Minimizing Utility Issues During Construction: A Guide (2024)
Chapter: 2 Causes of Utility Issues During Construction
CHAPTER 2
Causes of Utility Issues During Construction
NCHRP Project 15-69 documented typical causes of utility-related issues affecting highway construction projects based on the results of a literature review, a national practitioner survey, and an analysis of a large sample of change orders and claim records.
Literature Review
The literature review focused on practices and issues related to utility-related impacts on project delivery as well as construction and utility inspection practices. Common factors mentioned included utility relocation delays; different site conditions (DSCs); errors in plans, specifications, and estimate (PS&E); and owner-requested changes.
Some studies used change order and claim data to examine the impact of utility-related issues on project delays and cost overruns. For example, one study found a little over 5 percent of change orders were related to utility conflicts. Another study reviewed utility cut damages and noted that utility facility damages caused contractor delays in 30 percent of projects. One of the reasons for utility-related delays was inaccurate or inexistent location data about utility facilities. A federal review found that lack of adequate data about existing utility facilities caused utility conflicts to be misidentified or not identified prior to construction, resulting, in turn, in contractors finding utility facilities unexpectedly during construction and causing project delays.
Other than participation in surveys and interviews, the technical literature was scant on the impact of utility-related issues to contractors. Examples that were noted included (a) lower production rates for installing underground appurtenances that were in conflict with existing or unknown utility facilities; (b) increased costs because of the need to work around existing utility facilities that had not been relocated; (c) crew delays while waiting on decisions regarding unknown utility facilities; and (d) having to schedule work during more expensive seasons or to push the overall construction schedule into the next construction season.
A total of 29 state departments of transportation (DOTs) had specific requirements for construction or utility inspections on their websites. It is common to require as-builts depicting the location of existing and relocated utility facilities within the right-of-way. In some cases, DOTs require as-built files to be tied to project control points or global navigation satellite system (GNSS) coordinates. It is common not to require utility owners to submit as-built files if there is not a significant deviation from plans, specifications, locations, and conditions. In some cases, utility owners must submit an affidavit or certification that there is not a significant deviation from the original plans. However, if the deviation from the original plans is substantial, the utility owner must submit as-built files showing actual locations, types, and sizes.
For utility relocations that are included in the highway contract, DOTs typically apply standard inspection and survey accuracy procedures. Some DOTs have specific data collection
requirements for stormwater facilities (which DOTs typically own) and utility facilities that are included in the highway contract.
Practitioner Survey
A national survey identified risk factors affecting the utility process during the project delivery process, primarily during construction. The survey instrument included a list of 61 risk factors. Respondents were asked to rate risk factors on a scale from 1 (least frequent) to 5 (most frequent) in terms of how frequently the risk factors contribute to project delivery delays, project cost increases, and utility relocation delays.
Table 1 shows the top 20 utility-related risk factors that, according to respondents, contributed most often to project delays, cost overruns, and utility relocation delays. The table shows average ratings for each stakeholder group represented in the survey. For visualization, table cells are
Table 1. Top 20 utility-related risk factors by stakeholder group.
| Risk Factor | Project Owner | Consultant | Contractor | Utility Owner | Average |
|---|---|---|---|---|---|
| Differing site conditions (new utility conflicts or utility conflicts that were not resolved properly during design) | 3.4 | 3.5 | 4.5 | 3.1 | 3.7 |
| Delays in acquiring critical parcels (e.g., parcels on eminent domain or parcels needed for utility relocations) | 3.4 | 4.0 | 4.4 | 3.4 | 3.7 |
| Delays in getting utility owners to respond and begin coordination | 3.5 | 3.6 | 4.2 | 3.1 | 3.7 |
| Inaccurate or incomplete utility facility data during design | 3.4 | 3.7 | 4.3 | 2.9 | 3.6 |
| Errors in plans, specifications, or cost estimates | 3.4 | 3.3 | 4.4 | 3.2 | 3.6 |
| Delays in getting utility owners to schedule utility relocations in the field | 3.4 | 3.7 | 4.2 | 2.8 | 3.6 |
| Delays in acquiring all parcels | 3.2 | 3.9 | 4.2 | 3.0 | 3.5 |
| Changes in highway design prior to letting | 3.4 | 3.6 | 3.6 | 3.2 | 3.5 |
| Unrealistic timeframe by project owner for utility coordination and utility relocations | 3.1 | 3.5 | 3.8 | 3.6 | 3.4 |
| Delays in identifying and resolving utility conflicts | 3.1 | 3.3 | 4.1 | 2.9 | 3.3 |
| Delays in acquiring replacement easements for utility relocations | 3.0 | 3.7 | 4.0 | 3.1 | 3.3 |
| Inadequate utility relocation schedule | 3.2 | 3.3 | 4.0 | 2.5 | 3.3 |
| Utility owners holding off on relocation design until right-of-way has been acquired | 3.1 | 3.3 | 3.8 | 3.2 | 3.3 |
| Unrealistic timeframe by utility owner for completing utility relocation work in the field | 3.1 | 3.4 | 3.6 | 2.6 | 3.3 |
| Utility owners holding off on relocation design until project plans are at least 60% or 90% complete | 3.1 | 3.2 | 3.9 | 3.3 | 3.3 |
| Delays in obtaining permits (e.g., U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers, and so on) | 3.0 | 3.4 | 4.2 | 3.5 | 3.2 |
| Inadequate coordination or sequencing among utility owners using common poles or duct banks | 3.0 | 3.3 | 3.8 | 2.7 | 3.2 |
| Delays in getting responses from utility owner when there are highway construction changes that necessitate coordination | 2.9 | 3.3 | 3.9 | 2.3 | 3.2 |
| Inadequate utility relocation plans | 3.0 | 3.0 | 4.1 | 2.4 | 3.2 |
| Right-of-way encroachments or features impeding utility relocations | 2.7 | 3.6 | 3.6 | 3.0 | 3.1 |
color coded using a continuous gradation, with white used for the lowest value (i.e., 1.0), yellow used for the midpoint value (i.e., 3.0), and red used for the highest value (i.e., 5.0).
