What factors determine whether a rail project is built at street level (at-grade), below ground (below-grade), and/or aerial (above-grade)?
A variety of factors are considered when selecting between street level (at-grade), below ground, or aerial (above grade) configurations. These factors include a range of mobility, environmental, community, and cost considerations such as travel times, trip reliability, transit capacity, safety and security, right-of-way impacts, natural and cultural resources, traffic and circulation, visual and aesthetics impacts, noise and vibration impacts, community acceptance, construction impacts, as well as cost-effectiveness.
