Texas City Water Hardness Rankings

PickMyTapWater compiled public water system data to rank the water hardness of 35 major Texas cities. We measure hardness in Grains Per Gallon (GPG). 1 GPG equals 17.1 mg/L of calcium carbonate.

Key Findings

West Texas Dominance: Odessa, Midland, Amarillo, and Lubbock have the hardest water in the state, all exceeding 18 GPG.
San Antonio Outlier: San Antonio is the largest city in the top 5, with exceptionally hard water (17.5 GPG) sourced from the Edwards Aquifer.
The I-35 Divide: Austin (11.2) and Dallas/Fort Worth (~10) have moderately hard to very hard water, while Houston (8.5) is notably softer.
The Softest: East Texas cities like Beaumont and Tyler feature the softest water in our sample.

Rank	City	Population	Hardness (GPG)	Category
1	Odessa	114,428	19.8	Extremely Hard
2	Midland	132,524	19.5	Extremely Hard
3	Amarillo	200,393	18.5	Extremely Hard
4	Lubbock	260,993	18.2	Extremely Hard
5	San Antonio	1,434,625	17.5	Extremely Hard
6	New Braunfels	98,824	16.8	Extremely Hard
7	Abilene	125,182	16.4	Extremely Hard
8	El Paso	678,815	15.8	Extremely Hard
9	Wichita Falls	102,352	15.2	Extremely Hard
10	Sugar Land	111,026	14.5	Extremely Hard
11	Laredo	255,205	13.5	Very Hard
12	Corpus Christi	317,863	13.2	Very Hard
13	McAllen	143,920	12.8	Very Hard
14	Round Rock	119,468	12.5	Very Hard
15	Killeen	153,095	11.8	Very Hard
16	Pearland	125,828	11.5	Very Hard
17	Austin	961,855	11.2	Very Hard
18	Waco	138,486	11.2	Very Hard
19	Denton	139,814	10.8	Very Hard
20	Fort Worth	956,709	10.4	Very Hard
21	Arlington	394,266	10.2	Very Hard
22	McKinney	195,308	9.9	Hard
23	Dallas	1,304,379	9.8	Hard
24	Frisco	200,509	9.8	Hard
25	Allen	106,874	9.7	Hard
26	Garland	239,928	9.6	Hard
27	Plano	285,494	9.5	Hard
28	Irving	256,684	9.4	Hard
29	League City	114,392	9.2	Hard
30	Pasadena	151,950	8.8	Hard
31	Houston	2,304,580	8.5	Hard
32	Conroe	98,081	6.2	Moderately Hard
33	College Station	120,511	5.5	Moderately Hard
34	Tyler	105,995	4.2	Moderately Hard
35	Beaumont	115,281	3.5	Slightly Hard

Methodology: Data extracted from EPA SDWIS and local reports as of August 2026. Ranked descending by GPG, tie-broken by population served. Not a complete list of all TX public water systems.