Active Design Memos
Design Memos are typically published the second week of each month. Unless otherwise stated, associated revisions to the Indiana Design Manual (IDM) are published concurrently. Memos remain active for one year then are moved to the Archived Design Memos page. Superseded memos are archived immediately. Memos that include guidance that has not been incorporated into the IDM or other INDOT publication may remain active longer. Memos that are integral to applying a recurring special provision (RSP) or recurring plan detail (RPD) may remain active longer. The practice of distinguishing policy memos from techncial advisories was discontinued January 2018. This Page Last Updated 4/8/25 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 25-12 | 4/16/25 | Plan Revisions after Ready for Contracts | 14‐1.02(04), 14‐1.02(06), 14‐1.02(07), (new) Figures 14‐1 O, 14‐1P, and 14‐1Q | Immediately |
| 25-11 | 4/16/25 | Lean Concrete Base | 17‐5.09(02), 603‐3.01, and 604‐2.03 | Lettings on or after June 1, 2025 |
| 25-10 | 4/16/25 | Void Reducing Asphalt Membrane for Asphalt Paving | 602‐3.02 | Lettings on or after September 1, 2025 |
| 25-09 | 4/16/25 | Rewrite Chapter 43 Horizontal Alignment | Chapter 43 (all sections), Chapter 48, Sections 48‐4.01(06), 48‐5.03(01), and 48‐5.03(02) | Stage 2 Submittals on or after July 1, 2025 |
| 25-08 | 3/25/25 | Life-Cycle Pavement Cost Analysis Update | 602-2.0, 606-1.0, 606-2.05, 606-3.01, and 606-3.02 | Lettings on or after September 1, 2025 |
| 25-07 | 2/13/25 | Topsoil Management | 17-4.10, 17-4.10(01) 17-4.10(02), 17-4.10(03), and 17-4.10(09) [New] | Lettings on or after September 1, 2025 |
| 25-06 | 2/13/25 | Prestressing Strands | 406-10.0 and 406-12.02(03) | Lettings on or after September 1, 2025 |
| 25-05 | 2/13/25 | Reinforcing Bar Support Devices | Figures 405-3D and 405-3E, Section 406-12.03(03),and Figure 406-12D [New] | Lettings on or after September 1, 2025 |
| 25-04 | 2/13/25 | NEXT Beams | 406-12.02(01), Figures 406-14BB and406-14DD | Lettings on or after September 1, 2025 |
| 25-03 | 1/21/25 | Maintenance of Traffic Updates | 503-2.05(01), 503-6.01, 503-7.01(04), 503-7.03, and 503-7.05 | Lettings on or after September 1, 2025 |
| 25-02 | 1/21/25 | Various Traffic Design Updates | 502-1.01(06), 502-1.01(14), 502-1.02(09)[New], 502-3.06(07)[New], 502-4.03(05), 502-4.07, and Figure 502-1E | Lettings on or after September 1, 2025 |
| 25-01 | 1/21/25 | IHCP Exception Requests | NA | As Noted |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 24-17 | 12/04/24 | Liquid Asphalt Sealant | Figures 602‐3A thru 602-3D, 602-3G, 602-3H, and 602-3J | Immediately |
| 24-16 | 11/06/24 | MSE Wall Shop Drawing Review Checklist | N/A | Immediately |
| 24-15 | 11/06/24 | FHWA-Indiana PS&E Checklist | 14-2.01(13), 14-2.03(10), 14-2.04(09), 14-2.05(05), 14-2.06(03), 14-2.07(03), and 14-2.08(03) | Lettings on or after September 1, 2025 |
| 24-14 | 09/11/24 | Pavement Ledge Width | 405‐3F, 406‐16E, 406‐16L, 406‐16S, 409‐2D,and 409‐3D | Lettings on or after September 1, 2025 |
| 24-13 | 09/11/24 | Integral End Bent Details | 409‐2.04(03),409‐2C(deleted) and 409‐2D | Stage 3 submittals on or after March 1, 2025 |
| 24-12 Rev. | 09/11/24 rev. 10/11/24 | Semi‐Integral End Bent Details | 409‐3.03,409‐3A and 409‐3B | Stage 3 submittals on or after March 1, 2025 |
| 24-11 | 08/14/24 | Preliminary Geometrics Review for Non-Conventional Intersections | Section 14-2.01(03) | As Noted |
| 24-10 | 08/14/24 | Pavement Patching Tables | N/A | As Noted |
