A buyer who closes on a Castle Rock home this October gets keys and a garage door opener. They don't get the seller's water budget. Castle Rock Water bills each household against a budget built from that household's own use. When the account changes names, the budget the seller built over years of winters goes with them.
The timing makes this matter. The months Castle Rock Water uses to set a customer's indoor allowance run from November through February. A fall buyer moves in just as that window opens.
The budget is attached to the account, not the house
Castle Rock Water charges for actual monthly use, measured against tiers for indoor use, outdoor irrigation, use over budget and a surcharge above 40,000 gallons. The utility's billing FAQ says those tiers "are established by your household's actual usage and are independent of your neighbors."
Tier 1 is the Average Winter Monthly Consumption, which the 2026 rate schedule defines as the average of a customer's potable water use from November through February. It is reset every year on April statements. The same figure stands for the amount of wastewater treated each month, so one winter average sets both the indoor water tier and the wastewater volume.
New customers start somewhere else. The schedule says that "until an individual AWMC is established, an average for the customer class is assigned for both water and wastewater." That means the seller's past bills describe the seller's household: how many showers, which appliances, whether anyone traveled over the holidays. They show what the home's fixed charges look like. They say much less about what a different household's indoor tier will turn out to be.
The second tier covers seasonal irrigation from April through October. Castle Rock Water's published materials describe it as an irrigation allocation. They don't lay out a household-level formula, so the details of any one property's outdoor budget are a question for the utility directly.
How a fall closing lines up with the averaging window
The rate schedule's own dates show how the first year of ownership plays out for a buyer closing in October 2026:
- October: The account opens under the new owner's name. Castle Rock Water lists a Water Service Transfer Fee of $36 among its 2026 administrative fees. October use is still billed at irrigation-season rates, which apply to consumption from April 1 through October 31.
- November through February: These are the averaging months. Use during this stretch is what the winter average is built from, and winter-season rates apply to consumption from November 1 through March 31.
- April statements: Castle Rock Water resets winter averages each year on April statements.
- May through November bills: Irrigation-season consumption shows up on these bills, with Tier 2 in effect.
Exactly when a new account moves from the class average to its own figure follows Castle Rock Water's standard operating procedures, which the schedule references but doesn't spell out. The structure is still clear. Indoor tiers come from winter months, and the first winter after a fall closing is the new household's first chance to create its own record.
Before a single gallon, the bill starts at $65.23
The volumetric side of the bill depends on the household. The fixed side doesn't. On a standard 5/8-by-3/4-inch residential meter, 2026 monthly fixed charges look like this:
| 2026 monthly fixed charge | Amount |
|---|---|
| Water service | $11.49 |
| Renewable water resource | $36.30 |
| Wastewater | $8.65 |
| Stormwater | $8.79 |
| Total before any usage | $65.23 |
Compare that with what a typical household uses in winter. Mark Henderson, assistant director at Castle Rock Water, told Denver7 in March 2026:
"The average winter usage for our average customer is about 5,000 gallons per month, but during the summer it goes up to 15,000 gallons per month."
At the 2026 Tier 1 rate of $3.39 per 1,000 gallons, 5,000 gallons of water comes to $16.95 on the water volumetric line. Wastewater volume is billed on top of that, but in a typical winter month the fixed charges are clearly the bigger share. The renewable water resource charge alone is more than double that water line.
The tiers step up quickly in summer. In 2026, residential irrigation-season rates are $3.39 for Tier 1, $6.91 for Tier 2 and $10.31 for use over budget, with another $10.31 per 1,000 gallons for use above 40,000 gallons in a month. In winter, use over the indoor budget is billed at $6.91.
The fixed charges are what keep rising
The renewable water charge has been climbing faster than the volumetric rates. Town Council passed Ordinance 2025-033 on first reading October 7, 2025, by a 7–0 vote and adopted it October 21, 2025, by a 6–0 vote, with the new rates effective January 1, 2026. It moved standard residential volumetric rates from $3.23, $6.58 and $9.82 to $3.39, $6.91 and $10.31. It also raised the monthly water resource charge on a standard meter from $33.61 to $36.30. The Town's rate study puts the 2026 increases at 5% for water, 8% for water resources, 5% for stormwater and 0.5% for wastewater, or 4.57% overall.
