Pool swim season in Liberty Lake, WA
When can you swim in an outdoor pool in Liberty Lake, WA?
An unheated pool in Liberty Lake never reaches 78°F in a normal year. It peaks around 74°F in Aug. The air allows up to 4 swimmable months with a heater (Jun to Sep).
- J
- F
- M
- A
- M
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- J
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- S
- O
- N
- D
What each heater buys you in Liberty Lake
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 0 | no month | $0 | $0 |
| Solar cover only | 1 | Aug | $0 | $50 |
| Solar panels + cover | 4 | Jun to Sep | $0 | $283 |
| Heat pump + cover | 4 | Jun to Sep | $166 | $716 |
| Gas heater + cover | 4 | Jun to Sep | $399 | $824 |
For a 450 sq ft pool held at 80°F, at WA prices of 14.4¢/kWh electricity and $18/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Liberty Lake
Solar panels + cover: 4 of 4 possible months for about $283 a year all-in, which works out near $71 for each month it adds.
Before you pay for any heater, buy a solar cover: on its own it adds 1 month here for about $50 a year (why a cover comes first). If you get quotes, ask for a heat pump sized to your pool's surface area; here it beats gas all-in (heat pump or gas).
Weather station: Spokane Felts Field, 10.2 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Liberty Lake month by month: air, sun and pool water
| Month | Air high | Air avg | Sun kWh/m²/day | Water, unheated | Water, covered | Heat pump $ | Gas $ |
|---|---|---|---|---|---|---|---|
| Jan | 38° | 32° | 1.1 | 30° | 36° | – | – |
| Feb | 43° | 35° | 2.0 | 32° | 38° | – | – |
| Mar | 51° | 42° | 3.1 | 38° | 44° | – | – |
| Apr | 60° | 48° | 4.6 | 46° | 52° | – | – |
| May | 70° | 57° | 5.9 | 55° | 61° | – | – |
| Jun | 76° | 63° | 6.5 | 64° | 70° | $90 | $215 |
| Jul | 87° | 72° | 7.4 | 72° | 78° | $17 | $47 |
| Aug | 86° | 70° | 6.1 | 74° | 80° | – | – |
| Sep | 76° | 61° | 4.4 | 67° | 73° | $59 | $137 |
| Oct | 60° | 49° | 2.6 | 55° | 61° | – | – |
| Nov | 45° | 38° | 1.3 | 42° | 48° | – | – |
| Dec | 37° | 31° | 0.9 | 33° | 39° | – | – |
Heating costs most in Jun (about $90 with a heat pump, $215 with gas). Sunshine peaks in Jul at 7.4 kWh/m²/day (NASA satellite data, 35.1 km grid cell). Highlighted months are swimmable with no heater.
How Liberty Lake compares with nearby cities
Liberty Lake ranks 12 of 91 Washington cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Spokane Valley, WA | 6 mi | 0 | 4 | $166 |
| Post Falls, ID | 8 mi | 0 | 4 | $190 |
| Rathdrum, ID | 13 mi | 0 | 4 | $190 |
| Coeur d'Alene, ID | 15 mi | 0 | 4 | $190 |
| Spokane, WA | 15 mi | 0 | 4 | $166 |
| Hayden, ID | 16 mi | 0 | 4 | $190 |