OGC Underground Infrastructure Concept Study Engineering Report

Every year the vast majority of seemingly routine street excavations occurring around the world are adversely impacted by lack of usable information about buried utility infrastructure. A project is delayed for days and weeks at a time to figure out where utilities are buried so work can be planned and performed without undue risk. A work crew replacing a sewer line accidentally or unknowingly strikes a gas main, causing a leak and the threat of an explosion. A large-scale construction project is stalled for months, incurring delay claims and change orders that significantly increase costs, because the locations of utility installations were never properly recorded or depicted and were later found to obstruct planned foundation work. Contractors, in response to onerous contract liability language, increase bid costs by a minimum of 10-30% for contingencies to deal with buried unknowns.

What these kinds of events have in common is that they all can be prevented if accurate, comprehensive utility and soils information are available for rapid integration and analysis. An essential first step toward achieving this capability involves developing geo-enabled utility data models with built-in tools for enabling data interoperability and integration.

To address these challenges three organizations sponsored a concept development study for underground information with a main outcome being this Engineering Report. The visionary sponsors of the OGC Underground Concept Development Study were:

• The Fund for the City of New York - Center for Geospatial Innovation
• The Singapore Land Authority
• Britain’s National Mapping Agency, Ordnance Survey

The distinguishing and most powerful aspect of geo-enabled data is that it can support integration and interchange of any number of disparate datasets based on the common organizing principles of geospatial location, extent, and connectivity. Geo-enabled data can not only be integrated within a locality, but also across geographic and jurisdictional boundaries to encompass entire regions, countries, continents, even global extents. The stakes are very high to get models for geo-enabled data right. The mission of the Open Geospatial Consortium (OGC) has been since 1994 to promote data standards that allow geo-enabled data to be created, shared, and integrated seamlessly for many different domains and applications. OGC standards cover a wide variety of geodata types including natural features above and below ground as well as surficial components and infrastructure of the built environment.

Up until recently, OGC standards had not yet begun to address data associated with underground utilities such as water, sewer, gas, electricity or telecommunications. Neither had the standards really encompassed aspects of the urban underground environment such soil characteristics, bedrock geology, near-surface hydrology, and built components such as foundations and pilings. Data of these types, if collected at all, is characterized in most jurisdictions by isolated silos of incompatible information with different levels of accuracy and formats, making it challenging if not impossible to integrate data across the various utility networks typically entangled under most city streets. The need to improve this situation is clear.

This report documents the progress made to date by OGC and its members to build a complete picture of the present situation and develop a conceptual framework for action to improve underground infrastructure data interoperability. The report also identifies the most important steps to be taken next in order to develop the necessary data standards and foster their adoption.

Beyond their own intrinsic value, common underground geodata standards may also serve to connect many existing data models and datasets associated with urban environments, making it possible to analyze and model them in ways never before possible. This holds enormous promise for the advancement of our society and achievement of smarter, more livable cities.

The following normative documents are referenced in this document.

For the purposes of this report, the definitions specified in Clause 4 of the OWS Common Implementation Standard OGC 06-121r9 shall apply. In addition, the following terms and definitions apply.

Over the past decades, Geospatial Information Systems and Technologies (GIST) have gained recognition as valuable tools that support a wide variety of essential operations and functions. Much of the power of GIST systems is based on their exceptional ability to integrate, visualize and analyze multiple data sets, by correlating them in space and time through the use of common location fields such as addresses and GPS positions. A significant part of the large-scale success of GIST is due to efforts, led by the Open Geospatial Consortium (OGC), to establish standards for geo-enabled information that facilitate data interchange and integration. Such standards make it possible for spatially enabled data to be accurately superimposed from many sources within a single area and connected across many adjoining areas.

