Between the Poles

SUE proposed as foundation for best practices for utility coordination on P3 projects

Public infrastructure projects frequently experience delays and cost overruns - often due to underground utilities - but delays and cost overruns are rare on P3 projects. Furthermore because P3 projects include not only the design/build part of the project but also the operate and/or maintain phase, P3s deliver better designed facilities that can be efficiently operated and maintained during the contract term, which can extend from 15 to 30 or more years. To help public-private partnership (P3) project stakeholders develop an efficient and consistent process for coordinating utilities, the Transportation Association of Canada (TAC) has developed a best practices guide specifically targeted on P3 projects. Essential to reducing the risk associated with underground utilities is knowing their accurate, up to date location.  The TAC guide makes subsurface utility engineering (SUE) the foundation for coordinating utilities on P3 public infrastructure projects.

Background

Public infrastructure projects frequently experience delays and cost overruns often due to underground utilities. The reason is that on a typical public construction project the government is responsible for project risks that add time and money to an infrastructure project.

Canada has developed a reputation for successfully delivering infrastructure projects using a public-private partnership (P3) approach. P3s are used to deliver an infrastructure project such as building and expanding roads, bridges, transit systems, and other public infrastructure.

On a P3 project the public sector always owns the infrastructure. The government determines when and where to build the project, its scope, and its budget. A competitive process is used by the government to select a private partner. The private partner designs, builds, finances, maintains and/or operates the public infrastructure. Delays and cost overruns are rare on P3 projects, as this approach allocates risks and responsibilities to the public and private sectors based on their areas of expertise. For example, the public sector bears the risk for changes in laws and regulations and the private partner bears the cost of construction delays. Because P3 projects include not only the design/build part of the project but also the operate and/or maintain phase, P3s deliver better designed facilities that can be efficiently operated and/or maintained during the contract term, which can extend from 15 to 30 or more years.

SUE proposed as foundation for coordinating utilities on P3 projects

There is a trend in legislation and regulation which on one hand may provide strong measures for compelling utilities and other infrastructure owners to improve locating, utility treatments and relocations, on the other provide encouragement for a collaborative approach among utility owners and government agencies which replaces the traditional regulatory mechanisms involving fines and other penalties for noncompliance. On P3 projects in particular the key to successful utility coordination is a team approach, with each member having a role in completing their portion of the project. The players on the team are the project owner, typically a government agency that funds the project; the ROW owner, the government agency responsible for maintaining the public ROW; the Utility Coordinator (UC), responsible for utility coordination on all phases of the project; the designer, who designs the P3 project at different stages ranging from conceptual design through detailed design; and utility agencies, the owners of public or private utility infrastructure who are often also the Project Owner. One of the key challenges for utility agencies is providing accurate records of their existing infrastructure to the Project Owner.

SUE and as-built standards

The foundation for the best practices proposed by TAC for utility coordination is subsurface utility engineering (SUE).  Standard practice for SUE investigations is based on American Society of Civil Engineers (ASCE) 38, first released as ASCE 38-02 but soon to be replaced by ASCE 38-21. The ASCE 38 standard establishes quality levels for underground utility information that all parties can use to evaluate the accuracy and reliability of underground utility location data.

The standards for "as-builts" for newly installed and relocated infrastructure are ASCE 75 in the U.S. and CSA S-250 in Canada.  For example, in Colorado both ASCE 38 and 75 are mandated, which means that every underground and above ground utility segment that's depicted could have either a utility quality level based on ASCE 38 for existing infrastructure or a utility accuracy level from the ASCE 75  "as-constructed" standard for newly installed or relocated utility infrastructure.  In Canada it's a little different. Every utility segment could have either a utility quality level based on ASCE 38 for existing infrastructure or a utility accuracy level from the CSA S-250 standard for newly installed or relocated infrastructure.

Application of SUE over project lifecycle

The TAC guidelines breaks the construction process down into phases: Planning, RFP Document Preparation, In-Market Design, Project Implementation and Post-Construction and identifies the roles and responsibilities of each team member during each phase with respect to utility coordination. The TAC guide describes how SUE practice is allocated over the different phases of the project.

During the Planning Phase the Project Owner is responsible for putting together a base plan of the general construction project area that is adequate for the requirements of utility coordination. The base plan is  forwarded to all impacted Utility Agencies (public and private), with a request for each utility to provide maps of their utility infrastructure based on the Utility Agency’s current records in the proposed project area. This information represents some of the QL-D (from utility records) and QL-C (from site visits) information for the project and is typically of limited quality. It is often  inaccurate, out of date or simply missing, which is frequently he case for abandoned infrastructure. At this stage it is critical that the utility agencies flag high risk utilities such as high pressure transmission lines.  Preliminary SUE investigations, providing QL-B (using remote detection technology) and/or QL-A (potholing), may be completed to validate and improve the quality of the utility information. Based on all of this information the Utility Coordinator creates a preliminary Utility Conflict Matrix that lists potential utility conflicts and relevant information about the utilities identified.  At the completion of the Planning Phase the approximate location of existing utilities and potential future utility infrastructure and possible relocations of high risk infrastructure should be known.

The Request for Proposal (RFP) Documentation Preparation Phase involves preparing the final RFP documents that will be made available to potential bidders. Included in the activities at this stage is the development of a Reference Concept Design (RCD) which may require that additional preliminary SUE investigations be performed to a quality level required for the Project’s In-Market Design Phase. The RCD is used by the Project Owner and Utility Agencies to conduct utility conflict assessments.  If a utility is identified to be in conflict with project works, further SUE QL-A investigations may be required to verify whether it indeed represent a conflict. The RCD design augmented by SUE information plays a significant role in the development of a RCD Utility Conflict Matrix which is a key component of the RFP becausee it provides crucial information about potential utility conflicts to the bidders.

The In-Market Design Phase (or Bid Phase) includes all activities required to deliver a preliminary design which forms the basis for preparing bid estimates.  Starting with the RCD Utility Conflict Matrix, each bidder prepares their own Utility Conflict Matrix based on their RFP submission design.  Knowing the location of existing utility infrastructure is crucial for the bidder to estimate scope of work. To help identify the location of existing utilities – both buried and overhead – the bidders use the information available as background documents provided with the RFP including utility records for private and public utilities, the RCD Utility Matrix, SUE reports provided by the Project Owner, RCD designs, preliminary utility relocation designs from Utility Agencies, and visual inspection and survey information. Since SUE often extends over more than one phase, it is essential to commence SUE investigations early in the Planning Phase to ensure the information is available to the proponents prior to and not beyond the initial In-market Design.  Each bidder is responsible for identifying the location of all existing utilities within the limits of construction, for coordinating any required utility relocations, and all the utility relocation and/or protection work necessary to accommodate utility coordination for the P3 project. During this phase estimating activities may require additional preliminary SUE investigations.  The In-Market Design Phase ends with technical and financial submissions from bidders to the Project Owner. Each submission is evaluated based on a technical and financial assessment and the Project Owner awards the P3 Contract to the successful private partner.

