New Mexico reservoir · state assessment record
Santa Cruz Lake
Assessment decisions reported by New Mexico to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2026 reporting cycle.
- 93
- Assessed acres
- Reservoir
- Water type
This waterbody in one line
Santa Cruz Lake, a reservoir in New Mexico, is assessed as not supporting one or more designated uses, with 3 listed impairment causes in the state's most recent Integrated Report cycle (2026). By assessed acreage it sits above the national median by assessed acreage (38,628 lakes); its impairment list is among the longest nationally (3 listed causes vs 23,610 assessed lakes). New Mexico rules it not supporting for high quality coldwater aquatic life, while other aquatic-life uses are supported.
- Not Supporting
- overall status
- P68
- Assessed size nationally
- P5
- Shorter cause list
- Not Supporting
- aquatic-life or related
Assessment verdicts are the state agency's decisions as reported to EPA ATTAINS; PlainLakes renders them without modification.
A composite of this record's EPA ATTAINS designated-use verdicts, filed impairment count, and assessment currency, weighted and benchmarked against the national corpus of assessed active waterbodies. This is a water-quality standing, not a human-recreation or property-value judgment, and dimensions with no filed verdict drop out rather than count against the score.
How Santa Cruz Lake reads against the filed register
Paragraphs are selected by this unit's percentiles and use matrix: different lakes lead with different dimensions. Figures are ATTAINS / portal register arithmetic, not advice.
The signature stat: in-state cause rank
Inside New Mexico, cause-list rank is the local separator: Santa Cruz Lake is 5 of 58 indexed units by listed-cause count, toward the top of that state's filed lists.
Mixed use determinations
This record splits: Not Supporting on aquatic life, Fully Supporting on recreation. The divergence is inside the designated-use matrix, not a single all-or-nothing label.
Longer than most cause lists
3 listed causes puts this unit above 90% of assessed lake-type records by list length. Treat that as a coding-and-sampling signal: states that split pollutants finely mint longer lists without proving worse water.
Santa Cruz Lake: Category 4A reading
Category 4A means a TMDL (or equivalent) is already approved for the impairment on Santa Cruz Lake. The remaining work is implementation and tracking, read the cleanup-standing and cause rows for what the state already committed to address.
Overall status: not supporting
The filer's overall status for Santa Cruz Lake is Not Supporting. That tile summarizes the assessment unit; the designated-use rows and cause list are the evidence behind it.
According to the U.S. Environmental Protection Agency's ATTAINS program, New Mexico carries 176 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Santa Cruz Lake without modification. See our methodology for reporting-unit limits and gauge linking rules.
The record
Designated-use assessments
Fully Supporting and Not Supporting are the state's definitive verdicts; other entries mean the use was not conclusively assessed in this cycle.
| Designated use | Group | Verdict |
|---|---|---|
| Domestic Water Supply | Drinking-water supply designation | Fully Supporting |
| High Quality Coldwater Aquatic Life | Aquatic-life or related | Not Supporting |
| Irrigation | Other | Fully Supporting |
| Livestock Watering | Other | Fully Supporting |
| Primary Contact | Recreation | Fully Supporting |
| Wildlife Habitat | Aquatic-life or related | Fully Supporting |
The record
Listed impairment causes
Causes the state listed as impairing designated uses of this reservoir, with the cycle each was first listed and the Clean Water Act action recorded against it.
| Cause | Affected uses | First listed | Cleanup standing |
|---|---|---|---|
| Temperature | High Quality Coldwater Aquatic Life | 2012 | TMDL approved |
| Aluminum, Total | High Quality Coldwater Aquatic Life | 2020 | TMDL approved |
| Nutrients | High Quality Coldwater Aquatic Life | 2020 | TMDL approved |
Probable sources named by the state
Each source below is listed under the cause the state filed it against, and carries the word the state filed with it — confirmed, or suspected.
