In its recent “DIRT Report,” the Common Ground Alliance featured an interactive tool that showed sobering year-to-year statistics on the frequency of underground utility strikes during excavation work. In 2023, 167,000 unique underground facility strikes occurred in the United States, with nearly 50 percent of those incidents occurring because either there was no effort to locate underground utilities, or they were mis-located. 

The Association of General Contractors’ 2024 “Utility Infrastructure Division Survey” revealed that of contractors who hit underground utilities, in 64 percent of those strikes, the utility was more than two feet outside of the area marked. In over 20 years of this practice, more than $1.7 billion in property damage, thousands of injuries and hundreds of deaths have occurred, all seemingly preventable. However, despite exposure to this issue, something about underground excavation work evades easy understanding. The evolution of underground utility law from a patchwork of local ordinances to today’s complex web of federal mandates, state statutes, and industry standards makes for an opaque outlook. Behind each of these statistics lies a potential lawsuit that could fundamentally alter a contractor’s business trajectory.

LEGAL FRAMEWORK OF UNDERGROUND DETECTION

The modern legal framework governing underground utilities rests on three foundational pillars: federal pipeline safety regulations, state “one-call” statutes, and local excavation ordinances. At the federal level, the Pipeline and Hazardous Materials Safety Administration (PHMSA) sets baseline safety standards for natural gas and hazardous liquid pipelines. Federal regulations under 49 CFR § 196.103 establish mandatory excavation protocols that extend beyond simple one-call notification requirements. The regulation requires excavators to not only initiate local one-call notifications but also to wait for pipeline operators to physically arrive on-site to establish and mark their facilities before beginning excavation work. Crucially, the regulation mandates that excavators must “take all practicable steps to prevent excavation damage,” once markings are established. Courts interpret this language as creating an affirmative duty of care that goes beyond mere passive compliance. The regulation requires additional one-call notifications as excavation progresses, recognizing that initial markings may become inadequate as work conditions change. This federal framework does not preclude additional state law duties or immunize contractors from negligence claims when circumstances demand heightened care.

Real legal complexity emerges at the state level. State one-call statutes vary significantly in their specifics, and these differences matter enormously in litigation. As an example, in Illinois, their JULIE statute provides a two-business-day safe harbor for utility marking, while California’s Underground Service Alert system requires three working days. More critically, states differ in their approach to liability allocation. Some jurisdictions have adopted comparative fault systems that apportion damages based on each party’s degree of responsibility, while others maintain traditional negligence frameworks that can result in all-or-nothing liability determinations.

THE DUTY OF INDEPENDENT VERIFICATION

While compliance with one-call requirements provides important legal protection, courts increasingly recognize that statutory compliance alone may not satisfy the duty of reasonable care, particularly in high-risk excavation scenarios. In fact, contractors may have an independent duty to verify utility locations when circumstances suggest that provided markings may be incomplete or inaccurate. Titan Earthwork, LLC v. City of Federal Way, 403 P.3d 884 (Ct. App. Wash. 2017), held that even though lines were marked, the contractor was still liable for damaging underground utilities because they “failed to determine the utility line’s ‘precise location.’”

This creates what can be called a “red flag doctrine,” when obvious warning signs exist, contractors cannot blindly rely on utility markings. These red flags include discrepancies between as-built drawings and field conditions, evidence of recent utility work in the excavation area, disturbance of the prior markings, or the presence of utility structures that obviously don’t align with provided markings. In densely developed urban areas, the duty of independent, precise verification becomes particularly pronounced.

Advanced detection methods such as ground-penetrating radar, electromagnetic locating, and 3D subsurface imaging are transitioning from optional best practices to legally expected standard procedures. Contractors who eschew these technologies may find themselves at a disadvantage in negligence determinations, or worse, as in the case above, found strictly liable, particularly when the additional cost would have been modest compared to the damage ultimately caused.

UTILITY OWNER RESPONSIBILITIES

Utility owners face equally complex legal obligations that create opportunities for liability shifting in damage cases. These responsibilities generally fall into three categories: record maintenance, system marking, and damage response.

Record maintenance obligations require utilities to maintain reasonably accurate maps and documentation of their infrastructure. A utility’s failure to update records after relocating utility lines may create liability when a contractor, relying on outdated information, struck the moved line. The marking obligation extends beyond simply painting lines on pavement. Utilities must provide markings that reasonably identify their facilities’ location within statutory tolerance requirements, typically 18-24 inches on either side of the actual utility. When markings are absent, inaccurate, or misleading, utilities may face primary liability for resulting damage. Further, they should insist on “as-built” drawings from their project design team, and make sure to timely provide those documents to the appropriate state and local monitoring agencies to update their databases. 