The Project Implementation Phase includes all activities associated with delivering the project from contract award through to completion of construction.

The initial objective of the private partner is to complete the preliminary design to a 30% level. To achieve this requires conducting an additional SUE investigation with the objective of achieving QL-B and QL-A for all underground infrastructure within the project limits.  This is required to ensure that all the required information has been collected to complete the Detailed Design.  This SUE investigation builds on the preliminary SUE information captured during the Planning and In-Market Design Phases.  Based on the complete SUE data the private partner creates a Utility Conflict Matrix that can be maintained and updated regularly to ensure that the latest conflict data is always available to project stakeholders. 

It is also extremely important for each Utility Agency to have access to the latest detailed design and SUE data to enable them complete their relocation designs early in the process. The initial objective of design is to complete the Detailed Design to a level that is sufficient for the utility companies to initiate their respective detailed designs for their relocation work.

After design and during construction, conflicts with unknown utilities may be encountered. It is essential that they be reported immediately to the Utility Coordinator who will initiate a field conflict resolution process. The private partner and the Utility Agencies need to notify the Utility Coordinator at the first indication of a delay to their relocation schedule due to the unknown conflict. The Utility Coordinator is responsible for assessing the impact of the delay on the overall Utility Relocation Coordination Plan and the private partner will follow up to determine the impact on the overall project schedule.

Once relocation construction is completed it is important to ensure that the records submitted for all relocated underground infrastructure are accurate. Utility Agencies are required to prepare “As-Built” drawings to be submitted to the private partner that are compliant with CSA S-250 quality requirements.

Operation and maintenance (O&M) typically represents 80% of the lifetime of an infrastructure facility. In the Post-Construction Phase under a Design, Build, Finance and Operate or Maintain (DBFO or DBFM) P3 model, the private partner is responsible for the operation and/or maintenance of the newly constructed infrastructure for 10 years or more. The O&M responsibility includes all activities necessary to operate or maintain transit facilities, toll roads and other infrastructure.  For civil infrastructure this includes supporting One Call notifications.  An advantage of DBFO and DBFM P3 projects is that it is in the financial interest of the private partner to control O&M costs by optimizing O&M activities.  This includes ensuring that accurate, up to date and complete location data for underground utilities and other infrastructure within the project limits is collected and maintained throughout the project life-cycle.

Application of SUE and as-built standards

During the Planning and In-Market Design (Bid) phases preliminary SUE investigations are conducted to collect and compile underground location data, typically to QL-D and QL-C quality levels. Building on these preliminary SUE investigations, the best practices for P3 projects proposed by the TAC requires the completion of a comprehensive SUE survey that achieves QL-B or QL-A quality levels for all underground infrastructure within the project limits. The TAC guidelines also require that as-builts submitted for all relocated infrastructure be compliant with CSA S-250, which is the Canadian as-built standard, corresponding to ASCE 75, the as-constructed standard in the US.

Conclusion

The guidelines for best practices for utility coordination on P3 projects provided by the Transportation Association of Canada (TAC) makes subsurface utility engineering (SUE) the foundation for reducing the risk associated with underground utilities. The objective of SUE investigations is identifying and determining the accurate, up to date location of underground utilities including abandoned infrastructure. The TAC guidelines also require capturing and maintaining accurate location data for relocated utilities.  Accurate and up to date location data for all underground utilities is critical for controlling costs during the O&M phase, which typically represents 80% of the lifetime of an infrastructure facility.

Digitalizing the as-builting process essential for accurate underground utility mapping

Over the past decades electric, gas, water, and telecom utilities have poured millions into digitalizing the graphic design/work management and GIS/records management processes. But in spite of this the decades-old as-builting process remains marred by manual paper-based processes that have ramifications for industry and society in general. As-builting is characterized by inefficiency that causes critical processes such as outage restoration to require more time than they should and low data quality which leads to incomplete, out of date and inaccurate underground utility records that are responsible for frequent construction delays, injuries and fatalities for workers and the public, and a drag of billions of dollars on national economies.

Dated, paper-based as-builting workflow

One of the biggest and most persistent problems for almost all utilities is the use of paper in the construction as-builting process.  It is a challenging problem that has been with us for decades.  The first post of this blog in February, 2006 discussed this problem and in some respects the as-builting workflow has not changed that much since then.  Over the past decades utilities have spent millions of dollars digitalizing design (CAD) and records management (GIS), but the gap between them has remained filled with paper. The schematic shows a typical design, construction to GIS workflow that's in place at most utilities today. Design is done using a graphic work design system (CAD) in the office that is integrated with a work management system. A paper job packet is sent to the construction crew in the field who attempt to follow the design drawing. More frequently when contractors take the design drawings out into the field, they often find that obstacles, such as existing utilities or other infrastructure even old tram lines or sewer lines, force them to make changes.  After completion of construction paper as-builts are prepared that make their way back to the office to be entered manually into the records system typically a GIS. If the construction crew has had to make some changes, these are supposed to be redlined on the design drawing, but all too frequently the crew simply hit the easy button and check the box that says, "We built it exactly as you designed it." The reality is that 90% of designs change in the field and the changes are rarely recorded. This is a major source of data quality issues and is the chief reason for the general unreliability of utility GIS records. Unreliable underground records lead to construction delays, budget overruns, injuries and even fatalities for workers and the public. 

The as-built workflow is also fraught with inefficiencies because many of the processes are manual.  The result is massive mapping backlogs. Backlogs of 30, 60, 90 days from construction complete to being entered in the GIS are common. The result is that the utility GIS is always out of date and critical processes such as outage resolution require more time than they should. 

If we are to address these issues it is imperative that we improve the way buried assets are designed, constructed, recorded, and managed.

Grid modernization is driving change

As a result of being asked to do many more things than in the past, the grid is being transformed from a centralized to a distributed model. For electric utilities, utility digital transformation is already driven by increased demand for distributed energy resources (DER) such as solar, wind and other renewable technologies. This creates a requirement for an advanced distribution management system (ADMS) which is the intelligence that supports the new distributed smart grid model. These developments are being accelerated due to COVID-19 and the requirement for a more touchless environment for utilities. The bottom line is that for these advanced solutions to provide full value a reliable digital twin of what is out in the field is essential, and right now for most utilities that remains a challenge.

Grid hardening to increase resilience is another major initiative that is contributing to transforming the grid.  When a utility experiences a major storm, flood, catastrophic wildfires, or other natural disaster it has to change its infrastructure plans.  It may have to move overhead wires underground, move transformers out of flood zones, or ameliorate the risk to substations.  The sheer glut of aging infrastructure replacement programs is also increasing pressure on utilities and contributing to a significant increase in construction activity. Grid transformation on this scale with the sheer volume of new construction that it required is forcing utilities to find ways improve productivity by managing construction data from source to consumer digitally.

