Opinion for the Court filed by Circuit Judge SILBERMAN.
Aрpellees challenged the Federal Highway Administration’s approval of plans to replace the Woodrow Wilson Memorial *864 Bridge. The district court held that the Administration violated the National Environmental Policy Act and the National Historic Preservation Act. We reverse.
I.
The Woodrow Wilson Memorial Bridge is a microcosm of the Washington, D.C. metropolitan area’s traffic congestion problems. Built in 1961, the six-lane structure carries the Capital Beltway over the Potomac River, connecting the City of Alexandria, Virginia, to Prince George’s County, Maryland; originally intended to serve as a Washington bypass for interstate travelers, it became increasingly used by commuters as the region’s population grew. As a result, traffic volume on the Bridge has increased to over 160,000 vehicles per day, more than twice the cаpacity the structure was designed to accommodate; congestion is particularly acute during peak hours, where the configuration of an eight-lane Beltway feeding into a six-lane bridge — in addition to steadily increasing local traffic in the surrounding communities — has produced one of the worst rush-hour “bottlenecks” in the region. These congestion problems have created harmful collateral consequences: the heavy volume on the Bridge has contributed to an accident rate nearly double that of similar facilities in the region, and has expedited the deterioration of the Bridge’s structure to the point where the Bridge is projected to be structurally unsound by 2004.
Efforts to replace the Bridge began over ten years ago, when the Federal Highway Administration, in cooperation with its coordinate agencies in Maryland, Virginia, and the District of Columbia, began examining alternative approaches to solving the Bridge’s capacity and structural problems. The Administration began to study the potential effects of rebuilding the Bridge on the surrounding communities early in the project’s development, commissioning surveys of historic and archaeological resources in areas likely to be affected by the projects. The Commission also started the process, mandated by the National Environmental Policy Act (NEPA), 42 U.S.C. § 4321 et seq. (1994), of considering the environmental impacts of alternative project designs. In 1991 the Administration issued a draft Environmental Impact Statement (EIS) for public comment; this statement suggested and compared five proposals for replacing the Bridge. Each of the alternatives in the draft proposed expanding the rivеr crossing from six to twelve lanes, and included a similar expansion of the five-mile Beltway corridor approaching the river crossing from the east and west. 1
Reaction to the draft was less than enthusiastic; the Administration was criticized for assessing inadequately the environmental and cultural impacts of its proposal, and for failing to coordinate its work with that of interested governmental agencies and community groups. By its own admission concerned that “a region-wide consensus about the new bridge had not been reached,” the Administration went back to the drawing board. In response the Administration organized a “Coordination Committee” composed of elected and administrative officials from the region to enhance community and intergovernmental cooperation. The Committee revisited the entire prоcess of developing alternative Bridge designs, ultimately soliciting and considering over 350 proposals from interested individuals and organizations, and increased the Administration’s public outreach efforts in affected communities. In the meantime, pursuant to its obligations under section 106 of the National Historic Preservation Act, 16 U.S.C. § 470f (1995 & Supp.), and section 4(f) of the Department of Transportation Act, 49 U.S.C. § 303 (1997), the Administration continued to assess the project’s potential *865 impacts on historic, archaeological, and cultural resources in the area.
In 1997, the Administration issued its Final Environmental Impact Statement (the “Final EIS”). The Final EIS gave detailed consideration to eight alternative proposals (seven “build” alternatives and a baseline “no build” alternative), comparing them on a range of criteria including vehicle capacity, cost, and extent of environmental impacts. As was the case with the draft each of the “build” alternatives scrutinized in the Final EIS had twelve lanes; each alternative also had a lane configuration that separated local and express traffic, and contained a lane dedicated for High Occupancy Vehicle usage. The critical difference among the proposed alternatives was the type of river crossing; the seven “build” alternatives included a range of tunnel and bridge designs. Although the Final EIS discussed narrower eight- and ten-lane options, it did not afford them full treatment as formal “alternatives” because the Administration concluded, on the basis of traffic projections, that narrower river crossings would fall short of meeting the Bridge’s long-term traffic needs. Among the eight options the Administration designated a “Preferred Alternative” that would replace the Bridge with two parallel six-lane drawbridges (one drawbridge for eastbound and one for westbound traffic) clearing the Potomac’s navigational channel by seventy feet at their highest points. The Administration also included in the Final EIS a sixty-page “Section 4(f) Evaluation” identifying and offering plans to mitigate the effects of the Preferred Alternative and all other build alternatives on public parks, wildlife refuges, and historic sites.
