Excavating mammoth station caverns underground and contending with shallow cover for tunnels in downtown Los Angeles certainly provides engineering challenges to tackle for designers and contractors alike—as they have building the USD 1.7bn Regional Connector transit project.
Speaking with Gary Baker, project director for the Los Angeles Country Metropolitan Transportation Authority, about the Regional Connector he highlights an important trend in construction. “As a project overall, I think the largest challenges were not necessarily related to tunnelling but other areas of the work. We have encountered a lot of unforeseen utilities issues and that has a significant impact on our project.”
Baker says specific to the Regional Connector they were dealing utilities in poor condition. “They had to be reconstructed and rearranged before we could continue with the project, and this happened in two major areas along the alignment. That has resulted in us having to re-sequence the project and mitigate some of those impacts. The contractors worked well finding those mitigations and helped us recover some schedule.” The cause of utilities issues, and therefore cost overruns and delays, can range from unexpected utilities and other problems with site investigations to the bigger picture of the service life, design, installing and rehabilitation of utilities. The only way to correct that is to try to bring more focus to making utility engineering a discipline, says Tom Iseley of the Trenchless Technology Center.
“Research has proven that a major reason for delays or cost overruns in construction has to do with dealing with underground utilities,” says Iseley. “When we really look at life cycle costing of new installation and rehabilitation a lot of it has to do with the design and installation of these systems. But there’s no university that has a civil or construction engineering program that focuses on the utilities.”
This component of the building process, referred to as subsurface utility engineering, is the focus of the American Society of Civil Engineer’s (ASCE) recently established Utility Engineering and Surveying Institute (UESI). UESI formed in October 2015 to offer civil engineering and surveying professionals a recognizable home working in the field, which they can join to collectively work to improve the profession.
“We’re actually moving the design of utilities into a more recognized professional segment of civil engineering,” Iseley explains.
GENERATION SHIFT
UESI president and director of utility marketing and practice development at Cardno, Inc, Jim Anspach attributes issues with utilities to poor records and record keeping, a lack of oversight and ineffective finger pointing among project members.
“No one mandates a particular way to create a record, so the utility owners have a series of very non-standardised ways to go about manufacturing records when they put new infrastructure in the ground,” he says.
The quality of the survey documents to initially to install infrastructure are not needed, nor required, to contain the level of detail that would be necessary for another engineer several years later. Another problem is how these records were made: in the past a record might state, for example, a water main is installed 3ft (1m) inside the edge of a roadway, which could expand or realign over time with no update to the utility’s record.
“One of the reasons we can’t make headway is that there is no one federal or country-oriented agency in charge of all of the underground infrastructure,” he says. In the US water and sewer systems will likely be controlled by individual municipalities or cities; the Federal Communications Commission will control aspects of telecommunications systems, and the U.S. Department of Transport may control aspects of interstate gas pipelines.
“We have this widely divergent regulatory system that creates problems in that these agencies are often competing for money, for power, and don’t necessarily get along with each other, and there is no one over-arching agency that says how we play nice in the sandbox regarding underground utilities placement or development of utility records.”
A lack of ownership among the contractors, engineers, clients and utility owners when something does go wrong further exacerbates the issue.
“One of the things I recognized early on is that probably the right entity to try to take care of that problem is in fact the engineers. The engineer’s mandate is to protect the public’s safety, health and welfare.”
The public is not safe if a utility is struck. The public welfare is not protected from an environmental standpoint or good stewardship of public money if a project has utilities issues, he explains.
“It’s really the engineer’s responsibility to do a study and investigation of existing site conditions more robustly than they do now so they can address these issues. Therefore then the engineers become more of a lightening rod for that single point of accountability.”
For the four parties involved in a project Anspach lays out his argument. The onus is less on the contractors and utility owners—who have no stake in the project in the case of the latter, and may, in some cases, see an opportunity to make money in the former. Meanwhile the client hired the engineer to specifically for this expertise.
“That has been our approach, he says.” We developed some standards first in US, then Australia, the UK, Malaysia, and now in Ecuador, Italy and other places around the world all based on this premise that a good, thorough utility investigation performed by the engineer as part of their design service is the way to go. It’s really started to catch hold, but it really took about 30 years to change the mindsets of people—that in fact it is the engineer’s duty and responsibility to do this.” He says it’s taken a generation to makes this gradual change. And despite the issues that still exist today he sees the light at the end of the tunnel through the development of UESI.
WHERE IT’S WORKING
Broadly speaking there are improvements being made across North America, with some agencies doing particularly well dealing with utility issues—one is the Texas Department of Transportation (TxDot).
