Tap Water Quality in Old Guildford, NSW
Postcode 2161 · Supplied by Sydney Water via Prospect South
Quality Score
About Old Guildford
Old Guildford is a suburb of 2,857 residents in New South Wales (postcode 2161). The median age is 29. It falls within the Sydney Water area. Neighbouring suburbs include Yennora, Guildford, Fairfield East, Guildford West.
Most residents own their home with a mortgage (35%), while 33% rent, while 28% own outright. The median household income is $78,572 per year. The top countries of birth for residents are Lebanon (34%), Afghanistan (7%), and China (7%).
Tap water in Old Guildford is supplied by Sydney Water. The suburb receives water via the Prospect South supply zone.
Water quality summary
Based on 2024-25 water quality reports, Old Guildford achieves a WaterScore of 9.5 out of 10, rated excellent overall. Water hardness measures 50.7 mg/L, classified as soft. This is gentle on appliances and skin, with minimal limescale buildup expected. The pH level is 7.9, which is within the ADWG guideline range of 6.5–8.5. The water is fluoridated at 1.01 mg/L, within the recommended range of 0.6–1.1 mg/L for dental health, well under the ADWG maximum of 1.5 mg/L. Chlorine, used for disinfection, measures 0.04 mg/L — well within the ADWG guideline of 5 mg/L. Total dissolved solids (TDS) measure 137 mg/L, considered low against the ADWG guideline of 600 mg/L. Turbidity is 0.12 NTU, indicating clear water, within the ADWG guideline of 5 NTU. E. coli was not detected in testing, meeting the ADWG standard for microbiological safety.
Compare with nearby suburbs: Yennora , Guildford , Fairfield East
Census Data
Suburb snapshot
Population
Median Age
Median Income
Owner-occupied
Recommended filters for Old Guildford
Products matched to your water profile
ZeroWater
2.8L 5-Stage Jug (IAPMO Certified: PFOA/PFOS + Lead)
4.2 · 5,315 ratings on Amazon
Ideal for Old Guildford — removes fluoride (currently 1.01 mg/L).
iSpring
RCC7AK 6-Stage Under-Sink RO (with Alkaline Re-min)
4.6 · 13,756 ratings on Amazon
Ideal for Old Guildford — removes fluoride (currently 1.01 mg/L).
Purewell
8.5L Stainless Steel Gravity System
4.4 · 1,137 ratings on Amazon
A reliable 8.5l stainless steel gravity system suitable for Old Guildford's water profile.
Comparison
How Old Guildford compares
Compared to New South Wales and national averages
| Metric | Old Guildford | NSW Avg | National Avg |
|---|---|---|---|
| Hardness | 50.7 mg/L | 45.9 mg/L | 85.3 mg/L |
| pH | 7.9 | 7.7 | 7.8 |
| Fluoride | 1.01 mg/L | 1 mg/L | 0.7 mg/L |
| Chlorine | 0.04 mg/L | — | — |
| Turbidity | 0.12 NTU | 0.2 NTU | 0.4 NTU |
| TDS | 137 mg/L | 116.3 mg/L | 275.7 mg/L |
Full Results
Detailed water quality data
All values compared against Australian Drinking Water Guidelines (ADWG)
| Parameter | Value | Unit | ADWG Guideline | Status |
|---|---|---|---|---|
| Iron | 0.007 | mg/L | < 0.3 | Good |
| Aluminium | 0.014 | mg/L | < 0.2 | Good |
| Manganese | 0.0018 | mg/L | < 0.1 | Good |
| Copper | 0.015 | mg/L | < 2 | Good |
| Zinc | 0.003 | mg/L | No limit | Measured |
| Ammonia | 0.354 | mg/L | No limit | Measured |
| Turbidity | 0.12 | NTU | < 5 | Good |
| Colour | 4 | HU | < 15 | Good |
| Dissolved Oxygen | 105.1 | % saturation | No limit | Measured |
| Total Dissolved Solids | 137 | mg/L | < 600 | Good |
| Sulfate | 8.8 | mg/L | < 500 | Good |
| Hardness | 50.7 | mg/L | < 200 | Good |
| pH | 7.9 | pH units | 6.5 – 8.5 | Normal |
| Temperature | 19.3 | degrees C | No limit | Measured |
| E. coli | 0 | orgs/100 mL | < 0 | Compliant |
| Free Chlorine | 0.04 | mg/L | < 5 | Good |
| Monochloramine | 1.74 | mg/L | < 3 | Good |
| Fluoride | 1.01 | mg/L | < 1.5 | Good |
| Trihalomethanes | 0.09 | mg/L | < 0.25 | Good |
| Ndma | 0.0001 | mg/L | No limit | Measured |
| Chloride | 0.004 | mg/L | < 250 | Good |
| PFOS + PFHxS | 0.0014 | µg/L | PFOS < 0.008, PFHxS < 0.03 | Good |
| PFOA | 0.0002 | µg/L | < 0.2 | Good |
Safety
Safety assessment
Based on 23 parameters tested, all results fall within Australian Drinking Water Guidelines. E. coli was not detected, meeting the ADWG standard for microbiological safety.
