A series of water main replacements on Boston Street stretching from Union Street down to River Street has the potential to cause significant traffic disruptions to downtown, according to officials, and will run throughout the summer.

Connecticut Water Company (CWC) is replacing almost 100 year-old mains with wider and more reliable versions, according to CWC Public Affairs Director Dan Meaney. That work started last year where Boston Street meets Boston Post Road, Meaney said, and will replace the main all the way to the south-west side of the green, at the intersection of Boston and River streets.

Town Engineer Janice Plaziak said the town has no authority over the work or scheduling. Plaziak said she has passed on some residents complaints to the Department of Transportation about current road conditions on Boston Street.

Plaziak said she expected CWC workers to mill and overlay asphalt after they reach Union Street, which will mark the end of Phase 1 of the project.

Meaney said that Phase 1 is expected to be fully finished by the end of May, with work resuming in mid-April.

Phase 2, which Meaney said will begin immediately after, will replace mains and require excavation running along Boston Street from Union Street along the south end of the green to River Street. Plaziak said this could cause traffic issues, and the town will be working to reach out to residents and mitigate the disruption.

Phase 2 will run through the end of the 2020 construction season, according to Meaney.

Meaney said that during periods of the replacement, people are likely to lose water service “for an hour or two,” though CWC will give advance notice of whenever this is going to happen.

According to Meaney, the new mains are wider and more reliable, and specifically allow more water to run through fire hydrants. In Guilford specifically, Meaney said moving water from wells in Madison and a plant in Clinton make the new mains particularly important.

Plaziak said the town will continue to reach out to residents as the work goes forward.