There’s a Bridge That Sings When the Wind Blows — And No One Knows How

There’s a Bridge That Sings When the Wind Blows — And No One Knows How (Image: Canva)

The Golden Gate Bridge sings in San Francisco, and it is a mysterious and eerie phenomenon that has drawn the attention of both locals and tourists in the city. Not, of course, like a choir, but when good winds blow in the right direction, it makes sounds--a deep moan or a haunting whistle--which travel over the Bay. The sound, which seems loud to some people and almost inaudible to others, starts at winds of about 35-45 km/h (mid-to-high gusts), particularly when the air passes through some retrofitted railings on its westward length.

This strange sound effect is a result of a wind retrofit project. To ensure the safety of the bridge during strong winds, new railing slats were put in place. These slats are slimmer and with smaller spacing, which has been created to benefit aerodynamically. However, engineers realised in advance that if the wind blows through them, the air may create vibrations and tones. How the effect can be so apparent is what baffled the spectators, whether it be a flute, a kazoo, or a chorus in the distance, particularly on a stormy day, or when the gusts blow consistently in the same direction, which is westward.

People have two different tones. One of those is lower, more rumbling and heard farther off; the other is higher and sharper and more piercing, when the wind takes a slight angle. The tones are different, depending on your standpoint. At times, drivers on the bridge can hear them when they are under their wheels and at other times they can be heard by people miles away. The sound was occasionally heard, during a storm, several miles away, and this caused amazement and the frustration of the people around.

Although people who have heard the bridge sing are praising it (or complaining about it), there remains some mystery. There is no well charted up exactly how loud it will get, what angles of wind form what kind of tones, and what the entire range of frequencies will do. Engineers are currently developing ways of reducing noise pollution without interfering with safety.

What is evident is that this bridge, known for its orange towers and breathtaking views, now also has some songs in the air. Not music created by men, but by physics, design, and nature working together in unforeseen combinations. It makes us of how the most well-known sights can be unexpected when the right time comes.