Section 1680-09-01-.04 - STANDARDS(1) Railroad Track and Crossing Pad Standards.(a) The crossing pad shall be constructed of any paved or panelized crossing surface material compatible with the current practices of the involved railroad, or of such material as the Department may require.(b) Specifications and plans concerning the crossing surface material and use shall comply with the manufacturer's recommendations and the involved railroad's current standards and specifications.(c) The width of the crossing pad at the grade crossing shall correspond to the width of the approach roadway cross section, including but not limited to the traffic lanes and any shoulders, pedestrian walkways and bicycle paths; provided, however, that the crossing pad shall have a minimum width of 32 feet.(d) The crossing pad shall have the same number and width of traffic lanes and shoulders as the approach roadway.(e) Roadway markings shall be provided on the crossing pad in accordance with the MUTCD.(f) Flangeways of not less than 21/2 inches nor more than 3 inches in width shall be provided between the rail and the crossing pad, except where track geometry or other track appliances may require otherwise. Flangeways shall be at least 2 inches in depth, except as the involved railroad may otherwise approve.(g) Materials and specifications shall comply, at a minimum, with the following:1. Materials. All track materials used - including but not limited to ties, crossing pads, fasteners, geotextile fabric, drainage tile and other track material - shall be new, except that rail may be No. 1 relay or new.
2. Drainage. Adequate engineered drainage shall be provided. The drainage design for cross-drainage and trackside shall be based on a 50-year design frequency, checked for 100-year, or on the current design frequency standards of the involved railroad.
3. Ballast. The ballast and sub-ballast shall be dug out and replaced to a minimum of 10 inches below the bottoms of the ties, a minimum of 2 feet beyond the ends of the ties, and a minimum of 20 feet beyond the end of the crossing pad.
4. Ties. (i) Where a crossing system requires the use of track ties, the ties shall be made of preservative-treated No. 5 air-dried hardwood of not less than 9 inches wide and not less than 7 inches deep, or the ties shall be made of concrete, steel, plastic or other materials of suitable strength and dimensions, consistent with the standards of the involved railroad. The ties shall be installed through the limits of the crossing and beyond the crossing pad a minimum of 20 feet. The length and spacing of the ties shall conform to the type of grade crossing surface materials being used.(ii) Where the crossing system design does not require track ties, the crossing system shall be adequate to maintain track gage, surface and alignment as defined by applicable FRA regulations.5. Rail.(i) Rail size of 112 pounds per yard, or the current size of rail used on the line, whichever is larger, shall be used through the limits of the crossing and beyond the crossing pad a minimum of 20 feet.(ii) The rails throughout the crossing shall be installed to eliminate joints within the crossing. The nearest joint shall be not less than 20 feet from the end of the crossing pad. Where necessary, long rails shall be used or the rail ends shall be welded to form continuous rail through the crossing; provided, however, that no welded rail of greater than 400 feet in length shall be used without the approval of the involved railroad.(iii) Any compromise joints (joints involving two different rail sizes) created by this crossing installation shall be welded or use transition rails or compromise rail joint bars of the proper size.(iv) Torch cutting of rail ends or boltholes is prohibited.6. Rail fasteners, plates and anchors. Each tie system shall use the appropriate fastener and anchor systems to maintain gage and limit longitudinal rail movement. Where ties with spikes are used, they shall be fully tie-plated with a minimum of four spikes per tie plate, and they shall be fully box anchored, as allowed by the crossing surface material, through the crossing area and at least 20 feet beyond each end of the crossing pad. Where other systems are used, each tie must be fully attached to both rails in accordance with the system being used.
(h) Railroad alignment design. Where grade crossings have two or more tracks, the tops of the rails for all tracks shall be brought to the same plane, where practical. All surface geometry design shall be in full compliance with applicable FRA regulations and railroad standards.
