A water main running through Vancouver's Stanley Park that supplies most of the west side of the city has been leaking for six weeks, despite efforts to repair it.

The water is leaking from a hole in one of the main regional supply pipes which is located several metres underground between Lost Lagoon and the park causeway.

The pipe belongs to the regional district of Metro Vancouver which it is leading the repair efforts, according to Vancouver city manager Sadhu Johnston, who confirmed the leak Wednesday.

The pipe was installed in the 1930s and has not been problematic until now, but long term plans involve twinning this section of water main to increase capacity and resiliency for anticipated population growth, according to Metro Vancouver. 

Repairs underway

Staff were on site at Lost Lagoon this morning but it's unclear how far along crews are in the process of patching the hole.

"Through the work done this past weekend, we were able to establish the exact location, nature and orientation of the leak and are now preparing detailed plans to complete the repair. The site conditions are very constrained and staff are working to minimize impacts to traffic," said Greg Valou, media relations officer with Metro Vancouver.

Normal water pressure is expected to be maintained while repairs take place, and the Ministry of Transportation and Infrastructure is involved in the process to minimize traffic impacts on the busy causeway nearby.

Daily water demand for the region is about 1.5 billion litres per day, and the initial estimate for the leak is approximately 430,000 litres per day, according to Valou.  

Officials say the escaped water is being de-chlorinated, tested and monitored to make sure it doesn't contaminate Lost Lagoon and affect wildlife.

"At this time, the water runoff is being redirected into Lost Lagoon," said Sandhu. "Lost Lagoon is not expected to be negatively impacted by the spilling water."