Amsterdam City Quay walls monitoring

Today, a part of the ancient quay wall in the famous city centre of Amsterdam collapsed. The City of Amsterdam is facing the huge task of assessing and potentially replacing 200 km of the quay walls along its charming old inner-city canals. Canal walls in the worst condition are at the top of the list for short-term replacement, usually surrounded by monumental buildings. These challenging aspects engaged even CNN to write about the costs and risks the Amsterdam quay project is facing and SkyGeo has been assisting in this project assessing risks and displacement. The part of the quay wall that collapsed today was on the list for short-term replacement, as our data showed displacement has been accelerating since 2016.

Today, a part of the ancient quay wall in the famous city centre of Amsterdam collapsed. The City of Amsterdam is facing the huge task of assessing and potentially replacing 200 km of the quay walls along its charming old inner-city canals. Canal walls in the worst condition are at the top of the list for short-term replacement, usually surrounded by monumental buildings. These challenging aspects engaged even CNN to write about the costs and risks the Amsterdam quay project is facing and SkyGeo has been assisting in this project assessing risks and displacement. The part of the quay wall that collapsed today was on the list for short-term replacement, as our data showed displacement has been accelerating since 2016.
The article by CNN compares the situation of the historic quai walls with an old verse every child in The Netherlands grows up with. The verse is loosely translated as: “Amsterdam, big city / It is built on piles / If the city would collapse / Who would pay for that?” CNN stated, even before the collapse, the verse is now becoming a reality as repairs are costly plus adjacent historical buildings are often susceptible to damage by nearby construction activities. Amsterdam has been transparent from the start around 5% of the quay walls have been reported as been unstable and in need of immediate replacement or repairs. Satellite data, PS-InSAR methods actually, are being used to monitor areas across the city.

Monitoring displacement is a vital tool in the efforts to preserve the physical charm and historical assets of this scenery. “The management of the quay walls and bridges has lagged behind in recent decades because it was not given the political priority it deserves and it is not a sexy topic,” says Sharon Dijksma, councilor for traffic and transport in Amsterdam, quoted in the article. To check the state of bridges and canal walls in the Inner City, the municipality is using traditional measuring bolts that track structural movements, but also more innovative methods such as satellite data, sonar and 3D scans.

InSAR considerably reduces monitoring time

SkyGeo teamed up with Deltares, the City of Amsterdam and TU Delft to setup the monitoring system. Recently they published a scientific publication on the reliability of PS-INSAR usage compared to regular ground levelling and general InSAR data. It describes how the PS-InSAR process can considerably reduce the current lengthy period required for levelling updates and verifies the improvement in reliability when using a locally optimized SkyGeo InSAR dataset. In short the publication shows the period from start to end is reduced from a minimum of 2 years to only 2 months. The quay collapse is proof the publication is well worth reading, as time reduction could save millions in extra repair costs, as inspections are already presented and maintenance is now planned. Unfortunately, the effort is too late for the Binnengasthuisstraat quay wall. But as other quay walls will be repaired and replaced in order of instability the idyllic wall construction of the famous canals will all be safe again after the project has ended.

To read more here is the full CNN article is available here, the Dutch news article about the news of the collapsinging quay wall and in case you missed it, this is our publication on the PS-INSAR methods used in the Amsterdam Quay wall monitoring project.