Some of these decisions are EPA's. 13 of these 304 records carry a Clean Water Act cleanup plan EPA established rather than Alabama. They are counted in every figure on this page, and each record page names which.
State water-quality picture · #28 by reported lake-type waterbodies
Alabama lakes and reservoirs
Every figure on this page is computed from the assessment decisions Alabama reported to the U.S. Environmental Protection Agency under Clean Water Act sections 303(d) and 305(b) (reporting cycles 2006–2024), plus daily water-level observations from the U.S. Geological Survey.
- 304
- Reported waterbodies
- 143
- Not supporting a use
- 131
- Fish use not supporting
- 0
- Gauged lakes
Alabama in one line
304 lake-type waterbodies in Alabama are reported to EPA ATTAINS across reporting cycles 2006–2024: 143 assessed as not supporting at least one designated use, 130 fully supporting, and 31 without a definitive overall verdict. The most-listed impairment cause is Mercury, on 77 waterbodies.
- 304
- reported waterbodies
- 143
- not supporting a use
- 130
- fully supporting
- 52%
- of definitive verdicts impaired
An unassessed waterbody is neither confirmed clean nor confirmed impaired; states assess on multi-year cycles.
Alabama's mid-size register with a lighter not-supporting share
Alabama sits in the middle third by inventory size (304 units) and in the lowest third for ruled not-supporting share (52%).
Data updated 2026-08-17
According to the U.S. Environmental Protection Agency's ATTAINS program, Alabama reported 304 lake-type waterbodies in Alabama in the August 2026 extract. See our methodology for filer attribution and multi-year reporting cycles.
Overall-status mix on Alabama's mid-size inventory
Every reported lake-type unit in Alabama falls into exactly one overall-status bucket. This bar is the inventory partition; the cause chart and national gauge below answer different questions.
Most-listed impairment causes in Alabama
Waterbodies carrying each listed cause, most first
- Mercury
Mercury
77 waterbodies
- Phosphorus, Total
Phosphorus, Total
36 waterbodies
- Biochemical Oxygen Demand (BOD)
Biochemical Oxygen Demand (BOD)
32 waterbodies
- Nutrients 30
Nutrients
30 waterbodies
- Polychlorinated Biphenyls (PCBs) 26
Polychlorinated Biphenyls (PCBs)
26 waterbodies
What this shows Mercury is the most-listed impairment cause in Alabama, on 77 of the lake-type waterbodies reported there.
Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.
Alabama: 52% of ruled verdicts are not-supporting, against a national share of 53%, 1.0× below the national rate.
Reporting practice
Alabama's waterbodies mostly carry a definitive verdict
Each reporting authority decides how much of the water it files to EPA it actually assesses in a cycle. That decision sets the denominator behind every count on this page.
Alabama holds the 28th-largest reported lake-type inventory in the country, 304 assessment units, carrying a definitive verdict on 89.8% of it. The counts above describe the 273 units carrying a verdict, not all 304 reported. Alabama has also retired 12 lake-type assessment units, superseded filings that are kept on the site but not counted here.
The states reporting at the nearest rates are Maine (89.4%) and Kentucky (91.5%).
Assessing more of an inventory is a reporting choice, set by cycle length, monitoring budget and how finely a state splits its waters into units. It is not a measure of water quality, and it is why a raw count from one state does not sit beside a raw count from another. How assessment coverage varies.
Alabama against every comparable state
Share of reported lake-type waterbodies carrying a definitive verdict
89.8% 12th of 47 higher than 35 of 47 states
the 47 comparable states, by definitive-verdict share
Each bar is a band; taller bars hold more states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA ATTAINS · Reporting cycles 1987–2026
Each bar counts states whose definitive-verdict share falls in that 10-point band. The 47 states shown are those reporting at least 25 lake-type units; a share off a smaller inventory is precision the data does not have.
