"It's devastating for our club," she said.
"The race control building is pivotal for our club because if we don't have that race control we don't have a race meeting - it's as simple as that.
"We're a not-for-profit club and we don't have this kind of money. We're just lucky we have insurance whereas a lot of other clubs don't."
Wallace said the first big race meet for next year is planned for the January Auckland anniversary weekend and is expected to attract more than 100 racers.
"I hope we're ready," she said.
She said that while the cost is expected to be covered by insurance, the damage would sill take up plenty of volunteer hours that could be better spent improving the club elsewhere.
The club has also been consistently targeted by vandals and thieves recently.
Wallace said vandals had already broken into the race track and broken the glass windows of the race control building.
Wallace said that since a cycle path was put in the nearby park, giving better access to the area, the attacks seem to have gotten worse and led the club to consistently upgrade its security with improved alarms and security cameras.
She said the latest fire seems to have started in the area around the race control building.