Oligotrophic Lakes in New Mexico
4 oligotrophic lakes in New Mexico. Low nutrients, clear water, excellent for swimming.
An oligotrophic lake is what most people picture when they think of pristine northern lake country: clarity to depth, no algal scum, cold water that holds dissolved oxygen all the way to the bottom even in August. Across {{stateName}}, 4 lakes register as oligotrophic — 0% of them break 50 feet of depth, which is the structural condition that underwrites the trophic class. Without depth and a low-nutrient watershed, oligotrophy is hard to sustain.
On the LakeGrade rubric, oligotrophic lakes almost always pull an A or B — the same low-nutrient conditions that produce the trophic class also produce the high grade.
| # | Lake | County | Grade | Clarity | Depth | TSI |
|---|---|---|---|---|---|---|
| 1 | Navajo Reservoir | San Juan | A | 16 ft | - | 35 |
| 2 | Nla Lake | San Juan | A | 14.4 ft | - | 34 |
| 3 | Navajo Reservoir la Jara Confluence | Rio Arriba | A | 13.5 ft | - | 37 |
| 4 | Lea Lake Overflow | Chaves | A | - | - | 40 |
Source: EPA National Aquatic Resource Surveys, 2026.