The scatterplot of average ratings versus standard deviations in Figure 1 shows that standard deviations are lower for either low or high average ratings than for mid-range average ratings, showing more agreement among respondents with respect to factors that were either low risk or high risk. Agreement among respondents was particularly strong for high-risk factors.
Change Order and Claim Trends
The analysis of change orders and claims was based on a large sample that included more than 150,000 change order and claim records from six state DOTs. Classification of records as utility-related (UR) or non-utility-related (NUR) involved using common UR terms, reviewing the description and justification columns of each change order, and using artificial intelligence (AI) models to detect trends and patterns. The total number of UR change orders for the six cases was 11,803.
Further analysis of UR records involved classifying each record according to a list of nine disaggregated reasons. For each case, Table 2 shows the percentage of UR change orders per disaggregated change order reason. The table also shows the overall average for all cases.
The results in Table 2 point to two major groups of reasons behind UR change orders:
- Reasons behind a substantial number of UR change orders (79 percent in total):
- Errors and omissions in PS&E (33 percent).
- Inaccurate or incomplete data about existing or relocated utility facilities (23 percent).
- Changes initiated by project owner, contractor, or utility owner (12 percent).
- Delays in getting utility owners to schedule utility relocations (11 percent).
- Reasons behind a small number of UR change orders (21 percent in total):
- Differing site conditions (4 percent).
- Difficult or inadequate constructability of highway work or utility relocation (4 percent).
- Inaccurate or deficient utility relocation work (2 percent).
Table 2. Percentage of UR change orders per disaggregated change order reason.
| Disaggregated Change Order Reason | Case 1 | Case 2 | Case 5 | Case 6 | Case 8 | Case 9 | Average1 |
|---|---|---|---|---|---|---|---|
| Errors and omissions in PS&E | 33.6% | 25.9% | 50.2% | 33.1% | 13.1% | 32.0% | 32.7% |
| Inaccurate or incomplete data about existing or relocated utility facilities | 24.5% | 1.0% | 14.1% | 16.4% | 9.7% | 28.1% | 22.8% |
| Changes initiated by project owner, contractor, or utility owner | 10.5% | 7.1% | 9.6% | 18.9% | 17.7% | 9.2% | 12.4% |
| Delays in getting utility owners to schedule utility relocations | 1.4% | 32.0% | 4.3% | 11.0% | 41.8% | 12.1% | 11.2% |
| Differing site conditions | 3.3% | 33.5% | 6.3% | 4.9% | 5.9% | 2.7% | 4.2% |
| Difficult or inadequate constructability of highway work or utility relocation | 3.3% | 0% | 3.9% | 5.3% | 5.5% | 3.0% | 3.7% |
| Inaccurate or deficient utility relocation work | 2.2% | 0% | 1.5% | 2.5% | 1.3% | 2.1% | 2.2% |
| Delays in acquiring or clearing right-of-way or utility relocation sites | 2.0% | 0% | 0.7% | 1.7% | 0.8% | 2.1% | 1.9% |
| Other | 19.2% | 0.5% | 9.3% | 6.2% | 4.2% | 8.7% | 9.0% |
| Total | 100% | 100% | 100% | 100% | 100% | 100% | 100% |
1 Average percentage was calculated using the total number of UR change orders for each disaggregated change order with respect to the overall total of UR change orders.
- Delays in acquiring or clearing right-of-way or utility relocation sites (2 percent).
- Other (9 percent).
This differentiation has significant ramifications for the identification of potential strategies for implementation. First, except for utility relocation delays caused by utility owners (12 percent of UR change orders), most reasons that cause a substantial number of UR change orders are reasons that a DOT can control, specifically, errors and omissions in PS&E (33 percent) and inaccurate or incomplete data about utility facilities (23 percent). These two reasons account for 56 percent of UR change orders.
Second, most reasons behind a substantial number of UR change orders are reasons that a DOT could address prior to letting, which highlights the importance of conducting utility investigations and identifying and resolving utility conflicts during the preliminary design and design phases. Overall, the results in Table 2 show that pursuing these two strategies systematically could have a positive impact on 60 to 80 percent of UR change orders.
For DOTs where the change order description was sufficient (i.e., Cases 1, 5, 6, 8, and 9), the number of UR change orders classified as DSCs was low. For those states, it was possible to identify the actual reason behind the change order (even if the DOT had originally classified the change order as a DSC). This result is significant because it could point to many cases in which a change order might be classified as a DSC for convenience or because the official in charge did not have more meaningful categories from which to choose, but the actual reason was completely different.
Other reasons listed in Table 2 also had a small number of UR change orders. One of those reasons was difficult or inadequate constructability of highway work or utility relocation. It is likely that one of the main reasons is that the number of complex utility relocations is low in most projects and that highway contractors are often able to predict complex situations while preparing the bid for the project. Likewise, the number of UR change orders attributed to delays in acquiring or clearing right-of-way or utility relocation sites was low. Reasons include that DOTs often acquire all the necessary parcels before the project is let and that highway contractors know about the pending parcels while preparing the bid and plan their sequence of work accordingly.
