Sinkhole risk in Mellette County, SD: Not karst, but voids possible
Not karst, but voids possible
No soluble bedrock; some pseudokarst (piping or lava-tube ground).
- On soluble rock
- 0%
- At or near the surface
- 0%
- Buried under cover
- 0%
What to do about a house in Mellette County
Not true karst, but soil piping or lava tubes can still open voids - mention it to an inspector.
Across 1,307 square miles, under one square mile of Mellette County maps onto soluble rock. With about 1,834 residents (1 per square mile), much of the land is open, and the mapped rock may sit far from where people actually live. The figures come from 318 map points about 2.0 miles apart, so a pocket smaller than that can be missed or overstated.
Read next: how ground with no limestone still opens up, and how these percentages are measured.
Counties around Mellette County
The nearest county rated sinkhole country is Boyd County, NE, about 110 miles southeast. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.
- Jones County, SD 26 mi north · 0% at surface
- Todd County, SD 26 mi south · 0% at surface
- Jackson County, SD 44 mi west · 0% at surface
- Tripp County, SD 47 mi east · 3% at surface
- Lyman County, SD 50 mi northeast · 0% at surface
- Bennett County, SD 54 mi southwest · 0% at surface
Against the rest of South Dakota
Mellette County ranks 50 of 66 in South Dakota for soluble rock at the surface, and sits above 0% of US counties on that measure.
- Lawrence County 42%
- Fall River County 37%
- Custer County 30%
- Gregory County 17%
- Pennington County 13%