The Canada Revenue Agency’s ability to deliver vast sums of money without hiccups will ultimately determine whether millions of Canadians affected by the COVID-19 pandemic can pay rent and buy groceries in the weeks ahead.

The federal tax agency has become the crucial linkage between Canadians and tens of billions of dollars in federal relief, including the new $2,000 Canada Emergency Response Benefit (CERB) for many workers who are now unemployed.

While new programs often take months to ready, the benefit’s web portal is set to start receiving applications in just six days, and any delay or technical glitch could put many Canadians in financial peril. Four million applications are reportedly expected online and through an automated telephone system.

The short timeline to build the digital infrastructure and handle millions of applications in a short burst is an entirely new challenge for the agency, said Andrew Treusch, CRA’s commissioner from 2012 to 2016.

“Four million plus (claims), with a couple of weeks head start — that’s unprecedented,” he said. “Having said that, if there’s any apparatus in the Government of Canada to do that, it would be the CRA.”

Treusch said the CRA has among the best IT capability and in-house digital expertise across the entire federal public service, making it well-equipped to administer a large volume of claims.

That may allow Ottawa to meet its target in getting money to Canadians within 10 days of a submitted claim. To prepare, the agency is asking Canadians to update their CRA account and direct deposit information ahead of the portal’s debut.

But to add to the agency’s workload, millions of Canadians file their annual tax returns around this time, although Ottawa has pushed back the deadline until June. As well, the GST credit and Canada Child Benefit will be topped up next month.

The CRA will also soon administer the 75-per-cent wage subsidy program for businesses to keep workers on their payrolls. More details on the program are coming Wednesday.

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The agency’s website currently says Canadians contacting the agency may experience “longer than usual wait times due to fewer available agents.” The CRA is now asking clients to limit their calls to inquiries regarding 2019 income tax and benefit returns, benefits, or issues related to setting up online accounts.

The National Post reported last week that call centres were operating at “reduced capacity.”

Marc Brière, national president of the 26,000-member Union of Taxation Employees, said almost 600 “non-critical” employees have so far volunteered to man telephone lines ahead of the CERB rollout, an initiative done in collaboration with the agency itself.

These volunteers would be able to answer simple questions on the benefit, easing the workload of professional call agents already working at full demand, he said.

Etienne Biram, a spokesperson for the CRA, did not offer new details on the CERB’s progress but said the agency “is confident that its systems are well positioned and that it can administer the CERB effectively and efficiently.” He added that many employees are still working while more remote working equipment continues to become available for staff.

“The CRA’s top priority right now is to ensure the benefit application process is simple and clear, and that benefit payments will get into the hands of Canadians as quickly as possible. The CRA already issues tens of millions of benefit payments year round,” Biram said.

The agency’s role in the federal response increased after it became clear the employment insurance system could not effectively handle the almost one million applications received during the week of March 16.

Employment Minister Carla Qualtrough said at a news conference Thursday that the CRA is better equipped to handle a large volume of claims compared to EI, which is administered through Service Canada within Employment and Social Development Canada (ESDC).

“They have a massive capacity to administer bulk applications very streamlined and confidently, and that’s the security we were looking for and that’s why it will be delivered through CRA,” she said.

ESDC is sharing responsibilities with the CRA in administering the CERB, while the agency is collaborating with Shared Services Canada and government vendors to ensure digital infrastructure can support demand, according to Biram.

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Brière said union members have also put aside a longstanding labour dispute to work more during the crisis. Members have been without a collective agreement since October 2016 and a strike vote was held as recently as February.

He said the crisis is an opportunity for its workers “to step up to the plate and deliver an unprecedented response.”

“I would categorize this as probably the biggest challenge in our history,” Brière said. “But our members have proven before that they can deliver when necessary.”

He added that while thousands of CRA employees are working from home, there is no indication it will hamper the CERB rollout. Meanwhile, testing on the portal is underway.

Treusch, who expects the CRA to successfully meet the April 6 deadline, said the agency has experience working on tight turnarounds from measures announced in past budgets or throne speeches.

But for now, the government should offer more information to the public explaining the benefit and clarify details on who is eligible, he said. Doing so would also help to lower call centre volumes.

“I think they’ve (the government) given this to the very best place,” Treusch said of his former agency. “But it is a daunting challenge.”

Update: Comment from the CRA has been included since the story was first published.