How often should you test well water in New Jersey?

Every year for bacteria, nitrate and pH. That is the schedule the state itself recommends: total coliform, nitrate and pH at least annually, then lead, VOCs, iron and manganese at least every five years, and arsenic, mercury and gross alpha radioactivity at least once, more often if a result comes back elevated. EPA’s national guidance says the same thing about the annual trio.

Testing is also the front end of every water treatment decision we make, because in South Jersey the test results follow a pattern worth knowing before you pay for a full panel.

The schedule, in one table

The trigger list matters as much as the calendar. The state’s guidance says to retest whenever the well cap comes off, after flooding or a nearby chemical spill, when the water changes color, taste or smell, and when unexplained stomach illness keeps making the rounds of the household.

The law at sale and lease

New Jersey’s Private Well Testing Act has run since 2002, and it is the one time testing stops being advice and becomes required. At a sale, the contract must require the test, and closing cannot happen until buyer and seller have both received, reviewed and signed off on the results. Results stay valid for one year, except coliform, which expires at six months, a detail that catches listings that sit.

At a rental, the landlord pays: a full test at least every five years, with written results to every tenant within 30 days of receiving them.

The full panel covers up to 43 parameters statewide, from bacteria and nitrate through VOCs, lead, arsenic, gross alpha, and since 2021, PFAS. And there is a county clause written for exactly our service area: samples from Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, Monmouth, Ocean and Salem counties must also be tested for mercury. The state estimates the full panel at $1,200 to $1,500. Failing it does not block the sale; it starts the treatment conversation.

What South Jersey tests actually find

The state has two decades of PWTA data, and the pattern for our counties is consistent.

Acidic water, nearly everywhere. The state’s own report says southern New Jersey groundwater tends to run acidic, and 44 percent of the 51,000 wells in the first statewide dataset came back below the healthy pH floor of 6.5. Acidic water eats copper plumbing, which is also how lead gets into glasses: the state found the lead source is almost always the home’s own pipes, leached by corrosive water. The fix on our side is an acid neutralizer, and it is the most common piece of equipment we install.

Iron and manganese staining. Twenty-nine percent of tested wells exceeded the iron limit and 19 percent the manganese limit statewide. That is the orange toilet ring and the black streaks in the dishwasher, and it is filter work, sometimes paired with a water softener.

Radium, the quiet one. Gross alpha radioactivity is the finding South Jersey should actually plan around. State health department data by township: 63 percent of tested wells in Upper Deerfield exceeded the radioactivity standard, 45 percent in Waterford, 40 percent in Pittsgrove, 21 percent in Franklin Township, and 18 percent in Monroe Township. Radium is tasteless and invisible, rides acidic water, and only shows up on a lab test. The health department has even run free radioactivity, iron and manganese testing for eligible South Jersey towns in recent summers; registration opens periodically, so the offer is worth watching for.

One more radium wrinkle from USGS research: radium levels in our aquifer have been rising where road salt meets acidic groundwater, which means a clean result from ten years ago is not a clean result today.

Nitrate in farm country. Cumberland and Salem counties post the state’s highest nitrate exceedance rates, at 11 and 9 percent of wells, and USGS sampling around Glassboro found 60 percent of shallow agricultural-area wells over the limit. Nitrate matters most for infants, and boiling makes it worse, not better. Shallow wells near farmland should keep this one on the annual list. Deeper wells draw from cleaner water, which is one reason a replacement well is sometimes the treatment plan.

Salt near the shore. Chloride and sodium are not on the required PWTA panel, so a Cape May County owner can pass the full $1,250 test and still not know whether the sea is creeping into the well. Ask for them separately if you are near the bay or the islands. USGS has documented more than 100 domestic wells abandoned to saltwater intrusion in Cape May County.

Getting a test that counts

Three rules make a New Jersey result official. The sample must be collected by a certified lab or its representative. It must be raw water, with any treatment system bypassed, which is why kitchen-tap samples taken downstream of a softener mislead people. And pH must be analyzed on the spot, within minutes, which no mailed-in kit can do.

Consumer test strips have a place: a free early warning between real tests. They have no standing at a closing, and they cannot see radium, arsenic, VOCs or PFAS at all.

One number from the state’s door-to-door South Jersey sampling deserves the last word: 27 percent of the treatment systems they checked were not actually reducing radioactivity to safe levels, mostly from missed maintenance. Equipment only counts if it is working, which is why we retest after every install and put maintenance on a schedule.

The short version

Test bacteria, nitrate and pH yearly, run the radium test at least once if you are anywhere in our farm belt, and always retest after treatment goes in. We test, we read the numbers with you, and we size equipment to what the lab actually found, never to a sales pitch. Call (856) 207-7373 and we will get a certified sample pulled.