What we do...
DML delivers a wide variety of coastal management services including, seabed mapping surveys and technical assistance with coastal projects for regional developments.
Our skills extend beyond waterborne activities to include surveying services in the wider coastal and inshore environment. We employ experienced land surveyors to assist in projects where land and sea activities overlap, thereby providing a total solution. We are specialists in operating in the challenging inter-tidal zone and have become adept at achieving the fine balance between good quality data coverage at a reasonable cost for our clients. The company also engages marine scientists specialising in biological and environmental monitoring and Resource Consents for specialist projects and has built long term alliances with specialist diving teams.
Hydrographic Surveys, Coastal & Environmental Services
- Shallow water Multibeam (MBES) and single beam (SBES) hydrographic surveys
- Precision depth surveys to International Hydrographic Organisation (IHO) standards.
- Surveys of critical areas (i.e. marinas, shipping channels, pipelines & cable routes)
- Dredging surveys and survey support for construction projects
- Tidal Studies and analysis (portable tide gauges)
- Magnetometer Searches for detecting ferrous objects (wrecks, anchors and chain, unexploded ordnance (UXO)), using a portable towed magnetometer.
- River surveys (cross sections and profiles) for environmental monitoring (erosion monitoring, flood protection, user impacts etc) - including land profiling of riverbanks
- Volumetric calculations of catchment areas, lakes, dams, reservoirs etc
- Beach gradient surveys (coastal erosion and hazard zone assessments)
- Side Scan Sonar surveys for seabed search and classification
- Measurement and analysis of tides and currents including ADCP, drogue tracking etc
- Seabed sampling and interpretation (including coring and diving services)
- Sediment transportation studies
- Positioning surveys (coastline, structures/features, navigation structures, moorings etc)
- Marine Biological and Marine Reserve surveys
Technical Capability
Our skills in the hydrographic survey industry are due to many years experience in planning, conducting and producing accurate hydrographic surveys for national and international charting requirements as well as for regional projects. DML maintains expertise in precise navigation, geodetic operations and tidal processes, which are all fundamental to the collection of accurate data.
Vessels and equipment are carefully selected to suit the particular requirements of each task. We operate our own fleet of Stabicraft and Senator in-shore survey boats for harbour and coastal projects, ranging in size from 3-9m. Other vessels are at our disposal, varying in size from small boats for intricate in-shore work, to medium and large sized workboats for larger off-shore surveys.
We use high-accuracy differential GPS or RTK GPS for vessel positioning as well as motion sensors to remove vessel heave. This information, along with depth data from digital echo sounders, is interfaced with our Trimble HYDRO Pro survey software. Data can then be presented as stand-alone sounding plans or as digital data in a variety of formats for integration with other digital and GIS systems. A variety of two and three-dimensional terrain models can also be produced using our contouring and surface mapping software.
We also have a complete set of modern survey instruments for land-based work including RTK GPS, total station instruments etc.
Other Services
- Hire of Survey Equipment
- Hire of Survey and work vessels
- Quality Control and validation of survey data
- Supply of skilled hydrographic and land surveyors
- Trimble DGPS Networks
- Trimble R6 RTK Positioning Systems
- Sokkia Total Stations and Levels
- Navisound and Tritech Echo Sounders
- TSS DMS25 Motion Sensors
- Tritech Side Scan Sonar
- Towed Discovery Magnetometer
- Trimble HydroPro and Terramodel Software
