For most Tucson homes, filling a typical 15,000-gallon pool with city water costs somewhere around $125 to $225 in water charges, based on Tucson Water’s rates that took effect July 6, 2026. The exact number depends on how much water your household already uses that month, because Tucson Water bills single-family homes on tiers. It is a one-time cost and a small part of a pool project. After that, the ongoing water cost is mostly evaporation.
Below we walk through the math step by step so you can plug in your own pool size.
How much water does a pool hold?
It depends on the pool’s length, width and depth. Small pools and spools hold less. Big pools with deep ends hold more. Your builder should give you the exact gallons from the design. With a 3D pool design, you can know the size and depth before anyone digs.
Water bills do not use gallons, though. Tucson Water bills in CCF, which means 100 cubic feet. One CCF is about 748 gallons.
To convert: gallons ÷ 748 = CCF.
| Pool size | Approximate CCF |
|---|---|
| 10,000 gallons | 13.4 CCF |
| 15,000 gallons | 20.1 CCF |
| 20,000 gallons | 26.7 CCF |
| 25,000 gallons | 33.4 CCF |
What are Tucson Water’s current residential rates?
Tucson Water lists these single-family rates for customers inside city limits, effective July 6, 2026:
| Charge | Rate |
|---|---|
| Tier I (1 to 7 CCF per month) | $2.33 per CCF |
| Tier II (8 to 15 CCF) | $4.26 per CCF |
| Tier III (16 to 30 CCF) | $8.57 per CCF |
| Tier IV (31+ CCF) | $12.89 per CCF |
| Water Supply Fee | $1.25 per CCF |
| Conservation Fee | $0.15 per CCF |
| Green Stormwater Infrastructure (GSI) Fee | $0.15 per CCF (inside city limits only) |
| Monthly service charge, 5/8-inch meter | $20.65 |
Tucson Water customers outside city limits pay a higher price in each tier and do not pay the GSI fee. The monthly service charge is the same whether you fill a pool or not, so we leave it out of the fill math below.
These rates are the first step of the yearly increases the city approved in May 2026. We covered that decision in our news post on Tucson’s 2026 water rate increase.
How much does it cost to fill a 15,000-gallon pool in Tucson?
Here is a worked example. It is an estimate for a home inside Tucson city limits on a single-family rate. Your bill will vary.
Step 1: Convert gallons to CCF. 15,000 ÷ 748 = about 20 CCF.
Step 2: Add the per-CCF fees. The Water Supply, Conservation and GSI fees add $1.55 for every CCF. 20 × $1.55 = $31.00.
Step 3: Figure out which tiers the pool water falls into. This is where your normal household use matters. The pool water stacks on top of what you already use that month.
| Scenario | Tier charges for the 20 CCF | Plus fees | Pool fill cost |
|---|---|---|---|
| Pool is the only water used that month (rare) | 7 at $2.33 + 8 at $4.26 + 5 at $8.57 = $93.24 | $31.00 | About $124 |
| Household already used 10 CCF | 5 at $4.26 + 15 at $8.57 = $149.85 | $31.00 | About $181 |
| Household already used 15 CCF | 15 at $8.57 + 5 at $12.89 = $193.00 | $31.00 | About $224 |
The first row is a floor, not a realistic bill, since almost every home uses some water in a month. The second and third rows are closer to what most families see. A larger pool, or a high-use summer month, pushes more of the fill into the top tier.
One more wrinkle: a fill can straddle two billing periods. If part of the water lands on one bill and part on the next, more of it may fall into lower tiers.
What if I’m in Marana, Oro Valley or another water district?
Not everyone around Tucson is on Tucson Water. Marana Water and Oro Valley Water Utility both use tiered residential rates, but they bill per 1,000 gallons instead of per CCF, with their own tier breaks and base charges. Other neighborhoods are served by smaller private companies or water districts.
The method is the same everywhere. Find your tiers on your bill or your utility’s rate page, add up how much the pool water will cost in each tier, and add any per-unit fees.
When does the fill happen during a new pool build?
On a new pool, the fill comes right after the interior finish goes on. It is one of the last steps before startup, and timing matters.
Pebble Technology’s start-up instructions for its finishes call for:
- Testing the source water before the fill, so the startup chemistry can be adjusted to it.
- Filling without stopping. Stopping partway can leave a line on the new finish at that water level.
- Not filling with softened water. If your outside hose bibs are on a water softener, tell your builder before the fill.
Plan the fill with your builder ahead of time, including where the hoses go and who watches the water level. The fill usually takes a day or more with hoses, depending on water pressure and pool size. Plan on someone being home.
Should I use a water truck or a garden hose?
Most pools are filled with hoses from the house. It is simple, and the cost is just your water bill.