| 24-09 | 08/14/24 | Buy America Certification Procedures for Utilities and Railroads | Sections 104-2.02, 104-2.02(01) (new), 104-2.02(02) (new), Sections 105-1.04(03) and 105-1.04(04) | Immediately |
| 24-08 | 06/19/24 | MOT on High-Volume Interstate Highways | N/A | Immediately |
| 24-07 | 05/14/24 | 2024 INDOT Standard Drawings | N/A | Lettings on or after September 1, 2024 |
| 24-06 | 04/11/24 | IHCP Contract Documents | N/A | As noted |
| 24-05 | 04/11/24 | PROWAG Elements Phased Implementation | N/A | Lettings on or after July 1, 2028 |
| 24-04 | 04/11/24 | Pavement Design Process | IDM Chapter 601 sections 601-4.0, Figures 601-4A thru -4F (deleted), 601-5.0, 601-5.01, 601-5.01(01), 601-5.01(02), 601-5.01(03), 601-5.01(04), Figure 601-5A, 601-6.0 Chapter 602 Fig 602-3EE Chapter 604 sections 604-1.01, 604-1.04, 604-1.05, 604-2.01, 604-2.02, 604-2.03, 604-2.08, Figures 604-2A thru -2F(added) Editable Document 601-6.0.2, Pavement Design Request form | Immediately |
| 24-03 | 02/12/24 | Waterproofing Membrane and Partial Coating Limits | IDM Sections 407-2.01(03), Figure 407-2A (deleted) | Contracts Letting on or after September 1, 2024 |
| 24-02 | 01/09/24 | Lightweight Concrete, Threaded Tie Bar Assemblies, and Concrete Cover | IDM Sections 405-2.07(06) (new), 405-3.13 (deleted), and Figures 405-1A, 405-2C, 405-2AA, 405-3E | As Noted |
| 24-01 | 01/09/24 | Subgrade Treatment | IDM Chapter 603-4.0 | Lettings on or after June 1, 2024 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 23-21 | 12/08/23 | HMA Pavement PG Binder | IDM Chapter 601-2.0, 601-3.0, 601-5.01(04), and Fig. 601-5C IDM Chapter 602-3.02, 602-3.02(01) thru -3.02(03) IDM Chapter 607-1.0, 607-1.01 |
Lettings on or after September 1, 2024 |
| 23-20 | 11/15/23 | Extended Pile Bents and Wall Pier on Single Row of Piles | IDM Chapter 409-6.01(01), 409-6.03(05), 409-6.04(01), 409-6.04(02), 409-6.04(04), Figures 409-6B and 409-6C | Stage 1 submittals on or after January 1, 2024 |
| 23-19 | 11/15/23 | Joint Probability Analysis | IDM Figure 203-2G | Hydraulic Design submitted or completed on or after November 15, 2023 |
| 23-18 Rev. | 11/15/23 rev. 3/12/24 | Survey Requirements | IDM Chapter 26 | Design Survey on or after November 15, 2023 |
| 23-17 | 10/16/23 | Placing and Terminating Temporary Traffic Barrier | N/A | Lettings on or after December 1, 2023 |
| 23-16 | 10/16/23 | Public Rights-of-Way Accessibility Guidelines (PROWAG) | N/A | Lettings on or after July 1, 2024 |
| 23-11 | 09/14/23 | Payment for Elastomeric Bearing Assemblies | IDM Chapter 409-7.03(01) | Lettings on or after June 1, 2024 |
| 23-10 | 08/14/23 | Bridge Painting | IDM Chapter 17-5.11 | As Noted |
| 23-08 | 07/11/23 | Railroad Flagging | IDM Chapter 105-3.03 | Contracts letting on or after January 1, 2024 |
| 23-07 | 07/11/23 | Guardrail End Treatments | N/A | Lettings on or after October 1, 2023 |
| 23-03 | 05/12/23 | Stormwater Management | IDM Chapter 14-2.01(07), 14-2.03(03), 14-2.03(10), 14-2.04(06), 14-2.05(03) , 14-2.05(05), 17-6.02, 17-6.03, 17-6.04 and 205-4.0 | Lettings on or after September 1st, 2023 |
| 23-02 | 05/12/23 | Void Reducing Asphalt Membrane for Asphalt Paving | IDM Chapter 602-3.02 | For lettings on or after May 1, 2024 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 22-22 | 11/10/22 | Post-construction Stormwater Management | IDM Chapter 204 | As Noted |
| 22-17 | 09/13/22 | AASHTO LRFD Bridge Design Specifications | N/A | Stage 2 submittals on or after March 1, 2023 |
