The Netherlands Filled This Motorway With Holes on Purpose

The Netherlands paved ninety percent of its motorway network with a surface that is roughly one fifth air. On purpose. It was not built to be quiet — that came ten years later, by accident. This is ZOAB, and it is slowly eating itself. The Netherlands paved 90% of its motorways with ZOAB, a surface that is 20% air. Here is why they built a road full of holes. This porous road surface was designed to handle heavy rain by letting water flow sideways inside the pavement. While the primary goal was safety, the unexpected benefit was a significant reduction in motorway noise. This complex road infrastructure comes with a cost. The open structure traps dirt and salt, causing the material to age faster. I examine the technical trade-offs of this design, contrasting the Dutch approach with standards in Switzerland and France, where frost and maintenance concerns often limit the use of this asphalt engineering. Subscribe for more technical breakdowns of the infrastructure around us, and let me know in the comments if you want to see how other road materials compare. ──────────────────────────────────── Water on a road is thinner than a coin, and it is the thing a tyre has to fight at motorway speed. For a century every road engineer answered the same way: make the surface waterproof and push the water off the side. In the nineteen-seventies the Dutch did the opposite — they opened the road up and let the water flow sideways inside it. It worked. It also made the road quieter, which nobody had asked for. And every year since, the same openness has been ageing the bitumen, swallowing the road salt, and filling itself with dirt. Switzerland looked at the same trade in twenty sixteen and gave back two decibels to avoid it. France advises against it above fifty days of frost a year. So why do the Dutch keep it? ──────────────────────────────────── CHAPTERS 00:00 Two trucks, same rain 00:27 ZOAB — what it actually is 01:41 The film of water under a tyre 03:30 Sideways, inside the road 05:43 The silence nobody ordered 08:13 Three bills, one cause 12:13 Why almost nobody else does this 15:25 The trade nobody voted on ──────────────────────────────────── SOURCES Rijkswaterstaat — Zeer open asfaltbeton (ZOAB) https://www.rijkswaterstaat.nl/wegen/... Rijkswaterstaat — Strooien en zout https://www.rijkswaterstaat.nl/wegen/... Rijkswaterstaat — Vorstschade https://www.rijkswaterstaat.nl/wegen/... VBW-Asfalt — Richtlijn Tweelaags ZOAB https://www.joostdevree.nl/images/a/a... CEDR — Technical Report 2017-01, "State of the art in managing road traffic noise: noise-reducing pavements", January 2017. ISBN 979-10-93321-27-1 https://www.cedr.eu/download/Publicat... Conseil général des Ponts et Chaussées (France) — Report 005051-01, "Les difficultés de viabilité hivernale sur l'autoroute A84", April 2007 https://igedd.documentation.developpe... IDRRIM (France) — Note d'information n°43, December 2020 https://www.idrrim.com/ressources/doc... ASTRA (Switzerland) — Monitoring lärmarmer Strassenbeläge auf Nationalstrassen, Standbericht 2024 ──────────────────────────────────── IMAGE CREDITS All footage, photographs and audio in this video were shot by me in the Netherlands and Belgium. All diagrams and animations are original work. The music is an original composition written for this video. Country outlines: Natural Earth, public domain. No third-party images, footage or music are used. ──────────────────────────────────── Some visuals in this video are explanatory reconstructions — diagrams and animations built to show how a mechanism works. They are not photographs of real events and are not presented as such. Every figure in this video is sourced above. Where a number could not be traced to a primary source, it is not in the video. #infrastructure #engineering #netherlands #roads #civilengineering