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U.S. Department of Transportation
Federal Highway Administration
5520.1
December 24, 1990
Par.
Purpose
Superseded Issuance
Authority
Scope
Policy
Definitions
Procedures
PURPOSE. To prescribe policy and procedures for preliminary plan submissions and approvals for bridges, tunnels, geotechnical features, and hydraulic structures.
SUPERSEDED ISSUANCE. Federal Highway Administration (FHWA) Federal-aid Highway Program Manual (FHPM) Volume 6, Chapter 1, Section 2, Subsection 1 dated October 16, 1975, is superseded by this Order and will be canceled by an FHPM Transmittal.
AUTHORITY. This Order is issued under the authority of 23 U.S.C. 109(a), 117, 135; 23 CFR 1.32; 49 CFR 1.48(b)(8); Executive Order 11988 dated May 24, 1977, (42 FR 26951); and FHWA Order M1100.1, FHWA Delegations and Organization Manual, Chapter 5, paragraph 34j.
SCOPE. The provisions of this Order shall apply to all highway projects constructed with Federal-aid funds and projects under the direct supervision of the FHWA.
POLICY. It is the policy of the FHWA that preliminary plans shall be submitted to the FHWA for review and approval as follows:
Washington Headquarters shall approve all tunnels, unusual and movable bridges, unusual hydraulic structures and unusual geotechnical structures.
Regional Federal Highway Administrators shall approve all other bridges not included in paragraph 5a which have estimated total deck areas greater than 125,000 square feet, major hydraulic structures and major geotechnical features.
When FHWA bridge, hydraulic or geotechnical engineers in a particular region have substantial recent experience with a particular design, review and approval authority for the preliminary plans may, upon agreement between the Regional Administrator and the Chief of the FHWA Bridge Division, be delegated to the Regional Administrator. Any request for waiver of alternate design requirements (as described in the June 9, 1988, Federal Register) shall be transmitted through organiza- tional channels to the Washington Headquarters for review and approval.
DEFINITIONS
Unusual bridge, hydraulic or geotechnical structures include any of the following:
(1) An unusual bridge involves difficult or unique foundation problems, new foundation types, new or complex designs involving unique design or operational features, longer than normal spans or bridges for which the design procedures depart from current acceptable practice. Examples include cable stayed, suspension, arch, segmental concrete bridges, trusses and other bridges which deviate from AASHTO Standard Specifications or Guide Specifications for Highway Bridges, bridges requiring abnormal dynamic analysis for seismic design, bridges designed using a three-dimensional computer analysis, bridges with spans exceeding 500 feet, and bridges which include ultra high strength concrete or steel.
(2) An unusual geotechnical feature involves new or complex retaining wall systems or ground improvement systems.
(3) An unusual hydraulic structure involves unusual stream stability countermeasures, an atypical or unique design technique; or a complex or unique design which may include hydraulic structures covered in paragraph 6b.
Major hydraulic structures include but are not limited to:
(1) storm drainage systems designed to carry more than 200 cfs or, regardless of quantity of discharge, which have a surface detention storage system with an accumulated volume greater than five-acre feet,
(2) storm water pumping facilities designed to discharge more than 20 cfs,
(3) dams formed by highway fills which will affect permanent impoundment of water more than 25 feet deep or 50 acre-feet in volume; and,
(4) stream levees formed by highway fills which are constructed along a stream or body of water to reduce flooding in adjacent areas.
Major geotechnical features include unusually deep cuts or high fills where the site geology is potentially unstable, landslide corrections, and large retaining walls (cantilever, permanent ground anchor, and soil reinforcement). (See Table 1, Section A of FHWA's October 25, 1985, "Checklist and Guidelines for Review of Geotechnical Reports and Preliminary Plans and Specifications," for additional guidance.)
Uncertainties as to whether a project fits these definitions shall be referred to the Regional Administrator for resolution.
PROCEDURES
Preliminary plans and supporting data for structuresdescribed in paragraph 5a shall be reviewed by the Division Administrator and submitted to the Washington Headquarters through the regional office with review comments and recommendations for approval as appropriate.
Supporting information submitted with the initial request for review and approval shall include environmental concerns and suggested mitigation measures, studies of alternate span arrangements and bridge types, approach layouts, plan and profile sheets, controlling clearance requirements, roadway geometry, design specifications, design criteria, special provisions and construction cost estimates. Supporting data should also include hydraulic and scour design studies and reports including scour prediction and mitigation measures, geotechnical reports and studies and substructure and foundation type. Early and complete submission of hydraulic and geotechnical studies and recommendations is essential to expedite approval.
Preliminary plans and supporting data for structures described in paragraph 5b shall be reviewed by the Division Administrator and submitted to the Regional Administrator with review comments and recommendations for approval.
(1) Supporting data shall include information as listed in paragraph 7b, and in the case of dams and levees, evidence of coordination with the State or Federal agency responsible for the safety of dams within the State.
(2) The Regional Administrator may seek Washington Headquarters advice and guidance before taking approval action.
