Guidelines
Per the
Utility Accommodation Rules §21.37(e)
, “(1) The attachment of utility lines to bridges and grade separation structures is prohibited if other locations are feasible and reasonable. (2) Where other arrangements for a utility line to span an obstruction are not feasible, the utility may submit a request to the District for attachment of the line to a bridge structure through a bridge attachment agreement. Each attachment will be considered on an individual basis, and permission to attach will not be considered as establishing a precedent for granting of subsequent requests for attachment.”The following guidelines govern attachment of utilities to bridges.
Communication Lines
When it is impractical to carry a self-supporting communication line across a stream or other obstruction,
the
department may
permit the attachment of the line to a bridge. If approved on existing bridges, the line must be enclosed in a conduit and so located on the structure as not to interfere with stream flow, traffic, or routine maintenance operations. When a request is made before construction of a bridge, if approved, suitable conduits may be provided in the structure if the utility bears the cost of all additional work and materials involved.
If it is the department’s responsibility to provide for the adjustment of communications lines or conduits to accommodate the construction of a highway and the adjustment provides for the placement of communications conduits in a bridge, the department will allow a reasonable number of spare conduits in the structure if the spares are placed at the time of construction and the telephone company bears the cost of the spare conduits.
Gas or Fuel Lines
No gas or liquid fuel lines may be attached to a bridge or grade separation structure without the specific approval of the TxDOT Executive Director.
Power Lines
Power lines are not permitted on bridges under any condition with the exception of low-voltage distribution lines where the cost of independent facilities to carry these lines would be prohibitive. For this requirement, low-voltage lines must carry 600 volts or less.
Utility Pipelines
When a municipality or utility company requests permission to attach a pipeline to a proposed bridge prior to construction, and the added load is sufficient to require an increase in the strength of the structure or use of more costly materials or type of construction, the utility owner is required to pay for the increase in cost.
When a utility company requests permission to attach a pipeline to an existing bridge, sufficient information should be furnished to allow a stress analysis to determine the effect of the added load on the structure. Other details of the proposed attachment as they affect safety and maintenance should also be presented. If the bridge structure is not of adequate strength to carry the increased weight or forces within a factor of safety, permission will not be granted.
Temporary Water Lines or Saltwater Pipelines
Temporary water lines are sometimes requested to be attached to bridges by companies in the oil and gas industry. When a company requests permission to attach a temporary water line to an existing bridge, sufficient information should be furnished to perform a stress analysis to determine the effect of the added load on the structure. Other details that affect safety and maintenance of the proposed attachment should also be presented. Details of the proposed attachment to the bridge should be signed and sealed by a Texas registered professional engineer. If the bridge structure is not of adequate strength to carry the increased weight or forces within a factor of safety, permission will not be granted.