Water Quality in Allen, TX

Allen's water has very hard water (242 PPM). A water softener is recommended to protect plumbing and appliances. Read below for a full breakdown.

City of Allen · Source: Lavon Lake, Lake Texoma · Serves 105,623 residents

242
Hardness (PPM)
400
TDS (PPM)
1.6
Chlorine (mg/L)
4
PFAS (ppt)
2
Lead (ppb)
242 PPM 0 400 Very Hard
CONTAMINANT LEVELS Hardness 242 PPM TDS 400 PPM PFAS 4 ppt Lead 2 ppb Chlorine 1.6 mg/L Nitrate 2 mg/L

Hardness Scale: Where Allen Falls

Soft 060120180250400+
Very hard water

Allen receives water from the North Texas Municipal Water District. DFW metroplex water is hard from limestone bedrock.

What Allen's Water Means for Your Home

Allen residents deal with some of the hardest municipal water in the country. At 242 PPM (14.2 grains per gallon), the water contains high concentrations of dissolved calcium and magnesium picked up from the regional geology as surface water is treated and distributed. This is not a safety issue. The minerals are safe to consume. But they create real, measurable costs for homeowners. Hard water at 242 PPM costs the average household $800 to $1,200 per year in hidden expenses, including higher energy bills from scale-insulated water heaters, increased soap and detergent usage, and premature appliance failure. Many Allen homeowners discover this only after a water heater replacement or plumber visit.

Beyond hardness, Allen's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 1.6 mg/L as a disinfectant residual, which is normal for municipal water systems. If you notice a pool-like taste or experience dry skin, a whole-house carbon filter is the most common and affordable solution. For homeowners who want to understand the full picture, requesting your utility's annual Consumer Confidence Report provides neighborhood-level data.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)242 PPM< 60 PPMNo federal limit⚠ Very Hard
Total Dissolved Solids400 PPM< 300 PPM500 PPM⚠ Elevated
PFAS (total)4 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead2 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine1.6 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate2 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Allen Homes

🧂 Water Softener
At 242 PPM (14.2 GPG), Allen's water is very hard. Scale will accumulate in pipes, water heaters, and on fixtures. A salt-based ion exchange softener removes the calcium and magnesium causing the problem. For a typical Allen household of 2 to 4 people, a 48,000-grain softener is the right starting size.
Learn more about this solution →
🚿 Whole-House Carbon Filter
Chlorine measured at 1.6 mg/L. While safe to drink, this level often causes noticeable taste, odor, and can dry skin and hair. A whole-house carbon filter removes chlorine from every faucet and shower.
Learn more about this solution →

About Allen's Water Supply

Water Utility: City of Allen

Water Source: Lavon Lake, Lake Texoma

Population Served: 105,623

Hardness: 242 PPM (14.2 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by City of Allen. To get exact numbers for your address, request a copy of the most recent Consumer Confidence Report (CCR) from your utility, or have your water independently tested.

Compare Allen to Other Texas Cities

Houston

120 PPM · Hard

San Antonio

240 PPM · Very Hard

Dallas

100 PPM · Moderately Hard

Fort Worth

110 PPM · Moderately Hard

El Paso

265 PPM · Extremely Hard

Arlington

124 PPM · Hard

Frequently Asked Questions About Allen Water

Is Allen tap water safe to drink?
Allen's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. Review the contaminant table above for specific numbers and how they compare to both legal limits and health guidelines.
Do I need a water softener in Allen?
Yes. At 242 PPM (14.2 GPG), Allen's water is very hard. Without a softener, expect visible scale buildup on faucets and shower heads, reduced water heater efficiency (15 to 25 percent higher energy costs), spotted dishes and glassware, and soap that does not lather well. A salt-based water softener is the standard solution. For a typical Allen home with 2 to 4 residents, a 48,000-grain system is the most common starting size.
What water filter is best for Allen?
The best filter depends on which contaminants you want to address. For chlorine taste and odor, an activated carbon filter is effective and affordable, available as under-sink, countertop, or whole-house systems. See our softener vs. filter guide to understand the difference between these categories.
Where does Allen's water come from?
Allen's drinking water is sourced from Lavon Lake, Lake Texoma and treated by City of Allen. Allen receives water from the North Texas Municipal Water District. DFW metroplex water is hard from limestone bedrock.
What is the hardness of Allen water in grains per gallon?
Allen's water hardness is 14.2 grains per gallon (GPG), which equals 242 parts per million (PPM). This is classified as very hard. Most water softener manufacturers recommend treatment above 7 GPG. To convert: 1 GPG = 17.1 PPM.
Does Allen water damage tankless water heaters?
Yes. Most tankless water heater manufacturers recommend water hardness below 7 to 11 GPG (120 to 188 PPM). At 14.2 GPG, Allen's water exceeds this threshold. Scale buildup inside the heat exchanger reduces efficiency and can void the manufacturer's warranty. A water softener installed upstream of the tankless heater is the standard solution.
Is Allen water safe for babies and infants?
Allen's water meets all EPA safety standards and is generally considered safe for preparing infant formula. The hardness minerals (calcium and magnesium) are not harmful. If your home has older plumbing, running cold water for 30 seconds before use is a good precaution to flush any lead from pipes.
How much does hard water cost a Allen household per year?
At 242 PPM, hard water costs the average Allen household an estimated $800 to $1,200 per year in hidden costs. This includes 15 to 25 percent higher water heating bills from scale insulation, 50 to 75 percent more soap and detergent usage, shorter appliance lifespans (water heaters, dishwashers, washing machines), and increased plumbing maintenance. A water softener typically costs $600 to $1,500 installed and $50 to $100 per year in salt, which means most Allen households see a return on investment within 1 to 2 years.

Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the City of Allen Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.