SEPTA wants to split the line into two routes: A northern route — which would remain the 23 — would go between Chestnut Hill and Chestnut Street in Center City. The southern route — which would be christened the 45 — would go between Noble Street in Eraserhood to Oregon Avenue in South Philly.
Source: SEPTA Wants to Split the 23 into 2 Routes: The 23 and the 45 | News | Philadelphia Magazine