Water Hardness in Sector PO10 7

Water Supply Zone Report • Distribution Area Managed by Portsmouth Water

Water Quality Summary: Sector PO10 7

✓ Verified Zone-Level Data (DWI / Defra)
Average Mineral PPM250 PPMHard
English Clark Scale17.5 °Clark25.0 °fH • 14.0 °dH
Boiler Heat Loss10% – 15%Est. thermal efficiency drag
Bosch Dishwasher SettingH04Softener salt required
Direct Answer & Quick Diagnostic

Tap water in postcode sector PO10 7 has an average water hardness of 250 PPM (mg/L CaCO₃), which equals 17.5° Clark (25.0°fH / 14.0°dH). Classified as hard water distributed by Portsmouth Water, domestic dishwashers require setting H04 and combi boilers face an estimated thermal efficiency drag of 10% – 15% without scale protection.

Comprehensive Hydro-Geological Analysis

Water Hardness Breakdown for Sector PO10 7

According to regional catchment disclosures for PO10 7, municipal tap water managed by Portsmouth Water presents a mineral density of 250 PPM (17.5 English degrees). This data covers approximately 293 residential and commercial addresses in the PO10 area.

Registering 250 PPM, tap water across PO10 7's 293 postcodes carries significant calcium concentrations. Uninhibited hot water use accelerates limescale deposits on heating elements, potentially causing a 10% – 15% loss in boiler heat transfer efficiency over prolonged operating cycles.

Water quality in PO10 7 is monitored continuously under the Water Supply (Water Quality) Regulations. Environmental testing ensures that the 250 PPM mineral density supplied by Portsmouth Water remains compliant with all Drinking Water Inspectorate (DWI) parameters.

Bathing and laundering across the 293 postcodes of PO10 7 is influenced by the 250 PPM mineral density. Surfactants in shampoos and detergents interact with calcium salts, requiring +35% extra laundry detergent to overcome calcium neutralization to achieve thorough cleansing and preserve fabric softness.

Correct softener regeneration is critical when running appliances on 250 PPM water in PO10 7. Setting your dishwasher to H04 optimizes salt consumption while ensuring spot-free drying results across PO10.

Standardized Water Chemistry Metrics

Water Hardness Measurement Conversions for Sector PO10 7

Standardised unit equivalents used across British plumbing standards (BS 7593), European appliance manuals, and water testing:

Measurement ScaleSymbol / StandardValue in PO10 7
Parts Per Million (UK/US standard)PPM / mg/L CaCO₃250 PPM
English Clark Degrees°Clark / °e17.5 °Clark
French Degrees°fH25.0 °fH
German Degrees (General Hardness)°dH / dGH14.0 °dH
Millimoles Per Litremmol/L2.50 mmol/L
Grains Per Gallon (US)gpg14.6 gpg
NP
Updated: 17 August 2025 • DWI & Defra Compliant DataNguyễn Hạc Phong • Lead Water Data Engineer
Drinking Water Inspectorate (DWI)
Water Hardness Level

250 PPM (mg/L)

17.5 °ClarkHard
0 PPM (Soft)100 PPM200 PPM (Hard)300+ PPM (Very Hard)
Water supplied by Portsmouth Water in PO10 7 is categorized as Hard. High mineral content causes rapid limescale build-up on heating elements and appliances.
Dishwasher Setup Guide

Exact Water Softener Setting for PO10 7

Select your dishwasher brand to get the manufacturer-recommended salt setting for this area.

Recommended Setting:H04
⚠️ Dishwasher salt is required to prevent cloudy glasses and internal scale buildup.
Boiler Efficiency Loss~12%Extra energy cost per year
Limescale Formation RiskHighOn taps, kettles & showers
Detergent Needed+30% DoseFor laundry & dishwashing
Recommended Solutions

Protect Your Appliances in PO10 7

Essential

Dishwasher Regeneration Salt

Prevents limescale buildup in water softeners and stops cloudy film on glassware.

Check Price on Amazon
Skin & Hair Protection

Shower Head Water Filter

Reduces chlorine & hard minerals to protect against dry skin, eczema, and hair damage.

Check Shower Filters
Maintenance

Appliance Descaler Tablets

Quickly dissolves limescale deposits inside kettles, coffee machines, and washing machines.

View Descalers
Frequently Asked Questions

Water Hardness FAQs for Sector PO10 7

Q: What is the official water hardness level in sector PO10 7?

Tap water in sector PO10 7 has an average mineral density of 250 PPM (mg/L), which equals 17.5° Clark, 25.0°fH, or 14.0°dH. It is officially categorized as hard water supplied by Portsmouth Water.

Q: What dishwasher water softener setting is needed for PO10 7?

For Bosch, Siemens, and Neff dishwashers in sector PO10 7 (250 PPM), the recommended softener setting is H04. Beko models typically require Level 3 or 4.

Q: Will hard water damage central heating boilers in PO10 7?

Yes. At 250 PPM, calcium carbonate precipitation will build scale layers on heating elements over time, potentially reducing boiler heat transfer efficiency by 10% – 15% without proper filtration or descaling.

Q: Who is the regulated water supplier for sector PO10 7?

Mains water across postcode sector PO10 7 is distributed and monitored by Portsmouth Water in accordance with Drinking Water Inspectorate (DWI) quality standards.

Other Postcode Sectors in PO10

Explore water hardness and limescale risks in neighbouring areas within PO10

Sector PO10 8250 PPM (Hard)
Sector PO10 9250 PPM (Hard)

Curious how Sector PO10 7 compares?

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