Connecticut lake · state assessment record
Crystal Lake (Middletown)
Assessment decisions reported by Connecticut to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2014 reporting cycle.
- 31
- Assessed acres
- Lake, Freshwater
- Water type
This waterbody in one line
Crystal Lake (Middletown), a lake in Connecticut, is assessed as not supporting one or more designated uses, with one listed impairment cause in the state's most recent Integrated Report cycle (2014). By assessed acreage it sits below the national median by assessed acreage (38,628 lakes); its impairment list is among the longest nationally (one listed cause vs 23,610 assessed lakes).
- Not Supporting
- overall status
- P43
- Assessed size nationally
- P20
- Shorter cause list
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.
Reading Crystal Lake (Middletown)'s filed record
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 Connecticut, cause-list rank 36 of 97 is mid-pack, the state peer table is not driven by an extreme list length here.
No ruled-on use clears the bar
On the uses this filer ruled on, recreation, every determination is Not Supporting. That is a use-by-use reading of the filed record, not a single overall lake grade.
Crystal Lake (Middletown): Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Crystal Lake (Middletown). Read the listed causes and any cleanup actions filed beside them before treating the overall status tile as a finished restoration story.
Overall status: not supporting
The filer's overall status for Crystal Lake (Middletown) is Not Supporting. That tile summarizes the assessment unit; the designated-use rows and cause list are the evidence behind it.
Small within Connecticut
State size rank 78 of 97 puts Crystal Lake (Middletown) toward the small end of Connecticut's indexed lake-type units with an area.
According to the U.S. Environmental Protection Agency's ATTAINS program, Connecticut carries 182 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Crystal Lake (Middletown) 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. Connecticut filed its own confidence on the one definitive verdict it rated: Good. That rating is the filer's, in EPA's own field, and EPA publishes no definition of the four words it offers.
| Designated use | Group | Verdict |
|---|---|---|
| Recreation | Recreation | Not Supporting Filer confidence: Good |
| Fish Consumption | Fish-consumption or fishery | Insufficient Information Filer confidence: Good on other public health indicators; Excellent on physical/chemical |
| Habitat for Fish, Other Aquatic Life and Wildlife | Aquatic-life or related | Insufficient Information |
The record
Listed impairment causes
Causes the state listed as impairing designated uses of this lake, with the cycle each was first listed and the Clean Water Act action recorded against it.
| Cause | Affected uses | First listed | Cleanup standing |
|---|---|---|---|
| Escherichia coli (E. coli) | Recreation | 1996 | TMDL priority: High |
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.
- Escherichia coli (E. coli)
- Unspecified Urban Stormwater (suspected) Waterfowl (suspected)
Connecticut also recorded the source of at least one listing here as unknown, including for Escherichia coli (E. coli).
Reading the record
Cleanup queue for Crystal Lake (Middletown)
1 listed cause ranked High in the TMDL queue, still without a plan
Connecticut ranked Escherichia coli (E. coli) high in its TMDL development queue, and no cleanup plan is on file for that listing yet. That queue rank is the state's own scheduling signal, not an EPA national rule.
A High ranking names a position in the state's plan-writing queue; it is not a measure of how impaired the water is. How listing and cleanup work.
Scale and rank
Crystal Lake (Middletown) is one of 182 lake-type waterbodies reported to EPA from Connecticut, and one of 97 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 31 assessed acres it ranks 22,024th 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 22,023 lakes with a larger one.
Awaiting a filing
The state has not yet filed a definitive fish-consumption verdict and a definitive aquatic-life verdict for this record; those fields populate when it reports them in a future Integrated Report cycle.
In context
Where Crystal Lake (Middletown) 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
31 Top 57% larger than 43% 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
1 Longer than most more listed causes than 49% 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 Crystal Lake (Middletown). Hover or tap any bar for its full count and share.
In context
Connecticut context
ATTAINS carries 182 lake-type waterbodies in Connecticut, 44 assessed as not supporting at least one use and 95 fully supporting. Among the 97 indexed units there, Crystal Lake (Middletown) ranks 36th by listed-cause count (one listed cause) and 78th by assessed size among the 97 with an area filed; it sits in the not-supporting set (44 statewide) . Its listed causes include Escherichia coli (E. coli), which also appears among Connecticut's most-filed impairment causes (led by Algae).
| Other large assessed lakes in Connecticut | Assessed acres |
|---|---|
| Candlewood, Lake (New Fairfield/Danbury/Sherman/New Milford) Fully Supporting | 5,086 |
| Lillinonah, Lake (Newtown/Southbury/Bridgewater/Brookfield) Not Supporting | 1,595 |
| Bantam Lake (Litchfield/Morris) Not Supporting | 955 |
| Colebrook River (Reservoir) Lake (Colebrook) Not Assessed | 852 |
| Pachaug Pond (Griswold) Fully Supporting | 837 |
| Saugatuck Reservoir (Weston/Easton/Redding) Fully Supporting | 823 |
Peers near Crystal Lake (Middletown)'s size or cause load
Similar assessed acres
Nearest filed extents (31 acres here).
- Dummer · 31 acres · MN
- Priest Lake · 31 acres · WI
- Haig Pond (Hsighs)-02050106002565 · 31 acres · PA
- Mulehead Pond · 31 acres · FL
Similar cause load
Nearest listed-cause counts (1 here). Peers already in the acreage column are omitted.
- Aaron · 1 causes · MN
- Aaron River Reservoir · 1 causes · MA
- Abbotts Creek (including Lexington-Thomasville Water Supply Reservoir at normal reservoir elevation, Tom-A-Lex Lake) · 1 causes · NC
- Abeniki Lake · 1 causes · NH
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 CT4013-05-1-L1_01. 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.