70th Street Station was a new station on the Trolley Green Line built in Mission Valley to the east of San Diego from 2001 to 2005. The station's location was in a residential community that demanded a traditional look for the station structures. The challenge was to find a form that would satisfy local aesthetic tastes while promoting the strongly modern image of the new transit line in its Southern California setting. The inspiration came from new spaceplane designs that NASA was exploring at the time. NASA was studying a lifting body design with

a bulbous fuselage blended with small wings that had large dihedral winglets at their ends to give the vehicle lift and control during descent and landing (image below left). In the canopy structure design, the winglets were transformed into lightly dihedral edges along the eaves to provide grooves for rainwater disposal (image below right). Each

canopy was fabricated in one piece

entirely out of steel plate, based on semi-

monocoque structural principles. The

supporting columns comprised thick

walled steel tubes on massive footings

to resist seismic forces in a high-risk

earthquake area. All utility systems and

pipework ran inside the columns.