S.U.E
Subsurface Utility Engineering
***Coming Fall 2008***
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.
Levels of Quality
- 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.
Benefits of SUE
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.
Consider Alabama Utility Protection Services for your SUE Consultant in 2008!
