If Southlake's water rates went up 15% on October 1, why will most households see a smaller jump on the combined bill that arrives in November? And why will the households that kept their sprinklers on a summer schedule through October see a jump that comes closer to the full number?
Water and sewer went up by different amounts, and they stop counting at different points. Sewer charges stop rising at 10,000 gallons, and water tiers keep climbing past 40,000. So the more of your October use went to the lawn, the closer your increase gets to the full 15%.
Two Rate Sheets, Side by Side
The City of Southlake's September 4 notice on My Southlake News gave the headline numbers. Water rates went up 15% to pass through higher costs from the City of Fort Worth, which sells Southlake its treated water. Sewer went up 5% to pass through costs from the Trinity River Authority, which treats Southlake's wastewater. The new water and sewer rates apply to usage starting October 1 and first appear on November bills. The trash and recycling change came sooner: it rose $0.58 to $21.46 a month and already showed up on October bills.
The details are in the published tariffs. Compare the rate sheet effective October 1, 2025 with the rate sheet effective October 1, 2026 and the changes for a residential 1-inch meter look like this:
| Residential charge, 1-inch meter | FY2026 | FY2027 | Change |
|---|---|---|---|
| Water, first 2,000 gallons, fixed | $44.00 | $50.60 | +$6.60 |
| Water, 2,001 to 10,000, per 1,000 gal | $4.92 | $5.66 | +$0.74 |
| Water, 10,001 to 25,000, per 1,000 gal | $5.65 | $6.50 | +$0.85 |
| Water, 25,001 to 40,000, per 1,000 gal | $6.50 | $7.48 | +$0.98 |
| Water, above 40,000, per 1,000 gal | $7.47 | $8.59 | +$1.12 |
| Sewer, first 2,000 gallons, fixed | $44.98 | $47.23 | +$2.25 |
| Sewer, 2,001 to 10,000, per 1,000 gal | $6.60 | $6.93 | +$0.33 |
| Sewer, maximum residential charge | $97.78 | $102.67 | +$4.89 |
Two things in that table drive everything after it. Every water tier went up by the same 15%, so the steps between tiers kept their shape. And the sewer maximum works out to exactly 10,000 gallons: the $47.23 base plus eight more thousand-gallon blocks at $6.93 comes to $102.67. Past 10,000 gallons, a household's sewer charge stops rising for the month.
For homes on a 2-inch residential meter, the fixed water charge covers the first 7,000 gallons. That charge went from $136.30 to $156.75, so it rises $20.45 a month before any extra gallons are counted. The flat $8.00 storm water charge did not change.
The Same 15%, Four Different Bills
Run a few monthly usage levels through both rate sheets and the combined water-and-sewer increase lands well below 15% for most of them. It is smallest right around the sewer cap and grows from there.
The figures below are illustrative. They come straight from the published tiers for a 1-inch residential meter and leave out trash, sales tax, and storm water.
| Monthly use | FY2026 water + sewer | FY2027 water + sewer | Increase | Increase in % |
|---|---|---|---|---|
| 2,000 gallons | $88.98 | $97.83 | +$8.85 | about 9.9% |
| 10,000 gallons | $181.14 | $198.55 | +$17.41 | about 9.6% |
| 30,000 gallons | $298.39 | $333.45 | +$35.06 | about 11.7% |
| 50,000 gallons | $438.09 | $494.15 | +$56.06 | about 12.8% |
At 10,000 gallons or less, the 5% sewer increase holds the combined number down, because sewer makes up more than half the bill. Above 10,000 gallons, sewer is capped and every additional thousand gallons goes onto the water side of the bill, which rose 15%. The more gallons a household uses, the more of its bill is water, and the closer its combined increase gets to the full 15%.
The cap also flips which gallons are expensive. After the fixed charges for the first 2,000 gallons, each thousand gallons from 2,001 to 10,000 costs $5.66 for water plus $6.93 for sewer, or $12.59 combined. Above 40,000 gallons, each thousand costs $8.59, all of it water. Per gallon, a heavy irrigation month is billed at a lower combined rate than the gallons between 2,001 and 10,000. It is also where the dollar increase grows fastest, because those gallons are priced only on the water side.
