The union that represents striking Region of Waterloo workers says it has offered a "fair" proposal to the region for a new contract, but that it's been rejected.

The Canadian Union of Public Employees (CUPE) local 1656 said it met with the region over the weekend and the two sides "exchanged proposals."

Workers walked off the job on March 4. The union says it's calling for higher wages to keep up with the rising cost of living. Those represented by the union include people who work in departments including water, airport services, regional road maintenance, landfill services and emergency vehicle maintenance.

The union says the region promised, then went back on an offer for workers in contract negotiations.

Local union president Phil Dominas said in a release that the deal they proposed on the weekend would have seen striking workers return to their jobs this week.

Instead, it was rejected and Dominas says the region "continues to move the goalposts on us."

"We went in on the weekend thinking we would be able to negotiate a fair deal, but the employer continues to backtrack on commitments they made to us in negotiations and demand that we settle for less," Dominas said.

The Region of Waterloo says on its website that it "remains available to negotiate as soon as possible to reach an agreement that is competitive for CUPE Local 1656 staff and affordable for residents."

The region has said it has a contingency plan in place to ensure services are maintained during the strike. Mathieu Goetzke, the acting CAO with the Region of Waterloo, told CBC News the work normally done by about 240 outside workers is now being performed by about half that number of people.

Since the strike started, management and support staff have prioritized services that include removing snow from the airport runway. Flights are running on schedule but travellers have been told to arrive early.

On the roads, the region is also working on fixing potholes that need to be repaired across the region.

Where waste collection is concerned, the curbside collection continues as normal but the waste landfill sites in Waterloo and Cambridge remain closed.

Goetzke also noted water testing is highly regulated.

"Operators require licenses and certifications. But as part of our management and management support staff, we have all the people who have the appropriate licenses and certifications. And so they're running the system right now," Goetzke said.

The region had to submit its contingency plan to the Ministry of Environment, Conservation and Parks.