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City Of Baltimore

Baltimore, MD · serves 1,600,000 · Surface waterMD0300002
All clear
All monitored contaminants within federal limits. Last updated from the most recent CCR and EPA monitoring data available.
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Measured in your 2025 water report
From your utility's Consumer Confidence Report · 13 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
TTHM132.6 µg/L80 µg/L~1.7× the limit
Above limit
Approaching limit
Within limits
Regulated contaminants — legally enforceable limits
Barium▸
0.0361 mg/L
MCLlegally enforceable
Sample history
Range: 0.02 to 0.04 mg/L across 2 samples (Jul 1, 2025).
What is it?
A naturally occurring metal found in mineral deposits. Enters water through erosion of natural deposits or discharge from drilling and metal refining operations.
Why it matters
At high levels, barium can cause increased blood pressure. Levels well below the MCL of 2 mg/L are not a health concern.
What to do
No action needed at typical detection levels. Barium is rarely found near its MCL in treated drinking water.
Fluoride▸
0.777 mg/L
MCLlegally enforceable
Sample history
Range: 0.61 to 0.78 mg/L across 6 samples (May to Jul 2025).
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)▸
1.5 mg/L
MCLlegally enforceable
Sample history
Range: 1.12 to 1.5 mg/L across 3 samples (May to Jul 2025).
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.
Disinfection byproducts
HAA5▸
58 µg/L
MCLlegally enforceable
Sample history
Range: 4.9 to 58 µg/L across 82 samples (Jan to Oct 2025).
Compliance for HAA5 is calculated as a locational running annual average (LRAA), not single samples. This system's LRAA was 39.63 µg/L, within the 60 µg/L MCL.
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▸
23 µg/L
MCLGhealth goal, unenforced
Sample history
Range: 17.4 to 23 µg/L across 2 samples (Oct 8, 2025).
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▸
1.15 µg/L
MCLGhealth goal, unenforced
Sample history
Range: 0.77 to 1.15 µg/L across 2 samples (Oct 8, 2025).
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▸
6.31 µg/L
Sample history
Range: 5.6 to 6.31 µg/L across 2 samples (Oct 8, 2025).
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▸
133 µg/L ×1.7
MCLlegally enforceable
Sample history
Range: 15.2 to 132.6 µg/L across 81 samples (Jan to Oct 2025).
Compliance for TTHM is calculated as a locational running annual average (LRAA), not single samples. This system's LRAA was 76.72 µg/L, within the 80 µg/L MCL.
The high single-sample value is shown because brief exposures can matter for some health outcomes, even when annual averages remain compliant.
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.
WHO recommendation
Sodium▸
20.8 mg/L
WHO guidelineinternational, unenforced
Sample history
Range: 20 to 20.8 mg/L across 2 samples (Jul 1, 2025).
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.
OTHER
CARBON, TOTAL▸
2.36 MG/L
No additional information available for this contaminant.
% of limit

Other measurements

These describe characteristics of the water that aren’t health risks at typical levels — mineral content, taste, hardness, and similar.

Alkalinity
▸
71 mg/L
Sulfate
▸
20.6 mg/L
(EPA secondary standard: 250 mg/L)

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

Source: CITY OF BALTIMORE Consumer Confidence Report 2025 · Extracted by WaterScore
Model estimates
Private Well Risk

Do you have or use a private well? Estimated contamination risk for wells in this area based on local geology and land use.

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7 sites within 10 mi
Nearby Superfund Sites

7 EPA Superfund sites within 10 miles. Proximity does not necessarily mean your water is affected.

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Surface water
Water Sources

Baltimore draws from surface water — Liberty Reservoir, Loch Raven (Baltimore Pipe), and Susquehanna (Baltimore Pipe). Drought directly affects reservoir levels and river flow.

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Spatial context
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