Making digging safe

14 May 2021

Until recently, if you were planning construction works that required excavation in Milan, you may have had to add months to your project estimate as the compulsory paper-based process required sign-off from over 40 entities to verify location information of the subterranean infrastructure.

Due to security concerns this information has always been tightly controlled, but the fact that different providers owned different pieces of the subterranean puzzle made it difficult to access or to have an overview. Today, Milan is among the first cities in the world to create a tool that provides a complete picture of the city underground with a wide variety of applications.

The dangers of not knowing what’s under your feet

Under any city’s street and sidewalk hides a maze of cables and pipes residents ignore, until a construction site shows up in front of their building. These ‘underground services’ provide residents with many different services like fresh drinking water, electricity, telecommunications, sewage treatment. Residents might take these services for granted, but, in Milan, they have been put in place and managed by multiple private companies or public services, some of which no longer exist, making it even more challenging to know exactly what is running below a particular intersection.

The sheer number of entities involved meant that construction works necessitating excavation, and therefore required to verify what lies underground, had to be validated by multiple city agencies and private entities, each with their own data, maps, and strategic priorities. This time-consuming sign-off process slowed down key public works and increased the probability of accidents due to misleading or outdated information about vital services, such as the location of drinking water or flammable gas.

Knowledge is power

“So, Milan came up with a project that collects, manages, and combines accurate, up-to-date datasets to improve the speed and reliability of multi-stakeholder projects,” explains architect Bruno Monti, Head of the Geographic Information System Unit from the Information Systems and Digital Agenda Department, at the City of Milan.

In practice, the city has developed a digital tool that maps the information about the cables, pipes and other critical infrastructure that runs beneath the city’s streets. With 17 layers of information about the city’s subterranean networks, this tool will help prevent accidents and reduce delays, and therefore site costs, for future excavation and construction works. The tool also includes information about the built and natural environments on the surface. By including surface-level information, the tool will also enable the city to plan more effectively for the impacts of climate change and save time and money by making it easier to design and execute both public and private works.

“The Underground Mapping service is a key tool for the for Municipality of Milan,” says Roberta Cocco, Deputy Mayor for Digital Transformation and Services to Citizens at the City of Milan. “It saves costs and reduces the risks connected to maintenance and public works. It speeds up the approval processes when excavations are needed, whether it’s done by a public agency or private company.”

For example, if the city is planning to build a new light rail, by accessing the existing utility locations, the city can decrease relocation and protection costs. The Municipality of Milan has historically faced challenges in accessing data on underground utilities and services, as this infrastructure has been managed at a regional level. “This tool, along with a requirement to report changes to these networks to both regional and local authorities, resolves this issue and ensures access to up-to-date information,” says Monti.

Developed with inputs from users

From the start this project required a huge effort in coordinating with different agencies and stakeholders, as well as individuals and constructions teams to make sure all relevant actors were involved in the development of the digital tool. By involving everyone from the start Milan collected valuable feedback and insight that ultimately allowed the city to identify specific needs and bottlenecks to be improved.

Throughout the design process, the municipality ran workshops to exchange feedback with users, establishing a constant direct communication channel with them, collecting their suggestions, and improving the model. “We ran joint sessions to analyse and evaluate user experience with people from the utility companies,” says Monti. “As a result, we added some functions, like developing a custom interfacing with external software commonly used by them.”

Driven by the Department for Geographic Information System the collection and management of geospatial data for the digital tool was initially done from many mostly paper-based sources, including the municipality’s historical records. Once most of the existing data was digitalised, it became essential for the municipality to guarantee that the data would stay updated and relevant as new construction work was made within the city.

The city organised a training campaign as soon as the prototype was functional, making sure that anyone involved in the excavation process would be able to use the system to obtain all necessary permits, and to input the new information in the database. Depending on the size of their sites, contractors followed a two-months long training to learn how to use the digital tool. At the beginning of 2021, more than 500 people had been trained to use the platform.

More data, more protection

This project does not stop at subterranean information, it brings together this data with surface level data. The surface level data includes administrative and statistical boundaries; transportation routes and zones, like public transit lines, bike lanes, and pedestrian areas; and environmental data, like daytime land surface temperature.

The additional information allows the city to run sophisticated analysis on how surface level infrastructure and zoning interact with underground assets. And the tool will become a regular part of planning processes in Milan with additional data and functionality to be created as more needs arise.

“In the future, the tool will be expanded with other Geographic Web Applications,” says Monti. “For example, public events, electric charging infrastructure, or traffic control plans.”

This of course also means that there is a lot of data that is collected and managed by the digital tool. Some information, like that relative to underground services, raises public security concerns and needs to be restricted. In accordance with GDPR rules, the data is confidential and protected. Only the city has access to the entire Utility Data Repository, and secure, approved access to the mapping system itself is in place to make sure the right people have access to the right data.

Who’s next?

The project might be only in its beta release, but it has already scored some points. The administration has already saved 45 minutes per digitalised procedure and 5.4 million pages compared to the old system. Users saved even more time through use of the digital tool – an average of 214 minutes per procedure are now saved. The digital tool also resulted in a 10-20% cost saving.

“This tool showcases the level of digitalisation Milan has achieved,” says Cocco. “The most impactful aspect of the project is the use of technology applied to services that the municipality already provides, as well as those that will be implemented in the future, reinforcing the city’s operational framework and preparedness for future challenges.”

Cities around the world face similar challenges to maintain reliable digital information about underground and above-ground utility services, and Milan is already inspiring nearby cities. Turin and Genoa have shown interest in replicating this model and are in touch with Milan to study how best to implement it in their cities. So, if your city is also struggling with a lengthy process before contractors can start digging in all safety you might want to give Milan a call.

* Bloomberg Associates helped to conceive the digital mapping tool together with the City of Milan’s Resilience Team. The main team working on this project is the Department for Territorial Information Systems –the GIS Unit of Milan– assisted by the ‘Underground Services Unit’ within the Mobility Department and designated members of the Municipal Police, who are involved each time an excavation is done on public land. The project is implemented by the Analytics Division of the Information Systems and Digital Agenda Department in partnership with other Departments of the Municipality of Milan. Read more about Milan’s digital solutions.


Wilma Dragonetti Eurocities Writer