As-builting remains a persistent problem

However, a major source of construction inefficiency remains. Why, after decades of growing awareness of the inefficiency and data quality issues associated with the traditional as-builting workflow, are construction as-builts still recorded on paper ? First of all, there's resistance to change. Utility construction is managed using a variety of manual, paper-based processes that have been in place for decades. Secondly, there's the aging construction workforce that has always relied on legacy processes and has not seen reason to change. Another problem is that well-established enterprise systems such as asset management and GIS don't provide the comprehensive solution that construction crews need to digitalize the full process. Those systems are designed to support long cycle construction projects which typically require a month of planning and may not be completed for six, nine, or twelve months. 

An important factor that makes this problem so persistent and difficult to resolve is the many personas involved. The as-builting workflow is tasked with taking highly technical engineering output from the designers, translating it into instructions that a construction crew can use to safely build the job to code and to standard, then asking a field engineer to draw up the as-builts, and converting those paper drawings into geospatial data that a GIS technician can use to update the utility GIS. Technically this is a complex process that involves distinctly different personas that work in different teams with different technical vocabularies, different training, different software systems, and who are measured by different goals and performance indicators. It is further exacerbated by a lack of clarity as to who owns the as-builting process, engineering, construction, or records/GIS. The designer may point to the contractor as the owner. The contractor might think the GIS technical team is responsible and records/GIS group may think that the designer owns it. Often the real answer is that no one owns as-builting and that is the operative reason the problem has been so persistent for decades.

Digitalizing the as-builting workflow

To improve the efficiency and data quality of the as-builting process digital tools are required to help utilities bridge the gap between the design and the system of record. The key technologies making this possible are mobile applications and mobile devices, cloud technology, and the availability of economical high accuracy GPS. To be successful the tools need to be adapted to the different personas. For the construction crew end user persona a mobile first philosophy is essential to enable real-time data capture in the field. This requires easy to use mobile apps supplemented by high accuracy GNSS and devices such as bar code scanners.  Together these make possible the efficient capture of survey grade data and associated metadata greatly enhancing the speed, accuracy and fidelity of the data feeding the utility systems. In addition a digital data stream makes it possible to update the system of record more rapidly.  This result is the records/GIS to become more effective in producing reliable as-built records that locate and construction crews can rely on.  For utilities that have adopted this approach, enabling field crews to digitally capture construction data is now a best practice.

Example: Digitalizing the mapping of underground duct banks

As a real world example a contractor serving some of the largest utilities in the West Coast of the U.S. was faced with new requirements for the construction project they were working on for a utility customer.  They were now required to capture GPS locations real-time during construction.  Precision was required to be two-tenths of a foot (2.4 inches) or better and location data points were to be collected every 25 feet for linear assets. The contractor had not had to meet requirements like this before on a major project. The scale of this project made the new requirements even more challenging; 35 sites throughout the Central Valley of California, 35,000 feet of trenching, auger bores under highways and railroads, and many primary enclosures.

Fortunately the contractor had had experience with digital construction processes on smaller projects. Based on their previous experience, they were convinced that a member of their own construction crew already on site could capture the location data with the required precision. Having in-house capability for capturing survey grade construction data would allow them to deliver the data without having to have a survey crew on-site or managing outside survey crews. The benefits they hoped to realize were cost savings associated with not having to hire an outside survey crew and related intangibles such as not having to coordinate schedules for survey crews and holding up construction while waiting for survey crews to arrive. However, they were concerned that the the additional training and work load required to capture location data could potentially disrupt their construction crews' schedules.

Key project achievements of digital construction workflow

The implementation of the digital workflow by construction crews actually proceeded rapidly. Crews were capturing survey grade GPS data within days.  Over a period of six months using the solution at 23 active construction sites, over 16,000 feet of buried linear assets, including duct banks and tracer wires, were mapped and some 5,000 supporting photos along the way were captured. The median GPS accuracy of the data captured by their construction crews was 0.14 feet, a remarkable achievement that exceeded the project precision requirement.  Their customer even requested them to go back to pothole and capture accurate locations for trenches that had already been covered over before they began using the new digital process. The many photos that were collected along the way and geotagged to specific locations provided a valuable record of everything that was done in the field for future reference.

Benefits of digital construction workflow

One of the important results of the project was that their initial concern that digital capture in the field by construction crews might disrupt the crews' daily routines never became a problem. Construction crews were able to collect as-built data from open trenches using mobile devices with high accuracy GPS without disrupting their normal processes or impacting their schedules. An important cost benefit was that they didn't have to employ and coordinate survey crews.  Instead of calling in a survey crew they were able to employ one of their own crew members who was already on site to capture survey grade location data. This resulted in an estimated project time savings of around 20%.

An important advantage of the the digital construction process they used enabled them to spot when crew members' shots did not achieve the required project precision. The ability to identify and flag data that exceeded the 0.2 foot accuracy requirement and needed to be repeated was an important factor in achieving the overall project precision goal. Flagging low precision data also avoided the costly process of having to send a vac truck out after the trench was filled to do potholing and retaking shots. Another benefit was automated close out enabling them to receive automated data exports without having to do any paperwork.

The major achievements of digitialization were that survey grade as-builts could be captured in near real time with no disruption to construction crews' schedules, the utility GIS rapidly updated and able to provide up to date, high accuracy underground utility records and all of this at lower cost. Overall the project realized an estimated cost savings of around 50% mainly because fewer man hours were required.

This post is based on Danny Petrecca's talk at the Canadian Underground Forum (CUF). You can listen to all the talks at CUF on the GeoIgnite CUF Youtube channel.

Two states mandate subsurface utility engineering surveys during pre-construction

A major gap in the construction process is the unavailability of reliable information about the location of underground utilities during the design stage of civil engineering construction projects such as highways and pipelines. All states and provinces in North America have one call legislation designed to reduce underground utility damage during actual excavation, but the legislation does not provide for making underground records available to inform the design phase of construction projects. Colorado and Pennsylvania are the first state/provincial jurisdictions in North America to mandate subsurface utility engineering surveys (SUE) during pre-construction.

Making SUE surveys mandatory for certain public construction projects requires changes to the state one call legislation.  For projects for which a SUE survey is required, there is an additional information requirement on network owners and operators.  Before beginning design, the project owner is required to contact the one call centre, who notifies the relevant network operators who then havten days to provide their best available records of the equipment they have in the proposed project area.  On completion of the SUE survey the collected data and report must be provided to an organization which is able to ensure this data store and shared with other construction stakeholders.