After a brief comment period the Administration approved the Preferred Alternative in a Record of Decision and submitted, as is required by section 106 of the National Historic Preservation Act, a Memorandum of Agreement evidencing the Administration’s cooperation with state historic preservation officers in identifying historic sites that might be impacted. The Memorandum idеntified and offered mitigation plans for several historic sites, but it also noted that the Administration had not yet identified properties to be used for “construction staging, dredge disposal, wetland mitigation, or other ancillary activities” during the period of the Bridge’s construction.
The City of Alexandria filed an action in the district court challenging the Administration’s approval of the project, and the district court permitted three Alexandria-based organizations that opposed the Administration’s proposed alternative (collectively the “Alexandria Coalition” or “appel-lees”) to intervene as plaintiffs. The City alleged that the Administration had violated a host of regulatory provisions, including the National Environmental Policy Act, section 106 of the National Historic Preservation Act, and section 4(f) of the Department оf Transportation Act. 2 After both sides had filed for summary judgment the City of Alexandria settled its claim with the Administration, leaving the Alexandria Coalition as the only remaining plaintiffs.
The district court ruled in favor of the Alexandria Coalition.
See City of Alexandria v. Slater,
II.
A.
The National Environmental Policy Act’s mandate “is essentially procedural,”
Vermont Yankee Nuclear Power Corp. v. Natural Resources Defense Council, Inc.,
Appellees argue, and the district court agreed, that the Administration violated NEPA by failing to deem a ten-lane bridge a “reasonable alternative”. in the Final EIS. They observe that a ten-lane bridge would constitute a significant improvement over the existing six-lane structure, and would reduce congestion with considerably less impact on environmental and cultural resources than each of the twelve-lane alternatives compared by the Administration. In addition to having a narrower river crossing, appellees point out that a ten-lane alternative would have a smaller construction “footprint” along the entire five-mile stretch of the Beltway that will be under construction, and would require smaller interchanges at each of the four points of access to the Beltway in the project corridor. The Administration responds that the ten-lane alternative favored by appellees was excluded after studies determined that it did not meet the traffic capacity needs of the project. The Administration also argues that the difference between the environmental impacts of the two projects is less than appellees suggest; a ten-lane bridge would impact only 1.6 fewer acres of parkland and 12.9 fewer acres of natural resources over the entire length of the project corridor, and *867 would have an identical impact on cultural resources.
How are the merits of appellees’ argument to be assessed? After all, the phrase “reasonаble alternative,” standing alone, offers no guidance to a reviewing court. Something can only be an “alternative” by reference to something else; “the term ‘alternatives’ is not self-defining.”
Vermont Yankee,
We have resolved this difficulty by evaluating an agency’s choice of “reasonable alternatives” in light of the objectives of the federal action; as then-judge Thomas put it in Citizens Against Burlington, “[t]he goals of an action delimit the universe of the action’s reasonable alternatives.” Id. But that approach of course requires that we first consider whether the agency has reasonably identified and defined its objectives. The agency’s choice of alternatives are, then, evaluated in light of these stated objectives; an alternative is properly excluded from consideration in an environmental impact statement only if it would be reasonable for the agency to conclude that the alternаtive does not “bring about the ends of the federal action.” Id. We engage in both of these inquiries — whether an agency’s objectives are reasonable, and whether a particular alternative is reasonable in light of these objectives — with considerable deference to the agency’s expertise and policy-making role. Id. at 196.
The district court’s opinion suggests that the Administration improperly defined its objectives, criticizing the Administration for narrowing its choice of alternatives “based on a set of criteria that focused primarily on transportation and safety issues.”
City of Alexandria,
More in keeping with our precedent, the district court also determined that a ten-lane alternative was reasonable — and therefore should have been given greater attention — in light of these objectives. The district court arrived at this conclusion by characterizing the Administration as “articulat[ing] the problem as one of addressing the future transportation needs of the rеgion.” “Such a broad statement of purpose and need,” the district court explained, “hardly provides an unequivocal basis for eliminating ten-lane alternatives from consideration.”