“They have been doing a wonderful job of figuring out how to deal with their utility issues in a coordinated way during project development,” says Anspach, explaining the agency has a number of large, high value design-build highway projects. “What they are doing is they are spending money at the 0-10 per cent project development stage, so just after a project gets authorized and notice to proceed, they are able to go out and do a very comprehensive utility investigation and map virtually all the utilities that can be found, with these means of geophysics records and visual inspection, onto the plans before the design even starts.”
The data is given to specialists who understand both design and utility issues. “They kind of straddle the fence between being an advocate for the department of transportation and being an advocate for the utility owner,” he explains. “They look at the plans and they look at what the designers are trying to do, and they give suggestions to the designers on how to avoid having a conflict with a utility.”
This could range from suggesting a different placement, foundation, type of storm drain system, or even moving a structure somewhere else.
“The third rung of that success is that they then take the data at the end during project development, and they keep it fresh. In other words as a utility moves, they change the design plans to show the utility was moved.” He adds, “at the end of the project they actually have a record of where all the utilities are rather than where all the utilities were at the start of the project.”
Another example of successful progress is among transit agencies in Canada building rail systems in cities like Toronto, Ottawa and Montreal. “Those transit agencies are doing a really good job of saying ‘we need to have a 3D model of the existing utilities at the beginning of the project because it helps our designers visualize where they can put things like pedestrian tunnels, and elevator shafts.’”
He adds that the drive to have competent 3D utility maps is really taking hold not only Canada. “It is now filtering over to other countries and it’s very exciting to see.”
MARKET SHIFT
T2 Utility Engineers has worked on infrastructure projects across Canada, from LRT lines to sewer relocations, highways and hospitals, over the last 15 years. Currently, with the recent push for infrastructure development in Canada, the firm is seeing a lot of work for LRT projects. One in particular is Toronto’s Finch West LRT.
“It’s one where we followed the ASCE 38-02 standard during the utility mapping component,” Lawrence Arcand, T2 president explains. “We also followed very good principles associated with utility coordination, by allowing us to clearly identify those utilities that would be impacted by the project, and allowed us to give the proponents good information so that they could prepare their bids.
“What we were also allowed to do was identify upfront some of the critical utility components that could cause schedule and cost impacts—those high risk components—and we were able to do advanced utility relocations to get those utilities out of the way and make it a much cleaner package for the bidders.” One significant high risk component on the Finch West project was a 30-inch, extra high pressure gas main, running down the middle of Finch Avenue through a large portion of the project limits.
“We were able to clearly identify the exact location of that gas main using our subsurface utility engineering process and then once we identified it we were able to adjust the alignment of the new LRT to minimize the impact on that gas main. And those areas where we were not able to eliminate the impacts we were able to do a lot of that work as advanced relocations, so that it will be removed by the time the proponents will come on board to build the project.”
Arcand, says he started doing subsurface utility engineering around 15 years ago, “spreading the word, making the Canadian marketplace aware the service existed and how it can be of assistance on projects. It’s been a long, uphill climb, in terms of getting buy in from the market, and getting people on board.” Now in key markets like Alberta and the Toronto area it’s becoming a well recognized, common service line to utilise on capital infrastructure projects. “It’s almost become mainstream,” he reports. “There’s still a ways to go, but we’ve made a lot of strides.”
In addition to T2, which he says has grown significantly, there have been other providers that have come on board bringing some legitimacy to the market by having multiple providers that clients can go to and to perform the work.
Arcand and his colleagues have gotten involved with subcommittees of the Transportation Association of Canada and the Ontario Public Works Association. They’ve also worked with the Canadian Society of Civil Engineering and the Centre for Advancement of Trenchless Technologies.
“We were able to get subsurface utility engineering written into some of the national standards so that people were aware of it,” he says, adding, “by taking that lead role in some of those key organizations, as well as maintaining a very high level of standards in terms how we produce deliverables and making sure that service resides within the realm of a professional engineering discipline. It’s really elevated the service and allowed it to grow and become common place.”
While there has been a lot of uptake on utilizing the services, it’s still not done on every single project, and it’s still not fully understood, Arcand reports. “I like to say it’s ether in its infancy or toddler ages, and still has a lot of growing up and maturing so that it does become just common place on all projects.” In his view there needs to be more consistency among providers, to ensure services are being done properly and following the ASCE 38-02 standard.
