Tap water safety: Experts advise on freshness and stagnation risks

tap water safety stagnation water drinking water quality microorganisms household plumbing

Experts and consumer protection agencies in Germany have provided guidance on the safety and quality of tap water. While tap water is highly monitored and generally safe to drink, its quality can change if it remains stagnant in pipes.

Water that has sat in plumbing for more than four hours is classified as stagnation water. This type of water may absorb substances from fixtures or show increased germ counts. To ensure freshness, experts recommend running the tap until the water becomes cool, which may take up to 30 seconds.

Stagnant water should not be used for cooking or drinking, though it can be repurposed for watering plants or cleaning. Additionally, when storing tap water in bottles, it is advised to use glass containers, store them in a cool, dark place, and consume them within one to two days to avoid bacterial growth from mouth contact.

Entities

Anja Schwengel-Exner · Germany · Hamburg Wasser · Verbraucherzentrale Bayern

Claims

What the coverage asserts, and how many sources carry each claim.

[● 7 SOURCES] Water for drinking or cooking should be run from the tap until it becomes cool. www.ruhrnachrichten.de · www.dattelner-morgenpost.de · www.fehmarn24.de · www.bbv-net.de · www.hellwegeranzeiger.de · +2 more
[● 7 SOURCES] Tap water is safe to drink provided there are no lead pipes in the building. www.ruhrnachrichten.de · www.dattelner-morgenpost.de · www.fehmarn24.de · www.bbv-net.de · www.hellwegeranzeiger.de · +2 more
[○ 1 SOURCE] Drinking directly from a bottle can increase germ counts as bacteria from the mouth enter the water. www.augsburger-allgemeine.de
[● 7 SOURCES] Running the tap for up to 30 seconds can ensure the water is fresh. www.ruhrnachrichten.de · www.dattelner-morgenpost.de · www.fehmarn24.de · www.bbv-net.de · www.hellwegeranzeiger.de · +2 more
[● 7 SOURCES] Water that has stood in pipes for more than four hours is considered stagnation water and may have higher germ counts. www.ruhrnachrichten.de · www.dattelner-morgenpost.de · www.fehmarn24.de · www.bbv-net.de · www.hellwegeranzeiger.de · +2 more
[○ 1 SOURCE] Stagnant water can lead to particles from household plumbing dissolving into the drinking water. www.wmn.de