Calgary officials announced a new water use target of 485 million litres per day, thanks to improved water capacity and distribution.
Michael Thompson, Calgary’s general manager of infrastructure services, explained in a Sept. 3 update that one of the key learnings from the June water main break looked at new ways to improve water capacity and distribution by reconfiguring existing pumps to reroute the flow of water.
“This is incredibly challenging as we have a complex water network with over 5,000 km of pipe and many underground storage reservoirs and underground tanks where we store treated drinking water prior to pumping it to homes and businesses,” Thompson said.
The Calgary team tested a new configuration to move water throughout the city over the last number of days, allowing them to sustainably move an extra 35 million litres of water throughout the system every day until the end of construction.
Any water use under 485 million litres per day is now sustainable. At this rate, underwater storage tanks can be comfortably restored overnight for the following day.
“We can manage unanticipated events such as a large fire or other emergencies and take our pumps offline for required maintenance,” Thompson explained.
When the demand rises between 485 and 500 million litres of water, the city has difficulty topping up storage tanks and is unable to handle unanticipated water needs. Water use above 500 million litres is not sustainable, Thompson said.
On Monday, Sept, 2, the demand for water exceeded sustainable levels to 505 million litres. Over the long weekend, demand remained under 500 million litres with 492 million litres on Friday, 475 million litres on Saturday, and 473 million litres on Sunday.
Stage four water outdoor water restrictions do not allow any outdoor watering and all automatic sprinklers must be turned off. Residents are also asked to reduce indoor water use. Go to Airdrie.ca for more information about the water restrictions in Airdrie.
Following the repairs resulting from a catastrophic break of Calgary's Bearspaw South feeder main in June, additional testing was done on the pipe’s condition. Several new locations were identified to need immediate repair, which shut down the Bearspaw water treatment plant and prompted water restrictions from Aug. 26 until the end of September.
Thompson reported 755 calls of water misuse in the City of Calgary since the water restrictions were put in place one week ago, including 521 reports for residential, 107 for businesses and industrial, and 60 for multi-residences. Five tickets of $3,000 were issued where required by bylaw officers.
Progress of repairs
Repair progress remains on schedule to be completed by Sept. 23, reported Francois Bouchard, Calgary’s director of capital priorities and investment. There are eight worksites along the feeder main with 21 pipe segments requiring repair over the coming weeks.
As of Sept. 3, excavation had been completed at 11 repair segments.
This weekend installation of rebar and formwork for concrete pouring began on excavated sites after inspections were conducted. Sept. 2 marked an important milestone as crews poured concrete around the first pipe segment.
The first four sites are estimated to be complete by the end of the day, Sept. 3. Work on worksites six to eight are scheduled to begin on Thursday, Sept. 5.
