The San Ysidro border crossing hasn't shut down in 30 years - until earlier this week. On Wednesday, a construction canopy collapsed, 11 people got hurt.
Northbound traffic started flowing early Thursday morning, but border officials don't know when all 24 northbound lanes will open.
The decision to shut down traffic at the world's busiest land port has some thinking there needs to be a better contingency plan in place for these types of situations.
"How could a 50-foot scaffolding shut down 24 lanes?" asked Jason Wells, executive director of the San Ysidro Chamber of Commerce.
Wells says border leaders are still crunching numbers, but the economic impact the closure will have on the region will likely run into the millions.
About 50,000 cars and trucks cross here on an average day. On Wednesday, Wells said, San Ysidro was a ghost town. That's why he says border officials need to be better prepared.
"The plan has been 'oh we can go through Otay Mesa,' well that doesn't work when you have students and business people trying to cross you can't just go somewhere else," said Wells.
But Jackie Wasiluk with U.S. Customs and Border Protection says the first order of business was security.
"Safety is paramount so out of an abundance of caution we shut down all traffic at the port of entry," she said.
Wasiluk says authorities reopened lanes only after they knew the area was safe.
The cause of the accident is still under investigation.
