This reversal of the water flow in stage 1 of the NPI will reduce the draw on the Sunshine Coast's Lake Baroon during what is traditionally a dry time of year.
The north-south interconnector pipeline was originally built to send water from the Sunshine Coast to Brisbane during Queensland's prolonged drought, ABC News reported.
Peter Dennis, chief executive officer of Seqwater, said that water is planned to flow in a northerly direction along the NPI for one month but the company will monitor supplies on a daily basis and adjust if required.
He added that this switching of the NPI to supplement local supply in the Sunshine Coast from outside the region demonstrated the benefits of an integrated bulk water supply network.
Stage 1 of the NPI, which runs between Moreton Bay and the Landers Shute Water Treatment Plant near Montville, was completed in 2009 but until now it has only ever operated from north to south.
NPI stage 2, between the Landers Shute Water Treatment Plant and Noosa Water Treatment Plant, already flows in both directions. It has been reversed several times this year as Seqwater balances water storage and supply needs across its network.