--- title: "Grapevine Water Hardness and Your Pool: 2024 Report Numbers" description: "What the City of Grapevine's 2024 water quality report says about hardness, alkalinity and pH, and how those numbers relate to your pool. As of October 2026." url: https://marinapool.multisites.ai/post/grapevine-water-hardness-pool publisher: Marina Pool Services phone: +1-817-896-1120 quote: https://marinapool.multisites.ai/contact --- # Grapevine Water Hardness and Your Pool: 2024 Report Numbers Grapevine'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. Local: GrapevinePublished October 21, 20264 min read Grapevine water hardness is 117 ppm for city water and 135 ppm for Trinity River Authority (TRA) water, according to the City of Grapevine’s 2024 annual water quality report. As of October 2026, that is the latest report on the city’s water quality page. Here is what the numbers say and how a pool owner can use them. ## What does Grapevine’s water quality report say about hardness? The report lists **total hardness as CaCO3** at 117 ppm for Grapevine water and 135 ppm for TRA water. One grain per gallon equals 17.1 ppm. By that calculation, 117 ppm is about 6.8 grains per gallon and 135 ppm is about 7.9. The report mixes two supplies. Grapevine treats water from Lake Grapevine and also buys water from TRA. TRA uses surface water from Lake Arlington, which is fed by Cedar Creek Reservoir and Richland-Chambers Reservoir. Reading (2024) Grapevine water TRA water Total hardness as CaCO3 117 ppm 135 ppm Total alkalinity as CaCO3 115 ppm 105 ppm pH 7.0 to 7.9 7.0 to 9.1 Total dissolved solids 256 ppm 250 ppm Calcium not listed 45.3 ppm The report also lists chloramines as the disinfectant. The annual average was 2.55 ppm, with a range of 0.5 to 4.0 ppm. ## Is that the same as my pool’s calcium hardness? No. Tap water numbers describe water in the city system. Your pool is a different thing. Water leaves a pool by evaporation, but the minerals stay behind. Each top-off then adds a little more. Over time, the pool can read very differently from the tap. [Calcium hardness](https://marinapool.multisites.ai/glossary/calcium-hardness) is the pool test that matters. The city report can tell you what you are adding when you fill. It cannot tell you what is already in the pool. ## How do I read ppm and grains per gallon? The report states that ppm means parts per million, the same as milligrams per liter. Water softener ads and some pool charts use grains per gallon instead. One grain per gallon equals 17.1 ppm, so divide the ppm figure by 17.1 to convert. Those conversions are calculations and not city figures. Use ppm when you compare the report with a pool test, since most pool test kits report calcium hardness in ppm. ## What can mineral-rich water do to tile, heaters and salt cells? Minerals can build up as [scale](https://marinapool.multisites.ai/glossary/scale) on tile, inside a pool heater and on a [salt cell](https://marinapool.multisites.ai/glossary/salt-cell). Whether that happens depends on the whole balance, not on hardness alone. pH, total alkalinity, calcium hardness and water temperature all play a part. The [Langelier saturation index](https://marinapool.multisites.ai/glossary/langelier-saturation-index) combines them into one number. Here is a simple way to think about it: Pool part What to watch Waterline tile White or gray crust that does not wipe off Heater Slow heating or a heater that shuts off Salt cell A scale warning from the salt system Plaster Rough spots on the surface None of these signs prove a hardness problem. They are reasons to run a full water test. Our [pool water chemistry chart](https://marinapool.multisites.ai/guides/pool-water-chemistry-chart) lists the readings to check. If you run a salt pool, the [saltwater vs chlorine guide](https://marinapool.multisites.ai/guides/saltwater-vs-chlorine-pool-texas) explains the extra upkeep. ## How should I use the report when I fill or top off my pool? Use it as a guide for what goes in, then test the pool. The report is a yearly summary, so a single day can differ. Marina Pool Services weekly service covers water balance, including chlorine, pH, alkalinity, calcium hardness and conditioner, plus salt if your pool has a salt system. Read more on the [weekly pool service page](https://marinapool.multisites.ai/pool-service-grapevine-tx). Steps to follow when you fill: 1. Test your pool before you add water. 2. Add water slowly and avoid overfilling. 3. Test again after the water settles. 4. Compare the new readings with your last test. 5. Ask a pro before you drain a large part of the pool. A partial drain and refill can lower mineral levels, but it also costs water and can stress a pool. Local watering rules may apply, so check the city’s water conservation page first. ## Where can I read the report myself? The City of Grapevine posts the report on its [water quality page](https://www.grapevinetexas.gov/528/Water-Quality-Report). Look at the secondary constituents table near the end. It holds hardness, alkalinity, pH and dissolved solids. City reports change each year, so check the date on the version you open. For more on pool care across the area, see our North Texas pool care guide and our [Grapevine service page](https://marinapool.multisites.ai/service-areas/pool-repair-grapevine-tx). ## Next step If your tile is crusty, your heater is slow or your salt system shows a scale warning, a water test is the place to start. 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 ### Is Grapevine water hard? The 2024 City of Grapevine report lists total hardness of 117 ppm for city water and 135 ppm for Trinity River Authority water. That is about 6.8 and 7.9 grains per gallon by calculation. The report does not call the water hard or soft. It only gives the numbers. ### Does Grapevine tap water set my pool's calcium hardness? No. Tap water is only the starting point. Evaporation removes water and leaves minerals behind, and each top-off adds more. Chemicals and plaster also change the reading. The only way to know your pool's calcium hardness is to test the pool water. ### Where does Grapevine get its water? The 2024 report says Grapevine uses surface water from Lake Grapevine and buys water from the Trinity River Authority. TRA water comes from Lake Arlington, which is fed by Cedar Creek Reservoir and Richland-Chambers Reservoir. ### Does Grapevine use chloramines? Yes. The 2024 report lists chloramines as the disinfectant, with an annual average of 2.55 ppm and a range of 0.5 to 4.0 ppm. This is a drinking water disinfectant, and it is not a pool chlorine reading. ## Pool terms on this page - [Langelier Saturation Index](https://marinapool.multisites.ai/glossary/langelier-saturation-index) - [Partial drain and refill](https://marinapool.multisites.ai/glossary/partial-drain-and-refill) - [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) - [Waterline tile](https://marinapool.multisites.ai/glossary/waterline-tile) - [Water balance](https://marinapool.multisites.ai/glossary/water-balance) - [Pool heater](https://marinapool.multisites.ai/glossary/pool-heater) - [Salt cell](https://marinapool.multisites.ai/glossary/salt-cell) ## Sources 1. [City of Grapevine: 2024 Annual Drinking Water Quality Report](https://www.grapevinetexas.gov/528/Water-Quality-Report) 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) - [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) - [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) - [Southlake Water Report in Plain English for Pool OwnersSouthlake 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.](https://marinapool.multisites.ai/post/southlake-water-report-pool-owners) - [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) ## 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)