Colorado

In 2018 a bipartisan bill to revise Colorado's one call statute was passed in the state legislature. The revised statute (Colorado Revised Statues, Title 9, Article 1.5 Excavation Safety (C.R.S 9-1.5 )) became law in August.  First and foremost among the provisions of the new statute is that it makes subsurface utility engineering (SUE) surveys mandatory on certain public civil engineering projects. There are four criteria for a project to require a SUE survey; it must be a public project, it must be primarily a horizontal project, not a vertical project such as a building, excavation must exceed two feet in depth and the site must encompass a contiguous 1000 square feet, and the project must be designed by a professional engineer. Based on these criteria more than 95% of CDOT projects meet the requirement for a mandatory SUE survey.

The new legislation requires the project owner, CDOT or another agency, to send an information request to the Colorado one call centre for all projects that require a SUE survey. After being notified by the one call center utility owners are required to provide their best available records of their infrastructure in the project area within 10 business days. The project owner is then required to conduct a SUE survey at their own expense and provide the results showing the location of all underground infrastructure and assigned the ASCE 38 quality level to CDOT. Importantly, the SUE document must be stamped (signed) by a PLS or PE to ensure accountability. Standard SUE practice is to achieve at least ASCE Quality Level B for all underground utilities. In the case of conflicts with a new gravity-fed systems it is expected that test holes will be dug to locate and identify conflicts with existing utilities. Furthermore Colorado became an ASCE 38 state and the law requires ASCE 38 to be used on SUE surveys. Currently that means 38-02, but in the future that will become ASCE 38-21 when that version is released.

Pennsylvania

The project owner is responsible for initiating all design projects that will require excavation or demolition. The use of SUE or other similar techniques is required on large or complex projects costing $400,000 or more.

A designer notifies the one call centre by providing the scope of the plan or development with enough detail to allow the facility owners to provide the approximate locations of their lines in the proposed work area. Two types of design notifications are possible.

• Preliminary design: For designers requesting line and facility information more than 90 business days before the final design is to be completed.
• Final design: For designers which are not less that 10, nor more than 90 business days in advance of the final design.

On completion of the SUE survey the project owner is responsible for furnishing the pertinent data obtained through subsurface utility engineering to the One Call system. To assist underground stakeholders with managing their projects and  the associated SUE data, Pennsylvania  811 provides a free web-based application called Coordinate PA (CPA) that provides a repository for underground stakeholders to house and share their project information  and SUE data.  It is designed to help project owners coordinate their projects with other  project owners, designers, excavators, and  facility owners..

PA Act 50 of 2017

The original SUE requirement in Pennsylvania dates from 2006. In 2017 Pennsylvania adopted a new Underground Utility Line Protection Law (PA One Call Law) that requires the following:

It shall be the duty of each project owner who engages in excavation or demolition work to be done within this Commonwealth:

• To utilize sufficient quality levels of subsurface utility engineering or other similar techniques whenever practicable to properly determine the existence and positions of underground facilities when designing known complex projects having an estimated cost of four hundred thousand dollars ($400,000) or more.
• To furnish the pertinent data obtained through subsurface utility engineering to the One Call System in a mutually agreeable format.

Furthermore network owners and operators are required to

• Not more than ten business days after receipt of a request from a designer who identifies the work site of excavation or demolition work for which he is preparing a drawing, to initially respond to his request for information as to the position and type of the facility owner's lines at such work site based on the information currently in the facility owner's possession or to mark the plans which have been provided to it by the designer by field location or by another method agreed to by the designer, excavator and facility owner, or their agent.

The one call system is required to

• Pursuant to policies adopted by the One Call System's board of directors, to provide a secure repository for and access to subsurface utility engineering data received from project owners to affected facility owner members.

Latest statistics reveal reducing damage to underground infrastructure remains a challenge

The ORCGA has just released the 2020 Damage Information Reporting Tool (DIRT) Report.  The report is the result of the efforts made by the ORCGA to collect and compile data about the occurrence of events of underground damage in Ontario. The annual DIRT Report provides a summary and analysis of the known events submitted during the previous year and it also provides the ability to monitor trends over time. The 2020 report focuses on the data gathered throughout Ontario during the three-year period between 2018 and 2020.

In Ontario industry practice is to measure damage prevention performance by the damage ratio metric which represents the number of damage incidents per thousand notifications. Notifications are tickets transmitted from Ontario One Call to underground infrastructure owners in response to a request from an excavator for locating underground facilities. Since 2014 the damage ratio has been gradually increasing. Due to a change in the Ontario One Call process in 2018, notifications in 2019 decreased which affected the damage ratio.

In response to the Ontario One Call process changes, a chart was created to show a new metric, the damage to request ratio, which shows the number of damage incidents per 1000 requests.  A request is a communication from an excavator, typically via Ontario One Call, requesting locate services.  Since 2018 this ratio has slowly decreased, approaching the value it attained in 2014.

Although the volume of damages in Ontario went down in 2020, without some measure of construction activity it is difficult to assign this decrease to a particular cause, for example, reduced construction activity during the pandemic.

Damage statistics (CGA, PHMSA, ORCGA) reveal that underground damage across North America and in the Netherlands (KLIC) plateaued several years ago and may actually be slowly increasing when prorated to construction activity (CGA).  An exception to this trend is the DC DICT system implemented in France where damage statistics reveal a downward trend in the amount of underground utility damage since 2013. Although the number of DTs (requests) submitted is growing every year, the trend in underground utility damage is decreasing, currently by 2 % per year.

France's DT DICT system effective in reducing damage to underground utilities during construction

Since 2013 France has implemented a national damage prevention system that requires achieving 40 cm accuracy for the location of all critical underground network infrastructure prior to beginning construction.  Annual statistics reveal a decreasing trend in the amount of underground utility damage since 2013.

The DT DICT system has some superficial similarities to a North American one call system, but is fundamentally different in that the DT DICT process actually improves the quality of the underground location data as it operates.  The Guichet Unique (Téléservice réseaux et canalisations) contains a list of all utility and telecom operators in France, maps of their services areas, and contact information.  At the beginning of each construction project, the project manager must prepare a DT (Déclaration de projet de Travaux), a notification of planned construction work.  Using the information provided by the Guichet Unique, the DT is forwarded to each network operator with equipment in or near the proposed construction site.

All network operators are obliged to respond to the DT within 9 business days. Operators are required to provide all the information in their possession on the location of their existing networks at the proposed site.  Network operators can respond in two ways. They can provide maps of their underground infrastructure compliant with Class A (accurate to 40 cm). But if they are not able to provide compliant maps, they can request that the project manager carry out one or more investigations complémentaires (IC).  In this case the project manager will contract a locate service provider to conduct locate operations with the objective of ensuring Class A compliance for all noncompliant underground utility facilities. The cost of the investigations complémentaires are borne by the network operator or operators.  The important outcome of this process  is that when the project manager is ready to begin excavation, he/she knows the location of all underground infrastructure at the project site to 40 cm or better. 

The IC process also results in improvements to network operators records, because the regulations require that the results of the investigations complémentaires be sent to the relevant network operators within 15 days.  The network operators are required to update their network records with the information provided in the investigations complémentaires.

