BANGOR, Maine — The wintry weather expected this week has prompted the city to postpone the continuation of its $1.6 million downtown water and sewer line replacement project until Sunday evening, City Engineer John Theriault said Monday.

The work, which initially was to have started at 6 p.m. on Sunday, actually began earlier in the day so crews did not have to work in below freezing temperatures, Theriault said. Water needed to be applied to the pavement that was being cut and waiting until night time would have created icy conditions on the hill on lower Hammond Street where the project started, he said.

Moving ahead, however, city officials would rather wait for warmer temperatures to work at night as previously planned so as to avoid causing traffic issues downtown.

The National Weather Service’s forecast for the week ahead calls for a chance of snow late Tuesday afternoon followed by rain expected to change to snow early Wednesday morning.

More rain is expected on Wednesday, with a low of around 25 degrees that night.

While Thursday is expected to be mostly sunny, temperatures are expected to dip into the mid-20s overnight. The forecast for Friday, Saturday and Sunday calls for a chance of snow showers.

City officials said earlier this month that the water and sewer work involves replacing a more than 150-year-old sewer main and installing storm drains, catch basins, sewer manholes, a water main, hydrants, water services and new electrical and communication infrastructure at Hammond, Central and Main streets — one of the city’s busiest intersections.

The job is expected to last until early September, but city officials hope it will take less time. Work is expected to be done from 6 p.m. to 6 a.m. to limit traffic snags.

Traffic will be rerouted over side streets or limited to one lane of Hammond Street, though the one-lane phase of the project is not set to begin for several weeks. Motorists should plan on commutes over those streets to take several minutes longer than usual, Theriault said earlier this month.

Bangor Daily News writer Nick Sambides Jr. contributed to this report.