Union bosses are warning that "thousands" of public service sector employees will be receiving notices advising them that their jobs will be "affected" as a result of the government's spending cuts this week, just as members of one of Canada's largest unions meet for a national convention in Ottawa beginning Sunday.

Speaking to CBC News from the Ottawa Convention Centre, Larry Rousseau, the Public Service Alliance of Canada's regional executive vice president representing the National Capital Region, said the union was advised that "thousands" of work force adjustment (WFA) notices would be going out to public service employees beginning Monday.

The impact of those notices will be "considerable," according to the Canadian Association of Professional Employees (CAPE), which represents approximately 14,000 economists, statisticians, analysts, research assistants, translators, interpreters, terminologists and social science services workers.

In an interview from Quebec City with CBC News on Sunday, CAPE president Claude Poirier said he is bracing for "anywhere from 4,000 to 6,000 employees" to receive WFA notices at Statistics Canada and Human Resources and Skills Development Canada alone.

Receiving a WFA notice doesn’t necessarily mean that a person will be unemployed, but a process is triggered in which employees are either offered other positions for which they are qualified, given the option of applying for other jobs within six months or taking severance and leaving the public service altogether.

Public service sector employees in at least six federal departments — Aboriginal Affairs and Northern Development, Library and Archives Canada, Transport Canada, Foreign Affairs and International Trade, Statistics Canada, Human Resources and Skills Development Canada — will receive such notices this week. The unions representing them received the required 48-hours notice of impending job cuts from the government on Friday.

CBC News reported Friday, that diplomats and embassy staff Foreign Affairs and International Trade are bracing for federal cuts, with at least four Canadian trade consulates in the United States and seven of the 18 international trade offices in Canadian cities and towns across the country seeing their doors shut next week.

Productivity down as cuts loom

In an interview from the Ottawa Convention Centre on Sunday, PSAC national president John Gordon said "a lot of people that are coming to this convention are going to be people who have received notices from the departments, or they're the people on the front lines who are getting the members 'affected' coming to them."

"There's a lot of angst out there. People, quite frankly, are very afraid."

According to Gordon there's no doubt that the productivity level is going down in all departments.

"You can't tell people they're not going to have a job and expect everything to run smoothly," he said.

More than 10,000 public service employees received notices telling them their jobs are "affected" since the federal budget was announced last month. Of that, Gordon said roughly 8,000 are PSAC members.

PSAC will be in a position to give further details once public service employees have learned of the WFA notices first-hand.

More than 500 delegates representing PSAC's 172,000 members are meeting for the union's National Triennial Convention from April 29 to May 4 in Ottawa.

At the top of the agenda will be this third round of notices and how to help members cope. Delegates will also elect a new national vice-president and national president to replace Gordon, whose six-year term comes to an end this week.

Earlier this week, budget watchdog Kevin Page said balancing the books by 2015-16 will come at a cost of slow growth, delayed economic recovery and 108,000 jobs lost in the public and private sector.

In its March budget, the federal government said 19,200 public service sector positions would be cut over the next three years in an effort to find government savings of $5.2 billion during that time.

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