CBH Group officially surpassed last year's total of 15.1 million tonnes on Saturday.
As of Monday morning, 15.8mt of grain had been delivered into the network, including 3mt in the past week.
CBH chief operations officer Mick Daw said that despite some growers nearing the end of their programs and a few harvest bans, more sites had continued to break records last week.
"Despite deliveries slowing down marginally last week, some sites have continued to break records," Mr Daw said.
"The Esperance zone has also broken its all time record of 2.8mt, with the zones total receivals sitting at nearly 3mt.
"These records have been made possible by our growers, frontline and maintenance teams, as well as our significant investment into expanding and enhancing our network sites."
Mr Daw acknowledged that this unprecedented volume had placed significant pressure on everyone involved with harvest, including growers, their families, employees, transporters and CBH staff.
"As the pace of harvest continues, we are actively working to ensure that we can maintain services for growers," he said.
"We are doing absolutely everything that we can to put more capacity on and ease pressure, which includes opening some old network sites and building emergency storage.
"We have successfully completed more than 2mt of emergency storage and we are continuing to build more, however more sites will continue to fill and close in the next seven to 10 days."
At time of print, CBH was unable to say which sites were expected to close next.
Albany zone
The Albany zone had good harvesting weather last week with warmer conditions across most areas.
It received 730,000t in the past seven days, until Monday morning, taking the total to 2.6mt.
The majority of growers have finished canola and are moving onto barley, wheat and oats.
The overall grain quality is good with some minor quality issues in areas which have been affected by water logging.
All sites are open and are receiving grain, with average cycle time slightly decreasing with the move to wheat.
Esperance zone
Harvest has been progressing well in the zone with more than 535,000t coming in the past seven days, taking the total to 2.9mt.
Wheat dominates the receivals now with barley tapering off in the zone.
The CBH quality team is placing focus on silo bags that have been stored onfarm and sending teams out into the field to sample and co-ordinate the delivery of that grain.
All sites still remain open, although storage space is becoming tight at many.
While most sites have outloading options to keep them open for grower deliveries, it is expected that some sites will have to close due to filling.
Geraldton zone
The Geraldton zone had a disrupted week with harvest bans and power outages.
Despite that, 420,000t were still received, taking the zone total to 3.3mt.
Some sites will close this week due to being full to capacity.
Kwinana North zone
The Kwinana North zone had good harvesting conditions in the past week, receiving 720,000t and taking the total to 3.8mt.
Mostly wheat is now being received with only small amounts of canola and barley still to come in.
Grain quality across all commodities is still tracking well and yields are above expectations at this stage.
All sites in the zone remain open for receivals although some sites will fill and close before Christmas.
Kwinana South zone
Outside the mid-week harvest bans, the Kwinana South zone received 680,000t, taking its total to 2.9mt.
Wheat is the main grain being received, with only small amounts of canola and barley still to come in.
Yields continue to well above expectations for wheat and minimal quality issues are being seen.
The average cycle time slightly improved this week but some sites will fill and close by the end of the week.
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