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Water Hardness in 13691

Theresa, New York · Jefferson County

145 PPM
8.5 GPG
Moderately Hard
0Soft60120180300+
High Confidence - USGS Monitoring

Dataset updated March 9, 2026Matched to 4 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

How this ZIP reading is built

This ZIP reading is built from 4 matched water systems. When more than one system is matched, the displayed value is weighted toward larger known service populations when that data is available.

Source basis
4 USGS-backed sources
4 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily surface water
Surface-water hardness can shift with reservoirs, runoff, season, and treatment. This profile is weighted by known population served across matched systems.
Data recency
March 9, 2026
Dataset rebuilt March 9, 2026; individual utility reporting years can vary.

Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.

Water Systems Serving 13691

These are the systems matched to this ZIP code. The displayed ZIP value is weighted toward larger known service populations when population data is available.

4 water systems
PWSID is the public water system identifier. Data Source shows whether the hardness value comes from a treated-water report, USGS monitoring, or a local estimate; source year is shown when available.
Fort Drum
NY2212214
Hard
227 PPMsurface water34,000 servedHigh Confidence - USGS Monitoring
Watertown City
NY2202346
Soft
42 PPMsurface water27,861 servedHigh Confidence - USGS Monitoring
Theresa Village
NY2202344
Hard
227 PPMgroundwater950 servedHigh Confidence - USGS Monitoring
Indian River Estates, Ltd.
NY2222513
Hard
227 PPMgroundwater303 servedHigh Confidence - USGS Monitoring

Nearby Zip Codes

136731461367514413679144136081451363714513607148136561461360214413640144136031441361614413638144

What This Means For You

Use this ZIP reading as a local planning estimate, not a final treatment specification. Hardness can vary by utility zone, seasonal blend, private well, and building plumbing. Confirm your tap reading with a utility report or home hardness test before sizing equipment.

MethodologyData sourcesHow to test your water

Know your water hardness?

If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Theresa, NY (13691).

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Frequently Asked Questions

Is the water hard in Theresa, NY (13691)?

The average water hardness in 13691 is 145 PPM (8.5 GPG), which is classified as moderately hard.

Do I need a water softener in 13691?

With hardness of 145 PPM, a water softener is worth considering for homes in 13691.

Is hard water in 13691 safe to drink?

Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.

How many water systems serve 13691?

Zip code 13691 in Theresa, New York is served by 4 water systems.

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