Frederick Gottemoeller - Bridgescape LLC

The Ohio River valley at the bridge site is a gigantic urban space defined by Mt. Washington to the west and the Manchester area of Pittsburgh to the east, all of which are visible from the Golden Triangle, the city's downtown. The Ohio River's navigation channel at that bridge is 900' wide, and the river itself is about 1200' wide. The key urban design challenge was creating a slim pedestrian bridge with a form visually powerful enough to make an impression at this scale while maintaining a positive relationship with the existing West End Bridge. The structural challenge was similar, creating sufficient stability over the required span with a lightweight pedestrian structure.

Since the new riverwalks had not yet quite reached the bridge site, both concepts included two new parks, one on each side of the river. The parks would give access to the water, generate activity along the riverwalks, and provide places where people from the neighborhood could come to throw a ball, throw a fishing line into the water, or just hang out with their neighbors. The parks would be connected by one of two new pedestrian/bicycle crossings.

Suspension Concept

A wide variety of bridge types across Pittsburgh's three rivers. In several places a suspension bridge is seen next to an arch bridge. The opposing curves of the two forms are very effective when seen together. Mr. Gottemoeller based his choice of the suspension form on this visual precedent. Because the Ohio River curves to the east the existing West End vehicular bridge is not actually visible from Point State Park where the Allegheny and Monongahela join. Mr. Gottemoeller offset the single suspension tower of the new bridge to the west so that the new pedestrian bridge would be visible from the Golden Triangle. Downtown observers would be aware of the proximity of the new bridge to the West End Bridge and would be encouraged to explore in that direction.

The bridge deck is a continuous variable width steel box girder that is y-shaped in plan. The arms of the Y create connections to both the Monongahela riverwalk and the bicycle paths of the West End. The girder relies for its stability on the stiffness of the box form itself and the girder's continuity with the y-shaped arms.

The fabric sculpture would occupy the three-sided pyramidal volume within the suspension network. The Tenara architectural fabric netting, would wave slowly in the wind, changing visual density and therefore color as viewed from various angles.

The pedestrian/bicycle path would be lighted with handrail lighting. The line of the deck would be defined by linear blue fixtures built into the deck edge. The tower and fabric sculpture would be lighted by uplights from the deck.

Arch Concept 

The new arched chord would be tubular in section and held away from the existing deck by a series of sloped struts. The struts would extend outboard to support light weight framing supporting the deck. The path would present a very thin and graceful edge to upstream observers. As the path curves up and away from the traffic on the existing bridge the noise and traffic - generated wind would diminish, until users are suspended in relative silence over mid-river. The path would be bordered on the inboard side by a continuous bench, providing copious opportunities to rest and observe the spectacular views.

The architectural fabric netting woven between the suspenders would wave slowly in the wind. Users walking along the path and viewers off the bridge would see a series of constantly changing color variations along the length of the structure.

The pedestrian/bicycle path would be lighted with handrail lighting. The line of the deck would be defined by linear blue fixtures built into the deck edge. Fixtures within the trusswork box of the arch would light its interior surfaces and the upper parts of the fabric sculpture. The lower parts of the sculpture would be lighted with uplights from the deck.

These concepts show that a memorable bridge can make an impression on viewers even at the immense scale of the Ohio River Valley. They also demonstrate how art can be fully integrated into a structural form. Unfortunately, the competition jury selected a different concept.

Mr. Gottemoeller formed and led the competition team, led the development of the suspension concept, served as the team architect and supervised preparation of the competition submission