Scenic Trail Viewshed Protection Act This bill authorizes the Federal Energy Regulatory Commission (FERC) to issue a certificate of public convenience and necessity for a natural gas pipeline project that crosses or impacts the view from a national scenic trail under certain conditions. Specifically, FERC may issue such certificate only if it determines that the pipeline is the only alternative to meet an overriding public need; the applicant considered alternatives in order to result in no, or minimal, adverse effect to the trail; minimal road construction will be required to construct and operate the pipeline; construction of the pipeline will use the best available technology in order to minimize the potential for leakage; the pipeline will intersect the trail at a point that already has significant infrastructure crossing and only crosses the trail once; the pipeline will not affect the viewshed of a trail in an area of high conservation, recreational, or scenic value, a protected wilderness area, an old-growth forest or alpine area, or the designated location for a shelter or campsite; construction techniques for the pipeline will produce a minimal disturbance to the trail and surrounding conserved lands; plans for the ongoing maintenance and operation of the pipeline ensure that it is done in a way that minimizes impact on the trail; and the applicant acknowledges that it has a duty to protect the trail and ensure the health and safety of the public who use such trail and the surrounding environment.