National Park Service: Process Exists for Prioritizing Asset Maintenance Decisions, but Evaluation Could Improve Efforts, GAO-17-136: Published: Dec 13, 2016. Publicly Released: Jan 12, 2017.

At the end of fiscal year 2015, the National Park Service reported $11.9 billion in deferred maintenance—that is, the estimated costs of asset maintenance or repairs that the agency has postponed for more than a year and has not yet resolved. To address its maintenance needs, the agency has determined that its highest priority assets—assets that are critical to the operation of parks—should be considered first for funding to keep them in good condition. The agency has not yet evaluated this approach and does not have plans underway to do so. We recommend that the Park Service evaluate whether this approach is working or if changes are needed.”

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