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PA American Water CO West

Mechanicsburg, PA · serves 93,368 · Surface waterPA7210029
Action recommended
PFAS detected above the federal limit. Utilities have until 2029 to install treatment; until then, a certified filter handles it at the tap.
See filter recommendations →
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Measured in your 2025 water report
From your utility's Consumer Confidence Report · 17 contaminants tested
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Contaminants detected above federal limits
Your utility's own 2025 water report disclosed the following levels. Utilities have until 2029 to comply with new federal limits.
ContaminantDetected LevelFederal LimitHow Far Over
PFOS9.55 ng/L4 ng/L~2.4× the limit
PFOA4.125 ng/L4 ng/L~1.0× the limit
Above limit
Approaching limit
Within limits
Regulated contaminants — legally enforceable limits
Fluoride▸
0.65 mg/L
MCLlegally enforceable
What is it?
Naturally occurring mineral, also added to many water systems to prevent tooth decay. The MCL (4 mg/L) is much higher than the typical added amount (0.7 mg/L).
Why it matters
At levels near the MCL, long-term exposure can cause skeletal fluorosis (bone pain and tenderness). The secondary standard of 2 mg/L triggers a required public notice about dental fluorosis risk in children.
What to do
Levels below 2 mg/L are within the range considered safe. If above 2 mg/L, children under 9 may be at risk for dental fluorosis — talk to your pediatric dentist.
What the research says
Multiple peer-reviewed studies have found lower IQ in children and potential thyroid disruption at concentrations as low as 1.5 mg/L — 3x below the US federal limit.
Nitrate (as N)▸
3.69 mg/L
MCLlegally enforceable
What is it?
Comes from fertilizer runoff, septic systems, and erosion of natural deposits. One of the most common groundwater contaminants in agricultural areas.
Why it matters
Nitrate above 10 mg/L can cause "blue baby syndrome" (methemoglobinemia) in infants under 6 months — it interferes with blood's ability to carry oxygen. Adults can tolerate higher levels.
What to do
If you have an infant on formula and your water is above 5 mg/L, consider using bottled water for formula preparation. Boiling water does NOT remove nitrate — it concentrates it.
What the research says
Multiple peer-reviewed studies have found neural tube defects, preterm birth, and low birth weight at concentrations as low as 5 mg/L — 2x below the US federal limit.
Lead & copper — tested at your tap
Copper▸
2025-0601_2025-0930
0.295 mg/L
Action levellegally enforceable
What is it?
Leaches from copper household plumbing and pipes. Some copper is a normal part of drinking water infrastructure.
Why it matters
Short-term exposure above the action level of 1.3 mg/L can cause gastrointestinal distress. Long-term exposure can cause liver and kidney damage. At typical detected levels (well below the AL), copper is not a health concern.
What to do
If above the action level, run your tap for 30 seconds before drinking. Copper levels decrease as water flows through the pipes.
Disinfection byproducts
TCAA▸
4.67 µg/L
MCLGhealth goal, unenforced
What is it?
A haloacetic acid formed during chlorine disinfection of source water containing organic matter. One of five HAAs regulated together as HAA5.
Why it matters
EPA sets the MCLG at 0.02 mg/L based on liver effects observed in animal studies. Classified as suggestive but not yet established as a human carcinogen. Regulated as part of the HAA5 group (60 µg/L).
What to do
Like other HAAs, TCAA is reduced by carbon-block filtration at point-of-use (NSF/ANSI 53 certified for VOCs). Reducing the parent organic load — through utility-side treatment changes — is the more effective approach at scale.
DCAA▸
6.07 µg/L
What is it?
A haloacetic acid formed when chlorine reacts with natural organic matter during disinfection. One of five HAAs regulated together as HAA5 (limit: 60 µg/L).
Why it matters
EPA classifies DCAA as a likely human carcinogen and sets the MCLG at zero. Animal studies show liver, neurological, and reproductive effects, and developmental concerns have been raised at high prenatal exposures. The HAA5 group limit reflects feasibility, not the MCLG.
What to do
