SUE: Then and Now

Introduction

Subsurface Utility Engineering (SUE) is an engineering process that has evolved considerably over the past few decades. It has been used primarily by State transportation departments (DOTs), local highway agencies, utility companies, and highway design consultants. The SUE process combines civil engineering, surveying, and geophysics. It utilizes several technologies, including vacuum excavation and surface geophysics. Its use has become a routine requirement on highway projects in many states. It is strongly advocated by the Federal Highway Administration (FHWA) and many other governmental transportation agencies. This paper will explore the evolution of SUE from its conception to what it is today and to what it may become in the future.

SUE Then

SUE began in the early 1980s. Traditional methods of dealing with subsurface utilities were not working. It was common practice back then to design projects without consideration of any utilities and to then deal with them during construction. This resulted in many unnecessary utility relocations, construction delays, and unexpected encounters with subsurface utilities. Associated injuries, deaths, and property damage were commonplace. Necessity being the mother of invention, it seemed possible that two relatively new technologies, nondestructive air/vacuum excavation and surface geophysics, could be combined to gather data on the exact location of subsurface utilities early in the development of projects.

The first users of SUE were state and local highway agencies. These agencies were primarily interested in the safe excavation of test holes. It was widely recognized by highway engineers that it was a good idea to expose subsurface utilities before beginning any excavation. Unfortunately, the only known way to do this was to dig a trench with a backhoe. Far too often utilizing this method, unknown and even known utilities were damaged, resulting not only in damage to the utilities, but often in injuries, deaths, and property damage. Thus, the use of vacuum excavation to expose the utilities was of much interest to many progressive highway people.

The first providers of SUE soon recognized that it was very difficult to find subsurface utilities using vacuum excavation alone. Records provided by utility companies were more often than not inaccurate and incomplete. Hence, the use of emerging surface geophysical equipment was introduced to help determine relatively precise horizontal locations of subsurface utilities. The terms "designating" and "locating" were developed to differentiate surface geophysics and air/vacuum excavation, respectively.

SUE in the beginning was simply locating. It soon grew to be both designating and locating. It then became obvious that other important aspects of SUE were surveying the subsurface information to project control and entering it into clients’ CADD systems or onto project plans. This latter activity became known as data management. Hence by the end of the decade, SUE had grown to be designating, locating, and data management. Other activities associated with SUE by the end of the 1980s included sealing deliverables and obtaining professional liability insurance. These activities led to SUE becoming recognized as a professional service rather than a contractor service.

In the early 1990s the FHWA recognized the value of SUE and began aggressively promoting its use. They did this in many ways, including the following:

• Memos were sent to field offices stressing the benefits of SUE and encouraging Division Administrators and their staff to discuss SUE with State DOT counterparts and to encourage them to give it a try.

• Various forms of literature were developed and distributed to FHWA and State DOT offices (papers, flyers, brochures, handbooks, etc.).

• Numerous papers were written for conferences and publications.

• Funds were obtained for SUE-related research projects.

• Numerous presentations were made at workshops, conferences, meetings, etc.

• Funds were obtained to develop and distribute two videos -- Subsurface Utility Engineering: A Proven Solution and CCC–Making the Effort Works!, and to distribute two videos developed by SUE providers -- Subsurface Utility Engineering - A Technology for the 90's and The Streets of Cheyenne – A Contract Named SUE.

• Workshops were conducted for approximately 20 State DOTs

• Funds were provided for projects to demonstrate the value of SUE in three States ( Oregon, Wyoming, Puerto Rico).

Probably the most significant advancement of SUE in the 1990s involved the introduction and use of the utility quality levels concept. The use of quality levels allows designers to certify on the plans that a certain level of comprehensiveness and accuracy has been provided.

By the mid-1990s, more State DOTs were using SUE and more providers had emerged. But there was much confusion as to just exactly what SUE was. The leading SUE providers were aware that SUE was a process, not just designating and locating, and were promoting it as such. The FHWA also recognized this important distinction and began urging State DOTs to acquire the services of providers that knew what they were doing. It had become apparent to the FHWA and to other proponents of SUE that there was a great need to quantify the value of SUE and to establish standard guidelines for its use. Hence, two things happened:

• It was generally accepted by this time that the proper use of SUE saved time and money but this belief had not been documented. SUE was thus a prime target for the bean-counters. Recognizing the need to provide hard evidence as to its worth, the FHWA commissioned Purdue University to study the value of SUE on highway projects in four States where the SUE process had been used extensively.