Underground damage in France

The DT DICT regulations make reporting incidents of underground damage during construction mandatory for network operators. The National Observatory DT DICT compiles these reports annually and issues a network operator dashboard summarizing the damage statistics for the year.

Year	Damage incidents	Year over year change	Total DTs	Damage rate (% of DTs)	% DTs submitted digitally
2013	24,441		3,437,274	0.71 %	29 %
2014	19,317	-21 %	3,263,725	0.59 %	35 %
2015	18,382	- 5 %	3,349,224	0.55 %	85 %
2016	16,994	- 8 %	3,516,665	0.48 %	89 %
2017	16,698	- 2 %	3,750,933	0.45 %	92 %
2018	16,344	- 2 %	3,966,390	0.41 %	93 %
2019	16,025	- 2 %	4,181,769	0.38 %	93 %

The annual damage statistics reveal that although the number of DTs submitted is growing every year, the trend in underground utility damage is decreasing, currently by 2 % per year.

The decreasing trend in underground utility damage in France is in contrast to North America and the Netherlands where the latest statistics reveal little progress in reducing underground utility damage over the past five years in spite of one call and other measures that have been implemented.

Background

I have blogged previously about the French presidential decree in 2012 that mandated that all of France's critical underground utility infrastructure should be mapped to an accuracy of 40 cm (about 16 inches).  Critical infrastructure according to the decree includes buried electric power cables, pipelines, and public transport infrastructure, but not buried water and telecommunications infrastructure. The deadline for urban areas was January 1, 2019 and for non-urban areas January 1, 2026. 

The national regulation requiring mapping of subsurface infrastructure titled Decree relating to excavations near underground, overhead or underwater transmission or distribution networks was promulgated on 15 February 2012. The "anti-network damage" reform, known as "DT-DICT", came into effect on 1 July 2012. The responsibility for implementing the decree lies with a "competent local authority".  Across France different departmental organizations have taken responsibility for implementing the decree. 

Location accuracy classes

The location accuracy classes apply to planimetry (x, y) and altimetry (z). They are defined as follows: -

Class A: structure for which the maximum location uncertainty is less than or equal to 40 cm if it is rigid or 50 cm if it is flexible; the maximum uncertainty is increased to 80 cm for underground civil engineering structures attached to installations intended for the circulation of rail transport vehicles when these structures were built prior to January 1, 2011;

Class B: structure of which the maximum location uncertainty is greater than class A and less than or equal to 1.5 m; the maximum uncertainty is lowered to 1 m for connections to critical underground structures for safety purposes and from January 1, 2021, for connections to non-critical underground structures.

Class C: structure for which the maximum location uncertainty is greater than 1.5 m, or 1 m for connections to critical underground structures for safety purposes and from January 1, 2021, for connections to non-critical underground structures, or for which the operator is unable to provide accuracy information.

UK's bottom-up/top-down approach to creating a voluntary National Underground Asset Registry

Many jurisidictions are recognizing the human and economic cost of not knowing the location of underground utilities and other infrastructure and are looking at legislative, regulatory, technological, business practice and other measures to find ways to ensure the capture and sharing of reliable underground utility location data. An important question that each jurisdiction needs to decide is whether participation in a scheme for compiling and sharing underground infrastructure data should be voluntary or mandatory. The National Underground Asset Register (NUAR) initiative in the UK has adopted a voluntary approach, most likely because it grew out of a initial grass-roots collaboration of asset owners and the organizations involved in working on maintaining embedded asset networks.

Mandatory or voluntary ?

Colorado

Colorado is among the first state/provincial jurisdiction in North America and in the world to mandate a subsurface utility engineering survey (SUE) at the pre-construction stage. Colorado's legislation provides for strong enforcement options. The new regulations mandates the electronic submission to CDOT of a digital plan, typically the result of a SUE survey, showing all physical offsets, both horizontal and vertical, to all existing utilities, including laterals to buildings, before commencing work on a public construction project. Furthermore, the new regulation requires that accurate as-builts, stamped by a PE or PLS, must be submitted electronically to CDOT within 45 days of the completion of work on a public construction project. 

A technical innovation that the Colorado Department of Transportation (CDOT) has adopted and mandated is a mobile and cloud-based hybrid GIS/surveying system for recording and sharing underground utility location data. CDOT requires its construction contractors to use this app so they are all able to view CDOT data in the field and add to the data as new infrastructure is installed or existing infrastructure is located or relocated in preparation for a road or highway project. CDOT now requires that over 150 utility companies and more than 1,000 utility installation stakeholders to also use this app to capture and record the location of underground utilities.  Furthermore, anyone conducting a SUE survey is required to use this app to record underground utility location and other data collected.

Ontario

In Ontario legislation since 2020 provides strong enforcement options when locates are not completed accurately and in a timely manner. In addition legislation provides strong measures for compelling utilities and other infrastructure owners to improve utility treatments and relocations. But instead of adopting a traditional mechanism involving fines and other penalties for noncompliance based on the legislation, Infrastructure Ontario has implemented a new approach to utility coordination by fostering collaboration among utility owners and government agencies.  Infrastructure Ontario decided to keep the regulatory “big stick” as a rarely used exception and focused on developing a collaborative approach to utility coordination as a more productive and efficient way to achieve better utility coordination. In this vein the Utility Coordination Program (UCP) was launched in March 2020 with the goal of formalizing a new, more streamlined way of performing utility relocation work by enhancing coordination between stakeholders groups. Infrastructure Ontario began working with key utilities and telecoms, the Ministry of Transportation, and the transit agency Metrolinx to develop a program to improve utility coordination. It was recognized that the foundation for a collaborative approach to utility coordination is a single source of project truth. The Office of Utility Coordination (OUC) was setup to became the single custodian of project data and applications.  It was recognized that the foundation for a collaborative approach to utility coordination is a single source of project truth. The Office of Utility Coordination (OUC) was setup to became the single custodian of project data and applications. The primary source of the data is provided by utility and other partners. Metrolinx improves on that data by requring SUE surveys.

Scotland

Scotland has a history of asset owners and roads authorities working collaboratively. For many years this tradition has enabled utilities and telecoms to share details of planned works. In 2012 Scotland implemented a nation-wide collaborative system for sharing information about the location of underground infrastructure among stakeholders involved in road construction including roads authorities, utility and telecom network operators, and Transport Scotland. The Scottish Vault system was implemented by the Scottish road works community on a voluntary basis and remains voluntary. (One of provisions in the recently passed Transport (Scotland) Bill could make the sharing of data mandatory, but it has not been implemented.)

