Oregon Elevation ToolsOpen Route Explorer on the map →

Lines · Tap two endpoints

Farm road and driveway route planner by grade

This farm road grade planner finds a route between two points that favors gentle grades and stays under the maximum grade you set, then shows its elevation profile. It switchbacks up a face the way a road designer would, using the USGS 3DEP lidar model.

Use it to test whether a grade limit can be met at all, and to sketch where a road or driveway could go before walking it with a contractor.

Free to run · pay to download

See the full result on the map free, with no account. Download the route as GeoJSON and its profile as CSV with a pass: US$29 for 24 hours, US$99 for 30 days or US$399 for 12 months, a one-off payment in US dollars that never renews. Every download on the site is included while the pass lasts.

Open Route Explorer on the map →Pass prices and what’s included

Who uses this

  • Farmers, ranchers and foresters. Sketch a road line that equipment can use.
  • Rural landowners. Test whether a driveway to the house site can make the grade.

When to use it

  • Sketching where a farm road, a driveway or a trail could go on a hillside.
  • Checking whether a grade limit can be met at all between two points.

Tools for your job

Route Explorer is one step in a bigger question. These are the jobs it helps with, and the tools that go with it.

For the job: Excavation, driveways and farm roads

How much digging, and can a driveway or farm road make the grade?

  1. 1.Cut & Fill — Cut and fill in cubic yards to level a pad, at an elevation you set or the one that balances.
  2. 2.Elevation Profile — Grade along a proposed driveway, section by section.
  3. 3.Route Explorer (this tool) — Finds a line between two points that stays under a maximum grade.
  4. 4.Contour Lines — Site contours at 1 or 2 ft to hand to a designer.

How to use it

  1. Open Route Explorer and tap the start and the end.
  2. Set the maximum route grade in percent.
  3. Finish the endpoints and run. The route is drawn, and the profile appears in the panel.
  4. Export the route as GeoJSON and the profile as CSV.

Step by step: Mount Hood

We ask for a route from the lodge up the slope that never gets steeper than 20%.

1.Open Route Explorer, tap the start and the end, and confirm the endpoints. Set the maximum grade.

2.Run the analysis. Instead of the straight line, the route switchbacks up the slope; the panel gives the length, total climb and the steepest section.

What it showed

  • Lower the grade limit and the route gets longer. If no route fits, the profile shows where the limit is broken.
Try it yourself on Mount Hood →

How it works

Terrain is loaded for the two endpoints plus a 0.31 mi margin. Every cell is a node connected to its eight neighbors, with a cost that grows with distance and with grade, and a very high cost above your limit. The lowest-cost path from start to end is found, which is why the route switchbacks up a face rather than going straight.

Reading the results

The profile shows the grade the route actually achieves. If parts still exceed your limit, no route within the margin could avoid them.

Length and total climb are along the route, not the straight line.

Limits and caveats

  • A terrain exploration aid, not a road design. Cut and fill, drainage, culverts, sight distances and legal access are not considered.
  • The search is limited to 0.31 mi either side of the endpoints, so a route that needs a wide detour will not be found.
  • Where lidar has not been flown, the USGS 3DEP model falls back to its 1/3 arc-second layer, about 33 ft per pixel, and downloads state what share of the area came from it. That coarser model is not fit for site-scale decisions. DOGAMI reports about 99% of Oregon covered by at least one lidar project. The fallback is rare.

Data and attribution

Results come from the USGS 3D Elevation Program (3DEP) bare-earth elevation model: lidar at 3.3 ft per pixel where it has been flown, and the 1/3 arc-second model, about 33 ft per pixel, elsewhere, with elevations above NAVD 88. The tools with a surface option (Sunlight, Viewshed, Sightline, Object Heights) read DOGAMI’s statewide digital surface model of trees and buildings.

USGS 3DEP elevation data and USGS maps are U.S. Government works in the public domain: you may use the results, including commercially. A credit to the USGS 3D Elevation Program is appreciated, and every file you download carries it. DOGAMI lidar products are published by the State of Oregon; credit "DOGAMI / Oregon Lidar Consortium". County taxlot boundaries are the assessor's GIS data, not surveys, and each county publishes its own disclaimer, shown with the parcel. The aerial basemap is from Esri and follows Esri's terms; it is not included in downloads.

Questions

Is this a road design?

No. It is a terrain exploration aid. Cut and fill, drainage, culverts, sight distances and legal access are not considered.

Ready to try it?

Open Route Explorer on the map →

Free to use, no account. The analysis runs in your browser on public-domain USGS 3DEP data. Downloading the results needs a pass: see pricing.