Rijkswaterstaat has started renewing height scales at all national bridges over the main waterways from Gorinchem to Hoek van Holland. The current scales are often poorly legible, incomplete, or entirely missing.
This renewal is being used to comply with Waterway Guidelines to correctly display the actual clearance height, including safety height, relative to the water level. The renewed signage aims to improve the safety and accessibility of waterways.
Maintenance and better visibility
Many height scales are dirty due to weather influences and growth, making them difficult to read. A problem that has been a thorn in the side of many skippers for years. A cleaning action is not enough, as the dirt has completely penetrated.
Therefore, we are completely replacing the scales, including new frames and fittings. The lighting is also being restored or reapplied, so the scales are well readable even in the dark.
Waterway Guideline: no more safety heights
Every bridge over the waterway has a determining clearance height displayed on height scales on the bridge piers and on the fore height scales at some distance from the bridge. At some locations, a safety height is used; the actual clearance height is then reduced by that safety height. This provides a margin to prevent ships from being loaded to the maximum height limit, with an increased risk of collision as a result.
In practice, this margin is often taken by skippers as extra space in their calculations, which undoes the effect of the safety height. By renewing the height scales, we give substance to the Waterway Guideline Framework 2020 and the Shipping Traffic Signs Guideline 2023 which both prescribe to display the actual clearance height everywhere. There were already publications about this last year.
Phased introduction
In the coming months, the (fore)height scales in South Holland will be renewed under the responsibility of Rijkswaterstaat West Netherlands South, in collaboration with other managers such as ProRail and the province of South Holland. In the following years, other regions will also implement this renewal.
Bridges where height scales will be adjusted in the coming months
- Boven-Merwede: Merwedebrug Gorinchem (A27)
- Beneden-Merwede: Baanhoekspoorbrug, Merwedebrug Papendrecht (N3)
- Noord: Alblasserdamsebrug (Bridge over the Noord)
- Oude Maas: Dordtse bridges (railway bridge and city bridge), Spijkenisserbrug, Botlekbrug
- Hartelkanaal: Harmsenbrug, Suurhoffbruggen, Dintelhavenbrug
- Amer/Bergsche Maas: Keizersveer Bridge
- Hollandsch Diep/Haringvliet: Moerdijkbruggen (traffic bridge and regular railway bridge), Haringvlietbrug
- Bakkerskil: Bridge towards island de Zaag Krimpen aan de Lek
- Sliksloot: Stormpolder Bridge Krimpen aan den IJssel
National bridges that will not be included in the coming months will be adjusted during planned renovations in the coming years, such as the Van Brienenoordbrug, the Calandbrug, and the Algerabrug.
Desired end image
Eventually, all height scales in the Netherlands will be displayed in the same way, without safety heights. This process will take several more years.
More information
For questions, you can contact us.