Residents living in the area of Talfourd and Devine and nearby side streets are next in line to have their sewers separated.
Sarnia has applied for senior government funding which, if approved, would see the $5.5 million project completed by March 31 of 2018.
The city has for decades been replacing its old combined sewer system, which is prone to sending raw sewage into basements and the St. Clair River during periods of intense rain.
The project would see the federal government contibute $2.74 million and Ontario provide $1.37 million, leaving the municipality to fund the remaining $1.37.