• As more and more providers began popping up, it became apparent that some were providing good SUE services but that many were not. To further complicate the situation, many State DOTs didn’t know the difference, and when they obtained a flawed product they immediately concluded that SUE was no better than what they had always done. National guidance was deemed necessary to level the playing field and to set forth the proper use of SUE in a very positive manner. Ultimately, the American Society of Civil Engineers (ASCE) agreed to establish a national standard activity to set forth the responsibilities of engineers, project owners, and contractors for the collection and depiction of existing subsurface utility data on design and construction documents. The FHWA and several SUE providers helped fund this activity.

SUE Now

When the FHWA began promoting SUE in the early 1990s only a few State DOTs were known to be using it ( Virginia, Maryland, Delaware, Pennsylvania, Florida, and Arizona). Today, nearly every State DOT has used it to some extent on highway projects and SUE has expanded into Puerto Rico and Canada. Many state agencies now use the SUE process routinely on every project. In addition, SUE has been used by many local highway agencies, utility companies, and design consultants. SUE has also expanded beyond the highway industry to military, airport, transit, port and other transportation industries.

The growth of SUE has been partially the result of FHWA’s efforts to encourage State DOTs to use it, but most of the credit must go to SUE providers who understood the process and worked tirelessly to sell the concept to potential clients.

The elevation of SUE to a new level is also, in part, the result of the following documents:

• Purdue University’s study, Cost Savings on Highway Projects Utilizing Subsurface Utility Engineering, was published and distributed in 2000. A total of 71 projects from Virginia, North Carolina, Texas, and Ohio had been studied. These projects involved a mix of interstate, arterial, and collector roads in urban, suburban, and rural settings. Two broad categories of savings emerged: quantifiable savings and qualitative savings. A total of $4.62 in avoided costs for every $1.00 spent on SUE was quantified. Qualitative savings were non-measurable, but it was clear to the researchers that those savings were also significant and were possibly many times more valuable than the quantifiable savings. It was concluded that SUE was a viable technologic practice that reduced project costs related to the risks associated with existing subsurface utilities and should be used in a systemic manner.

• ASCE’s standard entitled, Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data was published and distributed in 2003. The intent of this standard was to present a system of classifying the quality of existing subsurface utility data. Such a classification would allow project owners, engineers, and constructors to develop strategies to reduce risks, or at minimum, to allocate risks due to existing subsurface utilities in a defined manner. This document, as a handout or as part of a specification, assists engineers, owners, and contractors in understanding utility quality level classifications and their allocations of risk. The standard closely follows concepts already in place in the SUE profession. Many State DOTs are therefore already in "compliance" with this standard through their use of SUE, or through their inclusion of SUE specifications in their engineering contracts.

The ASCE standard makes it very clear that SUE is a process, not a technology. It defines SUE as a branch of engineering practice that involves managing certain risks associated with:

• Utility Coordination
• Utility Mapping at Appropriate Quality Levels
• Utility Conflict Analysis
• Utility Relocation Design and Coordination
• Utility Condition Assessment
• Communication of Utility Data to Concerned Parties
• And much, much more!

How can all these items be SUE?

Keep in mind that SUE today is a process. It is no longer just paint marks on the ground or vacuum excavation. These technologies are not even mentioned in the ASCE definition. They may be part of SUE, but then again, they may not be. Confused?

Let’s take a look at the use of the SUE process today on a typical project, say a State project that involves upgrading a highway through a small town from 2 to 4 lanes; adding a two-way left turn lane in the median; improving a major intersection with another highway; and providing curb and gutter, sidewalks, and a closed drainage system. A full service SUE provider is employed by the State DOT to handle all utility-related activities. Keep in mind, and this is very important, that the project owner can stop the SUE process at any time. But for purposes of this typical project, we will assume the owner opts for the full SUE process.