October Is the Month That Sets It
The new water rates apply from October 1, so the first bill priced under them is mostly a record of how often the sprinklers ran during October.
The watering schedule in the city's water conservation ordinance on Municode was adopted under Ordinance 895-C in 2014 and remains in effect:
- Residential addresses ending in an even number may water on Wednesdays and Saturdays.
- Residential addresses ending in an odd number may water on Thursdays and Sundays.
- Watering is allowed between midnight and 10 a.m. and between 6 p.m. and midnight, so sprinklers cannot run from 10 a.m. to 6 p.m.
- Hand watering, drip irrigation, and soaker hoses are exempt from the assigned days.
Fort Worth follows the same twice-weekly pattern and the same 10 a.m. to 6 p.m. limit for its own water customers, according to the City of Fort Worth's irrigation page. Southlake appears on Fort Worth's list of wholesale customers.
The ordinance sets the most you can water. It doesn't say how much a lawn needs in late October. Southlake's February 2026 irrigation guidelines note that the city requires rain and freeze sensors on irrigation systems under Ordinance 895-A, and they include a checklist for adjusting controller programs by season. Two regional sources address the cooler months directly:
- The Water is Awesome North Texas watering guide, from the Tarrant Regional Water District, calls for watering once a week if a lawn needs a little water, twice if the weather is hot and dry, and not at all if it has rained or rain is in the forecast. Its weekly watering advice adjusts that recommendation using recent rainfall. Southlake's city site links to that weekly advice.
- Texas A&M AgriLife's bermudagrass calendar says dormant bermudagrass should not be irrigated in late fall, winter, or early spring. It recommends turning irrigation off or cutting it back significantly from late fall to early spring.
On the rate table, this decides which tier a household ends up in. A controller still running a summer program through October can push that month's bill into the 25,001-gallon and 40,001-gallon tiers. A controller cut back to the Water is Awesome guidance keeps more of the month in the lower tiers, where sewer makes up a larger share of the bill and the 5% increase pulls the combined percentage down.
The city's View Your Water Usage page is the place to check how much you have used so far. Watering days and rate tiers come from city ordinance and the adopted rate schedule. This post is general information, not legal or financial advice, so confirm your own account details and any rule questions with Southlake Water Utilities.
Where the 15% Comes From
The city's notice calls most of these increases pass-throughs from regional partners. It attributes Fort Worth's higher charges to rising water supply and operating costs plus ongoing investment in the regional water system. The 15% is Southlake's retail pass-through of those costs to its customers.
The costs start further upstream. The Fort Worth Report covered the Tarrant Regional Water District board's vote raising its 2027 raw-water charge from $1.43 to $1.50 per 1,000 gallons. The outlet tied the change to rising demand and the funding needed for aging infrastructure. That is a raw-water charge, which is a separate layer from the treated-water rate Fort Worth bills Southlake. Together they show that the cost of water is rising at more than one point before it reaches a Southlake meter.
The trash increase has a different cause. The city says it comes from the five-year agreement with Community Waste Disposal and reflects changes in fuel, disposal, and other operating costs. The $21.46 monthly rate also covers twice-weekly bundled brush pickup, monthly household hazardous waste and electronics collection, two extra leaf recycling days a year, and one free cart cleaning a year.
Southlake Water Utilities Customer Service is also moving. My Southlake News reported that the new Municipal Service Center at 1605 Brumlow Avenue is expected to be finished in early 2027. Customer Service will move there along with the Water, Wastewater, Streets & Drainage, and Environmental Services teams.
Lawn, irrigation, and carrying costs come up in nearly every Southlake conversation we have with clients, from deciding whether a large lot fits a family's routine to estimating what a home costs to run month to month. If you would like a clearer picture of ownership costs in Southlake, Holly Davis & Amy Farris are glad to go through them with you. Contact Us.
