Grindstone Caynon Reservoir Inlet
Lincoln County, New Mexico39 acresView mapDirections
Nutrients and algae run above the regional average.
- Eutrophic
- Impaired · Temperature
- #3 of 3 in the county
- Limited data
Grindstone Caynon Reservoir Inlet in Lincoln County, New Mexico has a water quality grade of D (Nutrient-rich). Phosphorus: 61 µg/L. Surface area: 38.8 acres.
- Area
- 39 acres
- Type
- Eutrophic
- Phosphorus
- 61 µg/L
- Trend
- ↑ Improving
Stays via Stay22
Stays near Grindstone Caynon Reservoir Inlet
Compare lakeside cabins, hotels, and vacation rentals near Grindstone Caynon Reservoir Inlet in Lincoln County, New Mexico — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Grindstone Caynon Reservoir Inlet are listed below.
Top-rated places to stay near Grindstone Caynon Reservoir Inlet
Prices for Sep 11–13, 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 whole trip? See where to stay at New Mexico’s top lakes →
Watch Grindstone Caynon Reservoir Inlet’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
Grindstone Caynon Reservoir Inlet is a 39-acre productive, nutrient-rich eutrophic lake in Lincoln County, New Mexico. Water quality is graded D based on 1 sampling years through 2024. Overall water quality is improving over recent sampling years. Compared to the 2 other monitored lakes in Lincoln County, Grindstone Caynon Reservoir Inlet ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, NMED, last sampled 2024-09-26. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The D is nutrients and algae, not a swimming clearance. Grindstone Caynon Reservoir Inlet is listed impaired under Clean Water Act §303(d) (IR 5) for temperature. Check local advisories before you swim.
Water Quality Grade: D (Nutrient-rich)
No clarity data. Phosphorus 61 µg/L. TSI 63. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 61 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 63 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 39 acres |
No bathymetric survey has been published for Grindstone Caynon Reservoir Inlet, so its depth is not documented here.
Fishing Grindstone Caynon Reservoir Inlet
Water Quality Trend: ↑ Improving
Based on 3 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.171 m/yr | 3 |
Reservoir Info (USACE NID)
Grindstone Caynon Reservoir Inlet is a man-made reservoir impounded by the Grindstone Canyon Dam (completed 1987), built primarily for water supply on the Grindstone Canyon; roller-compacted concrete-type dam, 133 ft tall and 1,304 ft long.
- Surface area
- 38.8 ac
- Normal storage
- 1,549.8 ac-ft
- Max storage
- 1,700 ac-ft
- Drainage area
- 1.23 sq mi
- Hazard class
- High
- Owner
- VILLAGE OF RUIDOSO
Source: USACE National Inventory of Dams, NID ID NM00513 · Operator website · Matched by proximity (0.17 km)
EPA Impairment Status
Grindstone Caynon Reservoir Inlet is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit NM-2209.B_20 · Official waterbody report · Matched by proximity (0.29 km)
County Ranking
Ranked #3 of 3 lakes in Lincoln County
Nearby Lakes With Higher Grades
Grindstone Caynon Reservoir Inlet holds Grade D. 2 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
Nearby Lakes in Lincoln County
Frequently asked questions about Grindstone Caynon Reservoir Inlet
Where is Grindstone Caynon Reservoir Inlet?
- Grindstone Caynon Reservoir Inlet is a lake in Lincoln County, New Mexico. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Grindstone Caynon Reservoir Inlet?
- Grindstone Caynon Reservoir Inlet in Lincoln County, New Mexico has a water quality grade of D (Nutrient-rich). Phosphorus: 61 µg/L. Surface area: 38.8 acres.
Is Grindstone Caynon Reservoir Inlet safe to swim in?
- The D is nutrients and algae, not a swimming clearance. Grindstone Caynon Reservoir Inlet is listed impaired under Clean Water Act §303(d) (IR 5) for temperature. Check local advisories before you swim.
Explore Grindstone Caynon Reservoir Inlet across LakeQuality
Species activity outlook by water temperature and season
Where to stay at New Mexico's top lakes, each with its grade
High nutrients, frequent algae, reduced clarity
New Mexico's cleanest and most-polluted lakes, ranked
More New Mexico Lake Rankings
Other Grade D Lakes in New Mexico
Eutrophic Lakes in New Mexico
Where this data comes from
4 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- NM Environmental Dept./SWQB
21NMEX_WQX4 samples · 2024
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database