Commissioned by the Treasury Department, Quennell Rothschild & Partners served as urban design consultants for a multi‑disciplinary team studying measures to ensure the security of the White House complex. Among the team’s conclusions was the need to prohibit vehicular traffic on Pennsylvania Avenue in front of the White House and the Executive Office Building.
After an analysis of the physical site, security issues, and historical considerations, the firm developed several alternative urban design plans to study the effect of closing this segment of Pennsylvania Avenue.
In preparation for public announcement of the avenue’s closure, the firm prepared illustrative drawings depicting the alternatives. Among them was the proposal shown, which extends Lafayette Park to the White House perimeter while allowing pedestrian access to the front fence. Other alternatives treated the closed portion of the avenue as a formal pedestrian mall.