Hydropower plants
Run-of-river power plants along the Enns. Inspection of intake structures, trash-rack installations, weir structures (from the outside) and downstream stilling basins.
Waters · River
Underwater Inspection at the Enns — Hydropower Plants and Bridge Structures
The Enns, as a border river between Upper Austria and Styria, is continuously developed for hydraulic engineering with numerous run-of-river power plants. ScanSustain inspects power-plant facilities, bridge piers and flood-protection structures ROV-based — diver-free and audit-grade. Power-plant deployments require a coordinated shutdown. 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 Enns — subject to approval from local authorities and operators:
Bridge piers
Pier-base inspection for scour, corrosion and current damage at the numerous Enns bridges.
Bed ramps and bed stabilisation
Protective structures against depth erosion. Findings capture of stone displacements and ramp-base erosion.
Flood-protection structures
Protective dams, longitudinal structures, bank stabilisation. Capture of water-side components and assessment after flood events.
Typical Damage Patterns
What can be professionally captured at the Enns — a structured overview of the locally typical damage patterns:
Scour at bridge piers
Bedload-river-typical local erosion at the pier base. Depth extent is relevant to structural stability.
Bed-stabilisation erosion
Bed ramps are erosion-prone due to flood events. Structured capture of the scour geometry.
Bedload deposits
Sediment deposition in impounded sections and at structures. Quantity capture as a basis for dredging planning.
On-Site Methodology
Enns water is clear to moderately clear depending on discharge (visibility 0.5 to 2 m). ROV optics primarily in calm sections, sonar complementary for structured bed survey. The deployment window is significantly extended in late autumn and late winter under clear water conditions.
Water Conditions and Deployment Depths at the Enns
Unlike a lake, a river has no uniform depth — deployment planning is governed by the respective structure and the current discharge and flow conditions.
Typical depths
In the reservoir 3 to 10 m, at weir structures up to 14 m, in stilling basins up to 20 m — all values lie well below the ROV deployment limit.
Flow and water turbidity
Enns water is clear to moderately clear depending on discharge (visibility 0.5 to 2 m). In late autumn and late winter, the deployment window widens significantly under clear water conditions.
Exact water levels, flow conditions and visibilities vary depending on discharge, season and power-plant operation. For projects with accuracy requirements, we coordinate the current situation in advance with the operator or the water management authority.
Survey & Mapping at the Enns
Beyond pure condition inspection, power-plant operators, water management authorities and flood-protection associations at the Enns are increasingly asking for geometric data — for example for the scour-depth survey at bridge piers, the bed-profile mapping in the reservoir or after flood events, or the as-built documentation of flood-protection structures. With Survey & Mapping, ScanSustain offers photogrammetric and multibeam-sonar-based capture for this, delivering depth profiles, site plans and 3D models in CAD/GIS-ready formats.
Since the Enns offers only limited visibilities of 0.5 to 2 m depending on discharge, multibeam sonar carries the main share of geometric data capture here, complemented by photogrammetric imaging in clear, flow-calmed sections. This combination is particularly relevant for bridge piers and bed ramps when a geometric baseline is needed for rehabilitation or monitoring.
Regional Authorities and Bodies
Federal waterway: BMK (Austria). Provincial water management Upper Austria and Styria. Power-plant operators: ENERGIE AG, Verbund. Flood-protection associations as regional bodies.
Frequently Asked Questions
Are inspections of hydropower plants possible during operation?
No. ROV deployments at machinery installations, intakes or trash racks require a coordinated shutdown or drained inspection sections. Bridges and flood-protection structures outside the facilities can be captured during ongoing operation.
What depths are typical at the Enns?
In the reservoir 3 to 10 m, at weir structures up to 14 m, in stilling basins up to 20 m. All values lie well below the ROV deployment limit.
What response time is typical?
From the Burgkirchen base, the team reaches Enns sections between the mouth and Steyr in 1.5 to 2 hours. Response time for a first appointment is typically 1–3 working days.
Does ScanSustain also offer survey and 3D mapping at the Enns?
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 Enns require official approval?
As a rule, yes. As a federal waterway, the Enns falls under the BMK (Austria) as well as the provincial water management of Upper Austria and Styria. At power-plant facilities, coordination with the respective operator (ENERGIE AG, Verbund) is additionally required, and at flood-protection structures with the responsible flood-protection associations.
How is the bedload accounted for during inspection at the Enns?
Bedload-river-typical scour at the pier base as well as bedload deposits in impounded sections are captured in a structured manner. The sonar-based bed survey complements the ROV optics here, in order to precisely document scour geometry and sediment quantities as a basis for rehabilitation or dredging planning.
Plan a deployment at the Enns
Describe your use case — within 1 to 3 working days you will receive a concrete initial assessment with method selection and an effort indication.