Delft Colony Water

Visalia, CA · serves 454 · GroundwaterCA5403023
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 2023 water report
From your utility's Consumer Confidence Report · 16 contaminants tested
Above limit
Approaching limit
Within limits
Regulated contaminants — legally enforceable limits
Arsenic
0.003 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A naturally occurring element found in rock and soil. Gets into drinking water through erosion of natural deposits or runoff from industrial and agricultural sources.
Why it matters
Long-term exposure is linked to increased risk of skin, bladder, and lung cancer. There is no safe level for arsenic — the MCL of 10 µg/L balances health protection with treatment feasibility.
What to do
If your water is near or above the limit, a reverse osmosis filter certified to NSF/ANSI 58 removes over 90% of arsenic. Point-of-use filters at the kitchen tap are effective and affordable.
What the research says
Multiple peer-reviewed studies have found congenital heart defects including atrial septal defects at concentrations as low as 0.0005 mg/L20x below the US federal limit.
Barium
0.054 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
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.
Chromium
0.0028 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A metal found naturally in rocks, soil, and volcanic dust. Total chromium includes both chromium-3 (essential nutrient) and chromium-6 (the "Erin Brockovich" contaminant).
Why it matters
The federal MCL of 0.1 mg/L covers total chromium. Most health concern is specifically about chromium-6, which has no federal MCL but is monitored in some states.
What to do
If total chromium is well below the MCL, no action needed. If you want to know the chromium-6 level specifically, check if your utility tests for it separately.
Fluoride
0.13 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
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/L3x below the US federal limit.
Gross Alpha
4.39 pCi/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A screening test that measures total alpha radiation from all radioactive elements in water — including radium, uranium, and radon.
Why it matters
The MCL of 15 pCi/L protects against long-term cancer risk from radiation exposure.
What to do
No action needed at typical detection levels. If near the MCL, reverse osmosis and ion exchange filters can reduce radioactive contaminants.
Nitrate (as N)
4.05 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
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/L2x below the US federal limit.
Lead & copper — tested at your tap
Copper
0.0195 mg/L
Reference: Action level
Federal Lead and Copper Rule action level. Legally enforceable. Exceeding it triggers required corrective action by the utility.
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.
WHO recommendation
Sodium
27 mg/L
Reference: WHO guideline
World Health Organization drinking-water guideline. International guidance, not legally enforced in the US.
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

Other measurements

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

Hardness
85 mg/L· moderately hard
Chloride
18 mg/L
(EPA secondary standard: 250 mg/L)
Odor
1 TON
(EPA secondary standard: 3 TON)
Specific Conductance
310 µmhos/cm
(EPA secondary standard: 1600 µmhos/cm)
Sulfate
8.1 mg/L
(EPA secondary standard: 250 mg/L)
TDS
240 mg/L
(EPA secondary standard: 500 mg/L)
Zinc
0.017 mg/L
(EPA secondary standard: 5 mg/L)

CCR data in early access — values are extracted from utility PDFs and may contain errors. Verify with your utility's 2023 CCR report.

Source: DELFT COLONY WATER Consumer Confidence Report 2023 · 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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2 wells
Water Sources

Visalia pumps water from two groundwater wells drawing from the Central Valley aquifer system.

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