Mrs Stevens said it was "so awesome" to receive the award for her volunteer work over the past four years.
The association has raised $1.3 million for the project, which is part of the Gibbston River Trail.
She said it still needed $100,000 to reach its target by the September deadline.
The site is home to a rare pre-1900 fruit orchard and rock huts left over from the gold-mining era.
While one of the old huts, known as Rum Currie's hut, had earlier been restored, the remains of another hut and associated rock work has been uncovered and mapped.
Mrs Stevens said she spent 40 hours a week on the project.
She has been helped by community probation service workers to clear the site.
New Zealand Archaeological Association president Matthew Schmidt said the award was presented every second year to recognise outstanding efforts in public archaeology.
He said Mrs Stevens had contributed to the identification, protection, preservation, public awareness, enjoyment of and education about the archaeological site.
