Trump's 'great wall': How much will it cost? Who's paying?

U.S. President Donald Trump's promise to erect a wall along the U.S.-Mexico border was a crowd pleaser at his rallies on the campaign trail, its mention prompting cheers for him to "build that wall!"

Now the wall is set to become a reality. Trump, during his first week in office, signed an executive order declaring that the U.S. will build "a contiguous, physical wall or other similarly secure, contiguous, and impassable physical barrier."

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But how realistic is his vision? How much will it cost? And who will pay what he has described as a "great wall?"

Why does Trump want to build the wall?

Trump first called for the building of a wall in October 2014, saying the U.S. needed a better way to stop ISIS at the border.

He later mentioned his plan to build a wall when he announced his candidacy in June 2015.

"I will build a great wall and nobody builds walls better than me, believe me and I'll build them very inexpensively," he said. "I will build a great, great wall on our southern border, and I will make Mexico pay for that wall. Mark my words."

His controversial speech criticized Mexico and suggested that the U.S. had become a "dumping ground" for the wrong kind of people.

"They're sending people that have lots of problems and they're bringing their problems," he said. "They're bringing drugs, they're bringing crime, they're rapists, and some I assume are good people but I speak to border guards and they tell us what we are getting."

Trump told MSNBC in February 2016 that he envisioned building a wall that measured 10 to 12 metres (35 to 40 feet). And don't call it a fence, Trump has responded testily to people who've made the suggestion.

What does the U.S.-Mexico border look like now?

The Secure Fence Act, passed in 2006, funded fencing for a span of 1,126 km (700 miles) along the southern border. At present, fencing has been erected along 1,049 km (652 miles) of the border that runs in total 3,200 km (1,989 miles).The U.S. has spent more than $7 billion on the fencing and barriers that are in place now.

A look at the current Mexico wall

8 years ago

Duration 1:44

CBC's Kim Brunhuber reports from the border near San Diego

Tall steel fences can be found in heavily populated areas and lower corrugated metal barriers have been placed in less dense regions. There are no obstructions in areas where natural barriers, such as the Rio Grande river or high mountain ranges, exist.

How much will it cost?

Trump estimated that the wall will cost about $8 billion US, a figure many suggest might be too low.

A 2016 report from Bernstein, an investment research firm, suggests the cost would likely be much higher, ringing in somewhere between $15-$25 billion.

The Bernstein report cited the Government Accountability Office, which in 2009 reported that one mile of fencing (1.6 km) along the border cost between $2.8 million and $3.9 million to install. The report also noted that this calculation applied to the "easiest" stretches of land.

Critics have also questioned if Trump's estimate also takes maintenance of the wall into account.

Will Mexico actually pay for the wall?

Former Mexican president Vicente Fox revived a Twitter spat with Trump after the executive order was issued. Fox sent a candid message to the new White House press secretary.

Trump responded and suggested that if Mexican President Enrique Pena Nieto disliked his administration's stance, he should cancel a scheduled visit to the U.S.

Nieto, who has repeatedly said Mexico will not pay for the wall, said he would not attend meetings at the White House as planned. He also noted that he was still willing to work with the U.S.

Trump himself has been ambiguous, saying Mexico will pay for the wall and then modifying his stance slightly saying Mexico will pay them later.

Sean Spicer, White House press secretary, suggested the U.S. might fund construction of the wall by introducing a 20 per cent border tax applied to imports from Mexico. He later clarified that the tax was just one option the Trump administration was exploring.

Given that the Secure Fence Act has almost fulfilled its mandate of erecting 1,126 km of fencing, Trump would need the support of Congress to continue building along the border.

What other obstacles exist?

Trump's team has reportedly had meetings with the army and Interior Department to assess environmental obstacles to building the wall, according to CNN. Critics suggest a wall might threaten the movement of species in the Rio Grande. The Bernstein report also notes that construction in some areas might be difficult, given the territory crosses several floodplains.

What about Canada?

Trump rejected the idea of building a wall along the Canada-U.S. border last February in a debate televised on Telemundo. He said erecting such border would be too costly and without cause.

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"It would be very, very hard to do and it is not our biggest problem," he said. "I don't care what anyone says. It is not our big problem."

Border wall a 'horrible symbol of ignorance' says former Mexican congressman

8 years ago

Duration 8:58

Agustin Barrios Gomez says if Mexico and the U.S. are no longer going to be friends, they can no longer be allies.