Excavation and trenching - Utah

Utah operates an OSHA-approved State Plan covering most private sector workers and all state and local government workers. Federal OSHA covers most issues not covered by the Utah State Plan. The Utah Occupational Safety and Health Division (UOSH) is part of the Utah Labor Commission.

Underground facilities

UOSH requires any excavator to notify the operator of underground facilities (buried utilities) at least 24 hours before excavating and comply with Utah Code Ann. §§ 54-8a-1 through 54-8a-13, entitled Damage to Underground Utility Facilities. The notice must be given by telephone, electronic communication, or by other acceptable means to the association of operators organized to receive notification of excavation in the state. This allows operators an opportunity to locate and mark their underground facilities to prevent damage, interruption of service, or injury to excavation workers.

Utility construction

Drainage facilities. The utility company must avoid disturbing or damaging existing highway drainage facilities and is responsible for repairs, including restoration of ditch flow lines. Wherever necessary, the utility company must provide drainage away from its own facilities to avoid damage to the highway.

Facilities in the right of way. Any utility facilities located within the right of way must be adequately maintained. Any physical modifications, relocations, additions, excavations, or impedance of traffic within the right of way will require the submittal of a new encroachment permit application. No utility construction work may begin until the new encroachment permit is approved.

Restoration. Restoration of the highway right of way disturbed by excavation, grading work, or other activities must include reseeding and restoration of existing landscaping. Any areas that are denuded of vegetation because of construction or maintenance must be reseeded, which is subject to inspection and acceptance by UDOT.

Open trench construction traversing rights of way. Open trench utility installations are not permitted unless an acceptable trenchless method is unfeasible, such as in unsuitable soil conditions or extremely difficult rock. UDOT may also grant a deviation from requiring trenchless construction where older pavement is severely deteriorated.

Limited impact on traffic. Open trench construction on rights of way is limited to areas where traffic impacts are minimal. Any pavement structure broken, disturbed, cut, or otherwise damaged in any way must be removed and replaced to a design equal to or greater than the surrounding undisturbed pavement structure, or as otherwise determined by UDOT.

Restoration and maintenance. For open trench installations, the utility company is responsible for the restoration and maintenance of the pavement structure for three years as outlined in Subsection R930-7-6(6)(b), unless a deviation from this rule as outlined in Section R930-7-13 is granted by UDOT.

Failure to repair pavement. When the utility company or its contractor performing the utility construction work is not equipped or fails to properly repair the damage to the pavement structure, UDOT will repair the damage and bill the utility company for the actual costs incurred, including any administrative costs. Any pavement restoration work performed by the utility company shall be completed within 48 hours after completion of the excavation and backfill.

Open trench utility installations

Standards. Any open trench utility installations must conform to the applicable provisions of the current UDOT Standard Specifications for Road and Bridge Construction.

Restoration. It is the utility company’s responsibility to restore the structural integrity of the roadbed, secure the utility facility against deformation and leakage, assure that the utility trench does not become a drainage channel and that the backfilled trench doesn’t impede or alter road drainage.

Vertical faces. Trenches must be cut to have vertical faces. Maximum width must be two feet or the outside diameter of the pipe plus one and one-half feet on each side. Any trenches must be shored where necessary and meet OSHA requirements.

Bedding. Bedding must be provided to a depth of one-half the diameter of the pipe and must consist of granular material, free from rocks, lumps, clods, cobbles, or frozen materials, and be graded to a firm surface without abrupt change in bearing value. Unstable soils and rock ledges must be sub-excavated from beneath the bedding zone and replaced with suitable granular material.

Backfilling. Backfill must meet the current UDOT Standard Specification 02056 Embankment, Borrow and Backfill, and 03575 Flowable Fill. Additional specifications may be required by UDOT.

Pavement. Pavement replacement may be performed by either the utility company or a contractor engaged by the utility company. The Region Permits Officer will determine pavement replacement requirements. The utility company is liable for three years from the date of completion of the pavement replacement for the cost of repairs if the backfill subsides or the patched pavement fails.

Failure to repair. Where a utility company fails to properly repair any damage to the pavement structure, UDOT may repair the damage, and the costs, including administrative costs, will be the responsibility of the utility company.

Trenchless utility construction

Required whenever practicable. Trenchless utility installations are required for any utility crossings of highways or roadways, where practicable. This construction method is required to avoid disturbing the pavement surface, particularly where underground utilities exist on major highways, expressways, or freeways. Only UDOT-approved methods may be used to install a utility facility under a highway.

Pipeline installation. Any trenchless pipeline installations must extend under and across the entire roadway prism to a point five feet beyond the toes of the fore-slopes, borrow ditch bottom, or across the access-controlled right of way lines, but never less than 15 feet from the edge of pavement or a ramp.

Water jetting and tunneling. Water jetting or tunneling may not be used. Water-assisted or wet boring may be permitted if the utility company can demonstrate to UDOT through the deviation process outlined in Section R930-7-13 that the operation will not adversely impact the roadway and subgrade.

Size of operation. The size of a trenchless operation must be restricted to the minimum size necessary for the utility or pipeline installation and may not exceed the utility facility or pipeline diameter by more than 5 percent unless otherwise required based on equipment and product manufacturer’s specifications. Grout or flowable fill backfill must be used for carriers or casings and for over-breaks, unused holes or abandoned carriers or casings. The composition of the grout must be cement mortar, a slurry of fine sand or other fine granular materials.

Portals. Portals including surface openings and bore pits must be established safely beyond the highway surface and the clear zone to avoid impairing the roadway during installation of the pipeline.

Portal offset, shoring, and bulkheading. Where a bulkhead seals the pipeline portal, the portal must be suitably offset from the surfaced area of the highway. Shoring and bulkheading must conform to applicable federal, state, and local jurisdiction construction and safety standards. Where a bulkhead is not installed in the pipeline, the portal must be offset no less than the vertical difference in elevation between the surfaced area of the highway and the bottom of the bore pit.

Equipment set up and operation. The utility company must follow the manufacturer’s guidelines and industry standards for equipment set-up and operation. The utility company must assess soil conditions to determine the most appropriate installation technique. Subsurface bore paths must be tracked and recorded by the utility company, and any failed bores must be appropriately abandoned and backfilled by the utility company.

Drilling fluid containment and disposal. Drilling fluids must be prepared and used according to the fluid and drilling equipment manufacturer’s guidelines. The utility company must use fluid containment pits at both bore entry and exit points and must use appropriate operational controls to avoid heaving or loss of drilling fluids from the bore. Antifreeze additives must be non-toxic and biodegradable products. The utility company must dispose of drilling fluids and other materials in permitted facilities that accept the types of chemicals and wastes used in the trenchless operations.