- Temperature
- Other Recreational Pollution Sources (suspected) Impervious Surface/Parking Lot Runoff (suspected) Wastes From Pets (suspected) Silviculture Harvesting (suspected) Rangeland Grazing (suspected) Site Clearance (Land Development or Redevelopment) (suspected) Wildlife Other Than Waterfowl (suspected) Rural (Residential Areas) (suspected) Illegal Dumps or Other Inappropriate Waste Disposal (suspected) Highway/Road/Bridge Runoff (Non-Construction Related) (suspected) On-Site Treatment Systems (Septic Systems and Similar Decentralized Systems) (suspected) Silviculture, Fire Suppression (suspected)
- Aluminum, Total
- Other Recreational Pollution Sources (suspected) Impervious Surface/Parking Lot Runoff (suspected) Wastes From Pets (suspected) Silviculture Harvesting (suspected) Rangeland Grazing (suspected) Site Clearance (Land Development or Redevelopment) (suspected) Wildlife Other Than Waterfowl (suspected) Rural (Residential Areas) (suspected) Illegal Dumps or Other Inappropriate Waste Disposal (suspected) Highway/Road/Bridge Runoff (Non-Construction Related) (suspected) On-Site Treatment Systems (Septic Systems and Similar Decentralized Systems) (suspected) Silviculture, Fire Suppression (suspected)
- Nutrients
- Other Recreational Pollution Sources (suspected) Impervious Surface/Parking Lot Runoff (suspected) Wastes From Pets (suspected) Silviculture Harvesting (suspected) Rangeland Grazing (suspected) Site Clearance (Land Development or Redevelopment) (suspected) Wildlife Other Than Waterfowl (suspected) Rural (Residential Areas) (suspected) Illegal Dumps or Other Inappropriate Waste Disposal (suspected) Highway/Road/Bridge Runoff (Non-Construction Related) (suspected) On-Site Treatment Systems (Septic Systems and Similar Decentralized Systems) (suspected) Silviculture, Fire Suppression (suspected)
Reading the record
Santa Cruz Lake: Category 4A reading
4A Category 4A: impaired, TMDL completed
New Mexico filed this assessment unit as Category 4A: impaired, with a pollutant-budget TMDL already completed under 303(d). The listing remains an impairment finding; the plan is on file rather than still awaiting write-up.
Scale and rank
Santa Cruz Lake is one of 176 lake-type waterbodies reported to EPA from New Mexico, and one of 58 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 93 assessed acres it ranks 12,288th by assessed size among the 38,628 lakes the dataset carries an area for, counting a state’s repeated filings of one water once, behind 12,287 lakes with a larger one.
Open in the register
The state has not yet filed a definitive fish-consumption verdict for this record; that field populates when it reports it in a future Integrated Report cycle.
In context
Where Santa Cruz Lake sits nationally
Assessed size among U.S. lakes
Distribution of assessed acreage across ATTAINS lakes filed with an area, counting a state’s repeated filings of one water once
93 Top 32% larger than 68% of 38,628 lakes
lakes the dataset carries an area for, counting a state’s repeated filings of one water once, bucketed by value
Source EPA ATTAINS · Reporting cycles 1987–2026
Listed causes vs waterbodies carrying a verdict
How many impairment causes U.S. waterbodies with a reported verdict carry
3 Longer than most more listed causes than 90% of 23,610 waterbodies carrying a verdict
named waterbodies carrying a verdict, bucketed by value
Source EPA ATTAINS · Reporting cycles 1987–2026
In both charts each bar is a band and taller bars hold more waterbodies; the dashed line and filled bar mark Santa Cruz Lake. Hover or tap any bar for its full count and share.
In context
New Mexico context
ATTAINS carries 176 lake-type waterbodies in New Mexico, 46 assessed as not supporting at least one use and 28 fully supporting. Among the 58 indexed units there, Santa Cruz Lake ranks 5th by listed-cause count (3 listed causes) and 28th by assessed size among the 58 with an area filed; it sits in the not-supporting set (46 statewide) . Its listed causes include Temperature and Nutrients, which also appear among New Mexico's most-filed impairment causes (led by Nutrients). It also lists Aluminum, Total, outside that top-five list.
| Other large assessed lakes in New Mexico | Assessed acres |
|---|---|
| Navajo Reservoir Not Supporting | 12,680 |
| Elephant Butte Reservoir Not Supporting | 10,909 |
| South Lordsburg Playa Not Assessed | 7,412 |
| Ute Reservoir Not Supporting | 5,988 |
| Heron Reservoir Not Supporting | 4,497 |
| Laguna del Pero Fully Supporting | 4,477 |
Peers near Santa Cruz Lake's size or cause load
Similar assessed acres
Nearest filed extents (93 acres here).
- Mustinka River Flowage · 93 acres · MN
- Tucker Pond · 93 acres · RI
- Sawyer Lake · 93 acres · FL
- Norway (West Bay) · 93 acres · MN
Similar cause load
Nearest listed-cause counts (3 here). Peers already in the acreage column are omitted.
- 67th St. Beach · 3 causes · IL
- Absecon Creek (AC Reserviors) (gage to SB) · 3 causes · NJ
- Absecon Creek (below gage) · 3 causes · NJ
- Agate Reservoir · 3 causes · OR
What to do with this record
- Assessment verdicts are cycle-based, not real-time. For fish-consumption decisions, your state advisory program is the binding source. Consumption status guide
- Impairment listings follow the Clean Water Act 303(d) process; a listing is a regulatory finding, not a closure notice. 303(d) explained
PlainLakes renders state assessment decisions and federal gauge observations without modification. It does not issue advisories.
Assessment decisions on this page are rendered directly from state Integrated Report records in EPA's ATTAINS system; gauge figures are daily-value observations from the USGS National Water Information System, no number is typed in by an editor. Overall status, use verdicts, and causes are the state's reported decisions for assessment unit NM-2118.B_00. Counts and percentiles are computed across all lake-type records PlainLakes ingests from ATTAINS. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-08-17. Primary sources: EPA ATTAINS and USGS National Water Information System.