ðə lˈaɪn wʌz ʌpɡɹˈeɪdᵻd tə mˈɛtɹoʊ stˈændɚd baɪ ɹᵻplˈeɪsɪŋ ðɪ ˌoʊvɚhˈɛd wˈaɪɚ wɪð ɐ θˈɜːdɹˈeɪl pˈaʊɚ səplˈaɪ ænd ɪnstˈɔːlɪŋ ˌɔːɾəmˈæɾɪk tɹˈeɪn pɹətˈɛkʃən.
The line was upgraded to metro standard by replacing the overhead wire with a third-rail power supply and installing automatic train protection.