Lake Level Almanac
Every tracker tells you the level.
None of them tells you if it is normal.
At 3,521.43 ft, Lake Powell is lower than it has been on this date in 64 years of daily record.
That sentence took 64 years of daily readings to write, and you will not find it on any other site. Not on the agency page the number comes from, not on a tracker, not in the search result you arrived from. The elevation is free everywhere. The context is nowhere.
Instant download · no account, no password · 60-day refund, no questions
What you get
One ZIP per lake. Open the HTML file in any browser. It works offline, on a phone, and it never calls out to anything. The CSVs beside it are the receipts.
Where today sits
Today’s reading ranked against every reading within a week of the same calendar date, across the whole record. The answer is a percentile and a plain sentence, not a chart you have to interpret.
The normal band
All 366 days of the year, showing the 10th to 90th percentile the lake usually occupies, with this year drawn over the top. You can see a drought arriving months before a headline does.
Your elevation
Type in your ramp, your dock, your boat lift, or the shallow spot you would rather not find. You get the number of days in the record the lake sat below it, the share of each month it did, the last date it happened, and the longest unbroken run.
The annual cycle
Which month this lake typically peaks, which month it bottoms out, the median swing between the two, and the worst swing on record. This is the number that decides when to book a trip.
Year by year
The high and the low of every calendar year with the exact dates. The whole drought history of the lake on one page.
The record itself
Every daily reading as CSV, with the datum, the parameter code, the statistic and the agency qualifier on every row. Yours to do anything with.
Unusual right now
Recomputed on every build. These are the three lakes furthest from their own normal for today’s date.
| Lake | Today | Median for the date | Percentile | Record |
|---|---|---|---|---|
| Lake Powell, UT | 3,521.43 ft | 3,634.33 ft | 2nd | 64 yr |
| Lake Allatoona, GA | 840.99 ft | 839.47 ft | 96th | 22 yr |
| Canyon Lake, TX | 910.19 ft | 906.69 ft | 91st | 31 yr |
Pick your lake
Choose one and the checkout knows which almanac to send. Deeper records make better normals, so the years column is worth a look before you buy.
| Lake | Record | Daily readings | Today | Normal for the date | |
|---|---|---|---|---|---|
| Cachuma Lake, CA | 20 yr from 2007 | 6,962 | 746.74 ft | above normal | $19 |
| Canyon Lake, TX | 31 yr from 1992 | 10,246 | 910.19 ft | far above normal | $19 |
| Don Pedro Reservoir, CA | 42 yr from 1985 | 11,894 | 802.18 ft | normal | $19 |
| Folsom Lake, CA | 42 yr from 1985 | 14,209 | 428.78 ft | normal | $19 |
| Lake Allatoona, GA | 22 yr from 1989 | 7,672 | 840.99 ft | far above normal | $19 |
| Lake Belton, TX | 27 yr from 2000 | 9,316 | 594.49 ft | above normal | $19 |
| Lake Berryessa, CA | 42 yr from 1985 | 11,299 | 432.12 ft | normal | $19 |
| Lake Fork Reservoir, TX | 31 yr from 1994 | 10,163 | 399.89 ft | below normal | $19 |
| Lake Isabella, CA | 42 yr from 1985 | 13,286 | 2,566.89 ft | normal | $19 |
| Lake Oroville, CA | 42 yr from 1985 | 14,287 | 825.73 ft | normal | $19 |
| Lake Powell, UT | 64 yr from 1963 | 22,868 | 3,521.43 ft | lowest in the whole record | $19 |
| Lake Somerville, TX | 27 yr from 2000 | 9,257 | 238.36 ft | normal | $19 |
| Lake Whitney, TX | 27 yr from 2000 | 9,411 | 532.64 ft | above normal | $19 |
| Medina Lake, TX | 29 yr from 1997 | 9,838 | 1,021.82 ft | normal | $19 |
| Millerton Lake, CA | 40 yr from 1985 | 11,838 | 518.40 ft | normal | $19 |
| New Melones Lake, CA | 42 yr from 1985 | 14,148 | 1,013.78 ft | normal | $19 |
| Pine Flat Lake, CA | 41 yr from 1985 | 13,451 | 777.40 ft | normal | $19 |
| San Luis Reservoir, CA | 39 yr from 1988 | 13,551 | 467.74 ft | above normal | $19 |
| Shasta Lake, CA | 41 yr from 1985 | 14,161 | 1,005.88 ft | normal | $19 |
Why you should believe the numbers
Nobody has bought this yet, so there are no reviews to show you and it would be worth nothing if there were. Here is what can be checked instead.
- Every reading is federal or state public-domain data, named to the gage. USGS Water Services, California’s Data Exchange Center, and Reclamation’s hydrodata for Lake Powell, whose record runs back to December 1963 while its USGS gage only starts in 2019.
- The README in every download says what was thrown away. Raw feeds carry sentinel values and bad rows. The count discarded, the reason, and the rule are printed for each lake. A product that hides its cleaning is asking you to trust an invisible step.
- Lakes that could not be done honestly are missing. Lake Mead, Lake Havasu and Lake Mohave are not here, because Reclamation’s public feed for them carries only a rolling few days and no long daily record could be assembled without guessing. Lake Buchanan is missing because its USGS gage publishes no daily-values series at all.
- The method is not invented here. Day-of-year percentiles are how the USGS itself reports streamflow on its national WaterWatch map. That map excludes stage-only gages, which is exactly what a reservoir-elevation gage is. The technique is standard; the application to reservoir levels is what nobody had done.
What this will not do
It reports what the water has done. It does not tell you whether a boat ramp is open, whether a dock will float, or whether it is safe to launch. Closures follow elevation, but they also follow staffing, silt, maintenance, and through 2025 and 2026 in California, invasive-mussel inspections that closed ramps at lakes which were not low.
That is why the elevation tool takes a threshold from you rather than asserting one. You bring the number you have verified; the almanac tells you what the water did against it. Always confirm current conditions with the operating agency before you tow anything.
Questions
At 3,521.43 ft, Lake Powell is lower than it has been on this date in 64 years of daily record.
You can go and check that against the gage yourself. Working out what it means took 22,868 readings and a lot of arithmetic. That is what the $19 buys.