FDOT Standard Plans · FY 2026-27 · Series 425: Structures
FDOT Standard Plans Index 425-070: Skimmer for Outlet Control Structures
Short answer
Index 425-070 is the FDOT Standard Plan for Skimmer for Outlet Control Structures, 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) FDM 308 ; Drainage Manual (DM) ; Structures Design Guidelines (SDG)
Design Assumptions and Limitations
Design Assumptions and Limitations This skimmer is intended for use on Type C, D, or E Ditch Bottom Inlets that are used as outlet control structures of stormwater management facilities. To minimize hydraulic losses across the skimmer, the flow area under the skimmer should be three times larger than the flow area of the weir slot. Provide a distance between the pond bottom at the structure and the skimmer of not less than 1 foot.
The configuration of skimmers may be subject to regulatory requirements. Coordinate the outlet control structure details with the permitting agencies. Modified structures must be designed in accordance with the requirements of SDG 3.17 .
Payment
Payment Item number Item Description Unit Measure 425-1-529 INLETS, DT BOT, (Type C), MODIFY EA 425-1-549 INLETS, DT BOT, (Type D), MODIFY EA 425-1-559 INLETS, DT BOT, (Type E), MODIFY EA 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.
- Summary Boxes: Summarize quantity by location in the Summary of Drainage Structures summary box, see BOE , Chapter
- - 070 Skimmer for Outlet Control Structures be reviewed in accordance with the Structures Manual, Volume 4
- - Fiber Reinforced Polymer Guidelines ( FRPG ).
How PDFDepth uses this index
When a plan set cites Index 425-070, 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.