There is an increased interest from transit agencies to replace fixed-route
transit services with on-demand public transits (ODT). However, it is still
unclear when and where such a service is efficient and sustainable. To this
end, we provide a comprehensive framework for assessing the sustainability of
ODT systems from the perspective of overall efficiency, environmental
footprint, and social equity and inclusion. The proposed framework is
illustrated by applying it to the Town of Innisfil, Ontario, where an ODT
system has been implemented since 2017. It can be concluded that when there is
adequate supply and no surge pricing, crowdsourced ODTs are the most
cost-effective transit system when the demand is below 3.37 riders/km2/day.
With surge pricing applied to crowdsourced ODTs, hybrid systems become the most
cost-effective transit solution when demand ranges between 1.18 and 3.37
riders/km2/day. The use of private vehicles is more environmentally sustainable
than providing public transit service at all demand levels below 3.37
riders/km2/day. However, the electrification of the public transit fleet along
with optimized charging strategies can reduce total yearly GHG emissions by
more than 98%. Furthermore, transit systems have similar equity distributions
for waiting and in-vehicle travel times