**PURDUE UNIVERSITY STUDY**

**COST SAVINGS ON HIGHWAY PROJECTS**\
**UTILIZING**\
**SUBSURFACE UTILITY ENGINEERING**

Prepared by\
Purdue University\
Department of Building Construction Management

December 1999

Prepared for the\
Federal Highway Administration\
Washington, DC

FHWA Contract Number DTFH61-96-00090

**TABLE OF CONTENTS**

[ABSTRACT](#ABSTRACT)

[EXECUTIVE SUMMARY](#EXECUTIVE)

[REPORT](#report)\
[Scope of Study](#scope)\
[Overview](#overview)\
[Benefits](#benefits)\
[Types of Costs](#types)\
[Evaluation Plan](#evaluation)\
[Results](#results)\
[Conclusions](#conclusions)\
[Recommendations](#recommendations)\
[More Information](#more)

COSTS SAVINGS SUMMARY SPREAD SHEET (Not Included)

APPENDIX I. VIRGINIA DOT DATA (Not Included)

APPENDIX II. NORTH CAROLINA DOT DATA (Not Included)

APPENDIX III. OHIO DOT DATA (Not Included)

APPENDIX IV. TEXAS DOT DATA (Not Included)

APPENDIX V. DEMONSTRATION PROJECTS (Not Included)

[]{#ABSTRACT .anchor}**ABSTRACT**

The Federal Highway Administration (FHWA) has been promoting the use of
subsurface utility engineering (SUE) since 1987 as a means to save costs
on highway construction projects. In 1996, the FHWA commissioned Purdue
University to study the cost savings from four states\' dots that
routinely utilize utility quality levels while producing contract
drawings.

A total of seventy-one projects (71) from Virginia, North Carolina,
Texas, and Ohio were studied. The total construction costs of these
projects were in excess of one billion dollars. These projects involved
a mix of Interstate, Arterial, and Collector Roads in urban, suburban,
and rural settings. DOT project managers, utility owners, constructors,
and designers were interviewed. Two broad category of savings emerged:
quantifiable savings and qualitative savings.

A total of \$4.62 in savings for every \$1.00 spent on SUE was
quantified. Qualitative savings were non-measurable, but it is clear
that those savings are also significant and may be many times more
valuable than the quantifiable savings. Only three projects returned
less in savings than expenditures. This leads to the conclusion that SUE
is a viable technologic practice that reduces project costs related to
the risks associated with existing subsurface utilities and should be
used in a systemic manner.

Keywords: subsurface utility engineering, utility mapping, utility
quality levels, Purdue University, construction risk management, value
engineering, SUE

[]{#EXECUTIVE .anchor}**EXECUTIVE SUMMARY**

The Federal Highway Administration (FHWA) commissioned Purdue University
to study the effectiveness of subsurface utility engineering (SUE) as a
means of reducing costs and delays on highway projects. The
effectiveness study was conducted and the results and accompanying
recommendations are presented here. The concepts and practice of SUE
have been developed and refined over many years, but basically were
systematically put into professional practice in the 1980s. Several
states have programs whereby the state Department of Transportation
(DOT) contracts with SUE providers to map utilities on their projects.

Subsurface utility engineering is the convergence of new site
characterization and data processing technologies that allows for the
cost-effective collection, depiction, and management of existing utility
information. These technologies encompass surface geophysics, surveying
techniques, mapping techniques, CADD/GIS systems, *etc*. Rather than
disclaiming responsibility for existing utility information, subsurface
utility engineers certify utility information in accordance with a
standard classification scheme (utility quality levels) that allows for
a clearer allocation of risk between the project owner, project
engineer, utility owner, and constructor

Previous studies and statements of cost savings were performed by
various state DOTs, providers of SUE services, and the FHWA.
Commissioning Purdue University to conduct this study allowed for an
independent and impartial review and study of costs savings.