City of Alexandria,
The district court ignored this data, instead focusing exclusively on an Administration study showing that a ten-lane bridge would be able to accommodate up to 295,000 vehicles per day, a number only slightly smaller than the projected daily traffic flow on the Bridge in 2020.
City of Alexandria,
Appellees’ more fundamental argument is that, regardless of its shortcomings in satisfying future traffic needs, we must hold a ten-lane bridge to be a reasonable alternative in light of our statement in
Natural Resources Defense Council, Inc. v. Morton
that an agency should not “disregard alternatives merely because they do not offer a complete solution to the problem.”
*869 Morton thus stands for the same proposition as Citizens Against Burlington: namely, that a “reasonable alternative” is defined by reference to a project’s objectives. Morton explained that, within the context of a coordinated effort to solve a problem of national scope, a solution that lies outside of an agency’s jurisdiction might be a “reasonable alternative”; so might an alternative within that agency’s jurisdiction that solves only a portion of the problem, given that other agencies might be able to provide the remainder of the solution. Such a holistic definition of “reasonable alternatives” would, however, make little sense for a discrete project within the jurisdiction of one federal agency, as we recognized in Morton when we contrasted the Secretary’s action with that of building “a single canal or dam.” 4 Id. Concerned with severe traffic conditions in the Capital Region, Congress has authorized the Administration to replace the Woodrow Wilson Memorial Bridge. The Administration has sole responsibility for solving this problem; were it to build a ten-lane bridge, no one else would step in and аlleviate the congestion that would result. 5 In this context, it is simply a non sequitur to call a proposal that does not “offer a complete solution to the problem” a “reasonable alternative.”
One other point merits brief discussion. In finding a ten-lane alternative reasonable, the district court noted that the Administration only conducted a Clean Air Act conformity analysis for the use of ten lanes on the Bridge.
See City of Alexandria,
B.
Once an agency identifies the “reasonable alternatives” to a proposed action, NEPA and Council on Environmental Quality regulations also require an agency to identify the “adverse environmental effects” of each alternative. See 42 U.S.C. § 4332(2)(C)(ii); 40 C.F.R. § 1502.16. The district court found fault with the Administration’s treatment of the temporary “construction impacts” that would arise during the period that the Bridge was being built. Again, we disagree.
The district court focused on the brevity of the “Construction Impacts” section of
*870
the Final EIS, which covers only four pages and, according to the district court, “is of such a broad and generic naturе that it could apply to practically any construction project undertaken by the [Administration].”
City of Alexandria,
We think the terseness of the Administration’s discussion of construction impacts is justified for other reasons as well. The Administration typically delays the identification of “construction staging” sites— locations used to store materials and equipment during project construction— until the design stage of the project. As will be discussed infra, this practice is permissible under the statute and is arguably required by the Administration’s governing regulations. Since the Administration did not identify the location of these areas, it of course could not identify the accompanying environmental impacts with precision. But this does not mean that the Administration did not consider, on a more general level, what those impacts would be; the Final EIS identifies several potential staging areas, and notes that each of these sites are in “previously disturbed” areas with “minimal natural resources.” The Administration’s brevity is particularly understandable given the numerous regulatory constraints that will limit the extent of construction activities. As the Administration notes, Maryland and Virginia require construction contractors to limit noise levels in “noise sensitive areas adjacent to the project area” to eighty decibels — a noise level comparable to that currently produced by traffic on some stretches of the highway. Similar federal and state regulatory provisions require the mitigation of any short-term construction impacts on wetland and aquatic resources, constrain the emissions of dust from construction-related activities and equipment, and limit the Administration’s selection of construction staging areas. The Final EIS’ reference of these provisions is important, as it indicates the Administration’s awareness of the maximum impact that the construction may cause.
We also note that agencies are enjoined by the Council on Economic Quality to develop environmental impact statements that are “no longer than absolutely necessary” and that discuss impacts “in proportion to their significance.” 40 C.F.R.
*871
§ 1502.2(b)-(c). The Administration points out that each of the seven “build” alternatives would have similar construction impacts, thus making a detailed discussion of each of their effects redundant. More fundamentally, while the disruption caused by the construction of a project as significant as this, one is by no means trivial, it is relatively modest in both scope and duration when compared to the environmental impact of the prоject as a whole. To be sure, there is a point at which an agency’s analysis ventures from the “tolerably terse to the intolerably mute,”
Greater Boston Television Corp. v. FCC,
III.
