
Park County Lake Quality
Colorado, 11 lakes, average grade C (Fair)
Park County holds 11 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 2 of those lakes carry an A–F grade. The county-level summary describes that subset, not every water body listed. Park County averages to a C. The distribution behind that average matters more than the letter: a few stressed lakes versus many decent ones can produce the same average as the inverse.
The county's lakes lean shallow, which makes the grades sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest lake on the books is Antero Reservoir (C); the most-stressed is Elevenmile Reservoir (D).
Where to stay near Park County
Top-rated places to stay near Park County
Prices for Sep 4–6, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip to Park County?
Get lake water-quality report cards plus the best cabin & lodging deals near Park County — straight to your inbox. No spam, unsubscribe anytime.
Quick Answers for Park County
Planning a trip? Check special fishing regulations for Antero Reservoir — or check the official Colorado fishing regulations.
All Lakes in Park County
11 lakes · 2 graded, 9 not rated2 graded lakes · 9 not rated, hidden
| # | Lake | Grade | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|---|
| 1 | CAntero ReservoirPark | C | 14.8 ft | 15 µg/L | 1.1 µg/L | No recent samples | Not recorded |
| 2 | DElevenmile ReservoirPark | D | 13.1 ft | 33 µg/L | 5.5 µg/L | No recent samples | ✓ Public |
| NRMontgomery ReservoirPark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRJefferson LakePark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRLininger LakePark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRTarryall ReservoirPark | NR | No recent samples | No recent samples | No recent samples | No recent samples | ✓ Public | |
| NRMilligan LakesPark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRComo LakePark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRSpinney Mountain ReservoirPark | NR | No recent samples | No recent samples | No recent samples | No recent samples | ✓ Public | |
| NRLake GeorgePark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| NRBayou Salado ReservoirPark | NR | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded |
NR = not rated: there is not enough recent sampling to support a letter. That is EPA Integrated Reporting Category 3 (insufficient information), not a failing grade. How grading works.
Lake Match
Which lake suits how you actually use one?
Six questions — swimming, fishing, quiet, cabins, drive time — and a shortlist of graded lakes that fit, with the water quality behind each one.
Other Counties in Colorado
See how Park County stacks up in the national county water-quality rankings, or browse the full directory of graded lakes across all United States (49 states), Canada (Ontario and Québec), and 38 other country hubs..
Source: EPA National Aquatic Resource Surveys, 2026.