England and Wales

The National Underground Asset Register (NUAR) initiative in England and Wales has also adopted a voluntary approach to bringing utility owners, government agencies and others together in a collaborative environment to share underground utility data. An important reason that participation is voluntary is this initiative grew out of a bottom-up collaboration among actual asset owners and the organizations involved in working on maintaining embedded asset networks in the North East of England and in London. Feedback from the field was that with the practices currently in place data is delivered inconsistently in terms of scale and content making it difficult to integrate and interpret the data in the field. The strong message from the asset owners and those responsible for maintaining the assets was that a simpler, comprehensive, and standardized approach was required. The NUAR project was formally initiated by the Geospatial Commission, which is part of the Cabinet Office at the heart of the UK government. While NUAR is being driven from government, this is very much picking up on a bottom-up requirement.

NUAR background

In 2018 Northumbrian Water brought network operators and local government agencies in Newcastle upon Tyne together at the Northumbrian Water Group Innovation Festival. The event benefited from a spirit of cooperation which enabled 20 utilities, telecoms, local government authorities to voluntarily sit down at the table to collaborate in developing a shared underground infrastructure map showing the location of water, wastewater, gas, electricity, telecoms and other underground services provided by the network owners.

The UK government created the Geospatial Commission to unlock the significant economic opportunities offered by geospatial data.  The NUAR initiative was very much a case of the coincidence of top down interest in digitalization, in general and specifically around geospatial data, and bottom up initiatives by actual asset owners and the organizations involved in working on maintaining embedded asset networks. The Geospatial Commission built on the grass roots initiative in North East England. In addition the Mayor of London’s Office was awarded a share of £3.9m to create a digital map of the utilities and pipes below ground. Known as London's Underground Asset Register (LUAR), the Mayor’s Office worked closely with utilities, transport providers, and six local authorities to create a shared digital map of underground infrastructure. Together in North East England and Central London some 40 utility and telecom network operators and local government agencies voluntarily collaborated to share their data using a harmonized data model and symbology to enable viewing all underground utilities on a single map.

Since completion of the two pilots the Geospatial Commission has announced that it intends to complete procurement for a National Underground Asset Register by Summer 2021. Initially it plans to develop products for three regions, London, Wales, and the North East of England with the intention to complete a national implementation by 2024.

This post is partly based based on the contribution of Neil Brammall, Geospatial Commission, to the panel discussion on the role of government in underground infrastructure at the Canadian Underground Forum (CUF). You can listen to all the talks at CUF on the GeoIgnite CUF Youtube channel.

UK BIM adoption survey reveals facilities/asset management trails other disciplines

The UK Government as part of its building information modeling (BIM) initiative has said repeatedly that it expects the big payoff of a digital model will be during operations and maintenance, which typically represents 80% of the cost of a facility.  But to date there has been limited uptake of a full lifecycle approach focusing on cost reduction during operations and maintenance. Since 2018 there has been begun to be quantitative evidence of the benefits of a full lifecycle integrated BIM+geospatial approach to construction.

The UK BIM Alliance has just released its State of the Nation Survey 2021 to measure the adoption of information management using BIM across the UK built environment. The survey involved 1,170 total respondents with broad cross sector coverage of 25 organizational roles and functions in construction.

Architecture (165 respondents), general contracting(143) and clients/asset owners (115) were the top three best represented organizational roles of respondents.  Of particular note is that nearly 10% of the respondents were clients/asset owners, which have been typically underrepresented in previous BIM surveys.

Main conclusion

The main conclusion about the adoption of BIM in the UK, which has been mandated for public projects since 2016, is that 65% of respondents report that that they have used BIM on projects. Of these organizations most of them have used BIM on at least half their projects. 60% state that they used BIM on over half of their projects.  This equates to 740+ companies that have adopted BIM for at least half of their projects.  It is not clear from the survey whether firms that are working primarily in the private sector are adopting BIM to the same extent as firms working primarily in the public sector where BIM is mandatory.

Awareness and adoption of BIM among disciplines reveals a considerable range. Not unexpectedly the disciplines/functions with the highest BIM adoption rates are architecture (75%), general contracting(76%), and various engineering disciplines (77-89%).

Facilities/asset management is still lagging in BIM adoption

Facilities/asset management (23 respondents) is less well represented in the survey and the BIM awareness and adoption rate for facilities/asset management (43 %) was among the lowest which suggests that the adoption of BIM by the facilities/asset management industry is still very low.  A survey a few years ago of the Facilities Management (FM) industry found that while 92% had heard about BIM and 84% agreed that BIM has the potential to deliver value add to FM, over two thirds said that the FM is not prepared for BIM. The survey suggests that facilities/asset management is still lagging the rest of the industry in adopting BIM and this is inhibiting the broader adoption of a full lifecycle approach to construction.

Accelerating capital investment in new technology for mapping underground infrastructure

The $10 trillion global construction industry is facing a crisis. For many of the world's advanced economies productivity in the construction sector has been stagnant for years.  According to a McKinsey study whereas the average industrial worker adds $37 of value for every hour worked, a construction worker only adds $25. It is estimated that this productivity gap costs the global economy $1.6 trillion every year.

Since the mid 2000s, an increasing proportion of investment in infrastructure has come from private sources; pension funds, insurance companies and sovereign wealth funds which together manage over $60 trillion. According to the World Bank the level of private investment in infrastructure reached about $100 billion by 2015. Private investment expect a financial return and that is driving a growing investment in construction technology to improve productivity.

Historically, investment in research and development by the construction industry has been very low compared to other industries. Several years ago a McKinsey Global Institute study compared the degree of digitalization of nearly 30 industries and concluded that construction ranked at the bottom with hunting.  This is changing. According to McKinsey venture-capital (VC) activity has risen to several billion dollars at the end of 2019 from low levels a decade ago. Specifically VC investment in construction technology far  outpaced the overall VC industry in 2019.

Growing investment in technology for mapping underground utilities

One area that has seen an explosion in the development of new technologies is locating and mapping of underground infrastructure to avoid damage during construction.  It is estimated that not being able to locate information about the location of underground infrastructure cost the US economy tens of billions of dollars every year and is a major risk factor for delays for highway and other linear construction projects.

There are four broad areas of accelerating investment in technology relating to the underground; reality capture, remote detection, mobile + cloud for capturing and sharing location data, and digital twins. Reality capture includes LiDAR and handheld photogrammetry enabling real-time capture of the location of newly installed infrastructure and infrastructure exposed during excavation. Some jurisdictions are using the new reality capture tools to replace traditional paper as-builts with digital point clouds. New detection technology includes inertial or gyro mapping of underground pipe networks, magnetometry using a drone, mapping underground assets using satellite and aerial imagery, quantum effect gravimetry, acoustic locating, advances in ground penetrating radar (GPR) including the ability to capture scans at roadway speeds and software simplifying  the interpretation of GPR scans.  it is estimated that the U.S. spends on the order of $10 billion on locating underground infrastructure prior to and during excavation. Most of this data in not captured and not shared. To address this problem a number of startups have developed mobile  + cloud solutions for capturing underground location data during locate operations, subsurface utility engineering (SUE) surveys, and excavations and sharing this among construction stakeholders. A major area of new technology development is motivated by jurisdictions such as the City of Rotterdam, Estonia and the U.K. that are already developing or plan to develop a digital twin that includes underground and above-ground infrastructure.  This will require large investment in technology to enable real-time monitoring, mapping and data collection, modeling and simulation of entire cities, regions and nations.

