CALGARY -- A new program introduced last month to take care of paying government workers isn't doing the job it should and employees are now short money, an Alberta union says.

The software, called 1GX, was installed in December and the Alberta Union of Public Employees (AUPE) says it's "causing chaos."

It says the issues are reminiscent of Ottawa's Phoenix payroll system, which affected thousands of workers with the federal government.

"I know the UCP government likes to blame the federal government for all its woes, but this time it seems to have decided to mimic the problems created by Ottawa’s Phoenix payroll system," said Susan Slade, AUPE vice-president in a statement.

She says some members only received about 40 per cent of the wages they were supposed to while others are missing shift and weekend differentials. There are also problems with not enough tax being taken off each time.

"There are a multitude of issues that we are hearing," Slade says.

The union accuses the government of rolling out 1GX before it was ready and before it could properly train workers and managers to use it. The software appears not to be able to handle the work it was designed for, Slade says.

"It is clearly incapable of handling the complexity of a large, complex workforce with members working a vast variety of different jobs and different shifts," Slade says. "There is an expectation, as an employer, that when you hire somebody they are going to do a job for you. The expectation of the employee is that you're actually going to be paid for the work that you're doing in a timely fashion."

The union, which represents 20,000 workers who are directly employed by the government, estimates that as a result of 1GX's issues, as many as 5,000 employees may be owed money or have experienced problems.

The affected workers are correctional workers, group home staff members and Fish and Wildlife employees.

The union is working with the Alberta government to resolve the problem before it becomes widespread, but says it has been around for a while.

An email sent from management on Jan. 8 and acquired by the AUPE said it was aware of issues with the system but gave no estimated time on when it would be fixed.

Slade calls the error and the government's inaction "a slap in the face" to public-sector employees.

"They should not have to fight to get the money they are owed. They have bills to pay and need the money," she says.

"It’s bad enough that these dedicated workers have to go to work every day enduring attacks from the government, facing thousands of job losses and attempts to slash their wages, but to not pay them for their work is insulting."

'SMALL PERCENTAGE' OF WORKERS UNDERPAID

The Alberta government, in a response to CTV News' inquiry about the issue, says only a small number of government employees were affected when the switch to the new payroll system was made last month.

According to information from Service Alberta, the ministry has received approximately 531 reports of payroll issues with employees.

Officials say they are working on resolving all the concerns brought up by its workers and the union as soon as possible.

"We understand the concerns that staff have on this," said Tricia Velthuizen, press secretary to Service Alberta Minister Nate Glubish, in an email to CTV News. "(We) are confident that the issues experienced will not be a long-term concern."

All outstanding payments are being made to all staff impacted by the issue, Velthuizen says, and all affected staff should expect to be paid appropriately.

"They have been contacted by their managers and are working together with Service Alberta to resolve the issue," she says. "Staff who believe they’ve been affected but have not been contacted directly can call the Government of Alberta Service Desk for support."

The AUPE says it would also like to speak with any of its members who have experienced their own payroll problems as a result of 1GX so that they can keep track of how widespread the issue is.