A brand new water main is being installed to service Aamjiwnaang First Nation.
Work on the $1.4 million project got underway Monday, and is expected to continue through December.
The 10 inch pipe is being installed along a 1.3 kilometre stretch of South Vidal Street, from south of Suncor's gate to the Praxair facility.
It's being undertaken by Schouten Excavating, and subcontractor Rapids Drainage.
The roadway is closed to passenger traffic in that area, but the city has made arrangements with nearby businesses to allow their trucks to use the road.
Construction Manager Rob Williams said the project began with commissioning of a temporary water main.
He said the improvements are much-needed.
"There's a water main that goes east to west through Aamjiwnaang, and another one that is being replaced as well," said Williams. "We've seen a number of breaks in recent years. This is going to improve available fire flow and improve consistency as well."
The city said the water main will predominantly be installed by horizontal directional drill, so there will be less disruption but some excavation will still be required.
Williams said there are two more years of water main improvements planned.
They'll be fixing the area of the south Sarnia limit on LaSalle Line and another pipe at Aamjiwnaang.
About 73 per cent of the project is funded under the Investing in Canada Infrastructure Program (ICIP), with the City of Sarnia and Aamjiwnaang contributing the remainder.