Key takeaways
- There is no honest single price per kilometre. The cost depends far more on the cable route than on the instrument.
- The cable is the biggest swing factor. Spare fibres in an existing cable are the cheapest source, a cable laid in the trench of a new pipeline adds a modest amount, and digging a new trench for an existing pipeline is usually the largest single cost.
- Interrogators, station works, software and commissioning follow route length and performance targets.
- Count lifecycle costs, such as support, cable repair and tuning, and not only the supply price.
Why a price per kilometre misleads
Ask three suppliers for a DAS price per kilometre and you may get three numbers that cannot be compared. One may cover only the instrument. Another may include cable, installation and software. A third may exclude the work that matters most on your route. The figure is meaningful only against a stated scope, so the first job is to compare what is included, not the total.
It helps to break the cost into the parts below, and to ask of each quote which parts it covers. If you are new to the technology, our guide to fibre optic sensing for pipelines explains how a DAS system is put together.
The main cost drivers
These are the elements to look for in any quote, and what moves each one.
| Cost element | What drives it | How it scales |
|---|---|---|
| Fibre cable and route | Spare fibre in an existing cable, new cable in a shared trench, or a new dedicated trench | Per kilometre of route; the largest variable |
| Installation | Trenching, burial depth, distance from the pipe, ground conditions, access and any work in hazardous areas | Per kilometre; strongly site-dependent |
| Interrogator units | Route length, reach per unit, number of channels, and whether DTS or DSS is also needed | In steps: one unit covers a section of route |
| Station works | Housing, power, cooling and communications back to the control room at each interrogator site | Per station |
| Software and integration | Event classification, alarm management, interfaces to SCADA and historians, and licensing | Mostly per system; some suppliers licence by route length |
| Commissioning and tuning | Site noise survey, threshold setting, test events and operator training | Per project; grows with route complexity |
| Support and lifecycle | Software updates, spares, cable repairs and periodic re-testing | Every year, over the life of the system |
The cable: the cost that swings most
Fibre sensing uses the cable itself as the sensor, so where the cable comes from sets most of the project cost. Three situations cover most pipelines.
| Situation | Incremental cable cost | What to check |
|---|---|---|
| Spare fibre in an existing cable | Lowest | Spare fibres in a telecommunications cable already on the route. Check the cable’s condition and routing, who owns it, whether the fibres are in use, and a test trace of the fibre before committing |
| New pipeline build | Moderate | Sensing cable laid in the pipeline trench. The trench is already being dug, so the extra cost is mostly cable and installation time. Lay the cable close to the pipe for better coupling |
| Retrofit to an existing pipeline | Highest | A new dedicated trench. Trenching, reinstatement, permits and landowner agreements usually dominate the project |
This is why the same DAS technology can look inexpensive on one pipeline and expensive on another. It is also why fibre sensing is most economical when it is designed in from the start of a new build.
How performance targets move the price
What you ask the system to do changes the design, and so the price:
- Which events. Detecting digging near the line is a different task from hearing a leak. Leak detection by DAS needs the cable close to the pipe and more analysis.
- Which techniques. Adding temperature or strain sensing needs more instrumentation, and different fibre types: DTS commonly uses multimode fibre, while DAS and DSS use single-mode. A multi-fibre cable can carry both.
- How fast, and how far from the cable. Tighter response times and wider detection distances raise processing and design effort.
- How available. Redundancy, such as a looped fibre or dual interrogators, adds cost but keeps coverage after a cable break.
Costs that sit outside the supplier’s quote
- Land access and permits along the route.
- Communications and power to each interrogator station, if they are not already available.
- SCADA integration. Bringing alarms into the control system operators already use, with clear response procedures behind them.
- Tuning over time. Site-specific noise is the usual cause of nuisance alarms, and conditions on a route change.
- Response. Someone must act on alarms, so decide who and how before commissioning.
One cost that is often lower than expected is the field itself. The sensing fibre is passive, with no power or electronics along the route, and interrogators can sit in safe areas, which simplifies work near hazardous areas.
Comparing DAS with the alternatives fairly
Weigh the cost of a DAS layer against the consequence of what it addresses and against what you spend on patrols and surveillance today. Third-party excavation damage is a well-documented cause of pipeline incidents, and DAS is one of the few technologies that can warn while the digging is happening.
Comparing it with computational pipeline monitoring needs care. CPM uses instruments you already have, so its hardware cost is low, but it may need instrument upgrades and modelling effort, and it cannot see interference before a leak. The two address different threats, which is why many high-consequence pipelines use both. See RTTM vs fibre optic leak detection for the comparison.
What to prepare before you ask for a quote
A supplier can give a meaningful budgetary figure only with the facts below. They also let you compare quotes like for like.
- Route length and a chainage plan, with road and river crossings marked.
- Whether the pipeline is new or existing, with burial depth and trench plans if it is new.
- Any existing cable on the route: type, fibre count, fibres in use, age, any test results, and who owns it.
- The events you need to detect and how quickly you need an alarm.
- Possible interrogator locations, with power, communications and access at each.
- Hazardous-area classification for any work or equipment in the field.
- The control system interface: protocol, alarm philosophy and where alarms must appear.
- Redundancy requirements and the support you expect over the system’s life.
If you would like to talk through a route, see our fibre optic sensing page or contact our team.
Frequently asked questions
How much does DAS cost per kilometre?
There is no reliable single figure. The spread between using a spare fibre and trenching a new route is very large, and supplier quotes often cover different scopes. Compare what each quote includes, using the cost elements in this article, and give suppliers the route facts they need for a budgetary estimate.
Can DAS use existing fibre optic cable?
Often it can, if there are spare single-mode fibres along the route in suitable condition and the cable follows the pipeline closely enough. The cable’s condition, routing and ownership all need checking first, and distance from the pipe affects what the system can detect.
Does DAS need power along the pipeline?
No. The sensing fibre is passive, so there is no power or electronics along the route. Power and communications are needed only at the interrogator stations.
What are the running costs of DAS?
Mainly software and support, spares, periodic re-testing, repair of any cable damage, tuning as conditions on the route change, and the time operators spend responding to alarms.