Virginia, North Carolina, and Ohio were initially selected to be part of
this study. Texas was added due to their rapidly growing SUE program.
These four states had a total of 71 projects studied in detail. These
projects were selected randomly from a list of projects that utilized
SUE. They involved a mixture of Interstate, arterial, and collector
roads in urban, suburban, and rural settings. DOT project managers and
engineers, utility owners, constructors, designers, and subsurface
utility engineers were interviewed.

Wyoming, Puerto Rico, and Oregon were given *seed* money from the FHWA
to try SUE on a select project. These projects are also included in the
study (see Appendices), although data from these projects are extremely
limited. Finally, several other states have studied their own projects
or programs and have supplied information for this study. Overall,
approximately one hundred projects were evaluated in some level of
detail in order to accomplish the FHWA study mission.

A savings of \$4.62 for every \$1.00 spent on SUE was quantified from a
total of 71 projects. These projects had a combined construction value
in excess of \$1 billion. The costs of obtaining Quality Level \"B\" (QL
B) and Quality Level \"A\" (QL A) data on these 71 projects were less
than 0.5 percent of the total construction costs, and it resulted in a
construction savings of 1.9 percent over traditional Quality Level C (QL
C) and/or Quality Level D (QL D) data. Qualitative savings were
non-measurable, but it is clear that those savings are also significant
and may be many times more valuable than the quantifiable savings.

The figure \$4.62 is somewhat less than the \$7.00 to \$1.00 (Previous
Virginia DOT study), \$18.00 to \$1.00 (previous Maryland DOT study),
and \$10.00 to \$1.00 (Society of American Value Engineers) returns on
investment that were previously reported in the literature. However, the
quantity of studied projects is much higher; the projects are more
random in nature; and no qualitative costs were included in the total.
Indeed, one individual project had a \$206.00 to \$1.00 return on
investment (North Carolina DOT). Only 3 of 71 projects had a negative
return on investment.

The simple conclusion of this study is that SUE is a viable technologic
practice that reduces project costs related to the risks associated with
existing subsurface utilities and, when used in a systemic manner, will
result in significant quantifiable and qualitative benefits. Using the
SUE savings factor data from this study and a national expenditure in
1998 of \$51 billion for highway construction that was provided by the
FHWA, the use of SUE in a systemic manner should result in a minimum
national savings of approximately \$1 billion per year.

[]{#report .anchor}**REPORT**

[]{#scope .anchor}**Scope of Study**

The Federal Highway Administration (FHWA) commissioned Purdue University
to study the effectiveness of subsurface utility engineering (SUE) as a
means of reducing costs and delays on highway projects. The
effectiveness study was conducted and the results and accompanying
recommendations are presented here. The concepts and practice of SUE
have been developed and refined over many years, but basically were
systematically put into professional practice in the 1980s. Several
states have programs whereby the state Department of Transportation
(DOT) contracts with SUE providers to map utilities on their projects.

Previous studies and statements of cost savings were performed by
various state DOTs, providers of SUE services, and the FHWA.
Commissioning Purdue University to conduct this study allowed for an
independent and impartial review and study of costs savings.

Virginia, North Carolina, and Ohio were initially selected to be part of
this study. Texas was added due to their rapidly growing SUE program.
These four states had a total of 71 projects studied in detail. These
projects were selected randomly from a list of projects that utilized
SUE. They involved a mixture of Interstate, arterial, and collector
roads in urban, suburban, and rural settings. DOT project managers and
engineers, utility owners, constructors, designers, and subsurface
utility engineers were interviewed.

