--- title: "Southlake Water Report in Plain English for Pool Owners" description: "Southlake buys water from Fort Worth. See the hardness, pH and alkalinity ranges in two city reports and how they relate to your pool, as of October 2026." url: https://marinapool.multisites.ai/post/southlake-water-report-pool-owners publisher: Marina Pool Services phone: +1-817-896-1120 quote: https://marinapool.multisites.ai/contact --- # Southlake Water Report in Plain English for Pool Owners Southlake buys all of its water from Fort Worth. Southlake's 2023 report lists total hardness of 100 to 171 ppm. Fort Worth's 2025 report lists 108 to 150 ppm. Those are tap water ranges, not pool readings, so test your pool water itself. Figures are as of October 2026. Local: SouthlakePublished October 21, 20263 min read Southlake water hardness ranges from 100 to 171 ppm in the city’s 2023 report, and from 108 to 150 ppm in Fort Worth’s 2025 report. Southlake buys all of its water from Fort Worth. This post reads both reports for pool owners. Figures are as of October 2026. ## Where does Southlake’s water come from? Southlake’s 2023 report says the city gets all its water from the City of Fort Worth. Fort Worth draws from surface water: Lake Worth, Eagle Mountain Lake, Lake Bridgeport, Richland Chambers Reservoir, Cedar Creek Reservoir and the Clear Fork Trinity River. Fort Worth’s 2025 report says it adds monochloramines (chlorine and ammonia) to protect the water as it travels through the pipes. That is a drinking water treatment. It is not a pool chlorine reading. ## What do the reports say about hardness, pH and alkalinity? The two reports list a similar set of numbers. Southlake’s 2023 report holds 2022 data. Fort Worth’s 2025 report holds 2025 data. Southlake’s water page also lists a newer Southlake report that this post does not use. Reading Southlake 2023 report Fort Worth 2025 report Total hardness as CaCO3 100 to 171 ppm 108 to 150 ppm Hardness in grains 6 to 10 grains per gallon 6 to 9 grains per gallon pH 8.1 to 8.5 7.8 to 8.5 Total alkalinity as CaCO3 90.4 to 144 ppm 99.7 to 124 ppm Total dissolved solids 161 to 278 ppm 182 to 244 ppm Calcium 33.6 to 51.9 ppm 37.6 to 48.1 ppm Both reports give ranges, not one number. The tap water at your house depends on the day and on which part of the system serves you. ## Why does a tap water range matter for a pool? Water leaves a pool through [evaporation](https://marinapool.multisites.ai/glossary/evaporation-loss) and the minerals stay behind. Each top-off adds more. So a pool can drift far from the tap numbers in a season. Three readings matter most when you fill: 1. [Calcium hardness](https://marinapool.multisites.ai/glossary/calcium-hardness): the mineral level that affects plaster and equipment. 2. [pH](https://marinapool.multisites.ai/glossary/ph): both reports show tap water pH of 7.8 or higher, so a pH check after a fill makes sense. 3. Total alkalinity: it steadies pH, so it moves with every fill. The [water balance](https://marinapool.multisites.ai/glossary/water-balance) of your pool is the full picture. Our [pool water chemistry chart](https://marinapool.multisites.ai/guides/pool-water-chemistry-chart) lists each reading and why it matters. ## How do I read the ranges? Each range runs from the lowest to the highest result in that report year. Southlake’s report lists 2022 data and Fort Worth’s lists 2025 data, so the two ranges are not from the same year. They still agree on the main point: Fort Worth water is in the same band of roughly 6 to 10 grains per gallon. A single test at your tap can land anywhere inside that range. ## What should Southlake pool owners do with this? Treat the reports as a guide and your pool test as the answer. Keep a short routine: When What to do Before you top off Test calcium hardness, pH and alkalinity After a large fill Test again once the water has mixed Each season Compare your readings with the last season If you see crust or rough plaster Run a full test and ask a pro Marina Pool Services weekly service covers water balance, including calcium hardness and conditioner, and empties baskets and backwashes filters as needed. See the [weekly pool service page](https://marinapool.multisites.ai/pool-service-grapevine-tx) for details. ## Where can I read the reports? Southlake posts its reports on the [city water quality page](https://www.cityofsouthlake.com/4162/Water-Quality). Fort Worth posts its 2025 report on the [Fort Worth water quality page](https://www.fortworthtexas.gov/departments/water/water-quality). Open the secondary constituents table, which holds hardness, pH and alkalinity. Reports change each year, so check the date on the version you read. For wider advice, read our [North Texas pool care guide](https://marinapool.multisites.ai/guides/north-texas-pool-care) or see our [Southlake service page](https://marinapool.multisites.ai/service-areas/pool-repair-southlake-tx). ## Next step If you want a second set of eyes on your water balance, see our [pool maintenance services](https://marinapool.multisites.ai/our-services/pool-maintenance-services). Call (817) 896-1120 or use the quote form at [/contact](https://marinapool.multisites.ai/contact). ## Frequently asked questions ### Where does Southlake get its water? Southlake's 2023 water quality report says the city gets all of its water from the City of Fort Worth. Fort Worth draws from Lake Worth, Eagle Mountain Lake, Lake Bridgeport, Richland Chambers Reservoir, Cedar Creek Reservoir and the Clear Fork Trinity River. ### How hard is Southlake tap water? Southlake's 2023 report lists total hardness of 100 to 171 ppm, or 6 to 10 grains per gallon. Fort Worth's 2025 report lists 108 to 150 ppm, or 6 to 9 grains per gallon. The range is wide because the number changes over the year. ### Can I use the city report as my pool test? No. The report describes water in the city system. A pool changes as water evaporates and minerals stay behind. Test the pool water for calcium hardness, pH and alkalinity, and use the city report only as a reference for what you add when you fill. ## Pool terms on this page - [Total dissolved solids](https://marinapool.multisites.ai/glossary/total-dissolved-solids) - [Weekly pool service](https://marinapool.multisites.ai/glossary/weekly-pool-service) - [Calcium hardness](https://marinapool.multisites.ai/glossary/calcium-hardness) - [Total alkalinity](https://marinapool.multisites.ai/glossary/total-alkalinity) - [Water balance](https://marinapool.multisites.ai/glossary/water-balance) - [Plaster](https://marinapool.multisites.ai/glossary/plaster) ## Sources 1. [City of Southlake: 2023 Water Quality Report](https://www.cityofsouthlake.com/DocumentCenter/View/44321/2023-Water-Quality-Report) 2. [City of Southlake: Water Quality](https://www.cityofsouthlake.com/4162/Water-Quality) 3. [City of Fort Worth: Water Quality Reports (2025 report)](https://www.fortworthtexas.gov/departments/water/water-quality) Written by Marina Pool Services and checked against the sources above on October 21, 2026. City rules and product guidance change, so check the linked page before you act. Follow product labels for any pool chemical. ## Keep reading - [Pool Water Chemistry Chart and What Each Number MeansMost home pools run free chlorine of 1 to 3 ppm, pH of 7.2 to 7.8, total alkalinity of 80 to 120 ppm and calcium hardness of 200 to 400 ppm. CDC sets the health floor at pH 7.0 to 7.8 and at least 1 ppm chlorine. Your equipment manual may narrow these ranges.](https://marinapool.multisites.ai/guides/pool-water-chemistry-chart) - [North Texas Pool Care: Heat, Storms, Pollen, and Hard WaterNorth Texas pools face triple-digit heat, spring pollen, sudden storms, and mineral-rich water. Heat and sunlight use up chlorine, storms add debris and nutrients, and evaporation leaves minerals behind. Weekly testing, a clean filter, and steady pump run time keep most pools clear. Marina Pool Services offers weekly service in Grapevine.](https://marinapool.multisites.ai/guides/north-texas-pool-care) - [Keller Water Report: What It Means for Pool ChemistryKeller buys its water from Fort Worth. Keller's 2024 report lists total hardness of 76.5 to 175 ppm, about 5 to 10 grains per gallon. Fort Worth's 2025 report lists 108 to 150 ppm. These are tap water ranges, so test your pool water for its own readings. Figures are as of October 2026.](https://marinapool.multisites.ai/post/keller-water-report-pool-chemistry) - [Grapevine Water Hardness and Your Pool: 2024 Report NumbersGrapevine's 2024 water quality report lists total hardness of 117 ppm for city water and 135 ppm for Trinity River Authority water, about 6.8 and 7.9 grains per gallon. Those are tap water numbers. Your pool reading will differ, so test the pool itself. Figures are as of October 2026.](https://marinapool.multisites.ai/post/grapevine-water-hardness-pool) - [Saltwater vs Chlorine Pools in TexasA saltwater pool still uses chlorine. A salt cell makes it from dissolved salt instead of you adding it. That means steadier chlorine and less handling of chemicals, but more equipment to maintain, a salt cell that wears out, and pH that tends to drift up. Neither option is maintenance free.](https://marinapool.multisites.ai/guides/saltwater-vs-chlorine-pool-texas) - [Hard Water and Calcium Scale on Pool Tile in Tarrant CountyScale is calcium that comes out of the water and sticks to tile, surfaces and equipment. City water reports list hardness of 117 and 135 ppm in Grapevine (2024), 110 ppm in Colleyville (2025) and 76.5 to 175 ppm in Keller (2024). Swim University says to keep pool calcium hardness at 175 to 275 ppm.](https://marinapool.multisites.ai/post/hard-water-calcium-scale-pool-tile-tarrant) ## Need a hand with your pool? Call or text and tell us what your pool needs. Estimates are free for qualifying services, and same-day estimates are possible when the schedule allows. [Call (817) 896-1120](tel:+1-817-896-1120)[Get a quote](https://marinapool.multisites.ai/contact) ![A pool technician working on an equipment pad](https://marinapool.multisites.ai/_astro/technician-equipment-pad.BW5xZMNY_Zum1K5.webp)