Democrats and Republicans both are in hand-wringing mode over the deterioration of America’s roads, bridges, airports and railways. If they are serious, eliminating unnecessary regulatory barriers would accelerate construction and stretch taxpayer dollars.

Among the worst of these regulations is the National Environmental Policy Act (NEPA), which persists despite dramatic changes in America’s economic, social, political, and environmental landscapes in the nearly 50 years since enactment. Its flaws are uncorrectable — arbitrary standards, politicized enforcement and protracted litigation (measured in decades).

The statute requires federal agencies to assess the potential environmental effects of public works projects and other major government actions. Agencies must consider the aesthetic, historic, cultural, economic and social effects of proposed actions. This overly broad mandate provides virtually endless opportunities for bureaucratic wrangling and legal challenge.

Its applicability is broad, encompassing government financing, technical assistance, permitting, regulations, or federal policies and procedures that touch a project. Every executive branch department must comply, and individual projects often include multiple agencies.

The NEPA text is relatively brief — 3,200 words — but compliance is complex. For example, “The NEPA Book: A Step-by-Step Guide on How to Comply with the National Environmental Policy Act,” runs 475 pages long. Compliance is rendered all the more difficult by the fact that each federal agency imposes its own NEPA procedures, and projects may face multiple sets of rules.

Activists use judicial review of NEPA assessments to delay projects. The mere filing of a lawsuit and the delays that result are often as important to activists as whether they ultimately prevail in court. The likelihood of litigation prompts agencies to prepare litigation-proof assessments in hopes of staking a defensible position (and avoiding public embarrassment). This generates exhaustive demands for data — about which companies trying to secure a federal permit are in no position to complain.

The average time to complete a NEPA impact assessment of a transportation project has expanded from 2.2 years in the 1970s to 6.6 years in 2011 — and that’s just one of several permitting hurdles. Every delay increases project costs and postpones the benefits of modern — and safer — infrastructure for little or no environmental benefit.

No one tracks NEPA compliance costs, nor does the process involve any comparison of costs to benefits. And few agencies conduct retrospective reviews to determine the accuracy of the environmental forecasts that drive project design. (A 1987 study of 239 environmental impact statements found that forecasts were generally “not inaccurate,” although many were “accurate” solely by virtue of “vagueness and generalities.”)

The NEPA is rendered largely pointless by the number of “categorical exclusions” that agencies grant to waive environmental review. The Federal Highway Administration alone lists more than 50 types of such exclusions, and waivers constitute between 90 percent and 99 percent of the NEPA decisions involving state transportation programs. But a good many other projects languish for years in the NEPA’s bureaucratic and judicial purgatory.

At one time, the NEPA represented the statutory vanguard for environmental regulation. Today, however, the regime is redundant; there is no shortage of federal and state regulations to protect water and air quality, to preserve wetlands and endangered species, and to control run-off, hazardous waste, construction debris, demolition dust, and every other byproduct of infrastructure modernization.

Congress has tinkered with marginal reforms in several statutes, and the Council on Environmental Quality has issued more than 35 sets of guidelines on NEPA implementation — all of which have made the review process unpredictable and inordinately politicized.

President Trump’s infrastructure plan features 15 pages of recommendations to streamline permitting. The very fact that so many provisions warrant reform illustrates that there is more wrong than right with the NEPA, and thus its repeal is warranted.

Repealing the NEPA would not make a whit of difference to the environment or public health. It would reduce regulatory delays and permitting costs, and expedite the repair of teeth-rattling roads, deteriorating bridges, and timeworn rails and runways.