February 04, 2025

After a quick 20-hour travel flight (yesterday) we arrived in Athens, Greece.  A tour of Greece and the Greek Isles had been on my bucket list for the last 40 years, so I was excited.  After arriving in Athens, we boarded a bus which would take us to the waiting ship where we would spend the next week.  The bus chaperone pointed out several points of interest as we ‘whizzed by’ amid rush hour traffic, but the drive was mainly accomplished in silence.  As we moved along, I noticed the retainer walls that flanked both sides of the motorway.  The noise barriers were made of metal posts that had clear 10-foot (3 m) inserts, not the concrete sound walls I am used to seeing in the US.  The other aspect that interested me were the bird silhouettes placed on each panel of the noise barrier.

When I looked online, I found noise barriers (also called a soundwall, noise wall, sound berm, sound barrier, or acoustical barrier) are exterior structures designed to protect inhabitants of sensitive land use areas from noise pollution. Noise barriers are the most effective method of mitigating roadway, railway, and industrial noise sources, other than cessation of the source activity itself.  Extensive use of noise barriers began in the US after noise regulations were introduced in the early 1970’s.  Several different materials are used for noise barriers, including masonry, earthwork or berms, steel, wood, concrete, plastics, insulating wool, or composites.  Walls made of absorptive material mitigate sound differently than hard surfaces.  It is also possible to make noise barriers with active materials such as solar photovoltaic panels to generate electricity while reducing traffic noise.  Noise barriers can be effective tools for noise pollution abatement, but certain locations and topographies are not suitable for their use.  Cost and looks also play a role in the choice of noise barriers.  Potential disadvantages of noise barriers can be blocked vision for motorists and rail passengers.  While glass elements in the barriers can reduce visual obstruction, they require regular cleaning, provide an expanded target for graffiti, and create a possibility of bird strikes in the clear barriers

These disadvantages were evident in the barriers along the motorway in Athens.  Environmental noise barriers are common in Greece to reduce noise being emitted from outdoor installations or sources of traffic/railway noise.  Most such projects involve the construction of opaque or transparent noise barriers or even entire enclosures in cases of small/medium-size installations.  Each of the clear glass panels along the motorway had a bird silhouette emblazoned on it.  It took me a while to figure out why these silhouettes were on the panels.  Then I remembered several past blogs where I discussed the problem of bird strikes.  The bird figures warned any birds there was a solid surface, or at least another bird they needed to avoid.  There were a few sections of barriers that did not contain bird silhouettes.  Interestingly, these sections were heavily tagged with graffiti.  While such tags are considered an act of vandalism by some, many display an elaborate style and can often be identified through their uniqueness and methods.

Thoughts: The bird silhouettes and graffiti tags on the noise barriers were both a way of making a presence known.  The creators of the barriers wanted to make their presence known to keep birds from flying into the walls.  The graffiti was an effort by the taggers to let others in the city know they existed, and their presence mattered.  The desire to be recognized seems innate to humans.  It is even more so as we seek to create respect and unity among us all.  Act for all.  Change is coming and it starts with you.