Utility infrastructure data – both above and below ground – presents a significant challenge to the establishment of common spatial data standards and is a “last frontier” of sorts for the geospatial revolution. Within any metropolitan area there may be as many as eight or more different utility infrastructure and networks including: water supply wells, potable and treated water, sanitary sewer, storm drainage, irrigation, natural gas, steam, traffic management and control systems, raw and refined petroleum and chemical product pipelines as well as electric power and telecommunications lines. These networks often include or are part of an array of transmission, distribution and service lines. In addition, there are all of the tracks, tunnels, bridges, conduits, and other structures that make up transit systems. Each utility network or system is often independently owned and operated by a distinct public or private organization which has unique engineering and technical characteristics and practices, along with particular data management needs, that have become established over many years. Unique manual record keeping systems have evolved over time into disparate, isolated digital systems with incompatible software and data formats, and schematic level spatial representation. Even different areas or systems within a single utility franchise may use distinct and incompatible ways of recording, managing, and depicting information. These incompatibilities make efficient and timely data integration across different utilities difficult and imprecise. Even when it is technically possible, utilities have often been reluctant to share their information for security, competitive and cultural reasons.

Above-ground infrastructure is at least straightforward to re-survey and validate. When infrastructure networks run underground, the problem of data incompatibilities is compounded further, because the structures themselves are invisible, covered over by street pavement and sidewalks, encased in different soil and sediment units, and entwined with other utility infrastructure. For many features, especially older sewers and water mains, the exact locations are not even known, having been referenced to curb lines and sidewalks long since vanished. Even less well known is the underground context of such structures, including soil conductivity, buried conductors (causing distorting or misleading electromagnetic fields), chemicals, moisture, heat, cold, geological faults, subsidence, vibration, and so on. The presence and effect of water, whether as groundwater, seepage, or infiltration, is not only significant, but dynamic and can follow a complexity of permeable paths which are difficult to identify and monitor. Most problematic of all, interactions between utility systems are often unknown; for example, the failure of one item, such as a transformer, can cause a dewatering pump to fail, which may cause a telecom vault to flood, etc. The potential for such cascading failures need to be understood in advance to develop appropriate counter measures to safeguard the resiliency of our utility infrastructure systems.

The problem would be more tractable if underground infrastructure networks never needed repair, maintenance, or replacement but in fact the exact opposite is the case. Across major cities like New York and London, hundreds of thousands of street excavations are done each year to fix, replace, or update infrastructure, as well as add new services where older infrastructure already exists. Ordnance Survey has collated existing research that indicates that approximately 4 million holes are dug each year by the United Kingdom (UK) utilities industry to repair, upgrade or provide new connections to their assets .

At the present time, few if any cities have been able to comprehensively collect and integrate data about the underground infrastructure networks that serve their citizens. Drawings of underground utilities projected onto the street surface are regularly created on a piecemeal basis, from a broad range of data sources, nearly all of which is non-standardized. The resulting composite drawings present depictions of infrastructure which vary greatly in reliability. To reduce the likelihood of hitting utility structures during a street excavation under these circumstances, “Call 811” notification services (such as, “One Call” and “Dig Safe”) were implemented to alert utilities of an ensuing excavation zone. Often the excavation limits are marked on the street itself, and each utility owner must send a representative or their contract locating service to visit the location and physically mark the location of their own lines on the same street surface. Alternatively, personnel from one utility must visit the map/drawing rooms of other utilities to do visual comparisons of structure location. Call 811 was established as a damage prevention service, and essentially provides a utility owner a last resort for protection; the process is reactive in nature, performed 24 to 48 hours prior to excavation, and not timely enough to allow proactive and predictive utility engineering measures such as advanced utility coordination, conflict analytics, and conflict resolution engineering as promoted by the American Society of Civil Engineers and Federal Highway Administration. Manually intensive methods, such as utilizing Call 811 to acquire and integrate utility information, add time and uncertainty to the construction process, especially given the highly variable quality of utility records, which are commonly a mixture of old, spatially inaccurate, incomplete, and non-standardized information

The Ordnance Survey’s Geovation Challenge 2016 has collated information from many different sources and reports that “Approximately £150 million is incurred by strike damage to third party assets alone by utilities across the UK with indirect costs around ten times this. Fatalities are a severe consequence, with for example, approximately 12 deaths and 600 serious injuries per year from contact with electricity cables. Furthermore, In emergency situations, the inability to quickly and accurately integrate quality data from multiple utilities can result in greater damage, larger outages and unnecessary injuries and deaths.”

