National Mall, Washington, D.C.

For National Mall & Memorial Parks, National Park Service For our National Mall, Heritage Landscapes collaborated on an interdisciplinary team to address deteriorated conditions of turf, soil, drainage, irrigation and universal access.We began with research, and employed findings to focus design and construction documents on the visibility and continuity of the 180-foot-wide, 30-acre lawn between 3rd and 14th Streets NW. Our workincluded:

  • Research and summarize National Mall history and character 1810 to 2010,
  • Develop sequential overlay mapping showing widespread disturbance for NHPA Section 106 review
  • Pinpoint 1936-37 for National Park Service Mall construction influenced by Frederick Law Olmsted Jr.
  • Contribute historic constructs to design and construction documents
  • Stress recapture of continuous turf, domed grades and visual continuity

Our initial research and mapping project informed later restorative construction and historically sensitive accessibility design within the National Mall and Union Square turf panels and pedestrian walks. Hosting some 30 million annual visits and 3,000 events, sustainability, resilienceand functionality led theefforts to improve soils, add water-harvesting curbs and inlets, and build durable irrigation fed bysubgrade water storagecisterns. The team employed a simple, effective technique of crowning the lawn panels to elevates the turf in the view plane, deemphasizing walkways, streets and vehicles that bisect the Mall. The team achieved the desired outcome of a visually unbroken band of green.

Furthering this work, we are aided the DHM team in pre-design and costing for the National Mall walks noting the character-defining features of alignments, materials, widths, and views. National Mall walk replacement for universal access is the target for that effort.


Heritage Landscapes, lead DHM, National Mall Walks Pre-Design, 2019; lead HOK interdisciplinary team, Turf and Soils Restoration, 2009-201 National Mall Mapping 2010;


Heritage Landscapes, preservation landscape architects,Team lead DHM, pre-design; team lead HOK soils and turf, James Urban, IrrigationConsulting, Wiles Mensch Engineers


Our foremost goal was to restore the Mall’s grand aesthetics. . . Each member of our design team understood that it was a privilege and monumental responsibility to be a part of preserving our national landmark. This project is a prime example of how best to honor our public open spaces that have extraordinary national significance. HOK narrative for 2020 ASLA Honor Award General Design