(i) Lining and surfacing track. Rails shall be spiked or fastened to line and the track machined or mechanically tamped and surfaced to the grade and alignment of the existing track and roadway. In order to achieve the optimum ballast compaction through the crossing area, lining and surfacing shall involve two passes at a minimum, allowing as many train movements as time will permit, across the grade crossing before final surface and alignment.
(2) Roadway Standards. (a) Roadway alignment design. 1. Vertical alignment. (i) The surface of the roadway shall be in the same plane as the tops of the rails for a distance of at least 2 feet beyond the rails for either single or multiple-track crossings.(ii) The top of the rail plane shall be connected with the grade line of the roadway each way by vertical curves of such length as is required to provide riding conditions and sight distances normally applied to the roadway involved.(iii) Unless track superelevation dictates otherwise, the vertical alignment of the roadway shall comply with the current recommended practices stated in the AASHTO Design Manual.2. Roadway surface cross slope. (i) Roadway surface cross slope should be eliminated within 10 feet of the rail at the grade crossing to ensure a proper meet between the roadway and crossing pad surfaces.(ii) Pavement transition lengths should be in accordance with TDOT Standard Roadway Drawings and the AASHTO Design Manual.(iii) The engineer shall ensure that elimination of the roadway surface cross slope does not cause ponding.(iv) Any proposed exceptions based on roadway curvature, superelevation, or other design considerations must be approved by the Department.3. Horizontal alignment. The roadway shall be designed to provide no less than a 75-degree approach at the grade crossing, and, if practical, the roadway should be designed to intersect with the railroad track or tracks at a right angle or as near to a right angle as possible. Any proposed exception must be based on an engineering study and approved by the Department. Railroad curves should be avoided when practical.
(b) Roadway surface. 1. Materials and placement. The roadway shall be paved, at a minimum, within 150 feet of the nearest rail at the grade crossing. The depth and type of the pavement material used, and the placement of the base and pavement, shall comply with all requirements for base and pavement stated in the TDOT Standard Specifications for Road and Bridge Construction.
2. Roadway and lane width. The width of the roadway at the grade crossing shall correspond to the width of the approach roadway, including traffic lanes and shoulders. The roadway at the grade crossing shall have the same number and width of traffic lanes and shoulders as the approach roadway. In the event that the approach roadway is less than 32 feet wide, a minimum paved approach of 32 feet shall be provided within 25 feet of the nearest rail at the grade crossing, with lane widths remaining the same as on the approach roadway.
3. Roadway markings. At all paved approaches to the grade crossing, the roadway shall be marked in accordance with the MUTCD.
(c) Drainage. 1. Adequate engineered drainage shall be provided.2. The following design frequencies based on roadway classification shall be used for drainage design: | (i) | Culvert design frequency: | |
| Multi-lane divided roadway: | 50-yr.; check 100-yr. |
| Arterial and collector: | 50-yr.; check 100-yr. |
| Local road: | 50-yr.; check 100-yr. |
| (ii) | Ditch design frequency: | |
| Multi-lane divided roadway: | 50-yr. |
| Arterial and collector: | 10-yr.; 50 yr. in sags |
| Local roads: | 10-yr. |
| (iii) | Roadway freeboard: | |
| All roadways: | 50-yr. |
| (iv) | Inlet and sewer design frequency: | |
| Multi-lane divided roadway: | 50-yr. |
| Arterial and collector: | 10-yr.; 50-yr. in sags |
| Local roads: | 10-yr. |
3. The design frequency selected for cross drainage structures: (i) Shall not significantly increase the flood hazard for adjacent property; and(ii) Shall permit maintenance of vehicular traffic on roads and streets under design flood conditions.4. The design frequency for roadway storm drainage structure design:(i) Shall not significantly increase the flood hazard for adjacent property; and(ii) Shall limit the encroachment onto the traveled lanes that could cause a hazard to vehicular traffic.5. In situations where the grade of the approach roadway descends toward the grade crossing, provisions shall be made to intercept surface and subsurface drainage and discharge it laterally so that it will not be discharged onto the track area.