Wyoming, Puerto Rico, and Oregon were given *seed* money from the FHWA
to try SUE on a select project. These projects are also included in the
study (see Appendices), although data from these projects are extremely
limited. Finally, several other states have studied their own projects
or programs and have supplied information for this study. Overall,
approximately one hundred projects were evaluated in some level of
detail in order to accomplish the FHWA study mission

[]{#overview .anchor}**Overview**

Many design and construction projects are taking place in areas where an
abundance of underground utilities already exists such as in cities,
process plants, airports, highways, and so forth. These existing
utilities create risks for the project owner, designer, and constructor.
Although there are many reasons for these risks, one of the fundamental
reasons is that accurate data on the location, and even sometimes on the
existence of these *out-of-sight* utilities, are rare. Existing records
of underground site conditions are usually incorrect, incomplete, or
otherwise inadequate because:

-   They were not accurate in the first place: design drawings are not
    *as-built*, or installations were *field run* and no record was ever
    made of actual locations;

-   On old sites, there have usually been several utility owners,
    architects/engineers, and contractors installing facilities and
    burying objects for decades in the area. Seldom are the records
    placed in a single file, and often they are lost. There is almost
    never a composite;

-   References are frequently lost: records show that an object is a
    certain distance from a building that is no longer there, or an
    object is a certain distance from the edge of a two-lane road that
    is now four lanes or is part of a parking lot;

-   Lines, pipes, and tanks are removed from the ground, but aren\'t
    removed from the drawings.

Engineers recognize this problem of records with incorrect or incomplete
information, and attempt to protect themselves through prominently
displayed notes on the drawings. Although these notes may vary in
wording, a typical example is as follows:

> *Utilities depicted on these plans are from utility owner\'s records.
> The actual locations of utilities may be different. Utilities may
> exist that are not shown on these plans. It is the responsibility of
> the contractor at time of construction to identify, verify, and safely
> expose the utilities on this project.*

Contractors may employ multiple mechanisms to protect themselves.
Certainly, the types of excavation equipment used can be important. All
states now have a *one-call* statute in place whereby the contractor
must call all known utility owners before construction begins. Utility
owners then have the burden of marking their utilities on the ground
surface for damage prevention purposes. Many times, the *paint* marks
indicating the location of the utilities do not agree with the utilities
depicted on the design plans. Contractors know this will happen and
typically increase their bid price to account for this contingency. They
will also ask for change orders and claims when necessary. Usually the
project owner is obligated to pay these change orders and claims due to
utilities being treated as a *differing or unknown site condition* in
the standard contract documents. Some states allow the contractor to
seek relief from the designer even though there is no contract between
the contractor and the engineer.

Project owners rarely end up with any protection for unknown,
unrecorded, or mis-recorded utility data. Savvy project owners are
beginning to realize this fact. They are either requiring their
engineers to take some responsibility for more accurate utility
information or they are hiring specialty engineering firms to obtain
more accurate information.

A convergence of new site characterization and data processing
technologies now allows for the cost-effective collection and depiction
of existing utility information. These technologies encompass surface
geophysics, surveying techniques, CADD/GIS systems, etc. This
convergence is now known as subsurface utility engineering. Rather than
disclaiming responsibility, subsurface utility engineers collect utility
data and certify its quality. The accepted definition of subsurface
utility engineering is:

> *A practice of engineering that manages the risks associated with
> subsurface utilities via: utility mapping at appropriate quality
> levels, utility coordination, utility relocation design and
> coordination, utility condition assessment, communication of utility
> data to concerned parties, utility relocation cost estimates,
> implementation of utility accommodation policies, and utility design.*

In order to understand SUE, it is important to first define the quality
levels of utility information that are available to the design engineer,
constructor, and project owner. The concept of quality levels was
developed from the realization that sometimes more reliable information
on the location of underground utilities is known to the engineer, but
is not typically presented within any documents for the benefit of
others. Examples of the wide range of notations made include a gas line
for which there exists a certified reference to recoverable survey
control portrayed in the same manner as a water line for which there is
only a verbal recollection by a water company representative.

Four separate quality levels of utility information are now generally
recognized by various organizations. The Federal Highway Administration
has taken the lead in promoting and using this concept. Other
organizations such as the American Society of Civil Engineers (ASCE),
Federal Aviation Agency (FAA), Network Reliability Council, various
state DOTs, county governments, and so forth have also used this
concept.

The generally accepted definitions are as follows.

-   Quality Level D (QL D): Information derived solely from existing
    records or verbal recollections.

