His bus company propose for no SD, 10 parking lots in int
reserve for each svc..
No SD? That is also crazy. Airport bus service will crash into
ceiling with 3.9m basements.
As for parking lots in int, it depends on the
peak frequency.
Low frequency (16-20 mins): 1-2 lots
Medium frequency (10-15 mins): 2 lots
High frequency: (6-9 mins): 3-4 lots
Very high frequency (<5 mins): 5-6 lots
There are only a few services in the very high frequency group
(e.g. 72, 179, 190)
Very long trunks (>25 km) will also have more parking lots
due to higher chance of bus bunching.