Metropolitana Milanese chooses iSM™ Lift & Shift for a Leak Detection Assessment in Milano











The Client:

Metropolitana Milanese S.p.A. is one of the largest and most diversified engineering companies in Italy, with an increasing presence on an international level, capable of providing tailor-made solutions in the design and upgrading of urban ecosystems. MM are partners of institutions, managing authorities and state-owned enterprises that operate in the sector of infraestructure, large-scale construction, network and service design and planning. 

MM is acting as a water company to manage the service and the infraestructure in the City of Milano.

The Problem:

In common with many water companies which have to serve large and highly-populated urban areas, Metropolitana Milanese has an extensive water network, with a primary distribution network comprising of large pipelines going from urban areas to the city centre, and it is difficult to manage, particularly the aspect of leaks.

As an innovative and forward-thinking water company, MM wanted to have the first experience using CRALEY Group's iSM technology for leak detection in one of their crucial water arteries in the heart of Milano. In order to discover the condition of the pipeline itself and to evaluate the iSM™ solution of CRALEY Group.


The pipeline was a 350mm section of an aged 500mm steel pipe where they have experienced several leaks and bursts in the last months and years. This was the reason why the technical team of MM were considering to schedule imminently a full re-lining or replacement of the pipeline section located in San Siro's district.

The Solution:

iSM™ Lift & Shift is the most innovative and advanced system that allows Water Companies to undertake temporary deployment auditing of pipe networks:

    * Detect, map and categorise leaks by severity.

    * Identify service connections.

    * Live-insertion for use in fully operational pipe networks.

    * Transit through valves during audit surveys.

iSM™ under the Lift & Shift basis is the next generation temporary analysis tool that uses Distributed Sensors, via fibre optics used as a specially designed Sensor Cable, which is introduced live into a water pipe under normal operating conditions.

The fibre-optic Sensor Cable is used as a linear & distributed sensor and, since the fibre is actually in the water pipe itself, it has optimum coupling, with unparalleled sensitivity to events within the pipe. 

The Sensor Cable containing the fibre strand is a single-ended insertion for the temporary analysis and this is achieved using hot-tap/live-insertion and can be undertaken with the pipe in full normal service operation. A drogue/parachute carries the Sensor Cable along the pipe route powered by the flow of water.

Runs of up to 1,000m per pipe audit can be covered, with up to 270-degree cumulative bends along the route. The event notifications is extremely dependable, and event location accuracy is very high with typically down to a 1-metre resolution on the first scan and going down to just a few centimetres on a second scan. Lift and Shift™ auditing is independent of pipe material, size, wall thickness or flow velocity.

The detection capability is used in the Lift and Shift™ to allow the sensing fibre to be treated as multiple and individual "virtual" sensors inside the pipe, by time-slotting the back-scattered light. The iSM™ Analyser Unit can define many thousands of separate "virtual" sensors ( i.e. the virtual sensors may each be defined as <1m apart).

Moreover, one of the most interesting features for the Water Companies comes with the ability to detect at the same time as many leaks as there are along the pipe section that is being inspected getting an approximate severity for each one separately.










The installation

The Results:

The works consisted of two full iSM™ Lift & Shift audits during two different days in Via Benedetto Croce, San Siro, Milano on a 500mm steel

pipeline section of 350 metres and two 90 degree elbows.

The Sensor Cable was inserted at the beginning of each audit without any disruption on the water service. When the cable reached the far end position, the iSM™ Analyser Unit was connected to record and analyse data coming all the sensors virtually deployed along the pipeline with the assistance of CRALEY Group Team.

Moreover, it was simulated several different events including a significant number of leaks with different sizes and locations to show all the features of the iSM™ working under permanent and non-permanent basis and under automatic or manual mode. 

In three different locations were simulated all the events and all of them successfully detected: 

    - Leaks from 2.5mm, 5mm, 7.5mm, 10mm, 12.5mm, 15mm, 17.5mm and 20mm orifices.

    - Pressure hammers.

    - Lateral connections (big service connection).

    - Human walking.

    - Human activity inside the manholes.

    - Valve operation in the lateral connection.

Finally, after just a few hours per day, the Sensor Cable was lively pulled back leaving the pipeline in the original situation and condition.

CRALEY Group Team using the iSM™ solution after the objective and rigorous analysis done ended proving that there were no leaks greater than 0,1 l/s on the pipeline section during both days were the audit was done.

The high-quality analysis about the pipeline condition has allowed MM to postpone an already scheduled re-lining service on that location saving costings and being able to focus on other pipelines with much more urgencies or operative challenges. 


Caption of the software detecting a leak

The Testimonials:

"iSM™ works in a very unique and different way over all of the existing technologies that we have used and considered. It's very clear that the results, due to how they're obtained, are far way from other solutions in the market.

We have been hugely impressed with all the features proven as an addition to the pipeline audit and the accuracy of results. It has allowed us to reschedule some works prioritizing others to be much more effective in terms of operations and economically too.

We're working together with CRALEY Group to deploy more of their solutions in very different pipelines for leak detection under different basis according to our necessities and strategies."

Massimiliano Vidiri, Direzione Acquedotto at Metropolitana Milanese

"This inspection was the first one done in Italy with our iSM™ solution working under a non-permanent basis. It has fully proved the enormous advantage of a true in-pipe leak detection System who is able to scan and monitor the full length of the pipeline at the same time even under the Lift & Shift option in front of all the others technologies available in the market.

Moreover, it shows how it's helping the water companies to save money with the very accurate location and detection of the leaks, but prioritizing how urgent is to execute some already planned works on a pipeline or to schedule new ones.

We're very happy with our first experience in Italy working with and for Metropolitana Milanese. It has been a great experience to collaborate and to work together with all the great professionals that MM has. 

CRALEY Group is confident about all the unique benefits of our solutions working under permanent and non-permanent regime depending on the customer requirements on each scenario and pipeline. This is the reason why MM and CRALEY Group are already working together in new projects."

Joan Vilaseca, Director-General at CRALEY Group

CRALEY UK Headquarters

Abbey House

282 Farnborough Road, Farnborough,

Hampshire. GU14 7NA.

United Kingdom

Contact Numbers:

UK Telephone:  +44  (0)1252 962 111

UK Fax:             +44  (0)1252 962 123

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