-   Quality Level C (QL C): Information obtained by surveying and
    plotting visible above-ground utility features and by using
    professional judgment in correlating this information to Quality
    Level D information.

-   Quality Level B (QL B): Information obtained through the application
    of appropriate surface geophysical methods to identify the existence
    and approximate horizontal position of subsurface utilities.
    \"Quality level B\" data are reproducible by surface geophysics at
    any point of their depiction. This information is surveyed to
    applicable tolerances and reduced onto plan documents.

-   Quality Level A (QL A): Information obtained by the actual exposure
    (or verification of previously exposed and surveyed utilities) of
    subsurface utilities, using (typically) minimally intrusive
    excavation equipment to determine their precise horizontal and
    vertical positions, as well as their other utility attributes. This
    information is surveyed and reduced onto plan documents. Accuracy is
    typically set at 15mm vertical, and to applicable horizontal survey
    and mapping standards.

Determining which quality level must be met is an important
responsibility of the project owner. In other words, if the owner
specifies lower-quality information to the design engineer, the owner
must be willing to pay for the associated costs in project delays, bid
contingencies, change orders, unnecessary utility relocations, redesign,
and perhaps utility damage and other problems. Most projects currently
proceed by owner specification at Quality Level C whether or not the
owner realizes it. However, engineers should encourage owners to specify
higher levels, and inform owners that they may incur liability for
lower-quality level depictions.

On projects where owners specify a desire for the highest-quality level
of utility information, decisions and judgments must be made by the
parties as to costs versus anticipated results. These decisions and
judgments will require a thorough knowledge of existing surface
geophysical techniques, their costs, and their limitations. Engineers
will recommend and apply appropriate techniques based upon owner budgets
and expectations. Decisions and judgments must also be made as to where
Quality Level A data should be provided. Finished plans may contain
utility data with different quality attributes\--all four quality levels
may be represented.

[]{#benefits .anchor}**Benefits**

There are numerous benefits obtained when using SUE on highway projects.
By using SUE, significant benefits are derived for the DOT, utility
companies, SUE consultants, contractors, and the general public. Some of
the benefits that have been obtained are as follows:

-   Reduction in unforeseen utility conflicts and relocations;

-   Reduction in project delays due to utility relocates;

-   Reduction in claims and change orders;

-   Reduction in delays due to utility cuts;

-   Reduction in project contingency fees;

-   Lower project bids;

-   Reduction in costs caused by conflict redesign;

-   Reduction in the cost of project design;

-   Reduction in travel delays during construction to the motoring
    public;

-   Improvement in contractor productivity and quality;

-   Reduction in utility companies\' cost to repair damaged facilities;

-   Minimization of utility customers\' loss of service;

-   Minimization of damage to existing pavements;

-   Minimization of traffic disruption, increasing DOT public
    credibility;

-   Improvement in working relationships between DOT and utilities;

-   Increased efficiency of surveying activities by elimination of
    duplicate surveys;

-   Facilitation of electronic mapping accuracy;

-   Minimization of the chance of environmental damage;

-   Inducement of savings in risk management and insurance;

-   Introduction of the concept of a comprehensive SUE process;

-   Reduction in Right-of-Way acquisition costs.

[]{#types .anchor}**Types of Costs**

The reductions in risk for projects utilizing SUE have been difficult to
quantify. There are many variables and scenarios that may occur.
Historical data is difficult to come by. Some savings are easily
quantified; others may be qualitative or speculative in nature. This
study categorizes savings accordingly. These types of costs are:

-   Exact costs that can be quantified in a precise manner. Examples are
    costs much like the costs for test holes, the cost to eliminate
    construction and utility conflicts, or any other cost for which
    exact figures can be obtained.

-   Estimated costs that are difficult to quantify, but can be
    calculated with a high degree of certainty. These costs were
    estimated by studying projects in detail, interviewing the personnel
    involved in the project, and applying historical cost data.

