FDOT Standard Plans · FY 2026-27 · Series 436: Structures
FDOT Standard Plans Index 436-001: Trench Drain
Short answer
Index 436-001 is the FDOT Standard Plan for Trench Drain, part of Series 436 (Structures). The sections below are extracted from FDOT's Standard Plans Instructions (SPI) for this index — design criteria, assumptions and limitations, and what your plans must show.
Design Criteria
Design Criteria FDOT Design Manual (FDM) ; Drainage Manual (DM)
Design Assumptions and Limitations
Design Assumptions and Limitations Trench drain is intended for use in gutters and driveways as shown on the typical locations on Sheet 2. Type I is intended for use in Type E, F, and drop curbing, and adjacent to traffic separators and standard barrier walls. The width of the channel grate for Type I Trench Drain should be 1 ¾” throughout varying the depth of the channel neck.
Type II may also be used in those locations if an independent laboratory certifies that the grating used has an open area equal to at least 0.27 square feet per linear foot. Type II is primarily intended for use in valley gutter across driveway openings and drop curbing; Type I may also be used in those locations. The width of the channel grate for Type II Trench Drain shall be the same as the width of the channel.
The linear slope or gradient for Type II may be manufactured by varying the depth of the channel. Do not place Trench Drain in pedestrian paths unless ADA compliant grates are used. For trench drains placed adjacent to reinforced concrete barrier, include details in the plans showing the position of the drain relative to the barrier to avoid conflicts with the foundation.
See Index 521-001 . Capture efficiency for Type I Trench Drain may be calculated using the equations for slotted drain in FHWA’s HEC 12 and 22. Grate Type I and II must have at least 30% open area.
Round pipe alternate is available in 12, 18, 24, and 36 inch. Type II Preformed Channel with integral anchoring lugs are applicable.
Payment
Payment Item number Item Description Unit Measure 436 - 1- A Trench Drain LF See the BOE and Specification 436 for additional information on payment, pay item use and compensation.
What your plans must show
Plan Content Requirements for this index — the SPI's checklist for designers.
- Plan requirements can be found in the Drainage Manual (DM) Section 3.9.2.
How PDFDepth uses this index
When a plan set cites Index 436-001, PDFDepth's AI Plan Review cross-references the set against the Plan Content Requirements for the FDOT indexes it cites and flags items that appear to be missing — each with a citation to the sheet. A human reviewer verifies every flag before it counts.
Related indexes in Series 436
- Index 440-001 — Underdrain Inspection Box
- Index 440-002 — Underdrain Inspection Box
- Index 443-001 — Skimmers for French Drain Outlets
- Index 443-002 — Skimmers for French Drain Outlets
- Index 446-001 — Concrete Pavement Subdrainage
- Index 450-010 — Series Prestressed Florida - I Beams
- Index 450-036 — Index 450-036
- Index 450-045 — Index 450-045
Try it yourself — open your plan set in PDFDepth
Review, measure, and check plan sets against the standards they cite — free for 14 days.
Start for FreeText extracted from FDOT Standard Plans FY 2026-27, a public-domain Florida state publication. Always verify against the current edition at fdot.gov. PDFDepth is not affiliated with FDOT.