The £33 million Swindon town centre project has been hampered as the site floods.
A Thames Water gaffe resulted in Fleming Way becoming into a lake this morning (Thursday).
The major redevelopment project aims to transform the area, which is described as the “main gateway to the town centre”.
The Parade underpass was demolished in recent weeks as work continues to flatten the site as a welcoming open space is created.
Swindon Borough Council is blaming today’s incident on Thames Water.
A spokesperson said that a connection to a new mains water pipe caused the flooding – leaving local residents and businesses without water.
In a statement, the council said: “Some residents in the town centre have lost water access while engineers from Thames Water work to repair a new mains water pipe that they recently installed under Fleming Way.
“It was caused by a failed connection to the new water main.”
They added: “The significant flooding is contained to the construction site and is not impacting Zurich, Tri-Centre, the Parade or any of the neighbouring buildings. All town centre roads remain unaffected.
“Thames Water are on site to fix the issue and pump water to clear the construction site. Check the Thames Water website for further updates.”