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Lidar Fetch (USGS 3DEP point cloud for an area)

Public USGS 3DEP lidar for the area you pick, in the drawing's coordinates. Pick a boundary (or a window), pick a dataset from the ones that cover it, check the download size, and the ground points land in a LAS / LAZ file in your State Plane zone and units - with the dataset, URL and retrieval date stamped in the file, in the drawing and in the report. In Civil 3D it can also build a thinned TIN surface.

Command VDCLIDARFETCH · VDC Civil tab › Point Clouds panel
Public USGS 3DEP lidar for the area you pick, in the drawing's coordinates. Pick a boundary (or a window), pick a dataset from the ones that cover it, check the download size, and the ground points land in a LAS / LAZ file in your State Plane zone and units - with the dataset, URL and retrieval date stamped in the file, in the drawing and in the report. In Civil 3D it can also build a thinned TIN surface.

What it does

  • Datasets - every 3DEP collection whose outline touches the boundary, whole coverage first, then newest and densest, with year, estimated quality level and density.
  • Spacing - full density or 1 / 2 / 3 / 5 / 10 ft; coarser downloads less. The download size is shown before anything is fetched (hard stop at 2,000 MB).
  • Keep - ground only by default; an unclassified collection keeps everything but noise and says so (run VDCCLOUDCLASSIFY on it).
  • Output - LAS 1.4 / LAZ in the drawing's State Plane zone and units, NAVD88 heights; provenance in the file, an Xrecord in the drawing and the CSV in VDC Reports.

Good to know

  • Live service - the public AWS usgs-lidar-public bucket (anonymous) and a dataset index; tiles are cached under %LOCALAPPDATA%\VDC\LidarFetch.
  • Cached - re-runs reuse the tiles already downloaded; ESC cancels and writes nothing.
  • QL2 (about 2 points / m2) is planning-grade terrain: it will not resolve curbs, gutters or small structures.
  • Not every county is in the public bucket (Horry County, SC is not); the tool says so and points at the National Map download.
  • Civil 3D license set - ships in the Civil 3D bundle only since 1.117.1 (not on plain-AutoCAD seats).

Dialog

Lidar Fetch (USGS 3DEP point cloud for an area) dialog
Lidar Fetch (USGS 3DEP point cloud for an area) - VDCLIDARFETCH
Lidar Fetch (USGS 3DEP point cloud for an area) dialog
Lidar Fetch (USGS 3DEP point cloud for an area) - VDCLIDARFETCH
Lidar Fetch (USGS 3DEP point cloud for an area) dialog
Lidar Fetch (USGS 3DEP point cloud for an area) - VDCLIDARFETCH
Settings file: %APPDATA%\VDC\LidarFetch\settings.json

When to use it

  • A site needs an existing-ground surface for planning, earthwork or a quick pond check before the survey is in.
  • You want the actual lidar points (not the 1 m DEM VDCTERRAIN samples) to classify, slice or thin yourself.
  • A reviewer asks where the existing ground came from - the source, URL and date travel with the file and the drawing.

How to run it

  1. Run VDCLIDARFETCH; check the zone (the drawing's, or pick one), the point spacing (3 ft is a typical grading surface) and Keep (ground only).
  2. Set the output folder (blank = the drawing's folder) and LAZ or LAS; in Civil 3D tick the surface if you want one.
  3. OK; pick the boundary (or the window).
  4. Pick a dataset - whole-area coverage, newest and densest are listed first.
  5. Read the download size; Download (or Back for another dataset). ESC cancels while it runs.
  6. Read the summary: points kept, elevation range, the file, the surface; open the CSV in VDC Reports.

Options

  • Point spacing: full density or a target spacing - coarser reads fewer octree levels and downloads less; finer than the collection returns every point.
  • Keep: ground only (default); ground + road, water, bridge decks; everything except noise; everything. An unclassified collection keeps everything but noise and says so.
  • Surface (Civil 3D): lowest point per 3 ft cell, despiked, then only the key points a TIN needs within 0.1 ft - the same engine as Ground Thin.
  • Download limit: 2,000 MB (MaxDownloadMb in the settings file); tiles are cached under %LOCALAPPDATA%\VDC\LidarFetch for re-runs.

Watch out for

  • Public 3DEP lidar is mostly QL2 - about 2 points per square metre. It will NOT show curbs, gutters, narrow swales or small structures; survey those.
  • It is planning-grade terrain, not a survey - check it against field shots (VDCCLOUDQC) before design.
  • The drawing must be in NAD83 State Plane coordinates and the zone must be right, or the points land in the wrong place.
  • Not every area is in the public bucket (Horry County, SC is not) - then download LAZ tiles from the National Map and use VDCGROUNDTHIN.
  • The collection year is the flight year - new construction since then is not in it.

Related: Ground Thin (Lidar to Ground Shots) · Cloud Classify (Filter or Classify a LAS or LAZ Cloud) · Cloud Check (LAS / LAZ Doctor) · Terrain (USGS 3DEP Surface)