All eyes will be focused on London from July 27 to Aug. 12 for the Olympic Games. The city has been preparing for several years, and, unlike most previous Olympic host cities, has been making a concerted effort to create an infrastructure that will both meet the immediate demands of the games and serve the city well into the future. The buzzword being heard over and over again regarding London's Olympic preparations is "legacy."

It's a powerful premise: How do you create something of and for the time, that will also have a lasting effect? And it is a challenge faced at all scales—from cities to buildings. It even impacts how we light our important civic monuments.

The latest iconic piece of architecture to join the illuminated fray is London's Tower Bridge. The City of London is lighting it first for Queen Elizabeth II's Diamond Jubilee festivities (which are occurring as this issue goes to press), and then for the Olympics later this summer. But its lighting design is not getting very good reviews. U.K. lighting designers who have seen the installation in person are abuzz with less than favorable reports on Twitter; they seem especially concerned with the use of color and color blending. (The default setting is white, while color is reserved for special occasions.)

Press photos and videos of the bridge make it clear that something is off. The colors are garish—Disneyesque, really—and the lighting flattens the Victorian Gothic architecture instead of giving it an illuminated dimensionality. Also, there is no fluidity of light across the bridge as it spans the River Thames and as the bridge abutments knit themselves into the city fabric.

"As we transform our cities and develop their illuminated personalities, we should be asking some fundamental questions relating to good design and good urban-design practices."

The lighting design is attributed to a French firm, Citelum, which is known for lighting other icons such as the Eiffel Tower and the Valley of the Kings in Egypt. The new lighting scheme incorporates GE architectural LED systems, which replace floodlights, and is intended to remain in place for 25 years.

According to a statement from GE, the installation uses "6,500 feet of LED linear lights, 1,800 LED lamps, and 1,000 junction boxes with 16,500 feet of cable," and it will cut the bridge's energy consumption by 40 percent. Not surprisingly, GE is a sponsor of the 2012 London Olympics.

There is, of course, a tradition of illuminating buildings at night, and in color, often to mark important events or weather conditions. The Empire State Building in New York City comes to mind. As does the Berkeley Building in Boston (also known as the old John Hancock Building), which uses red and blue light to forecast the weather. A local popular rhyme explains the color code:

Steady blue, clear view.
Flashing blue, clouds due.
Steady red, rain ahead.
Flashing red, snow instead.

As we transform our cities and develop their illuminated personalities, we should be asking some fundamental questions relating to good design and good urban-design practices. For instance, does a building or monument need to have a nighttime presence, especially if it has never been illuminated before? If it does, how should it relate to other monuments and important structures in the city? Then there's the issue of how to light a landmark, and what kind of light to use.

Bringing light to our cities and important monuments should come from a sense of urban placemaking as well as from a desire to balance the everyday with spectacle. But at times, lighting decisions are in jeopardy of being made for the wrong, often purely commercial, reasons—especially when it comes to big events that take on a more corporate feel, and the need to bring in sponsor dollars (or, in this case, sponsor pounds).

We should light our cities and our civic monuments in a way that makes them better places to live, work, and celebrate—not because there exists the potential to sell a lot of lighting products.