The 2027 package follows the same pattern, but it's still a proposal. A staff report dated September 15, 2026, proposes 5% increases to water rates, 8% to the water resources fixed charge, 5% to stormwater and 1% to wastewater. Under that proposal, monthly fixed charges on a residential 3/4-inch meter would go from $65.23 to $69.23. A typical annual bill would go from $1,571 to $1,647, an increase of $76.
Staff also proposed replacing the single surcharge above 40,000 gallons with three bands for 2027: $10.83 per 1,000 gallons from 41,000 to 50,000 gallons, $21.66 from 51,000 to 100,000, and $32.49 above 100,000. The report says 208 customers would have reached the higher bands if those charges had applied in 2026.
Ordinance 2026-037 was on Council's October 6, 2026, agenda for first reading. As of October 7, the Town's record lists the ordinance's status as "Second Reading" with October 6 as the final-action date, but the result field reads "Not available." Staff had proposed considering it on October 6 and October 20. Until a final vote is recorded, the 2027 figures are proposals.
New construction: fees set by floor area, front yards set by code
On new homes, the water story moves from the monthly bill to the price of the home. Until July 1, 2026, a home counted as one single-family equivalent carried a renewable water fee of $35,829, a water system development fee of $9,931 and a wastewater system development fee of $6,130. Council passed Ordinance 2026-014 on first reading April 21, 2026, 6–0, and on final reading May 5, 2026, 7–0. Starting July 1, it ties those three fees for new single- and two-family homes to gross floor area instead of meter size alone. Gross floor area includes basements and excludes what the ordinance calls "parking garages," along with open decks, patios and balconies.
For a new home of 2,000 to 2,499 square feet, the July 2026 schedules set the renewable water fee at $23,385.40, the water fee at $6,481.91 and the wastewater fee at $4,001.02. The proposed 2027 package would raise system development fees by 20% for water, 7.5% for water resources and 8.5% for wastewater.
The landscaping is regulated too. The Town's Landscape and Irrigation Criteria Manual, dated April 23, 2026, requires ColoradoScape design in new-home front yards. It allows larger areas of lower-water-use turf in backyards case by case and caps the water budget at the equivalent of 19 inches per season. Landscape plans must define front and back irrigable areas separately. A buyer comparing a new home with a resale down the street may be comparing two very different yards, along with two different fee histories.
Why Castle Rock prices water this way
The budget system belongs to a larger conservation effort, and 2026 tested it. Castle Rock Water declared Stage 2 drought restrictions on July 19, 2026. It returned to Stage 1 on September 1 after conservation cut daily demand by 10 to 20%. Stage 1 restored the every-third-day watering schedule, though the Town encouraged watering two days a week.
The longer trend backs up the approach. Castle Rock averaged 111 gallons per person per day in 2025, its lowest level since 2007. The ColoradoScape rebate, offered since 2009, pays $3.25 per square foot to replace conventional turf and had removed more than 1.5 million square feet of high-water-use turf by March 2026.
The rising renewable water charge pays for supply. The Town's 2026 budget planned design work on a WISE desalination facility and said Castle Rock would receive twice as much imported WISE water in 2026 as before. The 2027–2031 capital plan in the rate study includes $59.6 million for WISE desalination infrastructure. Castle Rock Water is also updating its Water Resources Strategic Master Plan and has scheduled a public open house for Thursday, October 8.
A few common questions
Do the seller's water bills tell a buyer anything? They confirm the meter's fixed charges and show how one household used water. Because each account's indoor tier comes from its own winter use, and new accounts start on a class average, past bills don't predict a new owner's tiers.
Are the 2027 rates final? Not as of October 7, 2026. Ordinance 2026-037 was on the October 6 agenda for first reading. The Town's record now lists it at second reading, but the vote result is not yet posted.
Does the July 2026 fee change affect resale homes? Ordinance 2026-014 covers renewable water, water and wastewater fees for new single- and two-family homes. Existing homes pay the monthly rates described above.
Water is one of the costs that's easy to miss when comparing Castle Rock homes, and fixed charges, fees and timing all affect what a home costs to own. If you're weighing a purchase here or getting ready to sell, Avenues Real Estate can go through the numbers with you, and you can start with a free home valuation.
This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.
