Hard Water in Mercer County, NJ: Softener, Conditioner or Nothing?
Hard water in Mercer County depends a lot on where you live and where your water comes from. Homes on private wells in the northern part of the county, around Hopewell Township, Pennington and the hills toward the Sourland Mountain, draw from fractured shale, sandstone and other bedrock, and that water is often hard. Homes in the flatter southern and eastern parts of the county, and most homes on public water, can see very different numbers. Test before you buy anything: under about 7 grains per gallon (120 mg/L) many families do fine without treatment, above about 10.5 grains (180 mg/L) a water softener usually makes a real difference in appliance life and cleaning time, and in between it comes down to what bothers you. Well owners in northern Mercer should also test for arsenic before choosing any equipment. A Clear Alternative tests Mercer County water at no charge; call 1-888-577-8088.
What Hard Water Is and How It Is Measured
Hardness is mostly dissolved calcium and magnesium picked up as groundwater moves through rock. It is not a health problem. It is a nuisance and a maintenance cost: white scale on faucets and glass shower doors, spots on dishes, soap that will not lather, and mineral buildup inside water heaters, dishwashers and boilers.
Labs usually report hardness in milligrams per liter (mg/L) as calcium carbonate. Water treatment equipment is rated in grains per gallon (gpg). To convert, divide mg/L by 17.1. The U.S. Geological Survey hardness scale groups water this way:
- Soft: 0 to 60 mg/L (about 0 to 3.5 gpg)
- Moderately hard: 61 to 120 mg/L (about 3.5 to 7 gpg)
- Hard: 121 to 180 mg/L (about 7 to 10.5 gpg)
- Very hard: more than 180 mg/L (more than 10.5 gpg)
Why Mercer County Water Varies So Much
Mercer County sits right on the line between two very different kinds of ground. The northern part of the county, including much of Hopewell Township, Hopewell Borough, Pennington and parts of Princeton and Lawrence, lies in the Piedmont, where wells are drilled into bedrock. Water that sits in fractured shale and sandstone dissolves minerals over time, and hard to very hard well water is common there.
The southern and eastern parts of the county, toward Hamilton, Robbinsville and East Windsor, sit closer to or on the sandy Coastal Plain. Groundwater there tends to be softer and more acidic, and iron is a more common complaint than hardness. Public water customers across the county may be served from different sources, so hardness can differ from one neighborhood to the next.
The point is simple: your neighbor’s result, or a county average, will not tell you what is in your water. A test will.
How to Find Out Your Hardness
If You Are on Public Water
Your water provider publishes an annual water quality report, often called a Consumer Confidence Report, and many list hardness. Call the number on your bill if it is not listed. Keep in mind that hardness can vary by season and by which source is feeding your area.
If You Are on a Private Well
Use a New Jersey certified laboratory, or have us test in your home. Ask for hardness along with pH, iron and manganese, because all four affect which equipment will work. Our guide on how to read a water analysis report walks through the results.
Test for Arsenic in Northern Mercer
This matters before you choose treatment. Hopewell Township’s homeowner’s guide to arsenic in well water notes that NJDEP recommends private well owners in the Piedmont test for arsenic, that arsenic has no taste, color or smell, and that New Jersey’s drinking water limit is 5 micrograms per liter. A softener does not remove arsenic, so if it shows up, the treatment plan changes.
Softener, Conditioner or Nothing?
When You Can Probably Skip Treatment
If your water is soft or only moderately hard, under about 7 gpg, many families live with it comfortably. Wiping down shower doors, using a rinse aid in the dishwasher and descaling the coffee maker now and then may be all you need. If you are on the line, live with it for a while and notice what bothers you.
When a Water Softener Makes Sense
A traditional water softener uses ion exchange: resin beads trade calcium and magnesium for sodium or potassium, and the system flushes the hardness out with brine from a salt tank. It is the only common household method that actually removes hardness. It makes the most sense when:
- Your water is hard or very hard, above about 7 to 10.5 gpg.
- You see scale on fixtures within days of cleaning.
- You have a tankless water heater, boiler or other equipment that scale damages quickly.
- You also have a small amount of iron, which many softeners can handle along with hardness.
Softeners need salt and periodic service. Our water softener maintenance guide covers what that involves.
When a Salt-Free Conditioner Fits
Salt-free conditioners, often using a process called template-assisted crystallization, do not remove calcium and magnesium. They change how the minerals behave so they are less likely to stick as hard scale inside pipes and water heaters. You will not get the slippery feel of softened water, and spotting on glass usually continues, but there is no salt to add and no brine discharge. They tend to work best on moderately hard water without much iron or manganese. Our comparison of salt-free conditioners vs. softeners explains the tradeoffs.
Size It From Your Test, Not the Box
A softener or conditioner sized from a guess will either run out of capacity or waste salt and water. Sizing depends on your hardness, iron, household size and water use. That is why we test first.
What About Drinking Water?
Hardness is not a drinking water health issue, and many people like the taste of mineral water. Softened water adds a small amount of sodium. If someone in your home is on a low-sodium diet, a reverse osmosis system at the kitchen tap, or a separate unsoftened line for drinking, solves it. If your well test finds arsenic, reverse osmosis or a dedicated arsenic system may be part of the plan anyway.
Serving Mercer County Homes
We test and treat water in Hopewell Township, Pennington, Lawrence, Princeton, West Windsor, Hamilton, Robbinsville, East Windsor and nearby towns. See our Mercer County service area page and the full range of systems on our water treatment page.
When to Call A Clear Alternative
Call us if you see scale building up within days of cleaning, if you are replacing a water heater or adding a tankless unit, if you just bought a home on a well in northern Mercer and want to know what is in the water, or if you are not sure whether you need a softener at all. A Clear Alternative is a family-run company that has been treating New Jersey water since 1991, working from 9230 Collins Ave in Pennsauken. We will test your water in your home at no charge and recommend only what it actually needs, including nothing at all if that is the right answer. Call 1-888-577-8088 to book your free in-home water analysis.
Frequently Asked Questions
Is Mercer County water hard?
It depends on location and source. Private wells in northern Mercer, around Hopewell and Pennington, are often hard to very hard. Southern and eastern areas and many public water customers can see lower hardness. Only a test tells you for sure.
At what hardness level do I need a water softener?
Under about 7 grains per gallon (120 mg/L), many homes do fine without one. Above about 10.5 grains per gallon (180 mg/L), a softener usually makes a real difference. In between it depends on what bothers you and what equipment you want to protect.
How do I convert mg/L to grains per gallon?
Divide mg/L (or ppm) of hardness as calcium carbonate by 17.1. For example, 171 mg/L is about 10 grains per gallon.
Will a salt-free conditioner make my water soft?
No. Salt-free conditioners do not remove calcium and magnesium. They help reduce scale inside plumbing and water heaters, but spotting and the feel of hard water usually remain.
Does a water softener remove arsenic?
No. If you are on a well in northern Mercer County, test for arsenic before choosing equipment. Arsenic needs reverse osmosis or a dedicated arsenic treatment system.
Does A Clear Alternative charge for a hardness test?
No. Our in-home water analysis is free. Call 1-888-577-8088 to schedule one anywhere in Mercer County.