Canadian government's approach to managing underground infrastructure on federal land

Public Services and Procurement Canada (PSPC) is responsible for procurement and real property management for federal departments and agencies. There are about a hundred departments and agencies in the Federal government, of which 23 are custodians of real property assets.  PSPC, National Defense and Parks Canada are the largest. PAPC's responsibilities includes underground infrastructure on federal property. PSPC's strategy is a bottom-up approach in which the federal government is working within the framework of existing provincial legislation. In the past two year PSPC has joined all provincial one call centres across the country within that framework is responding to requests for information about underground infrastructure on federal property. PSPC has undertaken the task of creating a PSPC Directive, Standard and Guidelines for the protection of underground infrastructure. Ultimately the intention is to submit these documents to Treasury Board to encourage other agencies that are custodians of real property assets as well as regulatory agencies to adopt a common approach to managing information about underground infrastructure.

In the national capital region PSPC initiated a pilot project with Ontario One Call to see how the one call notification system would work with national and crown owned properties within the National Capital Area (NCA). The first stage of the PSPC requires compiling maps of existing Federal underground infrastructure enabling the government to respond to information requests. To do that required determining what information it intends to share taking into consideration Government of Canada security requirements. Secondly it required that PSPC and other federal agencies register with Ontario One Call. The NCA pilot has made it possible to identify underground infrastructure that would not have been seen without going through the process. As a result PSPC is gaining a better understanding of the relationship with contractors and excavator which is helping build a more robust system and business procedures for collecting location information about underground infrastructure on federal property. The experience that has been gained in the NCA is being passed down to the PSPC regional organizations to enable them to develop similar capacities for managing location data about underground infrastructure.

The challenge is to capture comprehensive data not only about the accurate location of underground infrastructure, but  other properties of the facilities, such as diameter of pipe, cable capacity, type of material, its condition, when it was last inspected, and so on. In each region PSPC is carrying out an inventory of existing underground assets and based on that conducting a gap analysis. The many gaps that were found which were not just missing data, but data that was only available in the form of paper documents. This has motivated a drive within PSPC to get away from paper documents and move to a completely digital environment based on standards that allow this data to be shared easily within the government and with external entities such as utility and telecom operators, contractors and excavators. For example, the Parliamentary Precinct is the responsibility of three or four different government departments each with its own staff. Underground infrastructure on Parliament Hill is already very congested and with the amount of construction and development planned and underway it is essential to know reliably where things are underground and be able to identify clashes with new designs and to be able to hare this data interoperability among the several agencies involved.

PSPC has undertaken the task of creating a PSPC Directive, Standard and Guidelines for the protection of underground infrastructure. This requires engaging with provincial and territorial one call centres, developing the capability to respond to requests for information, and developing business processes to improve the accuracy, timeliness, and comprehensiveness of the data about underground infrastructure that is maintained by the Federal Geomatics group.  The longer term goal is for Treasury Board to encourage custodians of real property asets assets such as National Defense and Parks Canada, as well as regulatory agencies including Transport Canada, Canada Energy Regulator and Innovation, Science and Economic Development (ISED) to adopt similar policies so that this approach to damage prevention becomes pervasive in the Federal government.

Currently this initiative is a bottom-up effort that encourages people to participate voluntarily because of the benefits it provides to them in their work. The goal is develop a concrete, feasible solution that does not disrupt current operations and that will demonstrate the value of the underground information that is being collected and shared with stakeholders. In the future it is expected that the awareness of the significant benefits from better management of underground assets will reach higher levels within government and engender a discussion on ways to collaborate on underground infrastructure throughout the federal government.

Background

In 2015 CSA Z247 the first Damage Prevention Standard in Canada was released. It describes the damage prevention process and elements would reduce damages to Canada's underground infrastructure improving public, worker and community safety and preserving the environment,  It was sponsored by the National Energy Board, Natural Resources Canada, the Canadian Energy Pipeline Association and the Canadian Gas Association. 

In 2014 the Senate Standing Committee on Energy, the Environment, and Natural Resources completed two studies; Moving Energy Safely: A Study of the Safe Transport of Hydrocarbons by Pipelines, Takers and Railcars and Digging Safely - One Call Notification Systems and the Prevention of Damage to Canada's Buried Infrastructure.  The Senate Standing Committee followed this with specific recommendations;

• That the federal government reference the CSA Z247 standard for protection and prevention of damage to buried infrastructure and encourage provinces and territories to reference the standard in legislation.
• That buried facilities on federal land be registered with a provincial or territorial one-call services and that the federal government require anyone undertaking excavation on federal land to call the local one-call centre.
• That the federal government require all owners of federally regulated buried infrastructure to become members of a provincial or territorial one-call service.

This post is partly based based on the contribution of Jennifer Ross, PSPC, to the panel discussion on the role of government in underground infrastructure at the Canadian Underground Forum (CUF). You can listen to all the talks at CUF on the GeoIgnite CUF Youtube channel.

Colorado leads in mandating subsurface utility engineering (SUE) surveys for public civil engineering projects

A major gap in the construction process is the unavailability of reliable information about the location of underground utilities during the design stage of civil engineering construction projects such as highways and pipelines. All states and provinces in North America have one call legislation designed to reduce underground utility damage during actual excavation, but the legislation does not provide for making underground records available to inform the design phase of construction projects. Colorado is the first state/provincial jurisdiction in North America and one of the first in the world to mandate a subsurface utility engineering survey (SUE) at the pre-construction stage. At the Canadian Underground Forum in April, Rob Martindale, Utilities Program Manager at the Colorado Department of Transportation (CDOT) and a Professional Land Surveyor, described the process by which SUE surveys became law in Colorado.

Several jurisdictions around the world have undertaken initiatives to integrate underground infrastructure location data and make it available to all stakeholders. Among the leaders in this effort are the National Underground Asset Registry (NUAR) project in the UK, Singapore's Digital Underground initiative, and the State of Colorado. While the UK and Singapore are in the initial stages of implementation, Colorado has already enacted and implemented legislation and regulations which are transforming underground infrastructure location data for public civil engineering projects across the state.

Mapping underground infrastructure is benefiting from accelerating innovations in technology in detecting, locating, capturing and sharing subsurface utility location data. Experience has shown that enabling these technical advances to permeate and transform business practices in the entire construction industry requires government intervention. The key stakeholders in civil engineering construction are government transportation agencies, utility regulatory agencies, utility and telecom network owners and operators, civil engineering consultants and construction contractors.

Rob Martindale is responsible for improving CDOT's subsurface utility mapping program and utility data management systems. He has been involved from the beginning in the legislative and regulatory processes that are transforming underground infrastructure data in Colorado and is able to provide an insider's perspective on how this process unfolded in Colorado.

