FDOT Standard Plans · FY 2026-27 · Series 425: Structures
FDOT Standard Plans Index 425-051: Ditch Bottom Inlet Type B
Short answer
Index 425-051 is the FDOT Standard Plan for Ditch Bottom Inlet Type B, part of Series 425 (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 and Guidance FDOT Design Manual (FDM) ; Drainage Manual (DM) ; Drainage Design Guide (DDG)
Design Assumptions and Limitations
Design Assumptions and Limitations The general purpose of the inlet top designs are: a. For ditches, medians or other areas subject to traffic loads. This inlet may be placed in areas subject to occasional pedestrian traffic such as landscaped areas and pavement areas where pedestrians can walk around the inlet.
Inlet is not suitable for bicycle traffic. b. Provide full grate and horizontal slot designs for new construction.
c. Provide full grate and horizontal slot designs for replacing the vertical slot tops on existing Inlets Type B and Type X that are in locations subject to occasional pedestrian traffic. Recommended maximum pipe sizes for concrete pipe: For 3’8” Inlet Inside Width: 30” For 4’2” Inlet Inside Width: 36” Sizes for other types of pipe must be checked for fit in accordance with Index 425-001 .
For larger pipe see bottom detail in Index 425-010 .
Payment
Payment Item number Item Description Unit Measure 425-151- Inlets, DT Bot, Type B EA 520-1- Performance Turf SY See the BOE and Specification 425 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.
- - 051 Ditch Bottom Inlet Type B
How PDFDepth uses this index
When a plan set cites Index 425-051, 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 425
- Index 425-001 — Manhole Covers, Frames, Tops, and Supplementary Inlet Details
- Index 425-010 — Structure Bottoms Type J and P
- Index 425-020 — Curb Inlets Types 1-10
- Index 425-021 — Curb Inlet Top Types 5 and 6
- Index 425-022 — Curb Inlet Type 7
- Index 425-023 — Curb Inlet Type 8
- Index 425-024 — Curb Inlet Type 9
- Index 425-025 — Curb Inlet Type 10
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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.