The class were also unable initially to reach Wellington via the NIMT, as the tunnels south of Paekakariki built in the 1880s by the Wellington and Manawatu Railway Company did not have enough clearance under the 1500V DC Wellington suburban electrification overhead wires. The operational practice remained the same as it had in the steam age, with an exchange with ED and EW class electric locomotives taking place at Paekakariki. The tunnel floors were lowered south of Paekakariki in 1967 and the DA class could then operate all the way through to Wellington. Access to Wellington before this time for the DA class could only be achieved via the Wairarapa line and the Rimutaka Tunnel.