As anyone who is involved in civil construction knows, the historical problem with locating underground infrastructure is that utility company records (aka network documentation) are inaccurate, old or outdated, lost, or simply just never existed to begin with. The records that do exist are often inconsistent and the quality of the data is unknown. Records are kept in different data models and formats, typically as CAD drawings, GIS files, paper copies, and PDFs. Some drawings are schematics rather than records of actual utility location. Virtually all of the data is 2D so depth is unknown. Another complicating problem is that in general each utility uses a different base map making it difficult to integrate data from different utilities on a single map. These issues make compiling a reliable map of underground infrastructure in preparation for a civil construction project a challenge. The result is that underground utilities are ignored until excavation begins. As a consequence according to the Federal Highway Administratiion (FHWA) underground utilities are the biggest cause of delays in highway construction projects.

Recognizing the risks associated with underground utilities, CDOT could see that one way to reduce risk was by enabling more reliable and efficient subsurface utility mapping. Since the state is the legal custodian of the public right of way, it had the power to enforce regulations for utility and telecoms with network facilities in the right of way. To CDOT having more reliable location data and more comprehensive attribute data about each utility such as size of pipes and cables and types of material would make for more efficient and productive coordination with utility owners. To achieve this CDOT's vision was a single platform where all underground location and attribute data would be accessible to all stakeholders working in Colorado on current and future civil construction projects.

New legislation revising Colorado's one call statute

In 2015 the Pipeline and Hazardous Materials Safety Administration (PHMSA) conducted an assessment of the Colorado one call system that resulted in a report that identified the lack of an enforcement mechanism as a major impediment to effective prevention of damage to underground infrastructure in the Colorado one call legislation. The PHMSA review had implications in a number of areas including future Federal funding. Then in April 2017, there was a gas explosion in Firestone, Colorado that resulted in fatalities and attracted a high degree of public attention. Recognition that that the incident could have been prevented further prioritized the issue for the Colorado legislature. The result was growing pressure from many construction stakeholders including the Colorado Contractors Association, the American Council of Engineering, American Society of Civil Engineers (ASCE) and CDOT which ultimately attracted the attention of politicians. The initiative was taken up and made a top bipartisan priority by two representatives in the Colorado legislature, Senator Ray Scott, Republican, and Senator Kerry Donovan, Democrat. In 2018 they co-sponsored a bill to revise Colorado's one call statute. The revised statute was signed by the Governor on May 25^th and became law in August, 2018.

The legislation included several important provisions. First and foremost the new law required subsurface utility engineering (SUE) surveys on most public civil engineering projects. It requires the project owner, CDOT or another agency, to notify the Colorado one call center for all projects that require a SUE survey. Furthermore after being notified by the one call center utility owners are required to provide their best available records of their infrastructure in the project area within a 10 business days. The project owner is then required to conduct a SUE survey at their own expense and provide the results showing the location of all underground infrastructure and assigned the ASCE 38 quality level to CDOT. Importantly, the SUE document must be stamped (signed) by a PLS or PE to ensure accountability. Standard SUE practice is to achieve at least ASCE Quality Level B for all underground utilities. In the case of conflicts with a new gravity-fed systems it is expected that test holes will be dug to locate and identify conflicts with existing utilities. Furthermore Colorado became an ASCE 38 state. The law requires ASCE 38 to be used on SUE surveys. Currently that means 38-02, but when the requirement will be ASCE 38-21 when that version is released.

For excavation the Colorado 811 notification process was also modified. It allows the utilities two days to visit the site and mark utilities on the ground before excavation begins.  In addition the new law mandated that all newly installed utilities must be electronically locatable.

Another important provision of the new law was the creation of a one call enforcement mechanism. This was in response to the PHMSA assessment of of Colorado's original one call legislation. The new legislation created an Underground Damage Prevention Safety Commission with the power to levy penalties on utilities that were non-compliant with Colorado's one call requirements. For example, if a utility company fails to provide its best available records within 10 business days, the commission is empowered to levy a fine of up to $75,000.

Integrating SUE into the construction lifecyle

Beginning in August 2018, CDOT adopted a five stage utility project delivery process that includes SUE activities and utility coordination processes.

In the planning stage a design scoping review (DSR) determines whether the project requires a SUE survey. There are four criteria for a project to require a SUE survey; it must be a public project, it must be primarily a horizontal project, not a vertical project such as a building, excavation must exceed two feet in depth and the site must encompass a contiguous 1000 square feet, and the project must be designed by a professional engineer. Based on these criteria more than 95% of CDOT projects meet the requirement for a mandatory SUE survey. In addition at this stage Colorado one call (CO 811) must be notified and utility owners are required to provide their best available records within 10 days. Also in the planning stage a SUE vendor i selected.

In the 0 - 30 % design stage an initial SUE review is conducted to identify all underground infrastructure to ASCE Quality Level D, C, or B. At this stage the SUE survey involves records research, geophysical investigation, professional engineering judgment, knowledge of construction practices and utility design principles all of which are used to determine the quality level to be assigned to each segment of existing utility information.

During the 30 - 90% design stage the goal is to complete the necessary remote detection and test holing to achieve QL B or A for all underground assets at the site. A technical innovation that CDOT has adopted is a mobile and cloud-based hybrid GIS/surveying system for recording underground utility location and other data. The data collected by the SUE vendor is entered into this system which allows the SUE data to be shared among all stakeholders and to be available throughout the entire construction lifecycle.

As an example a project might start with a design in Microstation. The initial SUE data is used to identify potential conflicts each of which is flagged with QL D, C, or B to show the assessed reliability of the location data. Using existing utility data compiled by the initial SUE survey makes it possible to to avoid potential utility conflicts at a very early stage.  This helps avoid costly or time consuming utility relocations. It also makes it possible to identify critical infrastructure and conflicts that may require test holing.  During the 30 - 90% design stage the SUE vendor attempts using remote sensing technology and test holing to achieve QL B or A all underground assets at the site. At this advanced design stage detailed conflicts in 3D can be identified to enable remedial action to be undertaken.  SUE data can be pushed back to the CAD environment for redesign or for utility relocations. SUE data is also made available on CDOT's mobile app for contractors to use in the field to resolve discrepancies in utility surface markings from locating activities resulting from one call notification. The handheld app also makes it possible for contractors to record new test holing that they have conducted and to document utilities exposed during excavation activities.

Colorado has become a model for jurisdictions who have recognized the human and economic cost of inaccurate, out of date and missing data about the location of underground infrastructure. Advances in technology are enabling a revolution in how we detect, capture and share reliable information about the location of underground infrastructure, but, as Colorado is demonstrating, transforming business practices in the construction industry as a whole requires legislation and regulation.

This post is based on Rob Martindale's talk at the Canadian Underground Forum. You can listen to Rob's talk on the GeoIgnite CUF Youtube channel.