Increased use of the Gracefield Branch for shunting operations for Hutt Workshops necessitated a change in working practices on the line in 1929. Up to this time, race trains had been operated under Train Staff and Ticket regulations. The new method of train working for the line was to use these regulations from Woburn to the Hutt Workshops; the Line Clear Working method beyond. This required the installation of a telephone at Hutt Park to communicate with Woburn for the purposes of train control. It was proposed to construct a small shelter at Hutt Park for the telephone, but it was also noted that the telephone could be located in one of the workshops buildings along with the ticket apparatus.