Based on comparison with Australian Drinking Water Guidelines (ADWG)
Explained
What these numbers mean
Soft (50.7 mg/L)
Water Hardness
Your water is classified as soft, which means minimal limescale buildup on fixtures and appliances. Soap and shampoo will lather easily, and you should notice no drying effects on skin or hair. Hot water systems and kettles are unlikely to suffer scale-related efficiency losses.
Normal Range
pH Level
pH of 7.9 is within the ideal range of 6.5–8.5. The ADWG recommends pH between 6.5 and 8.5 for drinking water.
Fluoridated
Fluoride
Fluoride at 1.01 mg/L. Within the recommended 0.6–1.1 mg/L range for dental health.
Chlorine
Disinfection
Chlorine measured at 0.04 mg/L, well within the ADWG guideline of 5 mg/L. Used for disinfection to keep water safe. May affect taste slightly — refrigerating water or using a carbon filter can help.
Learn more about these measurements in our water quality glossary — including Hardness , pH , Fluoride , and ADWG guidelines .
Advice
Practical tips for residents
Chlorine Levels Are Low
Chlorine in Old Guildford measures 0.04 mg/L, which is low. Filling a jug and letting it stand for 30 minutes will reduce any residual taste.
Soft Water Advantage
Old Guildford's water is soft at 50.7 mg/L. You can use less soap and detergent, as it lathers easily with softer water.
Fluoride in Your Water
Fluoride measures 1.01 mg/L in Old Guildford. Australian guidelines allow up to 1.5 mg/L. This is added by utilities to support dental health in the community.
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FAQ
Frequently asked questions
Is tap water safe to drink in Old Guildford?
How hard is the water in Old Guildford?
What water utility supplies Old Guildford?
Does Old Guildford water have fluoride?
What is the water quality score for Old Guildford?
What is the population of Old Guildford?
Supplier
Water utility
- Utility
- Sydney Water
- Supply Zone
- Prospect South
- Data Source
- Sydney Water — quarterly prospect south q2 202425, quarterly prospect south q3 202425, quarterly prospect south q4 202425
Nearby
Nearby suburbs
Same water utility, similar water quality
Similar Quality
Suburbs with similar water quality
Suburbs scoring between 8.5 and 10.0
Utility reports average the grid — not your home
Old Guildford's water meets ADWG standards at the source, but old pipes, roof tanks, and ageing plumbing can add lead, copper or bacteria before the water reaches your tap. These won't show up in your utility report.
Check your own tap before buying a filter or assuming the suburb average matches your home.
Tetra
EasyStrips 6-in-1 Water Test (100 strips)
4.6 · 8,650 ratings on Amazon
Tests 6 parameters in 60 seconds: hardness, chlorine, pH, nitrate, nitrite, alkalinity. Cheapest way to verify your utility data.
Test my tap →Sponsored Amazon link. Check Amazon for current price and availability.
Heavy Metals
Drinking Water Test Kit (Lead, Copper, Iron, Mercury)
4.2 · 250 ratings on Amazon
20 tests. Detects lead, copper, iron, mercury — the things utility reports miss. Mobile-app results, EPA-standard thresholds.
Check metals kit →Sponsored Amazon link. Check Amazon for current price and availability.
Guides for Sydney
In-depth articles on the water supply that serves Old Guildford
Cite
Cite this page
Free to quote and reuse with a credit to WaterScore and a link to this page. Journalists and researchers can find key figures and contacts on our press and data page.
WaterScore. (2026). Tap water quality in Old Guildford, NSW [Data set]. Compiled from Sydney Water data (2024-25 annual report). https://waterscore.com.au/water-quality/old-guildford-nsw/
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Related
Explore more
Related pages for Old Guildford, NSW
Is tap water safe?
Safety assessment
Water hardness
50.7 mg/L
Best water filter
Filter recommendations
New South Wales water quality
State coverage
Sydney Water
Water utility
Compare with Yennora
Old Guildford vs Yennora
Compare with Guildford
Old Guildford vs Guildford
Compare with Fairfield East
Old Guildford vs Fairfield East
Disclaimer: The information on this page is for general informational purposes only and does not constitute medical advice, health recommendations, or professional guidance. Water quality data is sourced from Sydney Water (2024-25 annual report) and reflects conditions at the time of utility testing — it may not reflect real-time water quality at your tap. Actual water quality can vary due to local plumbing, seasonal changes, and distance from the treatment plant. For specific health concerns, consult a qualified health professional. For the most current water quality information, contact your local water utility directly. See our Terms of Use.