-   Costs that cannot be estimated with any degree of certainty due to a
    lack of data. These are true qualitative costs and may in fact be
    significant to the real cost savings. These qualitative costs are
    not quantified in the evaluation study.

[]{#evaluation .anchor}**Evaluation Plan**

Three primary methods were used to examine, study, and collect data on
the application of SUE.

-   Conduct an analysis of the overall program of SUE within each study
    state. This approach involved a cursory examination of all projects
    utilizing SUE within a particular state.

-   Select and study individual projects. These projects were selected
    with input from appropriate Departments of Transportation to obtain,
    as best possible, a mix of projects ranging from simple to complex.
    One of the selection criteria was to select projects that the
    designers, constructors, and users were still available to contact
    and interview.

-   Use a modified combination of the above approaches to analyze SUE.
    Application of this approach depends on the states being studied.
    The methods used were specific project analysis where available, and
    program analysis for overall conclusions.

Some of the items investigated during the interviews and analysis were
old utility records and locations (Quality Level D and C information).
They were compared to the new upgraded locations (Quality Level B and A
information), and the differences were compared to determine the
benefits of SUE. The guiding concept utilized with this approach was to
obtain data and information on SUE activities from the people who
actually were involved in the project.

In addition to conducting interviews and reviewing the available and
utilized quality levels and their project impacts, the available paper
trail was also investigated. For example, similar projects that used and
did not use SUE were examined for existence and quantities of change
orders, extra work orders, delay and other claims, time extensions, etc.
State and Federal tracking forms for allocation of costs for utility
relocations, prior rights, and correspondence were valuable to the
study.

[]{#results .anchor}**Results**

[Virginia]{.underline}

The Virginia Department of Transportation estimates an annual
expenditure of approximately \$10 million on SUE in a variety of
contracting methods. Virginia has three SUE firms under contract to
provide utility mapping (all quality levels) in nine separate districts.
Additionally, the DOT\'s statewide and regional survey contracts require
QL B mapping for select projects. There are two regional consultants
providing utility coordination services. There are four regional
consultants providing utility relocation design. Certain large projects
have subsurface utility engineering (utility mapping, utility
coordination, and relocation design) built in to the project
requirements. All highway projects in Virginia are required to use SUE,
and most projects utilize Quality Levels A and B information. SUE
information has also proven useful to utility companies in their
relocation design.

Virginia started their program in 1984. Virginia has the most
comprehensive program in the nation. They utilize every aspect of SUE
with a combination of in-house and consultant forces. They estimate a
project delivery time savings of 12 percent-15 percent has resulted from
their systemic approach to utility risk management. Utility owners have
been more cooperative after the DOT SUE program commenced. Quality level
B mapping identifies an average of 10 percent - 50 percent more
utilities than traditional mapping (QL D and QL C).

[North Carolina]{.underline}

The North Carolina Department of Transportation (NCDOT) began a
subsurface utility engineering program in 1991, after studying the
successes of Virginia, Delaware, and Pennsylvania\'s programs. SUE began
as a trial program by NCDOT and has gradually evolved into a continuous
process. The primary reason for utilizing SUE in North Carolina is to
reduce the cost of highway construction. Cost reduction can be obtained
through the elimination or reduction of claims, change orders, and
construction delays, and through the minimization of disruption to
utility services.

SUE began as an aid to in-house-designed projects with an initial
contract with one provider valued at approximately \$300,000. The
program was successful and, as a result, additional SUE consultants were
brought under contract. Currently there are four providers; however, the
contract values are not equal. For designs performed by outside
consultants, i.e., non-state employees, the DOT requires that the
outside designers hire one of the four state-DOT-approved SUE
consultants for their team. Consequently, the two contracting methods,
i.e., state contract for in-house design and project contract for
outside-consultant design, result in a total, state, DOT SUE program
valued at approximately \$3,000,000 per year. This represents a SUE
budget of approximately 2 percent of the total state engineering/
construction budget.

