Focus on Healthy Living: Reducing the Risk of Legionella with Smart Solutions Before Summer Vacation

Eschborn, June 29, 2026. As summer vacation begins in the first federal states (Hesse, Rhineland-Palatinate, Saarland), drinking water hygiene in residential buildings is coming into sharper focus. Prolonged absences and vacant units can cause water to stagnate in pipes for several days, thereby increasing the risk of Legionella growth. Property owners and management companies should therefore check now, in particular, whether their systems meet hygiene requirements.

Focus on Legionella: Origin, Transmission, Risks                                               

Legionellae are widespread bacteria that usually only become a problem in building water systems once they have multiplied significantly. They thrive particularly well in warm, stagnant water, especially at temperatures between 25 and 45 degrees Celsius. Above 55 degrees, their growth is inhibited, and at 60 degrees or higher, the bacteria die off. This issue therefore comes into focus especially at the start of the vacation season: When apartments or buildings are used only sporadically during the vacation period, water can remain stagnant in the pipes for longer periods. If the water isn’t circulated enough, a biofilm can form inside the pipes, allowing Legionella bacteria to multiply rapidly and spread through the plumbing system. Higher temperatures in the summer further promote their growth. The risk of Legionella infection increases. Property owners and management companies should therefore check now whether their systems meet hygiene requirements. This is particularly relevant when showering: Infection usually does not occur by drinking the water, but rather by inhaling tiny water droplets, known as aerosols. In addition to showers, these can also form at faucets, in pools, or in humidifiers. If Legionella bacteria enter the lungs in this way, they can cause illnesses ranging from mild flu-like symptoms to severe pneumonia (Legionnaires’ disease).

Regular inspections ensure safety                                                                           

For property owners and management companies, drinking water hygiene is not only a matter of precaution but also a legal requirement in many properties. The basis for this is the Drinking Water Ordinance (TrinkwV): According to Section 31, certain building water supply systems must be regularly tested for Legionella spec.—at least every three years in many rental residential buildings.

“Property owners and management companies need to reliably monitor drinking water hygiene—while ensuring that testing requirements cause as little additional effort as possible in day-to-day operations. This is exactly where Techem steps in: We make Legionella testing easier, more predictable, and legally compliant—from clarifying testing requirements to organizing sample collection and conducting analyses in cooperation with accredited laboratories,” says Daniel Groh, Head of Drinking Water Hygiene at Techem. Digital services such as the Quick Check for Testing Requirements and the online calculator further assist property owners and management companies in efficiently organizing Legionella testing and reducing administrative burdens. In this way, Techem enhances safety in residential buildings while also easing the burden of day-to-day administrative tasks.

As the summer vacation begins, the following applies: Those who address drinking water hygiene early on lay the foundation for safe building operations—both now and beyond the vacation period.

Click here for more information on Legionella testing (Only in German available).

Image information: Prolonged absences and empty properties can lead to the proliferation of Legionella. Digital services such as Techem’s “Inspection Requirement Quick Check” and the online calculator help property owners and management companies efficiently organize Legionella testing (Image source: Techem).