Environmental review is the popular suspect when a highway project’s schedule dies. The regulation points somewhere else. Under 23 CFR 635.309, FHWA normally issues authorization to advertise construction for bids only after the plans, specifications and estimates have been approved, and only after the state supplies a statement that all right-of-way clearance, utility and railroad work is complete or arranged for proper coordination with the construction schedule, and a certification that every individual and family has been relocated to decent, safe and sanitary housing.

That is a single gate with three independent parties behind it. The state controls design. It does not control a utility company’s capital plan, a railroad’s engineering department, or a condemnation docket. Projects wait at this gate.

Two documents decide whether the project exists at all

Before any of that, a project has to be in the plan and then in the program, and the two are different instruments with different jobs.

The long-range plan comes first. Under 23 CFR Part 450, a state’s long-range statewide transportation plan carries a minimum 20-year forecast period at adoption, and a metropolitan transportation plan addresses no less than a 20-year planning horizon. Metropolitan plans are reviewed and updated at least every four years in air quality nonattainment and maintenance areas and at least every five years elsewhere, and each update extends the horizon back out to 20 years. The plan is a statement of intent. It does not have to be fiscally constrained at the statewide level.

The program is where money appears. A statewide transportation improvement program covers no less than four years, is updated at least every four, incorporates each metropolitan program without change once approved, and must be fiscally constrained. Projects are advanced to implementation from the first four years of an approved program. A project outside that program is not eligible for funding under title 23, whatever its engineering merit. How candidates get into it in the first place is the subject of how state DOTs decide which roads to rebuild.

Environmental review begins as a classification decision

The most consequential environmental determination on a highway project happens before any analysis, when the class of action is chosen.

23 CFR 771.115 sets out three classes and, importantly, says the administration may use any reliable data source to choose among them and is not required to undertake new scientific or technical research unless that research is essential to a reasoned choice among alternatives and the cost and time of obtaining it are not unreasonable. An environmental impact statement is required for actions with a reasonably foreseeable significant effect, and the regulation gives examples that read as bright lines for highway work: a new controlled access freeway, and a highway project of four or more lanes on new location. A categorical exclusion covers actions that normally have no significant environmental effect, drawn from the list in 771.117. Everything that is neither an impact statement nor an exclusion is an environmental assessment, and the assessment exists partly to determine which document is actually required.

FHWA also carries deadlines of its own at this stage. It must identify the probable class of action as soon as sufficient information exists to identify reasonably foreseeable impacts, and for projects to be evaluated with an impact statement it must respond in writing to a sponsor’s formal notification within 45 days. For projects under the 23 U.S.C. 139 process, agencies with an interest must be invited within 45 days of publication of the notice of intent.

The scoping rule that makes projects bigger

Buried in 23 CFR 771.111(f) is a three-part test that shapes highway projects more than any other clause in the environmental regulations. Whatever its class of action, a project must connect logical termini and be of sufficient length to address environmental matters on a broad scope, must have independent utility, meaning it is usable and a reasonable expenditure even if no other improvement in the area is made, and must not restrict consideration of alternatives for other reasonably foreseeable improvements.

The first clause prevents a corridor from being cut into segments small enough to escape meaningful review. The second prevents a segment that only makes sense as the first piece of something larger. Together they force sponsors to define projects at a scale where the consequences are visible, which is the point, and they also mean a project’s footprint is often larger than its sponsor would prefer. For genuinely major actions the regulation offers tiering, with a first-tier document addressing location, mode choice and areawide air quality and land use implications, and a second tier addressing site-specific impacts, costs and mitigation.

In 2023 Congress put a clock on the process

The Fiscal Responsibility Act of 2023, enacted June 3, 2023, rewrote a substantial part of the National Environmental Policy Act, and the amendments matter to anyone estimating a project schedule.

Lead agencies must complete an environmental impact statement within two years and an environmental assessment within one year. The clock runs from the earliest of three events: the date the agency determines a statement is required, the date it notifies the applicant that a right-of-way application is complete, or the date it issues the notice of intent to prepare the document. The act also imposed page limits, which is a blunter instrument than the deadlines and possibly more effective. An impact statement may not exceed 150 pages, or 300 pages for an action of extraordinary complexity, and an assessment may not exceed 75 pages, in each case excluding citations and appendices.

