Bed ramps and bed slides
Bed-stabilization structures against depth erosion. Findings capture of stone displacement, scour at the ramp base and connection failures at the bank.
Waters · River
Underwater Inspection at the Salzach — Bedload, Bed Ramps, Flood Protection
The Salzach, an Alpine bedload river between the Hohe Tauern and the Inn confluence near Burghausen, is shaped by intensive flood-protection measures. ScanSustain inspects bed ramps, bedload barriers and bridge piers ROV-based — diver-free and with a sonar workflow for the sediment-clouded flow. Actual deployments are subject to approval by the responsible local authorities, facility operators and shipping administrations.
Characteristic Structures
These structure types can be inspected ROV-based at the Salzach — subject to approval from local authorities and operators:
Bedload barriers
Bedload-retention structures in the Salzach tributaries. ROV survey of the barrier crest, barrier base and downstream stilling basin.
Bridge piers
Salzach bridges in Salzburg city and on the lower reaches. Inspection of pier foundations under high bedload loading.
Flood-protection structures
Longitudinal structures, protective dikes with a water side, confluence structures. Structural capture of the water-side components.
Typical Damage Patterns
What can be professionally captured at the Salzach — a structured overview of the locally typical damage patterns:
Bedload deposits
Salzach-typical bedload transport leads to sedimentation in impounded sections and in front of structures. Volume capture as a basis for clearance planning.
Bed-ramp erosion
Ramp bases are susceptible to erosion due to trailing bedload and flood events. The depth extent of the erosion is relevant to structural stability.
Pier-base scour
Scour at the base of bridge piers is particularly pronounced due to the Salzach's high bedload. Structured capture of the scour geometry.
On-Site Methodology
Salzach water is heavily turbid in summer due to glacial melt (visibility 0.1 to 0.4 m). Sonar is the primary method for structural capture. ROV optics for detail findings with LED lighting at close range. The deployment window is considerably wider in late autumn and late winter when the water runs clear.
Water Conditions and Deployment Depths at the Salzach
Unlike a lake, a river has no uniform depth — deployment planning is governed by the respective structure and the current discharge and flow conditions.
Visibility and water turbidity
Salzach water is heavily turbid in summer due to glacial melt (visibility 0.1 to 0.4 m). During this phase, sonar is the primary method for structural capture.
Seasonal deployment window
In late autumn and late winter the flow is considerably clearer, which substantially widens the deployment window for ROV optics and optical detail findings.
Exact water levels, flow conditions and visibility vary by discharge and season. For projects with accuracy requirements, we coordinate the current situation in advance with the operator or the water management authority.
Survey & Mapping at the Salzach
Beyond pure condition inspection, water management authorities and flood-protection associations at the Salzach are increasingly asking for geometric data — for example for scour-depth survey at bridge piers, bed-profile mapping after flood events, or the as-built documentation of bed ramps and bedload barriers. With Survey & Mapping, ScanSustain offers photogrammetric and multibeam-sonar-based capture that delivers depth profiles, site plans and 3D models in CAD/GIS-ready formats.
At the Salzach, the summer turbidity caused by glacial melt (visibility 0.1 to 0.4 m) means that the multibeam-sonar component carries the main share of the geometric data capture, complemented by photogrammetric imaging in late autumn and late winter when the water runs clear. This combination is particularly relevant for bed ramps, bedload barriers and bridge piers when a geometric baseline is needed for rehabilitation or monitoring.
Regional Authorities and Bodies
The Salzach as a border river between Bavaria and Upper Austria. In Bavaria: the Wasserwirtschaftsamt Traunstein (Traunstein water management authority). In Austria: the Province of Salzburg (water management authority) as well as the Province of Upper Austria. Flood-protection associations as regional bodies.
Frequently Asked Questions
How does the inspection work in high sediment turbidity?
Sonar-based structural capture is independent of water clarity. Optical detail findings are captured at close range with lighting; the method switch is documented in the deployment protocol.
Are bridge inspections possible during ongoing traffic?
Yes. Pier inspection is carried out ROV-based without interfering with bridge traffic. Closures are only required for evidence-securing measures on the pier shaft.
What travel time is typical?
Lower Salzach: 0.5 hours. Salzburg city: 1 hour. Middle Salzach: 1.5 to 2 hours. Pinzgau and upper reaches: 2.5 hours.
Does ScanSustain also offer survey and 3D mapping at the Salzach?
Yes, as part of Survey & Mapping — currently as a pilot service, with photogrammetric and multibeam-sonar-based capture for depth profiles, site plans and 3D models in CAD/GIS-ready formats.
Does an ROV deployment at the Salzach require official approval?
As a rule, yes. On the Bavarian side, the Wasserwirtschaftsamt Traunstein (Traunstein water management authority) is responsible; on the Austrian side, the Province of Salzburg (water management authority) or the Province of Upper Austria. For flood-protection structures, coordination with the responsible flood-protection associations is additionally required.
How does the Salzach's high bedload affect the inspection?
The Salzach's high bedload leads to pronounced scour at the base of bridge piers, to sedimentation in impounded sections and in front of structures, and to erosion at the base of bed ramps. ScanSustain captures the scour geometry in a structured way and determines the sediment-deposit volumes as a basis for rehabilitation or clearance planning.
Plan a deployment at the Salzach
Describe your use case — within 1 to 3 working days you will receive a concrete initial assessment with method selection and an effort indication.