Until last week he was being treated at Huntington Memorial Hospital in California. Plans to recuperate near his family in Nelson were shortlived after his condition suddenly deteriorated on his return.
He was admitted to intensive care then flown to Auckland's Middlemore Hospital.
Surgeons there removed titanium rods from his broken lower right leg after it was discovered his leg was harbouring deadly bacteria.
Samples from his bone and rods revealed at least three different types of infection. He was now on a cocktail of drugs.
Somervell said everything hinged on tomorrow's operation.
"The second clean-out I had on Friday was good and it looked like the infection was not coming back," he said. "If it's bad again then they will amputate the leg."
He said there were encouraging signs that gave him hope the leg could be saved.
Tests revealed good blood circulation thanks to a vein graft performed in America.
"I've got warm toes and the nerves are coming back. It feels like insects are crawling inside my good leg."
He said despite the unexpected change of plans he was enjoying spending time with friends keeping him company in hospital.
Meanwhile, three Special Enforcement Bureau personnel who treated Somervell on the day of the crash will be recognised with state awards for their actions.
Their extraordinary efforts and excellent patient care to save the critically injured young motorcyclist have earned them a clinical excellence award from the Emergency Medical Services Authority.
