Hydro Dam and Reservoir Surveys

AquaCoustic uses a range of technologies to survey dams and reservoirs, including scanning sonar, video, 3D sonar, 3D laser, profiling sonars and inspection class Remotely Operated Vehicles (ROVs).

The profiling sonar system provides better than three cm measurements at close range.

The portability of the system means that it can be easily and quickly deployed, keeping inspection costs to a minimum, and enabling frequent monitoring of critical areas.

Our underwater sonar can be combined with our above water 3D laser survey for a complete understanding of asset conditions.

The profiling sonar technique can be used to assess and measure vertical walls such as trash racks, gates, stop log guides and surfaces such as dam faces, under overhangs, or to measure bottom features, plunge pools, sink holes, rock trap debris, scouring and undermining in an efficient and cost effective manner.

Advantages

• Real-time on-screen review coupled with field observations allow on-site assessment of unusual features that may require further investigation.
• Economical and cost-effective measurement techniques enable regular inspections.
• Uses a combination of technologies for a comprehensive, accurate assessment.
• Data can be used in AutoCAD or other modeling software.
• The system can be deployed from a small vessel, ROV, through ice or from a fixed structure.

Applications

• Rock trap volume surveys.
• Identify and measure scour patterns and undermining from plunge pools or sink holes.
• Determine earthquake values by accurate measurement of dam slope profiles from a single point.
• Gather detailed data from hard-to-reach areas such as under overhangs, floating structures or vertical dam faces.
• Accurate data can be obtained up to the shoreline or beside vertical faces where boat soundings are not reliable.

Applications

• Volumes measurements for water inundation studies, dredging or siltation.
• Measure stop log guides, gates or other structures.
• Debris identification.
• Pre- and post-dredging quality control.
• Internal tunnel and pipe surveys.
• Repeat surveys to monitor conditions.

Deliverables

• AquaCoustic can match deliverables to your needs. The on-screen feedback in real time provides the ability to modify the survey on site.
• Hydro dam and reservoir survey deliverables may consist of all or some of the deliverables listed below.
• Each survey is documented in a report that is provided in digital form as well as a hard copy and includes drawings, tables and any video.

Selected sonar profiles

In some instances a specific sonar profile indicates additional information that may be helpful, or shows unexpected anomalies or features. For this reason selected profiles may be included in the report.

CAD ready X, Y, Z data

The sonar profiles, motion reference data and payout figures are recorded to our proprietary software. The software is also used for quality control and post processing, and outputs X, Y, Z files suitable for computer rendering.

Sonar rendered as 3D images

AquaCoustic renders the sonar XYZ data using various CAD programs, this helps us illustrate such areas as:

• Volume of build-up on trash racks
• Bottom trends
• Volume of siltation
• Comparisons with as-built drawings
• Areas of scour
• Size and shape of plunge pools
• Size and shape of sink holes
• Overlay repeat surveys for historical comparisons

3D sonar output

Our scanning or side-scan sonar images the bottom or sides of structures. This may indicate type of material, scour patterns, position of construction joints, and type and size of debris. A mosaic of these images can be overlaid on a 3D wire mesh surface.

Tunnel inspection data

The sonar data is graphically displayed to show the percentage of flow restriction due to sedimentation or debris. Tunnel diameter, volume of build-up, damage or other information is also provided as a table. This method is ideal for measuring areas such as:

• Position and volume of debris and other buildup
• Quantify scour and/or erosion
• Position of damage
• Area and position of turbulence

Inspection Class ROV

Our 1000 feet depth rated remotely operated vehicle (ROV) has a high resolution camera as well as scanning and profiling sonars a fiber optic umbilical ensures video quality. The ROV is capable of two knots under water.

Video

A high resolution digital video camera can be used to capture images of scour areas, sink holes and trash racks. A system to introduce dye can be implemented to test for water currents, and recorded. For larger areas a remotely operated vehicle is used to gather video and sonar data. The digital video survey images can form part of the report, if required.