Our team leads data collection efforts to survey, map, and analyze site conditions to support development of sustainable design solutions. We collect conventional topographic survey data using total station and Real Time Kinematic (RTK) survey tools. We also collect hard-to-get bathymetric data using a range of watercraft equipped with sonar. Our fleet includes inflatable kayaks, rafts, motorized hard-shell kayaks and jet boats, which allows our teams to collect bathymetry in a wide range of rivers and flow conditions. Our team also includes FAA certified remote pilots that operate unmanned aircraft systems (UAS), or drones, to collect aerial imagery that documents a detailed representation of site conditions. For sites where quick and coarse scale topography is needed, we can use drones to create surfaces using structures from motion. We combine our field and aerial survey data with analysis of LiDAR-based terrain models to map and analyze project sites. We employ innovative use of GIS processing tools to produce Relative Elevation Maps (REM) that provide a powerful visualization of floodplain topography and landforms. NSD also has extensive experience with advanced spatial analysis and management of large GIS databases. We typically use GIS databases to store quantitative metrics of physical characteristics (such as gradient, width, and sinuosity), qualitative descriptions (soils, geology, and land use), and inventories of infrastructure within the stream corridor (roads, levees, houses).
