As part of efforts to fight the COVID-19 pandemic, NUS was divided into zones, with three zones (A, B and C) covering the Kent Ridge Campus, one zone (D) covering the Bukit Timah Campus and one zone (E) covering the Outram campus. A PDF map of the zones can be found here.
As such, ISB services had to be revised to reduce intermingling of students across zones, with each zone being served by one or two routes named after the zones they serve. To distinguish the zoned services from regular services, the zoned routes were named using double letters instead of single letters. The zoned routes began operations from 20 July 2020.
The zoned ISB routes all linked bus stops located within their zones to key neutral/shared areas, such as Kent Ridge MRT, University Town, University Health Centre and PGP. There was no coverage between faculties in different zones, and students were only allowed to board buses corresponding to their zones.
To board the bus, students must enter from the front door and show their uNivUS safety profile to the Bus Captain in order to help enforce zoning.
My write-ups on the zoned routes can be found at the following articles: AA1/AA2, BB, CC/CCX and DD1/DD2. Operational information on the zoned routes was found at OCA’s website here; I will also add them into this Telegram sticker pack, replacing the old routes.
I like that the zoned network effectively reduced mingling between the zones. For example, for students reaching campus via Kent Ridge MRT, Zone A and B students do not mix with Zone C students as the latter will board the bus into campus at Opp KR MRT. Similarly, for campus residents heading from Central Forum back to UTown, Zone A students will wait at CLB for AA1 while Zone C students will wait at IT for CC.
It is not currently known how long campus zoning will last, but I expect these routes to be in use at least until the end of AY20/21 Semester 1 in December 2020. On 31 October 2020, NUS announced that the zoning policy will be lifted from 6 December, but no details have been announced as to whether bus routes will change.