Locomotives doing the hard yards at the front end of the Wairarapa's passenger carriage units are also at the front end of low emission technology.
While you might call them 'vintage' at around 40 plus years old, they have been modified a few times over their life and recently retrofitted with low emission engine kits. They are the only ones in the country, and are exclusive to the Wairarapa service.
Rolling Stock Engineering Manager for KiwiRail, Danny Singh, says the decision to upgrade these particular locomotives was to reduce fume levels in the Remutaka Tunnel. The low emission retrofit involves pre-modification testing, retrofitting the engine with a low oil consumption power assembly and injectors that reduce emission levels, and post modification testing to check how it's working.
"After testing, we've found that the amount of particulate matter (tiny particles in the air) has decreased a lot, with levels dropping to between 30ppm (parts per million) and 80ppm," Danny Singh says.
Locomotive Engineer Tipi Penny (pictured above) is a Masterton local and says driving the low emission locos is the best job there is.
"I really love working on the carriage trains. If we ever had to stop and evacuate passengers inside the tunnel there will be less toxic gases, and that will be a lot safer for everyone."
Tipi has been a Locomotive Engineer since 2012 and returned to his home in Masterton in 2022 to take up the role. He is one of the three-strong Masterton team driving the low emission trains.
“I’m born and bred in Wairarapa. It makes sense to work back here where I’m from. It’s nice to be home, and to be around my people,” Tipi says.