Delta is a city in the Lower Mainland region of British Columbia, Canada, as part of Greater Vancouver. Located on the Fraser Lowland south …Delta is a city in the Lower Mainland region of British Columbia, Canada, as part of Greater Vancouver. Located on the Fraser Lowland south of Fraser River's south arm, it is bordered by the city of Richmond on the Lulu Island to the north, New Westminster to the northeast, Surrey to the east, the Boundary Bay and the American pene-exclave Point Roberts to the south, and the Strait of Georgia to the west.