Workers replace a water main more than a century old on Milwaukee Avenue as part of a major improvement project. View Full Caption DNAinfo/Paul Biasco

LOGAN SQUARE — One major water main replacement project is underway in Logan Square and a second is about to begin as early as Tuesday.

The two projects will involve replacing pipes that date to 1879 and 1889, respectively, which are some of the oldest in the city, according to a spokesman with the Department of Water Management.

Both projects will result in lane closures that could last months and will require residents whose homes are hooked up the mains to flush their pipes.

Residents could also face unexpected disruptions in their service during construction.

The first, a replacement of a main along Milwaukee and Sacramento avenues is already underway.

The second project will involve replacing the main below Logan Boulevard and is scheduled to begin Tuesday.

"This is a big project," said Gary Litherland, a spokesman for the Department of Water Management. "We are dealing with 100-year-old pipes here. There could be service disruptions without a doubt for something this old."

The Milwaukee and Sacramento project is replacing the main on Milwaukee from Belmont to Diversey, on Milwaukee from Logan to Fullerton and on Sacramento from Logan to Milwaukee.

The Milwaukee Avenue phase involves expanding capacity from a six-inch diameter pipe to eight- and 12-inch pipes.

That project will be complete in August.

During working hours the streets will be closed to traffic, but residents will be allowed to get to their homes.

The Logan Boulevard project will also be an upgrade to larger pipes to allow for expanded capacity.

The work on that project, that will stretch from Albany Avenue to the Kennedy Expressway, is expected to be complete in August.

Portions of the parkways along the boulevard will be dug up as part of the replacement project.

“As old as they are I would not be surprised if there are not a number of service interruptions throughout because the main is going to be pretty fragile because of its age," Litherland said.

Litherland suggested residents keep extra bottled water on hand in case of unexpected interruptions.

The Department of Water Management will be informing residents of instructions to flush their pipes once the main in their area is replaced.

The department will be putting door hangers on residents' doors as notice.

The flushing will be required because vibrations and disturbances to the lines leading to peoples' homes, many of which are lead, cause lead and other particulates to leak into the line.

"It's just to flush out any sediment at all in there, lead as well," Litherland said. "Their service line will be connected to a new water main. It's just a good precautionary step.”

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