KITCHENER -- Freezing rain and snow made for messy roads in Waterloo Region for drivers and LRT riders.

The icy conditions suspended service over the weekend. The LRT is up and running again, but many are wondering how this happened at all.

Service was halted between the Uptown Waterloo stop and Conestoga Mall for much of the day Sunday.

Keolis, the company that oversees the Ion and its service, says that Sunday morning's freezing rain caused ice accumulation on the overhead wires on an isolated area.

"We were prepared for it and really it was a case of the intensity of the freezing rain just at that moment," explains general manager Ian Cushion.

"And the fact that trains have to stop at the stations and they can't keep running means that there's just those occasions where the ice just has a chance to build up and then we need to be able to get moving again."

Riders were asked to take buses instead, but it the region says that came as no additional cost.

"The bus shuttle service provided yesterday for the Ion service disruption was provided with no direct additional costs. It was conducted using three spare buses with three operators," manager of communications Sandy Roberts says.

"This shuttle was operated as part of our planned contingency of vehicles and operators that are used to respond to and supplement any service issues as needed on a daily basis."

Trains did make stops at Waterloo Public Square, but only to drop off passengers and go south: service on the rest of the line wasn't impacted.

Many passengers were left frustrated, saying that the system should be capable of handling winter weather. Others were more understanding.

"It's a new operation for them. They're testing it out. It's early," one rider told CTV on Monday.

Officials say they were prepared for icy weather, but call Sunday's weather "extreme."

"Freezing rain is an expected weather condition which we have plans in place for, but extreme events such as (Sunday’s) will be examined for further improvements," Cushion says.

Service was back to normal by mid-afternoon on Sunday.