CONTRACTUAL RISK ALLOCATION AND INSURANCE STRATEGIES

The interplay between statutory liability and contractual risk allocation creates opportunities for sophisticated risk management through careful contract drafting. However, indemnification clauses require nuanced understanding of both construction law and insurance coverage principles.

Some states have enacted anti-indemnity statutes that void contractual provisions requiring parties to indemnify others for their own sole negligence. More effective is the trend toward utility-specific insurance requirements and dedicated utility strike coverage. Traditional commercial general liability policies often contain exclusions for subsurface work, while specialized utility strike insurance provides broader coverage and access to specialized defense counsel.

Risk allocation also extends to project delivery methods. Design-build contracts may shift utility location responsibilities to contractors, while traditional design-bid-build approaches typically leave utility coordination with design professionals. Each approach creates different liability profiles that must be considered during project planning.

EMERGING TRENDS

Several trends are reshaping utility strike liability. The increasing prevalence of fiber optic and telecommunications infrastructure has created new categories of high-value targets with complex ownership arrangements. Climate change infrastructure investments are creating denser underground environments with higher damage potential. The push toward smart city infrastructure and 5G networks is driving installation of smaller, more numerous underground assets that are harder to detect and mark.

Additionally, the construction industry’s labor shortage is creating pressure to accelerate excavation timelines and rely more heavily on automated equipment, both trends that increase utility strike risk and may affect legal standards for reasonable care.

PRACTICAL RISK MANAGEMENT STRATEGIES

Drawing from three decades of utility strike litigation, several risk management principles have proven consistently effective across jurisdictions and project types.

Pre-Project Intelligence Gathering represents the most effective risk mitigation. This includes not only standard one-call notifications but also direct coordination with utility owners, review of available as-built documentation, and site reconnaissance to identify surface indicators of underground infrastructure. In complex projects, engage utility coordination specialists who maintain relationships with local utility owners and understand regional infrastructure patterns.

Technology Integration should be viewed as insurance, not overhead. The cost of comprehensive subsurface utility engineering (SUE) services is typically a fraction of the potential damage from a major utility strike. More importantly, SUE documentation provides valuable evidence of due diligence in potential litigation.

Documentation Protocol serves both operational and legal functions. Photograph all markings before excavation begins, document any discrepancies or concerns, and maintain detailed excavation logs. When utilities are encountered unexpectedly, stop work immediately and document the situation thoroughly before proceeding. This documentation often determines litigation outcomes.

Emergency Response Planning should include developed and regularly updated procedures for utility strikes. Quick, appropriate response can minimize damage and demonstrate good faith efforts to mitigate harm, factors that influence both liability determinations and damage calculations.

CONCLUSION

Despite being unknown and unanticipated, there emerge recurring patterns in utility strike cases. Contractors should never rely solely on one-call markings in congested utility corridors or areas with obvious infrastructure complexity. They should verify their insurance coverage specifically addresses utility strike scenarios, including business interruption losses and coordination between multiple policies. On projects, they should document everything—the contractors who avoid liability consistently maintain comprehensive excavation records that demonstrate systematic risk management approaches. Finally, and most importantly, they should treat utility strike prevention as integral project planning, not just administrative compliance. Courts increasingly expect construction professionals to demonstrate active engagement with prevention, not passive compliance with minimum statutory requirements.

Underground excavation will always involve inherent risks that cannot be completely eliminated. However, understanding the evolving legal landscape and implementing comprehensive risk management strategies can significantly reduce both the probability of utility strikes and the legal consequences when they occur. Contractors who consistently avoid liability are those who approach subsurface risks with the same systematic methodology they apply to other project hazards. As our infrastructure becomes more complex, the importance of these principles will only increase.  

about the author

William Thomas is a principal at Gausnell, O’Keefe & Thomas, LLC in St. Louis, where he focuses his practice on construction claims and loss prevention. He is a member of the International Association of Defense Counsel (IADC), currently serving as chairperson of the IADC’s Construction Law Committee; an AAA Panel Arbitrator; a Fellow with the Construction Lawyers Society of America; and a member of the ABA Forum on Construction, AIA, and ASCE. He can be reached at wthomas@gotlawstl.com.