Water delivery trucks are another option. Here is how they compare in general terms:
| Garden hose | Water truck | |
|---|---|---|
| Cost | Your normal water rates | Usually more than tap water, priced by the load |
| Speed | Slower, often a day or more | Much faster for the delivered volume |
| Good for | Most new pools and refills | Very large pools, low water pressure, or a fill that must finish quickly |
| Watch out for | Softened water, hoses moved or kinked partway through | Water source and quality, access for a heavy truck, damage to new decking |
If you are thinking about a truck, ask the hauler where the water comes from and get a firm price. Then compare it to your tap cost using the math above. On a new build, check with your builder first, because fill water quality affects how a new finish cures.
How much water does a pool lose to evaporation in Tucson?
After the first fill, evaporation is where most of your pool’s water goes. The EPA’s WaterSense program estimates that an uncovered 500-square-foot pool can lose between 12,000 and 31,000 gallons a year to evaporation, depending on climate. It notes that heated pools lose even more, and that losses are highest in hot, dry places. That describes Tucson well.
In other words, over a year an uncovered pool can lose close to what it took to fill it. You pay for that water a little at a time as the pool tops off.
The same EPA guide says a pool losing more than about 3 inches a week in a hot, dry area probably has a leak. It describes a simple bucket test to check.
How can I cut the cost of filling and topping off a pool?
Use a pool cover
The EPA says solid, mesh or hybrid covers can cut evaporation by up to 95 percent when they are on the pool. Tucson’s 2024 pool code also requires a cover on new and remodeled pools before final inspection. See our post on Tucson’s pool cover requirement.
Size the pool for how you will use it
Surface area drives evaporation. If you mostly want to cool off and lounge, a smaller pool or spool may suit you better. Our guide to small pools and plunge pools has ideas.
Add shade and block the wind
The EPA notes that windbreaks and shade help reduce evaporation. Block walls, plantings and covered patios placed in the right spots all help. We plan these together in the design.
Keep the water balanced
Good chemistry means you should rarely, if ever, need to drain and refill. That saves water and protects your finish.
Run water features on a schedule
Waterfalls and sheer descents add turbulence, which the EPA says raises evaporation. Put them on automation so they run when you are outside.
What else should I budget for besides water?
The fill is a small line item compared with the pool itself. Most new custom pools we build run about $40,000 to $120,000 or more, depending on size, features and site. Our pool cost guide breaks down what drives the price, and our post on the yearly cost to run a pool in Tucson covers water, power, chemicals and upkeep after you swim.
Planning a pool?
We are a family-owned builder of concrete pools and spas in Tucson, licensed under AZ ROC #342505 and #352797. We design in 3D, walk you through the fill and startup, and handle the permits. Contact us or call (520) 342-8335 to talk about your project.
Sources
- City of Tucson: Your Residential Water Bill (rates effective July 6, 2026)
- City of Tucson: Water Rate and Fee Adjustments FY 2027–2030
- Town of Marana: Water Rates and Fees
- Town of Oro Valley: Water Rates 2026 (PDF)
- U.S. EPA WaterSense: Jump Into Pool Water Efficiency (PDF)
- Pebble Technology: Recommended Start-Up & Maintenance Procedures (PDF)
Put this guide to work
Planning your own project? See our Custom Pool Construction in Tucson, Plunge & Cocktail Pools in Tucson and Pool Decks: Travertine & Pavers in Tucson, or read about building a pool in Marana or Oro Valley.
Frequently asked questions
How many CCF does it take to fill a pool?
One CCF is 100 cubic feet of water, or about 748 gallons. Divide your pool's gallons by 748 to get CCF. A 15,000-gallon pool takes about 20 CCF, and a 20,000-gallon pool takes about 27 CCF.
Why does my water bill jump so much the month I fill the pool?
Tucson Water uses tiered rates for single-family homes. The more water you use in a month, the higher the price for each extra CCF. Pool water lands on top of your normal household use, so much of it is billed in the higher tiers.
Is it cheaper to use a water truck to fill a pool?
Not usually, but it can be faster. A truck delivers a big load at once, which helps when the fill must not stop. Ask the hauler where the water comes from, compare the price to your tap cost, and check with your builder first, since fill water quality matters for a new finish.
How long does it take to fill a pool with a garden hose?
It depends on your water pressure, the hose and the pool size. Many pools take a day or more with a single hose. Running more than one hose, if your builder approves, shortens the time.
Do I have to refill my pool every year?
No. With good water care, a full drain and refill should be rare. Most of the water you add after the first fill replaces evaporation. A cover is the best way to cut that loss.
Do Marana and Oro Valley charge the same as Tucson Water?
No. Marana Water and Oro Valley Water Utility set their own tiered rates, billed per 1,000 gallons instead of per CCF. Check your own utility's rate page or bill to estimate your fill cost.