DCAA forms in your utility's treatment process. Point-of-use carbon-block filters certified for VOC reduction (NSF/ANSI 53) can reduce HAAs. Running cold tap water briefly before drinking helps clear water that has sat in pipes where DBPs continue to form.
HAA5▸
10.7 µg/L
MCLlegally enforceable
What is it?
Another group of disinfection byproducts formed when chlorine reacts with natural organic matter. HAA5 measures the five most common species.
Why it matters
Long-term exposure above the MCL of 60 µg/L (0.060 mg/L) is associated with increased cancer risk. Like THMs, the MCL is based on a running annual average.
What to do
Activated carbon filters can reduce HAA5. If your system consistently approaches the limit, a reverse osmosis filter provides more complete removal.
Chloroform▸
13.8 µg/L
MCLGhealth goal, unenforced
What is it?
A disinfection byproduct formed when chlorine reacts with naturally occurring organic matter in source water. The most common of the four trihalomethanes.
Why it matters
Long-term exposure has been associated with increased risk of bladder cancer and possibly colorectal cancer. EPA classifies it as a probable human carcinogen and sets an MCLG of 0.07 mg/L based on liver effects. Regulated together with three other trihalomethanes under the TTHM standard (80 µg/L).
What to do
Chloroform levels are largely a function of how your utility manages disinfection. If TTHM is approaching the limit, a carbon-block filter (NSF/ANSI 53 certified for VOCs or specifically for trihalomethanes) at point-of-use reduces it. Letting cold water run for 30 seconds before drinking can also help, since chloroform forms in the distribution system.
DBCM▸
1.46 µg/L
MCLGhealth goal, unenforced
What is it?
A brominated trihalomethane formed when chlorine reacts with bromide-containing organic matter. More common in source waters with higher bromide levels — often coastal or groundwater systems.
Why it matters
EPA sets the MCLG at 0.06 mg/L based on liver and kidney effects. Some evidence suggests DBCM may be carcinogenic, though the data is less clear than for BDCM and bromoform. Regulated together with the other three trihalomethanes under TTHM.
What to do
Like other THMs, DBCM forms in the distribution system as chlorine reacts over time. A point-of-use carbon-block filter (NSF/ANSI 53) reduces it along with related compounds.
BDCM▸
5.21 µg/L
What is it?
A brominated trihalomethane formed when chlorine reacts with organic matter and bromide in source water. One of four trihalomethanes regulated together under TTHM.
Why it matters
EPA classifies BDCM as a probable human carcinogen and sets the MCLG at zero, meaning the agency identifies no safe lifetime exposure level. Studies link it to bladder and colon cancer, and to reproductive and developmental effects at high exposures. The enforceable limit (80 µg/L for total TTHM) reflects what's feasible to achieve, not what's safest.
What to do
BDCM is formed in your utility's system, so reducing it generally means reducing total disinfection byproducts there. At point-of-use, a carbon-block filter certified for VOCs or trihalomethanes (NSF/ANSI 53) reduces BDCM along with other THMs.
TTHM▸
20.5 µg/L
MCLlegally enforceable
What is it?
Formed when chlorine used to disinfect water reacts with natural organic matter. Includes chloroform, bromoform, and related compounds. The trade-off: disinfection prevents waterborne disease, but creates these byproducts.
Why it matters
Long-term exposure above the MCL of 80 µg/L (0.080 mg/L) is associated with increased cancer risk and possible reproductive effects. The MCL is based on a running annual average, not a single sample.
What to do
If your system is near or above the limit, an activated carbon filter (including pitcher filters like Brita) can reduce THMs. Running water for a minute before drinking also helps, as THMs are volatile and dissipate.
PFAS
PFOS▸
9.55 ng/L ×2.4
MCLlegally enforceable
What is it?
Perfluorooctane sulfonic acid — a "forever chemical" widely used in firefighting foam, stain repellents, and food packaging. Persists indefinitely in the environment.
Why it matters
MCL of 4 ng/L, same as PFOA. PFOS is linked to cancer, immune suppression, thyroid disease, and elevated cholesterol. It accumulates in the body over years of exposure.