There is a remedy. A project sponsor may petition a court over an alleged failure to meet a deadline, and a court that finds the agency out of compliance must set a schedule and deadline for the agency to act as soon as practicable, not to exceed 90 days from the order unless a longer period is necessary to comply with applicable law.

Read the deadline provision closely, though, and its limits are structural rather than loopholes. The statute lets a lead agency that determines it cannot meet a deadline extend it, in consultation with the applicant, to provide only so much additional time as is necessary. More fundamentally, two of the three trigger events are things the agency itself does. Nothing in the section compels an agency to issue a notice of intent by a given date. The two-year limit therefore constrains how long review takes once it formally starts, and says nothing about the interval before it starts. Project delivery measured against these deadlines runs from the notice of intent, with everything before it counted separately.

Then 150 days to be really finished

A decision is not durable until the window for challenging it closes, and highway decisions have a short one. Under 23 CFR 771.139, implementing 23 U.S.C. 139(l), notices announcing decisions may be published in the Federal Register as final, and claims arising under federal law seeking judicial review of such a decision are time barred unless filed within 150 days of publication of the limitations-on-claims notice. For Federal Railroad Administration decisions the period is two years. The regulation is careful that this does not lengthen any shorter review period established elsewhere, and does not create a right of judicial review that would not otherwise exist.

For a sponsor, that notice is the moment the project becomes financeable in practice. For anyone tracking a contested corridor, it is the date to put in the calendar.

Where the time actually goes

Design phases consume calendar in a predictable, manageable way. The three stages that do not are all about other people’s property. Schedule risk across highway design coverage sits with organizations no highway agency controls.

Right of way is the largest. The certification conditions in 635.309 accept several states of completion. Full legal and physical possession is the clean case. The regulation also permits certification where litigation is pending on some parcels but right of entry has been obtained and occupants have vacated, and it permits a conditional certification where a few parcels remain incomplete but every occupant of a residence on them has had replacement housing made available under 49 CFR 24.204. On a conditional certification, FHWA will approve advertisement for bids unless it finds that proceeding before acquisition activities are complete would not be in the public interest. That graduated structure exists precisely because acquisition timelines are not controllable.

Utility and railroad coordination sits in the same sentence of the regulation and rarely gets the same attention. A relocation that depends on another organization’s construction season is a schedule risk the highway agency can influence and cannot command.

Fiscal constraint is the third, and it is the one that surprises people. A project can be fully designed, environmentally cleared, with right of way in hand, and still wait because the program year it needs is committed. Which is also the point at which the cost estimate prepared years earlier meets current bid prices, a collision examined in how much a mile of Interstate highway costs.

Two dates in the Federal Register, and the years before them

National averages for environmental review duration are widely quoted and worth distrusting, because the figure depends on the sample, on which projects are counted, and on whether the clock starts at the notice of intent or at the first planning study.

What is not in dispute is what the Federal Register itself records. The notice of intent carries a published date, and so does the record of decision or the finding of no significant impact. The interval between those two dates is the review period the 2023 deadlines govern, and it is a fact rather than an estimate. Before that interval starts, a project has usually already spent years in the long-range plan and then the program, and the 2023 amendments do not reach that earlier stretch. A national average that blends the two intervals together is measuring something the statute was never written to govern.

The amendments do reach accountability for the interval they cover. Each lead agency must report annually to the House Committee on Natural Resources and the Senate Committee on Environment and Public Works, identifying every assessment and impact statement it failed to complete by the deadline, explaining each failure, naming the office responsible, and stating the trigger dates. That report turns the aggregate question into a matter of record rather than inference, at least for the interval the deadlines actually cover.

How the resulting contract is then structured and let is taken up in highway project delivery methods, where the choice of delivery model changes which of these gates has to close before construction can begin. The pipeline is legible, but only once the reviewable interval is separated from the years that precede it.