The jet-boat operator suspended all commercial rides on March 23.
However a skeleton maintenance crew will occasionally meet at Queenstown Marina, Frankton, to ensure the vessels are ready to assist in an emergency.
KJet Queenstown said on Facebook crews will check the boats over by reversing them into the water on a trailer and running them to a usual operational temperature.
"Should you see a KJet boat on the lake or rivers during this Covid-19 Alert Level 4 period, we will be on an emergency response call."
The company said it had worked to ensure minimal risk of transmission of Covid-19 between crew.