in trucking, warehouse, and supply chain jobs,” Narin Phol, regional managing director of Maersk North America, said at an industry conference in South Carolina on Monday. 

Truckers say that the backup is also due to a lack of storage space: They are struggling to pick up new shipping containers because they’re required to hold on to empty, old containers owing to long wait times (which are often unpaid for drivers) and restrictions on returns at ports, Matt Schrap, CEO of Harbor Trucking Association, a coalition of carriers that serves the ports of California, told Bloomberg.

Things will only get worse, Costello warned. 

“I think the supply chain problems of today are a glimpse into the future if we don’t fix this. At some point, what will happen is you will go to the grocery store, the driver shortage will get so bad, instead of seeing seven kinds of apples, you will see three,” he said.  

It’s not just truckers who need to worry about this problem, he added, all hands need to be on deck. 

“This is a warning to shippers, the supply chain, everything. When you look at demographics, and [if] nothing changes, the driver shortage could reach 160,000 in the next 10 years,” Costello said.

But there are solutions that could be easily implemented. One easy answer to these problems rests in President Biden’s Build Back Better infrastructure plan. “Things like infrastructure affects the driver shortage,” Costello noted. “When you sit in congested traffic, that affects you.” 

More finance coverage from Fortune:

Subscribe to Fortune Daily to get essential business stories delivered straight to your inbox each morning.