Drinking water network · Hygiene
Mains disinfection for drinking water networks in Vienna, Lower Austria and Burgenland
A main that has been excavated, renewed or out of service for a longer period does not go back into the network without hygienic evidence. CFT disinfects drinking water mains with hydrogen peroxide: a 50 per cent concentrate is used, which is diluted on site to the application concentration set for the section and introduced into it. The treatment leaves no residues and impairs neither taste nor odour. On request we disinfect with sodium hypochlorite or chlorine dioxide. We work for this in Vienna, Lower Austria and Burgenland – a short journey, appointments at short notice and local knowledge of the supply area. Report the section on +43 (0) 2252 53169 or in writing to office@cft.at, and we will settle the agent, the discharge and the appointment.
What we do on site
We treat the section that was newly laid, opened or microbiologically conspicuous, from the pre-flush through to the final flush. We do not begin without the discharge of the flushing water settled, and we do not lay or repair the main itself. Whether microbiological sampling is additionally carried out before the return to service is settled by the network operator; the sampling is not part of our service.
Key facts at a glance
| Methods | Disinfection with hydrogen peroxide (50 per cent concentrate, diluted on site), sodium hypochlorite or chlorine dioxide on request, flushing, discharging and residual measurement |
|---|---|
| Application range | Newly laid and existing drinking water mains in municipal and industrial networks |
| Duration | Section by section, depending on length, nominal diameter and contact time |
| Result format | Documentation on request |
| Service area | Vienna, Lower Austria and Burgenland |
For water suppliers
The occasion is usually one of three: a newly laid section before commissioning, a main after a repair opening, or a pipe run after a microbiological irregularity. Treatment with hydrogen peroxide avoids the impairment of taste and odour caused by chlorine-based products, and with it the complaints from the supply area. Both new and older existing pipes are treated.
For you as a business
For pipeline contractors, disinfection is the step that completes the handover once the pressure test has been passed; it can be described as a separate tender item by length and nominal diameter and can be commissioned together with the pressure test as a package. Industrial drinking water networks, works mains and installations in individual buildings need the same evidence; what has to be settled in advance is the discharge of the flushing water and the coordination with network operations.
How the job runs
1. Settle the section and the discharge. It is determined which pipe run is treated, where the agent is fed in and drawn off and where the flushing water may be discharged. Without a settled discharge the measure does not begin.
2. Pre-flush. The section is flushed so that sand, drilling swarf and residual dirt are removed. Deposits shield germs, which is why disinfection of an unflushed main works only incompletely.
3. Introduce the disinfectant. The main is filled with the prepared solution and the agent acts over the intended period. During this phase the section stays isolated and marked so that no water is drawn off.
4. Flush out and measure the residual. The section is then flushed out completely and the agent is discharged properly. After the final flush, the residual of the disinfectant is measured before the main goes back into service.
Equipment and methods
Disinfection with hydrogen peroxide
Hydrogen peroxide is used as a 50 per cent concentrate, which is diluted on site to the application concentration set for the section. What goes into the main is therefore a strongly diluted solution, never the concentrate: the latter is a hazardous substance, strongly oxidising and corrosive. Hydrogen peroxide acts against bacteria, viruses and biofilms and breaks down into water and oxygen, which is why the treatment is regarded as leaving no residues. It acts where it reaches: coated pipe walls, dead legs and branches with no flow have to be flushed beforehand or included.
Disinfection with sodium hypochlorite or chlorine dioxide on request
On request we disinfect with sodium hypochlorite or chlorine dioxide, in compliance with the respective safety and environmental requirements. The disadvantage is at the same time the reason hydrogen peroxide comes first: chlorine-based products impair taste and odour.
Flushing, discharging and residual measurement
The treatment does not end with the contact time but with complete flushing out. That the agent has been removed is evidenced by the measurement of the residual in the flushed section; this is why the discharge is settled before the start and not improvised during the measure.
What you receive
The service is the disinfection itself; documentation is available on request. We do not lay or repair the main itself, and we do not carry out microbiological sampling.
Costs and effort
The effort depends on the length and nominal diameter of the section, the method chosen, the number of feed and draw-off points and the discharge situation. We agree the cost range with you by telephone before the job, ideally together with the pressure test.
Frequently asked questions
Why hydrogen peroxide instead of chlorine?
Because it breaks down leaving no residues and causes no impairment of taste or odour – the most noticeable difference in the supply area. On request we disinfect with sodium hypochlorite or chlorine dioxide.
Can older existing pipes also be disinfected?
Yes. On older mains the pre-flush is particularly important, because deposits on the pipe wall shield the agent; heavily coated pipe runs need more flushing effort.
How long is the main out of use?
For as long as the contact time, the final flush and the evidence before release take. The section stays isolated and marked; the period is planned and announced in advance.
Does the disinfection replace the pressure test?
No. The pressure test proves that the section is tight, the disinfection that it is hygienically sound.
Contact and opening hours
For sections in Vienna, Lower Austria and Burgenland: CFT Group GmbH, Wiener Straße 99, A-2514 Traiskirchen, +43 (0) 2252 53169. Monday to Thursday 8:00–16:30, Friday 8:00–12:00. Outside office hours in writing to office@cft.at; we will come back to you on the next working day.
Related services
Describe the findings.
The more precisely you describe the findings, the more directly we can go to work. Plans, readings and photos help us settle the method in advance.
What happens next
- We read your message and match the case to a method.
- We come back to you – usually with a question that shortens the appointment.
- We confirm the appointment and what it costs before anyone sets off.
Rather talk?
+43 (0) 2252 53169
Mon–Thu 8:00–16:30 · Fri 8:00–12:00
Describe your case.
Fastest by telephone – then we settle straight away which method fits and what you should prepare.
Outside office hours, write to office@cft.at.