City officials are warning residents to expect an especially busy construction season, especially near the University of Ottawa, as it tries to finish up transit and road projects ahead of a big tourism year in 2017.

'Avoid Nicholas Street'

This will be a critical year for building the first phase of the city's light-rail transit network, which is slated to open in 2018.

OC Transpo buses, seen here at Hurdman station, are expected to divert off the Transitway this spring at two more locations: between Lees station and Laurier Avenue and between Merton Street and Tunney's Pasture. (Doland Bourgeois/CBC) "This year the public should be prepared to feel the crunch," said Coun. Keith Egli, who chairs the transportation committee.

"The one thing the public needs to remember is, when possible, avoid Nicholas Street," said Egli.

That main artery between the Rideau Canal and the University of Ottawa will be reduced to one lane for traffic northbound.

Buses move off the Transitway this Sunday and onto a dedicated lane on Nicholas Street northbound. There will also be a lane for traffic. Southbound, traffic and buses will share two lanes. Nicholas will remain this way through 2018, and Egli advised motorists to use other Queensway exits.

The full length of the Transitway being converted from bus route to rail bed for the Confederation Line will close June 24 when construction begins on the section of between Merton Street and Tunney's Pasture and buses move to Scott Street.

By late summer the machines digging underneath the downtown are expected to meet. (CBC) Meanwhile, the machines that have been tunnelling under downtown are expected to finish excavating this year. By early fall, crews could begin testing trains on four kilometres of track near the eastern Blair end.

Big projects in the works this year

The city plans to spend hundreds of millions of dollars fixing up existing infrastructure and creating new pathways and roads. Motorists should expect delays of up to 15 minutes on busy arteries including Main, Queen and Rideau streets.

It will re-pave 150 kilometres of roads, including Wellington Street, Fallowfield Road and portions of the Airport Parkway.

The city will also break ground on a huge storage tunnel for sewage, a project that led to the expropriation of land under some Lowertown homes.

Some key dates:

April 24: Traffic on northbound Nicholas goes down to one traffic lane and one bus lane between Hwy. 417 and Laurier Avenue

April 24: Transitway closes between Lees station and Laurier Avenue. Buses bypass Campus and Lees stations

May 2 to Aug. 22: Pedestrian and cycling tunnel under Nicholas Street near the University of Ottawa is closed

June 24: Transitway closes between Merton Street and Tunney's Pasture station. Buses shift to Scott Street. Full length of Transitway needed for light-rail is therefore fully closed.