When SUE was initially utilized in North Carolina, a formal review
procedure was adopted that was used for one or two periods. The use of
the procedure was informally abandoned for no given specific reason. SUE
is now employed in North Carolina by an informal procedure based on
cooperation between design engineers and area engineers. This informal
procedure is accomplished by mutual agreement and judgment between
design and area engineers on an as needed project basis due to amount of
utilities, potential impact, and engineering judgment. Now that many of
the design and area engineers have become familiar with the concepts of
SUE, the informal process is working well.

NCDOT only utilizes the utility mapping components of SUE. So far, the
NCDOT handles utility coordination and utility relocation design with
in-house forces. There has been some discussion to attempt a trial
project where all aspects of SUE are performed by a SUE consultant. This
would include utility mapping, utility coordination (with utility
owners), and perhaps some utility relocation design for publicly owned
utilities.

The evaluation study has computed a cost savings of \$6.63 for every
dollar spent for SUE in North Carolina. The total amount of expenditures
to date for SUE in North Carolina is \$8,725,371.97. This represents a
projected savings of \$57,849,211.39 since the SUE process was started
in North Carolina. The SUE savings computed in this study are related to
the in-house projects designed and constructed by the NCDOT.

NCDOT appears to have figured out how to use SUE effectively in their
state and are doing so for the benefit of the taxpayer and ratepayer.
NCDOT has utilized SUE for eight years, with a progressive amount of
contract value. They are currently funding SUE at levels in excess of
\$3 million per year. It is difficult to estimate non-quantifiable
savings resulting from decreased utility damages, bid prices,
construction delays, and so forth; however, quantifiable savings (after
studying about 7 percent of NCDOT\'s in-house projects on both a cost
and project basis, indicating a return in excess of \$6.60 for every
dollar spent) were obtained. Therefore, a quantifiable savings per year
for NCDOT projects is approximately \$19.8 million. The majority of
projects utilizing SUE showed no delays due to utility conflicts, an
improvement over past engineering practices.

[Ohio]{.underline}

The development of Subsurface Utility Engineering (SUE) in Ohio was
started in 1992 with a trial project in the city of Columbus. In May
1995, after evaluation of that project\'s success, the FHWA funded SUE
through a demonstration-projects mechanism for the Ohio Department of
Transportation (ODOT).

The primary reason for utilizing SUE in Ohio is to reduce the cost of
highway construction. Cost reduction is obtained through the elimination
or reduction of claims, change orders, and construction delays, and
through the minimization of disruption of utility services. SUE was
initially used to solve field utility conflict questions; subsequently
it has evolved into some design processes.

Ten of the twelve Districts in Ohio have used SUE on at least one
project. Due to successes in the urban districts of Cleveland and
Akron/Canton, these two Ohio districts have their own SUE contracts,
while the other ten districts share a statewide contract. In Cleveland
and Akron/Canton Districts, the Production Department (essentially
design and construction) selects projects for SUE. This has evolved
today to include virtually every project. In the other districts
employing SUE, the District Utility Coordinator selects projects for the
use of SUE with input from construction departments. The District
Utility Coordinator informs the Central Office who administers the SUE
contract and assigns a SUE provider to the District\'s project on an
alternating basis. The provider then sends the district an estimate for
SUE services, based on the scope specified by the District Utility
Coordinator. The Central Office then formally assigns the project to the
SUE provider.

One advantage of this system is that the districts do not have to
allocate funds for SUE before the use of SUE. The Central Office
supplies the funds, and then back-charges the districts only for those
actual SUE expenditures. When using Central Office Funds, the districts
do not need to be concerned about losing funds if they are not used. The
disadvantages of this system include less local control of SUE services,
no choice in SUE providers, and (typically) a less timely procurement of
SUE services in the design phase of projects.

Overall, the savings analysis for Ohio was determined to be \$5.21 for
every dollar expended for SUE. The fourteen projects included in this
Ohio SUE evaluation total \$284,349,202.07 in construction costs. The
net SUE savings (SUE savings less the cost of SUE) is \$3,418,069.47.