| 22-05 | 04/20/22 | Concrete Median Barrier for Interstate Routes | N/A | Immediately |
| 22-01 | 01/06/22 | Stage 2 Documents for Publication | IDM Chapter 14, Sections 14-2.01(07), 14-2.04(06), 14-2.05(03), 14-2.06(02), 14-2.07(02), and 14-2.08(02) |
Stage 2 Plans on or after January 06, 2022 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 21-18 Rev. | 09/09/21 rev. 02/09/22 rev. 07/11/2023 | Scour Requirements for Bridge Preventive Maintenance Projects | IDM Chapter 14, Sections 14-2.05, 412-2.0, and Figure 412-2C(Rev.) | Stage 1 Submittals on or after October 1, 2021 |
| 21-04 | 03/11/21 | Full Depth Reclamation (FDR) Projects and Rule 5 Permits | N/A | Immediately |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 20-14 | 08/06/20 | Preventative Maintenance and 3R Design Criteria for Freeway and Interstate Resurfacing Projects Attachment: August 2020 Q&A for Design Memos 20-13 & 20-14 |
N/A | Immediately |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 18-26 | 11/08/18 | Pedestrian Pushbutton and ADA Plan Details | 51-1.06(03) | Stage 3 Submittal on or after March 1, 2019 |
| 18-20 | 08/06/18 | Bridge Aesthetics Policy | N/A | Immediately |
| 18-05 | 03/05/18 | Plan Note for TAC Approved ADA Inquiries | N/A | Stage 3 Submissions on or after April 2, 2018 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 17-20 | 09/05/17 | Complex Bridge Design Requirements | N/A | Immediately |
| 17-17 | 08/07/17 | Manual for Assessing Safety Hardware (MASH) and New W-beam Guardrail and Guardrail End Treatment Standards Attachment: Pay Items Associated with MGS W-Beam Guardrail and Related Systems |
N/A | NHS Routes: Letting on or after January 1, 2018 Non-NHS Routes: Letting on or after July 1, 2018 |
| 17-10 | 05/11/17 | Manual for Assessing Safety Hardware (MASH) and New W-beam Guardrail and Guardrail End Treatment Standards Attachment: Midwest Guardrail System Assembly Figures, AASHTO/FHWA Joint Implementation Agreegement for MASH Memo |
N/A | NHS Routes: Letting on or after January 1, 2018 |
| 17-04 | 03/16/17 | Culvert Asset ID Number Attachment: Culvert Asset ID Numbering System |
N/A | Stage 3 on or after May 2017 |
| 17-02 | 02/02/17 | Rural Interstate Shoulder Width | N/A | Immediately |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 16-35 | 11/21/16 | Undistributed Quantities | N/A | Immediately |
| 16-10 | 03/16/16 | NEPA Compliance and Waterway Permitting for Bundled Projects Attachment: INDOT Environmental Memo |
N/A | Immediately |
| 16-01 | 01/05/16 | Structure Number in ERMS, SPMS, and on Plans Attachment: Example |
N/A | Immediately |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 13-09 | 04/12/13 | Small Structure Replacement, Guardrail Runout Length Attachment: RDG Table 5-10(b) |
Chapters 49 & 55 | Preliminary Field Check on or after June 1, 2013 and as noted |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 11-09 | 04/05/11 | High-Tension Cable-Barrier System (CBS) Attachment: RSP 627-R-546 Attachment: RPD 627-R-546d |
49-5.01(04) | Lettings on or after May 11, 2011 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 05-34 | 11/9/05 | Concrete Railings & Moment Slabs at Mechanically Stabilized Earth (MSE) Wall Systems Attachment: 706-R-504 RSP & RPD |
49-4.01(05) | 02/15/10 |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 03-07 | 07/02/03 | Policy for Context Sensitive Solution | N/A | Immediately |
| Memo Number | Memo Date | Subject | Affected IDM Section | Effective Date |
| 01-14 | 12/10/01 | Water Main & Sanitary Sewer Construction in Contracts | N/A | Immediately |