Currently, the different utilities in most jurisdictions keep their infrastructure records (surface as well as underground) in a variety of formats that are not easily integrated. Moreover, utilities are reluctant to share with each other anything more that the barest information because of security and competitive concerns. This inability and reluctance to share data heightens the challenges of utility “strike” avoidance; acquisition of high-quality information for large-scale planning, design and construction; and emergency and disaster preparedness and response. Additionally, the lack of accurate and integrated infrastructure data impedes efforts to use new sensor and control technologies that characterize “smart” cities and counties, with their promise of greater efficiency and improved quality of life. This is an appropriate task for the OGC because the most effective way of representing utility networks is through geospatial visualization and analysis, and the best way of integrating different geospatial networks – and unlocking the power of data combinations - is through the adoption of compatible geo-data models that allow utilities operating in the same area to bring their data together- with utility feature location as a primary organizing and integrating principal - in ways that maximize functionality and collaboration.

Accurate three-dimensional geospatial information about the location, nature, condition and relationships of these assets would reduce the expense for the asset manager and other stakeholders. Holistic understanding of the relationships between underground assets and with above ground infrastructure would help minimize service breakdowns and mitigate the impact of disasters. Comprehensive, exchangeable and up-to-date datasets could benefit the following business and societal activities:

These benefits would be realized by enabling a variety of efficiencies:

Numerous studies around the world have shown that these are common challenges in an increasingly urban and technical world. Through the Underground Infrastructure initiative, OGC and its members seek to lower the barriers to interchange and integration of infrastructure data in a number of critical applications. By means of a common, extensible data model and interchange standards, OGC expects to create a favorable environment that encourages uniform, high quality data development and enables straightforward, timely data integration. This will eventually make it possible to assemble complete “common operating pictures” of what is underground whenever and wherever needed. This should lead to large-scale efficiencies in the way that the “underground city” supports the life of a city as a whole.

Subsurface and below ground utility networks: A common data model for underground infrastructure will need to represent all the components necessary to characterize that infrastructure as a whole in order to enable infrastructure data interoperability and standards formation. Such components will at a minimum include or cover the following.

Surface and above-ground utility networks: The primary purpose of this project is to develop interoperability standards for underground infrastructure data in urban environments. In doing this OGC recognizes the need to look towards developing interoperability standards as well for infrastructure networks and features that run on or above the ground. Such above-ground utility networks are present even in dense urban areas but are more often found in suburban and rural areas.

Rural and suburban areas: It is the hope that this project will initiate and facilitate a process by which infrastructure interoperability standards are developed that encompass the characteristics of all kinds of utility networks located in all types of areas. From the standpoint of urban infrastructure, this is important because the supply chains of many types of utilities involve the transmission of resources from generation plants, wells and reservoirs located outside urban areas. Additionally, having infrastructure interoperability standards that cover every kind of community will enable regional planning efforts that examine infrastructure not as isolated islands of urban use, but as interdependent parts of a regional whole.

The OGC Innovation Program utilizes a multi-step collaborative methodology for interoperability initiatives that seeks to uncover geospatial interoperability challenges and then develop ways to address them. The methodology begins with a Concept Development Study (CDS) in order to understand and frame the current state of information technology in a target knowledge domain. A critical step in a CDS involves gathering insights from domain experts and other stakeholders about productive future directions that can then be explored in subsequent initiative activities such as testbeds, experiments, and pilots. Ultimately the initiative methodology leads to development and adoption of consensus reference architectures and information standards that increase both the value and the utility of geospatial information.

The Underground Infrastructure Concept Development Study (UICDS) is based upon responses to a Request for Information as well as results of a 2-day workshop and other inputs. The study examines opportunities for–and barriers to–establishing functional three-dimensional repositories of underground infrastructure and other relevant sub-surface information. The study will consider, among other issues, how different infrastructure data providers, consumers, and software vendors can best achieve:

The CDS will also outline the scope of a multi-phase underground infrastructure interoperability initiative. Subsequent phases will seek to develop a deeper understanding of implementation and policy issues, as well as test standards-based components for enabling infrastructure data interoperability in realistic application scenarios. Scenarios will initially focus on urban landscapes but will take suburban and regional environments into consideration as well.