Applying the ratio of net SUE savings to the construction cost of the
SUE evaluation projects yields an annual projects savings of
\$12,080,000 based on the total highway construction amount.

[Texas]{.underline}

In 1994, the FHWA sponsored a series of informational briefings on
Subsurface Utility Engineering (SUE). These one-day briefings were held
in the five largest TXDOT Districts. The briefing team was comprised of
Paul Scott (FHWA Headquarters), Lee Gibbons (FHWA Division), Joe Bissett
(MDSHA), and Jim Anspach (So-Deep).

As a result of these briefings, TXDOT began the process of developing a
SUE program. The Right-of-Way Division was the spearhead for this
program after hearing about SUE from the briefings and the conferences.
The Right-of-Way Division was able to initiate SUE knowing that the
design benefits would result in SUE becoming a part of the total project
process.

In 1995, a Request-for-Proposals (RFP) was published. In 1997, four SUE
providers were selected to provide Quality Level B (QL B) and Quality
Level A (QL A) mapping services on a state-wide basis. Initial, combined
contract values of \$4,000,000 over two years were increased to
\$9,000,000 over 28 months due to good results and the subsequent
internal demand.

In 1999, six new contracts totaling \$9,000,000 were let for a 3-year
term. The SUE program in Texas depends on the district involved and is
limited to Interstate (On-System) projects with no municipal or local
projects involved. SUE in Texas may be used on any construction project
on the state highway system. It is TXDOT\'s intent to encourage their
engineering design consultant community to begin using Subsurface
Utility Engineering on these Off-System projects that are more urban in
nature, and therefore potentially more utility-complex. TXDOT is now
firmly committed to SUE and plans to encourage its use in all districts.

When SUE was initially utilized in Texas in 1997, the Right-of-Way
Division began to develop an informal review procedure. This informal
procedure is accomplished by mutual agreement and judgment among the
Right-of-Way Division, design, and area engineers on an *as needed
project basis* regarding the extent of underground utilities, potential
impact, and engineering judgment. After the need for SUE is *scoped* by
the Right-of-Way Division, the particular district working with the
Right-of-Way Division in a team effort decides on the need for SUE. The
SUE contract is then administrated from the Right-of-Way Division who
manages the contracts with the 6 SUE providers (6 as of August 1999).

As of October 14, 1999, 146 SUE projects have been accomplished in
Texas. Now that many of the design and area engineers have become
familiar with the concepts of SUE, the informal process is working well.

Twenty-seven (27) projects were studied in detail to collect data and
information on time, cost, user, and risk management savings. The
evaluation study was then able to compute a cost savings of \$4.27 for
every dollar expended for SUE. In this study, SUE is considered to be
the use of Quality Level A and Quality Level B Utility Data, as opposed
to the traditional Quality Level C and Quality Level D Utility Data.
Based on the SUE savings analysis, a projected savings of \$108,308,000
is the potential savings to the Texas DOT statewide, if all projects
utilize Quality Level B and Quality Level A data, based on the amount of
highway construction typically under contract. Based on Fiscal Year 99
construction contract amounts and current performance levels from SUE
providers, the potential current annual savings is projected to be
\$66,092,000.

[]{#conclusions .anchor}**Conclusions**

The Federal Highway Administration (FHWA) commissioned Purdue University
to study the effectiveness of subsurface utility engineering (SUE) as a
means of reducing costs and delays on highway projects. From a study of
71 projects with a combined construction value in excess of \$1 billion,
the results indicated the effectiveness of the study was a total of
\$4.62 in savings for every \$1.00 spent on SUE. The costs of obtaining
QL B and QL A data on these 71 projects were 0.5 percent of the total
construction costs, resulting in a construction savings of 1.9 percent
by using SUE. Qualitative savings were non-measurable, but it is clear
that those savings are also significant and may be many times more
valuable than the quantifiable savings.