A.
The district court concluded that the Administration also failed to identify adequately the effect that its preferred alternative will have on historic resources in the project area, as is required under two distinct but overlapping statutes: section 106 of the National Historic Preservation Act and section 4(f) of the Department of Transportation Act. Section 106, like NEPA, is essentially a procedural statute; it requires that agencies “take into account the effect of [an] undertaking on any district, site, building, structure, or object that is included in or eligible for inclusion in the National Register [of Historic Places].” 16 U.S.C. § 470f. To comply with section 106, an agency must consult with state historic preservation officers to ensure that historic properties in the project area are thoroughly identified and the effects that the project will have on them fully assessed. See 36 C.F.R. § 800.4-.5. 6 The usual product of this consultation process is a Memorandum of Agreement among the consulting parties signifying agreement upon how the detrimental effects will be “taken into account.” Even where disagreement precludes the completion of a Memorandum of Agreement an agency may implement a project after receiving and considering comments from the Advisory Council on Historic Preservation. See id. at 800.6(c).
On the other hand, section 4(f), unlike the other statutes at issue in this case, imposes a substantive mandate on the Administration: It prohibits the agency from taking an action that “uses” a historic resource unless there is “no prudent and feasible alternative to using that land” and the agency engages in “all possible planning” to “minimize harm” to the sites.
7
49 U.S.C. § 303(c);
see also Citizens to Preserve Overton Park v. Volpe,
The central dispute between the parties is not about whether, but about when, the Administration must complete its identifi *872 cation of historic properties. The Administration has been “taking into account” the effect of the proposed project on historic sites since the project’s inception, conducting several surveys which led to the identification of 23 National Register-listed or National Register-eligible properties, and 36 underwater or terrestrial archaeological .sites in the project area. The Administration also identified and visited each National Register-listed property in Alexandria for the purpose of determining, among other things, the “visual impacts” that various alternative bridge proposals would have on each site. The result was publication of a Memorandum of Agreement and a Section 4(f) Evaluation with or prior to the Administration’s approval of the project; these documents identify seven historic sites that will be affected by the project and another six that may be, and offers plans to minimize and mitigate the project’s impact on these properties.
The district court did not question the overall legitimacy or thoroughness of these studies.
8
(Indeed,.appellees cannot identify a single historic resource in the project area that the Administration failed to “take into account.”
9
) Instead, the district court concluded that the Administration violated section 106 by deciding to postpone the identification of sites where it would conduct certain construction-related activities, including construction staging areas (the locations where contractors will store materials and mobilize construction activities), wetland mitigation areas, and dredge disposal sites. While the likely impact of these activities, which the Administration describes as “ancillary,” are minimal when compared to those, of the project as a whole, it is at least conceivable that they could ultimately affect section 106 properties. Acknowledging this possibility, but noting that it usually defers the identification of such properties until the “design stage” of a large highway project, the Administration included promissory language in its Memorandum of Agreement binding it to fulfill its section 106 responsibilities when selecting these sites. The district court thought that these prospective terms ran afoul of our recent decision in
Corridor H Alternatives, Inc. v. Slater,
We think that district court misconstrued our holding in
Corridor H.
In that case, the Administration postponed the entire section 106 process for a major highway corridor; its Record of Decision instead adopted a “Programmatic Agree
*873
ment” dividing the highway into fourteen segments, and promised that it would not begin construction of a particular segment before completing the section 106 process for that segment. We held that this Agreement impermissibly abrogated the Administration’s responsibility to assess the project’s impact on historic properties during the planning stages of the project.
See
The Administration did not postpone the identification of these properties “merely to avoid having to complete its 4(f) and 106 analyses,” as the district court said.
B.
