Road construction authorities and environmental protection authorities would be well served to investigate this phenomenon further. It could be argued from an environmental point of view that all roadside barriers should be absorptive-faced or topped. The future Fast and free-flowing highways are clearly required to save time going to and from work. Cities which fail to build major arteries to clear the traffic quickly during peak hours become inefficient and hostile environments in which to live. Highway noise barriers make it possible to have freeways passing through urban residential areas without unduly reducing the standard of living for residents in areas near freeways.
Barriers are here to stay and they are quite economical.
Road construction and environmental protection authorities should continue to use reflective barriers for nominal noise reduction or traffic noise.