Around 100 metres of the track was subject to heavy watering on Thursday night after someone opened the control box and initiated the sprinklers for that section of grass.

It continued a wretched run of luck for the club though they were given the all-clear by stewards to go on with yesterday's races.

Twice in the space of a few months leading up to February's Bathurst Cup, watering malfunctions impacted on the club.

During a race late last year, sprinklers popped up and forced riders to take their mounts through streams of water at the top of the straight.

Unintentional over-watering in January forced a meeting to be called off, and Racing NSW subsequently suspended the club's racing licence altogether, lifting it briefly for the cup meeting.

Club general manager Michelle Tarpenning thought their troubles were behind them but was shattered to find out what had happened at daybreak yesterday.

"I was devastated to think that someone would do this to a club that has already had such a rough trot," Ms Tarpenning said.

"Someone has actually opened the control box and opened the sprinklers from the 800 to 700 metre areas of the track. We've reported it and it is a police matter now.

"Luckily the stewards rated that particular section as a heavy 10 and cleared us to proceed with the races."

With trainers coming from right across the region as well as Sydney, another abandoned meeting would have been a disaster for Ms Tarpenning and her staff as well as trainers keen to race on their home track.

"[Bathurst trainer] Dean Mirfin was pretty devastated to hear about it too," Ms Tarpenning said.

"He has eight runners in total today and a lot of the locals have runners.

"I basically started calling trainers from about 6am to try and let them know what was going on and when the stewards made their decision it was a relief to be able to tell them it would go ahead.

"This was definitely not a malfunction. Somebody did this."

Bathurst police confirmed that Ms Tarpenning's suspicions look close to the mark.

Inspector Mark Wall said police were called to the course early yesterday morning to investigate a break-in. 

Insector Wall said it appears someone broke in overnight and turned on the sprinkler system. 

Police do not know what time the break-in occurred but said it appears the sprinklers had been going for some time.

Inspector Wall said some property was also stolen in the break-in. Police are still investigating how entry was gained.

Investigators with the Chifley Local Area Command crime scene unit will be conducting a detailed investigation at the track.