We also think that the Administration satisfied section 4(f)’s substantive provisions. Appellees barely bother to argue that the Administration did not comply with section 4(f)(1)’s requirement that it consider all “prudent and feasible alternative[s]” to using protected properties. The reason for this gap in appellees’ otherwise vigorous presentation is obvious enough. For while the Administration is required to give the protection of 4(f) property “paramount importance” in determining whether an alternative is “prudent,”
Overton Park,
Appellees do argue with greater enthusiasm that the Administration, violated section 4(f)(2)’s requirement that the agency engage in “all possible planning” to minimize harm to 4(f) properties, but this argument is equally unpersuasive. To begin at the broadest level of generality, appellees do not question the Administration’s express findings that, among the seven “prudent and feasible” alternatives compared in the Final EIS, the preferred alternative
*874
“results in the least overall impact to section 4(f) resources.”
Cf. Druid Hills Civic Ass’n, Inc. v. FHWA,
* * *
During the course of our consideration of this case, appellees have attempted to bolster their position by pointing to the opposition of prominent legislators to the project, and by noting the hurdles to ultimate congressional approval that still lie in the Administration’s path. These political impediments are irrelevant to us but they indicate where appellees should concentrate their efforts. We have been admonished by the Supreme Court with respect to the very statute that is at the heart of this case to avoid using its requirements as a vehicle to impose our own judgment.
Vermont Yankee,
So ordered.
Notes
. More specifically, the project would widen the Beltway to twelve lanes between Telegraph Road in Alexandria and Route 210 in Prince George’s County.
. The City also alleged that the Administration violated the Clean Air Act by failing to conduct a conformity analysis for the twelve-lane preferred alternative. The district court agreed, but the Administration does not appeal this finding.
. The Council on Environmental Quality has no express regulatory authority under the National Environmental Policy Act; instead, the Council was empowered to promulgate binding regulations by President Carter’s Executive Order No. 11991, 42 Fed.Reg. 26,967 (1977). Because the Administration does not challenge the Council’s regulatory authority, we treat the Council’s regulations as binding on the agency. But see Scott C. Whitney, The Role of the President’s Council on Environmental Quality in the 1990s and Beyond, 6 J. Envtl. L. & Lit. 81 (1991).
. We doubt the continuing vitality of the rather expansive view of NEPA we expressed in
Morton,
since subsequent Supreme Court cases have directly criticized us for overreading that statute's mandate.
See Baltimore Gas & Elec. Co.,
. As the Administration determined, there are no appаrent and feasible independent rail transit options that could be combined to a ten-lane bridge to. satisfy transportation needs.
. The Council has recently promulgated regulations revising the section 106 process. 64 Fed.Reg. 27,044 (1999). Our citations are to the regulations as they existed at the time the Administration approved the project.
. In addition to historical sites, other properties — including parks, recreational areas, and wildlife preserves — are protected by section 4(f).
. Appellees point to the Administration’s decision to reduce the size of the "Area of Potential Effects” in 1997, and suggest that the Administration reduced this Area in an attempt to evade section 106's obligations. The Administration offers a perfectly innocent explanation, which we have no reason to question: The Area of Potential Effects was originally drawn with a range of alternatives in mind, including taller bridge designs with far more extensive "visual effects” in Alexandria. It was then reduced to encompass only those areas affected by the preferred alternative. Notably, appellees do not point to any properties outside of the new "reduced” Area of Potential Effects that will actually be affected by the project.
. Amicus Sierra Club rather inventively argues that the Administration failed to treat as a section 106/4(1) property the Hunting Terrace apartment complex in Alexandria, but it is not eligible for inclusion in the National Register of Historic Places, and therefore is not a protected property under either section 106 or section 4(f).
See
23 C.F.R. § 771.135(e); 36 C.F.R. § 800.2(e). Showing similar ingenuity, appellees argue that the Administration violated sections 106 and 4(0 beсause "the boundaries of Freedman's Cemetery ... have still not yet been determined.” They apparently believe that since the site’s precise location is unknown (and, it seems, unknowable), it is by definition impossible to know for certain the "effect” that the construction will have on the site, thus placing the Administration in violation of sections 106 and 4(f). To set forth the logic of this argument is to refute it.
Cf. Hoonah Indian Ass’n v. Morrison,
. Appellees correctly note that section 4(f)’s substantive requirements can only be complied with after section 4(f) properties have been identified. We remind the Administration that our holding that it could defer the identification of section 4(f) properties that might be impacted by construction staging and dredge disposal activities in no way absolves it of its responsibility to conduct a 4(1) analysis when selecting these sites during the design stage of the project.