Thus, the SUE provider, as a minimum, performs the following tasks:

• Contacts all affected utility companies; sends them preliminary plan sheets and requests as-built information; and investigates other sources of existing utility information. Information obtained is Quality Level D (QL-D) information.

• Makes field observations to obtain visible features information and surveys it to project control. Information obtained is Quality Level C (QL-C) information.

• Compares QL-C & QL-D information and resolves discrepancies.

• Uses appropriate surface geophysical equipment to obtain two-dimensional horizontal information about subsurface utilities; places paint marks on the ground; places identification flags on the paint marks at 50’ intervals; and surveys identified locations to project control. Information obtained is Quality Level B (QL-B) information. May also be requested to also obtain information about aerial utilities.

• Analyzes QL-B information by comparing it QL-C and QL-D information and then with the proposed highway plans.

• Develops a conflict matrix showing all possible highway/utility conflicts.

• Convenes and facilitates a meeting with utility companies to discuss potential conflicts and other aspects of the project. Suggests strategies to avoid conflicts and identifies locations where additional information is needed.

• Uses air/vacuum excavation equipment to expose selected subsurface utilities and obtains horizontal and vertical information at points where additional information is needed. This is Quality Level A (QL-A) information.

• Determines where conflicts cannot be avoided and utilities will have to be relocated.

• Determines prior rights and obtains relocation cost estimates and plans from utility companies.

• Prepares utility relocation agreements.

• Provides utility relocation design and/or works with DOT or consultant designers to be sure they understand the information provided and to suggest possible ways to avoid conflicts.

• Remains available to work with utility companies, one-call centers, and contractors during construction as needed.

• Continues to represent the State DOT in all utility-related activities as the project progresses.

This is not to say that all these activities should be used on every project. Far from it. QL-D information may be all the information deemed necessary for a particular project by design engineers and/or project owners. If not willing to accept that risk, though, they may opt to obtain additional information. Determinations should be made every step of the way until acceptable risk levels are achieved. No matter how many steps are employed, it is all the SUE process.

It should be pretty obvious by now that SUE today is not what it was in 1981, or 1991, or even 2001. It continues to evolve very rapidly. It’s not just a technology anymore. Technologies are just the tools for the SUE engineers to use. SUE today it is an engineering process encompassing every aspect of utility-related work in the most efficient, risk-free, cost-effective manner possible.

SUE Tomorrow

What does the future hold for SUE?

Only a very few people in the early 1980s envisioned what SUE might be today. The growth since then seems phenomenal but may only be the tip of the iceberg.

It seems almost a given that markets in the future will grow exponentially and that technologies will far surpass those in existence today. Today only a small proportion of the existing market has been tapped. Someday the SUE process will be used routinely for highway, transit, airport, port, and all other public and private works transportation projects. It will also be used for buildings, subdivisions, and every other major project where excavation will be required and subsurface utilities may be present. The SUE process will be integral to all construction-related designs. The waste created by unnecessary utility relocations and unnecessarily damaged subsurface utilities will no longer be accepted by project owners, utility companies, or taxpayers/ratepayers.

The SUE process will surely be perfected and expanded to encompass new needs.

Technologies will far surpass those that exist today. Surface geophysics will be perfected to the extent that equipment manufacturers will guarantee horizontal and vertical readings to be accurate within certain minimal tolerances. Vacuum excavation will eventually be almost entirely replaced by surface geophysical technologies. And surface geophysical technologies will also eventually be replaced by technologies or processes that only a few visionaries can see today.

Inventories of utility data will probably be the next big push for progressive highway agencies that have embraced the SUE process. GIS will be incorporated into the process and all SUE information will be so referenced and stored in repositories for future use.

SUE will continue to be an engineering service provided by highly trained and experienced engineers, surveyors, and geologists utilizing the latest technologies.

SUE providers will be held to highest standards of care. They will have to be capable of handling all utility-related matters on public and private works projects from early planning to completion of construction.

The SUE process will live as long as subsurface utilities exist, but not as it is used today. It too will evolve, but only a few today, if any at all, can even begin to imagine how it will be used in the 2010s, the 2020s, and beyond.

Credits
Author(s)
Paul Scott

Publication(s)
Not Published.
Presented at Damage Prevention Conference
December 6, 2005
Dallas, Texas