Delve, 21, who missed the whole of last season while he recovered from knee reconstruction and shoulder operations, requires keyhole surgery on a calf problem.
"It's a setback," admitted Delve.
"But the procedure is straightforward and I hope to be back around the beginning of the season.
"In the grand scheme of things after a year away from the game making sure my body is fully repaired after the knee and shoulder operations, another few weeks' wait is not too much to bear.
"It just makes me all the more determined to get back out there on the pitch as quickly as possible."
However Bath conditioning coach Chris Mallac does not regard Delve's problem as serious, and has said he expects Delve to fully recover soon.
He would only be sidelined for around six to eight weeks," he said.
Delve developed a condition in his calves called compartment syndrome, where the muscles in his calves become too big for the connecting and surrounding tissue, making the area pressurised and causing pain.
"We could break it down through intensive massage, but the more likely option is for the player to undergo straightforward keyhole surgery," said Mallac.
And Bath coach John Connolly said: "Gareth is training with the rest of the squad at the moment but he will require surgery to correct the calf problem at some stage.
"We could let him carry on training and have him available for the start of the season but we would be running the risk of him breaking down completely at any time
"That being the case, it's better that he has the operation now and maybe misses the start of the season rather than face the probability of missing more games after the season starts."