What to do
Same as PFOA — reverse osmosis or NSF/ANSI 53-certified activated carbon filters. Utilities have until 2029 to comply.
What the research says
Multiple peer-reviewed studies have found preeclampsia, reduced birth weight, and impaired immune response in infants with a dose-response relationship across the range of concentrations found in drinking water.
PFOA▸
4.13 ng/L ×1.0
MCLlegally enforceable
What is it?
Perfluorooctanoic acid — a "forever chemical" used in non-stick coatings, stain repellents, and firefighting foam. It doesn't break down in the environment or your body.
Why it matters
The EPA set an MCL of 4 ng/L (parts per trillion) in 2024 — one of the strictest drinking water standards ever set. PFOA is linked to cancer, thyroid disease, immune system effects, and reproductive harm.
What to do
A reverse osmosis filter (NSF/ANSI 58) or activated carbon filter (NSF/ANSI 53 certified for PFOA) can reduce levels by 90%+. Pitcher filters with activated carbon provide partial reduction. Utilities have until 2029 to comply with the new MCL.
What the research says
Multiple peer-reviewed studies have found preeclampsia, low birth weight, and immunotoxicity in infants with a dose-response relationship across the range of concentrations found in drinking water.
PFHxS▸
0.675 ng/L
MCLlegally enforceable
What is it?
Perfluorohexane sulfonic acid — a shorter-chain PFAS compound found in firefighting foam and consumer products.
Why it matters
MCL of 10 ng/L. Like other PFAS, it persists in the body and environment. Linked to thyroid and immune effects.
What to do
Reverse osmosis filters are most effective for PFAS removal. Activated carbon provides partial reduction.
PFBS▸
3.17 ng/L
MCLlegally enforceable
What is it?
Perfluorobutane sulfonic acid — a short-chain PFAS compound. Part of the EPA's Hazard Index approach for PFAS mixtures.
Why it matters
Regulated as part of the PFAS mixture Hazard Index, not as a standalone MCL. Short-chain PFAS are harder to remove from water but are excreted from the body faster than long-chain PFAS.
What to do
Reverse osmosis is the most effective removal method for short-chain PFAS.
Disinfectants — MRDL
Chlorine▸
3.04 mg/L
MRDLlegally enforceable
What is it?
Added intentionally to kill bacteria and viruses. A chlorine residual in your tap water means the disinfection is still active through the distribution system — this is by design.
Why it matters
The MRDL of 4 mg/L is the maximum allowed. Typical levels are 0.5–2 mg/L. Chlorine at normal levels is not a health concern — the disease risk from untreated water is far greater.
What to do
If you don't like the taste, let water sit in an open pitcher for 30 minutes or use an activated carbon filter. Both remove chlorine taste and odor.
WHO recommendation
Sodium▸
37.4 mg/L
WHO guidelineinternational, unenforced
What is it?
Naturally present in most water sources. Also increases from road salt, water softeners, and natural mineral deposits.
Why it matters
There is no federal MCL for sodium. The WHO suggests a guideline of 200 mg/L for people on sodium-restricted diets. For most people, sodium in water is a small fraction of dietary intake.
What to do
If you're on a sodium-restricted diet and your water is above 20 mg/L, talk to your doctor. For most people, no action needed.
% of limit

CCR data in early access — values are extracted from utility PDFs and may contain errors. Verify with your utility's 2025 CCR report.

Source: PA AMERICAN WATER CO WEST Consumer Confidence Report 2025 · Extracted by WaterScore
Measured data
Private Well Risk

Do you have or use a private well? Measured concentrations from nearby private wells sampled within 5 miles.

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1 site within 10 mi
Nearby Superfund Sites

1 EPA Superfund site within 10 miles. Proximity does not necessarily mean your water is affected.

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Surface water
Water Sources

Mechanicsburg uses both groundwater and surface water sources, giving it more supply flexibility during drought conditions. Emergency backup sources are available if primary supplies are disrupted.

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Spatial context
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