This is somewhat less than the \$7.00 to \$1.00 (previous VDOT study),
\$18.00 to \$1.00 (previous MDSHA study), and \$10.00 to \$1.00 (Society
of American Value Engineers) returns on investment that were previously
reported in literature. However, the quantity of studied projects is
much higher; the projects are more random in nature; and no qualitative
costs were included in the total. Indeed, one individual project had a
\$206.00 to \$1.00 return on investment (NCDOT). Only three of 71
projects had a negative return on investment. This leads to the
conclusion that SUE is a viable technologic practice that reduces
project costs related to the risks associated with existing subsurface
utilities and should be used in a systemic manner. Using the SUE savings
factor data from this study and a national expenditure in 1998 of \$51
billion for highway construction that was provided by the FHWA, the use
of SUE in a systemic manner should result in a minimum national savings
of approximately \$1 billion per year.

[]{#recommendations .anchor}**Recommendations**

There are several recommendations on state DOT subsurface utility
engineering programs that can be justified based upon the following
factors.

-   A review of many state DOT subsurface utility engineering programs.

-   Conversations with state and private practice engineers.

-   A review of available literature.

-   Personal attendance at many national, regional, and local functions
    pertaining at least in part to subsurface utility engineering over
    the past three years.

Some state DOT programs already incorporate these recommendations as
common practices. Other states should consider implementing them in
whole or part in order to keep up with the evolving field of subsurface
utility engineering, the proven cost savings that result from such
practices, and the changing liabilities created from existing subsurface
utilities.

These recommendations are in no particular order:

-   Establish subsurface utility engineering as a pre-qualification
    category for engineering services. Use appropriate criteria as a
    basis for pre-qualification. Remember that the FHWA, AASHTO, and the
    ASCE among others all consider this a professional engineering
    service with multi-disciplinary aspects.

-   Develop statewide, regional, and/or District subsurface utility
    engineering contracts for DOT in-house and/or consultant-designed
    projects.

-   Consider including subsurface utility engineering as a
    prequalification category in consultant RFPs.

-   Administer or make components of subsurface utility engineering
    available within the appropriate DOT organizational sections. For
    example, utility mapping and utility avoidance consulting is best
    performed within the Design section; utility coordination and
    utility relocation design may be more appropriate within the
    Right-of-Way/Utility sections. Preliminary utility cost estimates
    may be appropriate in the Project Planning section. Utility
    as-builting, utility damage prevention assistance, pre-bid utility
    data communication, and claims assistance may be appropriate in the
    Construction section.

-   Consider upgrading all projects to QL B and QL A data as a project
    self-insurance mechanism. This study shows that the benefits far
    exceed the costs on average. Trying to select only those projects
    that may end up with significant utility problems is risky at best.

-   Consider unit pricing for utility mapping functions as a contract
    mechanism. It is easy to administer, easy to audit for billing
    accuracy, and easy to budget estimated project costs.

-   Develop a program of continuing education for DOT design personnel
    and constructors on subsurface utility engineering and its benefits.

-   Consider utilizing all aspects of subsurface utility engineering
    rather than only the utility mapping component (see Virginia DOT\'s
    program).

-   Remain abreast of new developments in the field, e.g., American
    Society of Civil Engineers\' pending national standards, AASHTO\'s
    Best Utility Practices Guide, etc.

-   Encourage Local/Municipal Planning Organizations to use subsurface
    utility engineering. Their projects are usually more urban in nature
    and can accrue generally higher benefits than rural projects.

-   On plans, place a general note that spells out that subsurface
    utility engineering utility mapping Quality Levels B and A were
    utilized on this project. The type and existence of utility quality
    levels should also be indicated in the legend.

[]{#more .anchor}**More Information**

Free copies of the entire report may be obtained from:

Paul Scott\
Highway Engineer (Utilities Coordinator)\
Federal Highway Administration\
Office of Program Administration (HIPA-20)\
400 Seventh Street, SW., Room 3134\
Washington, D.C. 20590\
(202) 366-4104\
(202) 366-3988 fax\
paul.scott@fhwa.dot.gov