The American driver of a van that crashed near Turangi on Saturday killing three Boston University students has been remanded on bail after a brief appearance in court.

Stephen Houseman, 20, entered no plea when he appeared in the Auckland District Court on Friday afternoon.

He has been charged with three counts of careless driving causing death and four counts of careless driving causing injury.

His next court appearance will be on June 8.

Bay of Plenty road policing manager Inspector Kevin Taylor said police were very aware that this was an incredibly difficult situation, but there was sufficient evidence to lay charges against the driver.

Insp Taylor said police had ruled out the use of drugs or alcohol by anyone in the crashed van, including the driver.

Daniela Rosanna Lekhno, 20, Roch Jauberty and Austin Brashears, both 21, were killed in the crash, while Meg Theriault suffered a serious head injury, a broken right arm and grazes.

The 21-year-old remains in a critical condition in Waikato Hospital but is breathing on her own.

Her parents, Todd and Deb Theriault, said their daughter was a fighter and her progress was heartening.

They have met Houseman's parents.

"We feel their pain and he now has a journey of recovery much like our daughter does.

"We understand there needs to be a court process and we support it. But that could have been any one of our kids at the wheel.

"This was an accident all - our kids were pursuing their dream. Nobody was intentionally doing anything that would harm anyone," they said.

The students had been travelling in a convoy on their way to walk the Tongariro Alpine Crossing when the crash happened.