GTA motorists will learn more Friday morning about traffic tie-ups on major highways during the G20 summit, and one law enforcement spokesperson isn't sugarcoating the looming disruptions.

"It's going to be very congested, make no mistake about that," Const. Wendy Drummond, a spokesperson for the G8/G20 Integrated Security Unit, said Thursday.

The highway disruptions will come as motorcades transporting representatives from the world’s 20 largest economies. The motorcades will travel to and from Pearson International Airport during the summit period. The G8 leaders meet in Muskoka on June 25 before moving to Toronto for the G20 Summit on June 26 and 27.

The road disruptions will being June 24. "If you don't have to be there (on the roads) and you can make other arrangements," Drummond said.

Motorists on Queen's Quay were already feeling frustrated Thursday, stuck in tie-ups caused by G20 summit security measures. Workers were building the fence right down the middle of the waterfront roadway, something drivers described as a nuisance.

One contractor told CTV News that the fence will wrap around the Westin Harbourfront Castle, but will still allow access to the Toronto Islands ferry docks.

"There will be gates to where they let people into the Harbour Castle and anywhere else," said Fernando Brasil of JTS Inc., a traffic control company.

The security perimeter around the Westin Harbour Castle is isolated from the main inner security zone that surrounds the Metro Toronto Convention Centre, where the leaders will meet.

The fencing is on Queen's Quay between Bay and Yonge Streets. Traffic is to be routed up Harbour Street at York Street and back down Freeland Street to avoid that area.

Motorcades containing dignitaries will be able to drive up to the hotel unimpeded. CTV Toronto's Austin Delaney said there will be an electronic bubble around the motorcades that will prevent people from using their cellphones.

Ordinary people will be inconvenienced.

One motorist said his 15-minute drive will likely turn into 30 to 45 minutes for the next few weeks. A truck driver who works downtown wondered how he was going to cope.

Spec. Const. Emmanuel Sukh said while frustrated, "they (motorists) do understand."

On Wednesday night, a white Mercedes turning out of a condominium building struck a concrete block used to support the fence near the Rogers Centre. A witness said the barrier was too close to the entrance and said it has since been moved.

With a report from CTV Toronto's Austin Delaney