Thirty stories over Hastings

The existing US 61 bridge in Hastings.

A tied arch design.

A cable stay design.

The iconic Hastings Sprial Bridge.

As design for the US 61 Bridge in Hastings continues, new concerns are arising about the proposed height of the bridge.

Three bridge types were considered during an environmental review of the proposed project. The Minnesota Department of Transportation (MnDOT) has decided the contractor will have the opportunity to decide between two of those bridge types – what are known as a "tied arch" or the "cable stay" (see photo inset).

The tied arch mirrors the format of the last two bridges at the location, and is of similar size and height. Initial plans for the cable stay alternative suggested a bridge of about 220 feet above the river. As designs have moved forward, the range of bridge heights has increased dramatically, and now the cable stay option would likely require a bridge 314 feet or about 30 stories above the river - which is over 120 feet higher than the blufftops just upriver.

Concerns over height on the bridge are unique, in that the height in question is around a structure that is not just next to the river, but in the middle of the river.

Presumably, the contractor will choose the design they believe to be least expensive. Part of the reason the cable stay design has increased in height is that it is believed a shorter cable stay bridge may not be cost-competitive with a tied arch bridge.

In other locations around the state, MnDOT has utilized a practice that in the traffic engineering field is referred to as context sensitive design. Such design ensures that the scale of proposed improvements is not substantially at odds with its surroundings. In this case, the height of the bridge tower would dwarf historic downtown Hastings, as well as nearby bluffs. The height of the bridge also increases the odds of impacts on the migratory birds who use the river corridor colliding with the bridge cables.

An initial analysis of the area suggests that the bridge could be seen from many miles away. In some of these more distant views, the bridge top would likely not be significant in the daytime – just a dot on the horizon. But even there, as night fell, the concern is that the bridge is a likely candidate for accent lighting, and the top of the bridge would be brightly illuminated. Further study of the bridge height and its impacts may be undertaken.

As FMR's letter to MnDOT indicates, FMR continues to strongly prefer the tied arch alternative, due to height concerns. FMR is working with the National Park Service to reduce the height of the bridge within the project design standards.