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Site reconnaissance and survey planning
Reviewed the proposed jetty location, site access, shoreline conditions and survey requirements to plan land- and water-based data collection.
Home › Case Studies › Lake Naivasha Bathymetric Survey
Project Case Study · Lake Naivasha, Nakuru County, Kenya
Bathymetric & Hydrographic Survey in Kenya for Jetty Design
How Skymap Africa integrated single-beam echo sounder (SBES) depth measurements, a remote-controlled survey boat and GNSS RTK topographical surveying to map the shoreline and lakebed for a proposed jetty at Rubi Ranch Lake House.
Bathymetric mapping · Hydrographic surveying · GNSS RTK · Integrated terrain modelling
Project overview
Connecting the shoreline to the underwater terrain
A reliable jetty design starts with understanding both sides of the waterline.
Skymap Africa was engaged by Rubi Ranch Lake House to undertake a combined topographical and hydrographic survey at Lake Naivasha, Nakuru County. The objective was to provide a consistent picture of the landward shoreline and submerged lakebed around the proposed jetty alignment.
Rather than treating the land and water measurements as separate datasets, our team coordinated GNSS RTK ground observations with sonar depth soundings. The datasets were processed and referenced to create an integrated elevation model for engineering interpretation.
This approach helps project teams assess shoreline levels, underwater gradients and the relationship between the proposed structure and the lakebed.
Project locationLake Naivasha, Nakuru County, Kenya
Survey approachTopographical + hydrographic
Depth acquisitionSingle-beam echo sounder
ApplicationProposed jetty engineering design
Survey methodology
A coordinated bathymetric survey workflow
Skymap Africa combined shoreline control, sonar acquisition and geospatial processing to develop useful underwater and land elevation information.
02
GNSS RTK shoreline and ground survey
A CHCNAV multi-constellation GNSS receiver, used with the MUYA CORS network, captured shoreline topography and relevant terrain features.
03
Single-beam echo sounder data collection
A calibrated Chirp single-beam echo sounder mounted on a remote-controlled survey boat recorded water depths along planned survey lines, synchronised with GNSS positions.
04
Data processing and elevation integration
Ground survey observations and sonar records were checked, synchronised and reconciled to produce an integrated representation of the shoreline and lakebed.
Survey outputs
Bathymetric maps and engineering-ready survey information
The processed information provides a practical spatial reference for interpreting the lakebed, shoreline transition and proposed jetty alignment.
Project deliverables
What the integrated survey provides
Deliverables are tailored to the project brief and may include the following engineering and geospatial outputs.
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Bathymetric and topographic map
Combined mapping of surveyed land and underwater terrain in a coordinated layout.
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Bathymetric contours
Depth contours that communicate lakebed shape, gradients and depth variation.
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Longitudinal profiles
Profiles extracted from the integrated terrain model to support assessment of a proposed jetty alignment.
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CAD-compatible drawings
Digital survey drawings and PDF plots for common CAD-based engineering workflows.
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Integrated elevation model
A connected representation of shoreline topography and underwater terrain for engineering interpretation.
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GNSS-referenced survey data
Ground observations tied to the project coordinate reference approach for a consistent landward baseline.
Our capabilities
Bathymetric and hydrographic survey services in Kenya and Africa
Skymap Africa supports engineering, water-resource and infrastructure projects with hydrographic data collection and integrated geospatial survey solutions.
Lake, river and reservoir surveys
Underwater depth measurement and submerged terrain mapping for inland water bodies.
- Lake and river bathymetry
- Dam and reservoir surveys
- Waterbody contour mapping
Port, jetty and dredging surveys
Hydrographic information to support marine infrastructure planning and construction.
- Jetty and harbour surveys
- Dredging and reclamation support
- Nearshore depth mapping
Sedimentation and volume assessment
Repeat survey data to help assess changes in bed levels and water storage capacity.
- Siltation and sedimentation studies
- Reservoir capacity assessment
- Change and volume analysis
Project workflow
From field measurements to design-ready data
01 / PLAN
Understand the site
Review project objectives, site access, shoreline conditions and survey limits.
02 / SURVEY
Capture land and water
Measure shoreline terrain with GNSS RTK and submerged depths with sonar.
03 / INTEGRATE
Unify reference levels
Process and coordinate terrestrial and hydrographic datasets into one model.
04 / DELIVER
Prepare survey outputs
Produce maps, profiles and digital files for engineering interpretation.
Frequently asked questions
Bathymetric survey FAQs
What is a bathymetric survey?
A bathymetric survey measures water depths and maps the shape, elevations and contours of submerged terrain such as a lakebed, riverbed, reservoir bed or seabed.
Why combine bathymetry with a topographical survey?
Combining underwater depth measurements with shoreline and land elevations creates a connected site model. This helps engineers understand the relationship between the waterbody, shore and proposed infrastructure.
What equipment was used for the Lake Naivasha survey?
The project used a calibrated Chirp single-beam echo sounder mounted on a remote-controlled survey boat, together with a CHCNAV multi-constellation GNSS receiver and the MUYA CORS network for shoreline surveying.
What are the deliverables of a bathymetric survey?
Depending on the project scope, deliverables can include bathymetric contour maps, depth data, integrated topographic and bathymetric models, longitudinal profiles, CAD drawings and reports.
Can bathymetric surveys measure dam sedimentation?
Repeat bathymetric surveys can help compare bed levels over time, identify sediment accumulation and support reservoir storage-volume assessment. The survey design depends on the waterbody, depth range and project objectives.
Where does Skymap Africa provide bathymetric survey services?
Skymap Africa is based in Nairobi, Kenya and undertakes surveying and geospatial projects in Kenya and across East and Central Africa, subject to project scope and mobilisation requirements.
Planning a jetty, dam or lakefront project?
Talk to Skymap Africa about bathymetric mapping, hydrographic surveys and integrated shoreline data.