Despite a mandatory outdoor water ban for many parts of Ottawa's south end, a Petro-Canada gas station in Barrhaven watered its lawn early Friday morning.

The city issued a sweeping outdoor water ban for residents and businesses in Barrhaven, Riverside South and Manotick on Wednesday. The ban was effective immediately and could last until mid-August.

The water restrictions are in place to ensure residents get an adequate supply of drinking water while crews replace a deteriorating water main on Woodroffe Avenue.

The water main, which was installed in 1976, broke twice in the last four years.

The ban blindsided residents in the area who can't understand why the work wasn't done earlier. The city says it didn't know the extent of the problem until recently.

Construction on the water main will begin in early May. It is expected to be complete by mid-August.