• From the US 1 study and design in Adventura (FL):

Over a 10-year period, over 35 different designs were proposed to alleviate congestion at this intersection all rejected, most being freeway-style interchange designs before the Echelon Design was selected

Three major community forces initially opposed plans for a conventional freeway-style interchange design. All but a shopping center owner was convinced the Echelon design would work and lent their support accordingly. After construction, the market impacts to the shopping center were less than feared: a subsequent independent market research study showed that the shopping centerB s market area had nearly doubled because the center could be reached with less delay on the roadway system.

The presence of an active railroad line forced the structure design to have a greater clearance height (21 feet) and the vertical curve had to crest west of the intersection to clear the railroad. These factors combined to make this particular application both larger and more expensive than a typical Echelon design application.

The only post-construction safety concern that needed to be addressed was the southbound US 1 approachB s permissive left turn on a crest curve. While sight distance was adequate, several collisions prompted a signal change to allow only protected lefts, and the minor accident problem has since disappeared.