Drinking water network · Loss analysis
Water loss analysis for water networks in Vienna, Lower Austria and Burgenland
A network is losing water and nobody knows where. Water loss analysis answers the question of volume first: how much is being lost and in which section. CFT records the consumption volumes over days to weeks, classifies consumption and loss volumes and narrows the later pinpointing down to a few segments instead of the whole local network. The service is offered in Vienna, Lower Austria and Burgenland; the specialist measuring equipment and the evaluation we provide ourselves. Report your suspicion on +43 (0) 2252 53169 or in writing to office@cft.at, and we will settle the size of the network, meter data and the appointment.
What we do on site
We form the zones together with the water supply manager and evaluate the minimum night flow per zone over days to weeks; if the base load stays elevated, we divide the zone further by closing off step by step. Where exactly the main is defective is not what this measurement says. We name the conspicuous segments in order of priority, so that fine location starts there.
Key facts at a glance
| Methods | Long-term recording of consumption volumes, segment delimitation via gate valves and zones, classification of consumption and loss volumes, leakage profile as the basis for prelocation |
|---|---|
| Application range | Municipal distribution networks, association mains, industrial site networks, fire mains |
| Duration | Recording over days to weeks, depending on the size of the network. |
| Result format | Documentation on request |
| Service area | Vienna, Lower Austria and Burgenland |
For water suppliers
You see the loss in the annual balance, not in the street: the volume fed in does not match the volume billed, the service reservoirs take longer to refill at night, the pumps switch more often. The analysis turns this into a reliable statement – which segments take up an above-average amount of water and which are unremarkable. This lets you justify a rehabilitation plan and set the order of the location work.
For you as a business
Industrial site networks, fire main rings and association mains have the same question, but different conditions: production shifts distort night-time consumption, and some works areas may not be isolated; the zoning is therefore agreed with your site operations management in advance. For tenders the analysis is an independent item that can be costed separately from the location work. What is assessed is the minimum night flow (MNF) for each zone; the classification follows the water balance methodology of the rules – in Austria the ÖVGW rules on water losses.
How the job runs
1. Review the network documents. You provide the plan of the mains, the zone overview, meter data and the volumes fed in over the last months.
2. Set up measuring points. Together with the water supply supervisor, zones are formed and the recording points are defined. For the duration of the measurement the agreed valve positions stay unchanged, otherwise volumes migrate between the zones.
3. Record over days to weeks. The consumption volumes are recorded over a longer period so that weekday, weekend and night-time patterns become comparable. A single day of measurement is not enough for that.
4. Evaluate and hand over. Consumption and loss volumes are classified and the segments in the leakage profile are put in order of priority. The handover is in writing and in a meeting.
Equipment and methods
Long-term recording of consumption volumes
What is measured is not a state but a pattern: over days to weeks the consumption volumes for each zone are recorded. What counts is the minimum night flow – a segment is conspicuous if its base load does not go to zero even without draw-off. If it stays elevated, the zone is divided further by closing valves step by step (step test). The measurement says that water is being lost, not why.
Segment delimitation via gate valves and zones
A network is divided by valve positions into sections that can be observed individually – permanently as a district metered area or temporarily for the duration of the analysis. The precondition is that the gate valves are free-moving and close tight; this is where the delimitation often fails, which is why valve exercising and maintenance is often the more sensible first job.
Classification of consumption and loss volumes
The classification follows the water balance methodology of the rules – in Austria the ÖVGW rules on water losses – and separates billed consumption, own use, apparent losses from meter errors and real losses. Apparent losses act like real ones in terms of volume and have to be eliminated in discussion with the operator.
Leakage profile as the basis for prelocation
The profile determines the order in which segments are searched acoustically. Without this preparatory work the search through the local network is blind – every street is equally suspect, and the effort multiplies without the chance of a hit rising. With the profile the order is settled, and the pinpointing starts where the volume is missing.
What you receive
The service is the measurement itself; documentation is available on request. We tell you where the pinpointing should start. CFT does not excavate and does not repair.
Costs and effort
The effort depends on the size of the network, the number of zones and the recording period; no two networks are alike. We agree the cost range with you by telephone before the job. Unlike leak detection in a building, no buildings insurance applies here, because this is about your own infrastructure.
Frequently asked questions
Is one night of measurement not enough?
No. A single night value can be distorted by a fire-fighting draw-off, a reservoir being filled or a large consumer; only the comparison over days to weeks shows whether the base load is permanently elevated.
Does supply have to be interrupted during the analysis?
No. Measurements are taken, nothing is turned off. If a segment is to be isolated completely, that is planned in advance with you and the consumers affected.
Does the analysis find the leak?
No, and that is the point. Water loss analysis delimits segments; the precise location work then follows acoustically as part of burst location and leak detection.
What if no loss is found?
That is a result too, and it is named as such. If the base load is unremarkable everywhere, the difference in the balance usually lies with meters, own use or unreported draw-offs. The report names which of these possibilities the measurement was able to rule out.
Contact and opening hours
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
Burst location and leak detection in the network
The acoustic pinpointing in the segments that the leakage profile names.
Valve exercising and maintenance
Without free-moving, tight gate valves a network cannot be cleanly divided into zones.
Spring pipeline locating and inspection
When the loss lies upstream of the local network, in supply mains and spring catchments.
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.