Total Dissolved Solids

A single number for how much mineral load the water carries.

What it is

Total dissolved solids (TDS) is the sum of everything dissolved in the water, mainly minerals, salts, and metals. It is the simplest proxy for how "mineral-rich" a spring is.

In hot springs

Hot springs commonly range from roughly 200 mg/L to over 2,000 mg/L. Higher TDS means more mineralized water. Very high-TDS water can taste metallic or bitter (if ingested) and leave a faint residue on the skin.

Cited benefits and context

The WHO reports that drinking water below 600 mg/L TDS is generally of good palatability, while levels above 1,000 mg/L become increasingly poor in taste, and above 1,200 mg/L increasingly objectionable (WHO Guidelines for drinking-water quality, 4th ed.). These are ingestion standards, not soaking limits.

For soaking, high-TDS mineral water is the foundation of balneotherapy. Systematic reviews conclude balneotherapy may be associated with improvement in some rheumatological and dermatological conditions, though the quality of evidence is mixed and not strong enough for firm conclusions (PMC7383020; BMJ Open 2025 systematic review). TDS itself is not a therapeutic agent; it is an indicator of the mineral load that defines a mineral spring.

Cautions

TDS does not tell you which minerals are present. Two springs with identical TDS can have very different chemistry and very different effects.

Springs ranked by most mineral-rich (by tds)

176 springs with verified total dissolved solids data · showing top 50 · source: USGS Water Quality Portal

  1. 1

    Squaw Hot Springs

    id · 102°F · primitive

    13700 mg/L

  2. 2

    Battle Creek Hot Springs

    id · 102°F · primitive

    9830 mg/L

  3. 3

    Alpine Warm Spring

    id · 85°F · primitive

    6430 mg/L

  4. 4

    Heise Hot Springs

    id · 102°F · developed

    5940 mg/L

  5. 5

    Brockman Creek Hot Spring

    id · 102°F · primitive

    5680 mg/L

  6. 6

    Malad Warm Spring

    id · 90°F · primitive

    4350 mg/L

  7. 7

    The Landusky Plunge

    mt · 77°F · primitive

    4100 mg/L

  8. 8

    Prices Warm Spring

    id · 85°F · primitive

    3860 mg/L

  9. 9

    Woodruff Hot Spring

    id · 102°F · primitive

    3090 mg/L

  10. 10

    Big Spring

    id · 85°F · primitive

    2240 mg/L

  11. 11

    Hot Springs State Park

    wy · 104°F · primitive

    1910 mg/L

  12. 12

    Maple Grove Hot Springs

    id · 102°F · primitive

    1900 mg/L

  13. 13

    BLM Well (Frazier Hot Spring)

    id · 105°F · primitive

    1640 mg/L

  14. 14

    Bear Lake Hot Springs

    id · 102°F · developed

    1560 mg/L

  15. 15

    White Licks Hot Spring

    id · 102°F · primitive

    1440 mg/L

  16. 16

    Cleveland Hot Springs

    id · 102°F · primitive

    1350 mg/L

  17. 17

    Bald Mountain Hot Springs

    id · 115°F · primitive

    1260 mg/L

  18. 18

    Pleasantview Warm Springs

    id · 85°F · primitive

    1220 mg/L

  19. 19

    Cove Creek Hot Spring

    id · 102°F · primitive

    1140 mg/L

  20. 20

    Crane Creek Hot Springs

    id · 102°F · primitive

    1080 mg/L

  21. 21

    Alkali Flats Warm Spring

    id · 85°F · primitive

    1040 mg/L

  22. 22

    Mammoth Hot Springs

    wy · 162°F · developed

    1030 mg/L

  23. 23

    Lava Hot Springs

    id · 130°F · developed

    962 mg/L

  24. 24

    Deer Hot Springs

    id · 102°F · primitive

    885 mg/L

  25. 25

    Grape Creek Warm Spring

    id · 85°F · primitive

    857 mg/L

  26. 26

    Sharkey Hot Spring

    mt · 102°F · primitive

    839 mg/L

  27. 27

    Goldbug Hot Springs

    id · 136°F · primitive

    836 mg/L

  28. 28

    Rock Creek Hot Springs

    mt · 112°F · primitive

    826 mg/L

  29. 29

    Big Creek Hot Springs

    mt · 102°F · primitive

    725 mg/L

  30. 30

    Yandell Springs

    id · 102°F · primitive

    715 mg/L

  31. 31

    Lakey Hot Spring

    id · 102°F · primitive

    667 mg/L

  32. 32

    Sullivan Hot Springs

    id · 102°F · primitive

    640 mg/L

  33. 33

    Beardsley Hot Springs

    id · 102°F · primitive

    639 mg/L

  34. 34

    Indian Springs (Resort)

    id · 102°F · developed

    600 mg/L

  35. 35

    Pincock (Green Canyon) Hot Springs

    id · 102°F · primitive

    596 mg/L

  36. 36

    Rockland Warm Springs

    id · 85°F · primitive

    576 mg/L

  37. 37

    Roystone Hot Springs

    id · 105°F · developed

    573 mg/L

  38. 38

    Riggins Hot Springs

    id · 102°F · primitive

    566 mg/L

  39. 39

    Yellowstone Hot Springs

    mt · 104°F · resort

    553 mg/L

  40. 40

    Little Antelope Flat Warm Spring

    id · 85°F · primitive

    504 mg/L

  41. 41

    Owen Cabin Hot Spring

    id · 102°F · primitive

    493 mg/L

  42. 42

    Warm Springs

    id · 85°F · primitive

    482 mg/L

  43. 43

    Krigbaum Hot Springs

    id · 102°F · primitive

    468 mg/L

  44. 44

    Stinky Warm Spring

    id · 85°F · primitive

    464 mg/L

  45. 45

    West Pass Hot Spring

    id · 102°F · primitive

    456 mg/L

  46. 46

    Boulder Hot Springs

    mt · 102°F · resort

    443 mg/L

  47. 47

    Salmon Falls Hot Spring

    id · 102°F · primitive

    434 mg/L

  48. 48

    Firehole Lake

    wy · 160°F · developed

    424 mg/L

  49. 49

    Boulder Creek Spring

    id · 102°F · primitive

    409 mg/L

  50. 50

    Marsh Gully Hot Springs

    id · 102°F · primitive

    401 mg/L

Sources

← All minerals