By size
Largest assessed lakes in Alabama
By assessed acreage as reported in ATTAINS. Acreage is the assessed unit's size, which can differ from a lake's full surface area.
| # | Waterbody | Assessed acres |
|---|---|---|
| 1 | Tennessee River (Lake Guntersville) Assessment unit AL06030001-0901-102 Fully Supporting | 20,440 |
| 2 | Wheeler Lake Assessment unit AL06030002-1107-103 Not Supporting | 18,705 |
| 3 | Tallapoosa River (Lake Martin) Fully Supporting | 15,867 |
| 4 | Coosa River (Weiss Lake) Not Supporting | 15,066 |
| 5 | Tennessee River (Wheeler Lake) Not Supporting | 13,441 |
| 6 | Tennessee River (Wilson Lake) Not Supporting | 13,363 |
| 7 | Coosa River (Logan Martin Lake) Not Supporting | 10,945 |
| 8 | Coosa River (Lay Lake) Not Supporting | 10,559 |
| 9 | Wheeler Lake Assessment unit AL06030002-1205-102 Not reported | 10,438 |
| 10 | Tennessee River (Lake Guntersville) Assessment unit AL06030001-0906-100 Fully Supporting | 10,177 |
| 11 | Chattahoochee River (Walter F. George Lake) Not Supporting | 9,797 |
| 12 | Pickwick Lake Fully Supporting | 9,485 |
By cause count
Most-listed waterbodies in Alabama
Waterbodies carrying the most listed impairment causes among the lake-type units reported by Alabama.
| # | Waterbody | Listed causes |
|---|---|---|
| 1 | Flint Creek (Wheeler Lake) Not Supporting | 6 |
| 2 | Kelly Creek (Lay Lake) Not Supporting | 5 |
| 2 | Talladega Creek (Lay Lake) Not Supporting | 5 |
| 2 | Tallaseehatchee Creek (Lay Lake) Not Supporting | 5 |
| 5 | Big Wills Creek (Neely Henry Lake) Not Supporting | 4 |
| 5 | Black Creek (Neely Henry Lake) Not Supporting | 4 |
| 5 | Coal Fire Creek (Aliceville Lake) Not Supporting | 4 |
| 5 | Coosa River (Lay Lake) Not Supporting | 4 |
| 5 | Dry Branch (Lay Lake) Not Supporting | 4 |
| 5 | Peckerwood Creek (Lay Lake) Not Supporting | 4 |
9 of the 10 rows in this table tie on the ranked value: 3 at 5 (rank 2), 6 at 4 (rank 5). Tied rows share a rank and are listed in no meaningful order; where a tie reaches the top the medal is shared, because nothing separates those rows.
States near Alabama's lighter not-supporting load
Two EPA ATTAINS peer sets outside Alabama. The reporting-practice chart above stays on definitive-verdict share; these neighborhoods highlight register-size and not-supporting peers while Alabama's ruled impairment share sits in the lowest third.
States with a similar reported inventory
Nearest states by lake-type units on the register (304 here).
- North Carolina · 299 units · 5 off
- Kansas · 328 units · 24 off
- Virginia · 275 units · 29 off
- Maine · 339 units · 35 off
Similar not-supporting load
Nearest states by units assessed not supporting a use (143 here). Inventory peers above are omitted.
- Indiana · 145 not supporting · 2 off
- South Dakota · 145 not supporting · 2 off
- Iowa · 137 not supporting · 6 off
- Missouri · 151 not supporting · 8 off
Peers are nearest-neighbor matches on EPA ATTAINS register size and not-supporting counts among states with at least 25 reported units. Impairment peers skip states already listed in the inventory column so the two link sets stay distinct.
Using this state picture
- Comparisons across states hold on shares, not counts: 89.8% of the inventory reported from Alabama carries a definitive verdict, 12th of 47 comparable states. National rankings
- Fish-consumption verdicts here are assessment decisions. Species-level meal advice comes from the state fish-advisory program. Consumption guide
- Browse every named Alabama waterbody with a populated record. Browse waterbodies
PlainLakes renders state assessment decisions and federal gauge observations without modification.
Figures on this page are computed from the assessment decisions Alabama reported to EPA's ATTAINS system and from USGS National Water Information System daily values, no number is typed in by an editor. State counts aggregate every lake-type assessment unit reported by Alabama, including unnamed units that never receive their own page. 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.