TECHNOLOGY SHIFT
There are improvements to anticipate in particular with the techniques used to identify the utilities, such as multi channel ground penetrating radar (GPR), and the way data is actually being portrayed on drawings, moving more to 3D models.
“I’m always of the opinion that in a perfect world eventually as a SUE provider we’d work ourselves out of business,” Arcand says. “It’s really a shame that we do have such poor records of our underground utility infrastructure.
“What we need to be doing is drawing line in the sand and essentially, going forward, create much more reliable, accurate records of where we put utilities in the ground, and merge that data into what comes out of SUE investigations of existing utilities.
“Maintain that data in some repository, whether that’s held by the right of way owner, or the utility owner or some third party, and have a much better centralized system for keeping that data on an on-going basis so we don’t have to go out and map it every single time and we do have an accurate depiction of what’s actually out there underground.”
He admits that’s a huge undertaking, and like most people Tunnels & Tunnelling North America spoke to for this article that there’s no obvious answer how to tackle it. He says, “it’s got to be something where we draw a line and start the process. Eventually 20, 30, 40 years we’ll have system in place that works.” Ron LaBarca, president of US Radar, is one of the many in agreement. Based in New Jersey, US Radar is a GPR and subsurface imaging systems manufacturer. He says, “Often times owners are not able to transmit information about their infrastructure and at other times are reluctant to do so. When all interested parties make every effort to find, identify and preserve locations for future use, projects go much smoother. Compiling accurate maps—maintained by the utility or property owner and freely shared and amended for all to use—is the biggest improvement that can happen.”
Recent innovations have enabled users of GPR to instantly create point files of their findings using on-board GPS and then export those point files into any drawing or mapping program to create a usable deliverable, LaBarca explains. “Advances in processing have enabled us to offer multiple frequency/ bandwidth, amazing processing algorithms, and automatic antenna configuration/calibration, to name just a few.” Earlier this year US Radar launched its latest product, the GP Rover. Field data collected by the GP Rover may be saved and shared in five of the most common file formats used in popular mapping and engineering applications such as AutoCad, Google Earth, GIS and point files.
Troy De Souza, training manager with Ontario’s Sensors & Software Inc, says it important people understand the role GPR can play in subsurface utility engineering.
“This technology is viable, it’s easy to use, and it compliments existing pipe and cable locators. The other key thing is to know the capabilities of what they can do after they collect data.
“You can integrate this with other data, into AutoCad drawings export into Google Earth, do reports as easy-to-read maps.”
Speaking with Jennifer Lighthall and Robert Parrillo of GSSI, manufacturer of utility scan systems, they point out, the hardware and the software will continue to evolve, making it easier and smarter, more automatic, and easier to create a permanent record.
STANDARDIZATION
GPR is one necessary item in the SUE tool box, however industry advocates reiterate any technological advancements and potential can only best be utilized with improved coordination and standardization.
UESI’s Anspach describes a bell-shaped curve of diligence and ways of delivering utility information. At one end is a utility owner marking the ground for a surveyor to survey the area before putting utilities on the plans for the contractor. That’s not a professional service, he says.
“On the other end of the spectrum you have a few companies that have the whole company trained in utility engineering and surveying issues, and you have a host of professionals that understand geo physics, survey and positioning, data management, design of projects and how they all integrate, and quite frankly there are probably only five to six, a handful, in the world that are at that end of the spectrum.
“That’s where we would like more companies to be and we’re moving that way,” he says. “But then you have this whole middle area where you have firms that think they have the expertise because they have a license to practice engineering for surveying and they really don’t have as much expertise as they should to be practising in this business.”
That’s one of the prime areas that the ASCE is trying to tackle, which is to raise the bar of practice. The goals include certifying not only the reports and deliverables, but also the individuals who collected the data: certifying the utility engineers and their understanding of geo physic theory, utility configuration and data management, as well as CAD operators, Anspach explains.
Individuals can obtain certification at the Louisiana Tech’s Trenchless Technology Center where Iseley has started a five-day short course called the Utility Investigation School, in conjunction with UESI, to provide practitioners with the knowledge and tools to provide competent utility investigations in accordance with national standards (ASCE 38-02), and to defend against claims through this knowledge and its documentation.
Anspach explains, “What we’re trying to say is that if you use standard ASCE 38 that means that you have to put your professional seal on the plans that says ‘I’m responsible for negligent errors or emissions in prosecuting this work.’
“And everybody then realizes that if somebody is using that standard and certifying that they used that standard, then that will in fact give some level of assurance to the users of it that there were good practices used in developing not only the deliverables in also performing the utility investigation.”