(3) Signage Standards.(a) Railroad signs. 1. The railroad shall erect and maintain a whistling post or whistle board in each direction from the grade crossing along its track(s). The sign will serve to alert operating train crews to the upcoming crossing so that a whistle warning may be sounded. The location of the post or board shall comply with any applicable FRA regulations and railroad company standards or policies.2. The railroad shall install and maintain an emergency notification sign at each grade crossing in accordance with the MUTCD. At a minimum, this sign shall show the USDOT-AAR crossing inventory number, the milepost (if available), the roadway name, and the telephone number to call to report an emergency.(b) Roadway signing and marking.1. Passive warning devices shall be installed and maintained on the roadway at grade crossings in accordance with the MUTCD.2. When a grade crossing is located at or near a roadway-roadway intersection, signage shall be installed at the intersection in compliance with the MUTCD.(4) Standards for Active Warning Devices.(a) The Department may require the installation of active warning devices at a grade crossing in accordance with the following minimum criteria, or as the Department may determine after conducting a diagnostic team field review: | Type of Active Warning Device | Minimum Criteria |
| 1. Flashing-Light Signals (Post-Mounted) with Automatic Gates: | 3,000 or more exposures, or Inadequate sight distances, as determined in accordance with the AASHTO Design Manual, Or The roadway at the grade crossing is a designated school bus route, commercial passenger vehicle route, or hazardous material route, Or Two or more railroad tracks at the grade crossing that may allow concurrent rail operations, Or The presence of a signalized highway intersection within 200 feet of the grade crossing. |
| 2. Flashing-Light Signals (Overhead) with Automatic Gates: | Three or more lanes (including turning lanes) on the roadway at the grade crossing, Or 3,000 or more exposuresandinadequate sight distances, as determined in accordance with the AASHTO Design Manual. |
| 3. Flashing-Light Signals (Post-Mounted or Overhead as indicated above) with Automatic Four-Quadrant Gates and/or other safety devices as required by the Department: | 20,000 or more exposuresandthe presence of any passenger train traffic on the railroad. |
(b) All active warning devices required under this Rule shall be installed and maintained in accordance with the MUTCD.(c) Whenever a signalized grade crossing is to be located near a signalized highway intersection, preemption shall be provided for in compliance with the MUTCD.(d) Railroad Circuitry. In connection with the installation of active warning devices at a grade crossing, the following types of circuitry shall be installed and maintained on the railroad tracks in accordance with the criteria specified below:
| Type of Circuitry | Criteria |
| 1. Style C or AC/DC: | Infrequently used tracks. |
| 2. Motion Sensors: | On regularly or frequently used tracks, where there is considerable switching, trains stopped or parked near the grade crossing, or consistent train speed. |
| 3. Constant Warning Time: | On regularly or frequently used tracks with variable train speeds. |
(5) Grade Separation. (a) Grade separation shall be required, and no grade crossing will be approved, on any roadway/railroad crossing where there is full control of access on the roadway.(b) The department may also decline to approve the proposed construction or conversion of a grade crossing where: 1. A grade separation is feasible (based on topographic conditions, cost, and other relevant factors), and2. Special hazardous conditions exist, including but not limited to the presence of highspeed (75 mph or more) passenger train traffic on the railroad or where trains block the crossing for long periods of time.(6) Pedestrian Walkways and Bicycle Paths. (a) Where federal funds are to be used in paying for all or any part of the costs of installing the grade crossing, provisions for pedestrian walkways and bicycle paths should be considered.(b) Any pedestrian walkway or bicycle path included in the grade crossing shall comply with FRA track safety standards, 49 C.F.R., Part 213, or as amended, and the Americans' With Disabilities Act accessibility guidelines contained in 28 C.F.R., Part 36, Appendix A, or as amended.Tenn. Comp. R. & Regs. 1680-09-01-.04
Original rule filed April 5, 2002; effective June 19, 2002. Rule has been assigned a new control number from 1680-12-1-.04 filed and effective February 1, 2003.Authority: T.C.A. § 65-11-101.