New Hampshire Soil Drainage Rankings
How well does the soil drain across New Hampshire? We ranked every USDA survey area by the percentage of land classified as "well drained." Areas at the top of the list have soils where water moves through at a healthy rate — favorable for building, septic, and gardening. Areas at the bottom have more waterlogged or slowly-draining soils that may require engineered solutions.
The best-drained survey area is Hillsborough County, New Hampshire, Western Part at 70% well-drained soils. The most drainage-challenged is Strafford County, New Hampshire at 36%.
stays wet (poorly drained)in between, or not ratedwell drained
| # | Survey Area | Land by drainage | Well Drained | Poorly Drained | Most common class |
|---|---|---|---|---|---|
| 1 | Hillsborough County, New Hampshire, Western Part | 70% | 11% | Well drained | |
| 2 | Cheshire County, New Hampshire | 64% | 10% | Well drained | |
| 3 | Grafton County, New Hampshire | 64% | 7% | Well drained | |
| 4 | Sullivan County, New Hampshire | 64% | 9% | Well drained | |
| 5 | Hillsborough County, New Hampshire, Eastern Part | 56% | 11% | Well drained | |
| 6 | Merrimack and Belknap Counties, New Hampshire | 52% | 15% | Well drained | |
| 7 | Rockingham County, New Hampshire | 50% | 24% | Well drained | |
| 8 | Coos County Area, New Hampshire | 50% | 18% | Well drained | |
| 9 | Carroll County Area, New Hampshire | 48% | 11% | Well drained | |
| 10 | Strafford County, New Hampshire | 36% | 18% | Well drained |