When a line section can’t be effectively repaired and re-sagged, measured against FEMA’s damage thresholds. Eligible sections can be replaced with #2 ACSR conductor, or with advanced conductors where codes are adopted or through mitigation or an improved project.
You define the line section: a single span, all spans between dead-end structures, a feeder, a tap or any contiguous group. Adjustments to accommodate #2 ACSR, such as span lengths and pole heights, are eligible without citing a code. If no threshold is met, only repair is eligible.
A signed, stamped letter from a licensed engineer with direct system experience certifying pre-disaster capacity and condition, with maintenance records, work plans, any RUS corrective action plans and staking sheets. Source: PAPPG Table 29.
Choose line sections strategically. A well-drawn section can meet a threshold that the whole feeder averages out of.