Following the Jinan Central Business District (CBD) landscape design competition, Sasaki was asked to design the streetscape for 14 of the CBD’s 30 streets. Totaling some 26 kilometers, these streets connect with the district’s park system and vary from large-scale major urban connectors and buffer roads to small-scale park canopy walks and pedestrian-friendly recreational ring roads. Each street type has a different range of widths, speed limits, vehicular scales, and adjacent programming. The plan proposes the introduction of 30,000 new trees along the streets—the equivalent of 50 acres of forest.
The large scale of the site enables a systematic approach to streetscape design—from the larger ecological values that streetscape can add to the new district, to the expression of cultural and local identity. The design strategy manifests in three major layers: an urban forest comprised of street trees native to the region; a sponge network (rain garden) to alleviate the human interruption of the natural hydrological cycle; and an emphasis on design elements to cherish the locale, contextual, and cultural identities of the place.
The sheer numbers of trees intended for this project—30,000—goes far beyond merely beautifying an urban street. By pairing the six main native plant communities in Jinan with the major road networks, an “urban botanical garden” is created and linked through the city streets. The use of plants that are native to the region, yet rarely seen in urban settings, reminds urban dwellers of an almost forgotten botanical culture. The 40-100 meter wide green buffer at the south boundary of CBD provides a perfect location to showcase all the plant communities in a more natural setting. This unconventional way of planting approaches of streetscape is discussed at length here.
Various stormwater management strategies are applied to each street type, including permeable pavers, rain gardens, and bio-filters for areas with limited space. Careful calculations of urban runoff from impervious surfaces determine that the streets’ sponge network system will meet the Volume Capture Ratio of Annual Urban Diffuse Pollution, as specified in the local sponge city guidelines.
Native plantings maintain and celebrate Jinan’s intertwined iconographies of culture and botany. Abstracting the natural plant communities down to an “urban” form as street trees and rain gardens provides a unique character for an individual street while collectively reflecting on the beauty of local plants. This connects the design of the streetscape back to the city, the people, and their memories.
Unique botanical characteristics are highlighted beyond the plantings themselves, manifesting in the forms and patterns of paving, furnishings, and other physical design elements throughout the site. The lighting, seating, tables, and pavilions and gates throughout the development highlight unique cell structure, leaves and fruit of a particular native species. Steel is used for many of the furnishing elements—a nod to the steel factory which was sat on this site.