SDOT BIM Protocol

The Seattle Department of Transportation (SDOT), in partnership with Seattle Information Technology, released the technical memorandum below that lays out the requirements, protocol, and best practices for using cutting-edge digital design tools on city transportation construction projects. This guide is like a playbook for how to plan and start new construction projects, whether working with outside experts or handling things in-house.

At the heart of this guide is something called Building Information Modeling (BIM). Think of BIM as a high-tech way to plan and manage construction projects. It uses digital technology to create a shared space where everyone involved in a project can collaborate. This space connects with other important systems, like maps and asset management tools, making it easier to keep track of project data.

One of the advantages of BIM is that it lets project teams use cloud computing to handle all sorts of data, like 3D scans and aerial photos. This means they can create detailed models, make drawings with shared notes, and work together more smoothly. It’s like having a supercharged toolkit that helps everyone stay on the same page.

Technical Memorandum

Updated 9/5/2024

Background

In 2020, the City of Seattle implemented the Autodesk Construction Cloud (ACC) software and began piloting CAD file management for construction projects on ACC. On September 5th, 2024, SDOT Engineering Services began initiating all Capital Projects in the ACC environment and discontinued managing active CAD files on the internal network. This means that all consultant designed CAD files and City Department designed CAD files created for SDOT Capital Projects must be developed and managed on ACC.

Purpose

The purpose of this Tech Memo is to outline the current protocol for CAD file management for SDOT Engineering Services in-house design projects, consultant design projects, SPU prepared surveys, and consultant prepared survey files.

Glossary of Terms

  • BIM Standards - This document references the City of Seattle BIM Standards, hereafter referred to as “BIM Standards”, which can be found on https://seattle.gov/tech/bim.
  • CAD - Computer-aided-drafting, hereafter referred to as CAD, is the use of computers to graphically aid in the creation, modification, analysis, or optimization of a map or design.
  • CPD CAD Supervisor - The SDOT Capital Projects Division CAD Supervisor, Melanie Owings, hereafter referred to as “CPD CAD Supervisor”, can be contacted at melanie.owings@seattle.gov.
  • ACC - Autodesk Construction Cloud, hereafter referred to as ACC, is the City of Seattle BIM platform and can be accessed by logging into https://acc.autodesk.com. Consultants must apply to access ACC and enter melanie.owings@seattle.gov or an authorized proxy in the City of Seattle Partner Contact Email field for approval.
  • BIM Execution Plan - A BIM Execution Plan (BIMxp) documents specific requirements for a project such as asset and design collaboration requirements. Seattle Information Technology Department (ITD) uses the BIM Execution Plan database to notify project teams about updates and changes to the BIM Standards and software.
  • Transmittals - Method of transmitting files on ACC.

Requirements and Expectations

  1. Electronic CAD drawing files must conform to the current BIM Standards.
  2. All SDOT projects must be set up on the City of Seattle ACC hub.
    1. All drawings must be edited on ACC so that the version history is tracked and visible to SDOT.
    2. Autodesk Desktop Connector updates must be coordinated with the project team, so all members are on the same version.
    3. Autodesk BIM Collaborate Pro is required for all team members who create Autodesk Civil 3D data shortcuts.
  3. Drawings that depict geospatial elements must use templates that have the standard coordinate system applied per Section 2.0 of the BIM Standards.
  4. Electronic computer-aided-drafting (CAD) drawing files must be created using either AutoCAD or Civil 3D versions as required in Section 2.1 of the BIM Standards. Civil engineering/mapping software must be able to produce the following deliverables:
    1. PDFs of plan set (must use COS-ROMANS.TTF)
    2. Publish the following assets to ArcGIS with Autodesk Civil 3D or AutoCAD Map 3D:
      • Drainage and Wastewater (DWW) System: Civil 3D Pipe Networks
      • Water System: Civil 3D Feature Lines and Cogo Points
      • Irrigation System: Civil 3D Feature Lines and Cogo Points
      • Roadway Paving Edges: Civil 3D Feature Lines
      • Roadway Channelization (paint markings): AutoCAD Map 3D Lines and Blocks
      • Roadway Signage: Civil 3D Cogo Points
      • Roadway Signalization: Civil 3D Feature Lines and Cogo Points
      • Street Trees: Civil 3D Cogo Points
      • Electrical Site Plans: Civil 3D Feature Lines and Cogo Points
  5. The prime consultant is responsible for the coordination, review & compliance of BIM Standards for any/all CAD work performed by a sub-consultant whom they have hired.
  6. All electronic CAD drawing files (DWG, DST, DWF and PDF formats) must be transmitted to the CPD CAD Supervisor at 30%, 60%, 90% completion for a review of their conformity to the BIM Standards & presentation requirements documented therein. Contact the CPD CAD Supervisor with questions.
    1. Reviewed drawings/plan sets that do not conform to current BIM Standards will be returned with comments & requested corrections.
    2. Requested corrections are required to be completed prior to the next submittal.
  7. At 100%, time of advertisement, production of conformed drawing set, contract award or notice to proceed - the consultant is required to provide:
    1. One complete, full size pdf document containing all plan sheets produced per Section 5.1 of the BIM Standards, transmitted to the CPD CAD Supervisor to route for electronic signatures via Adobe Sign.
    2. Source drawings transmitted to the CPD CAD Supervisor in the required AutoCAD or Civil 3D format.
  8. All Design Change Drawings must meet the Design Change Standards in Section 4.3 of the BIM Standards.
  9. All As-Built/Record Drawings must meet the Record Drawing Standards in Section 4.4 of the BIM Standards and any/all documentation or requirements as noted in the City Standard Plans & Specifications manual.

BIM Project Setup

At the initiation phase of an SDOT Capital Project, the SDOT Project Engineer must complete the SDOT Project Intake form to notify the CPD CAD Supervisor to prepare to setup the BIM project. The SDOT Project Engineer must also complete the BIM Execution Plan which will be submitted to Seattle Information Technology and the CPD CAD Supervisor to kick-off the project file structure development. The BIM Execution Plan will produce a draft of technical requirements to share with the project team and to inform SPU about expected Record Drawing (As-Built) work for this project. The CPD CAD Supervisor will set up the project on the Autodesk Construction Cloud according to the BIM Execution Plan, invite team members, and assign folder permissions.

Topographic Surveys

If required, the Project Engineer must submit an SPU Land Survey request or engage the services of an external land surveying firm (consultant land survey contract requirements). Topographic Survey (Topo) drawings may be developed outside of the ACC environment at SPU or at a consultant’s discretion. The final product deliverable will, however, need to be uploaded to the project’s ACC directory. SDOT will use the Topo drawing to XREF into design drawings and plan sheets. All alignments and surface must be contained in the Topo drawing and data shortcuts must be created from it. The Right-of-Way drawing is to be used for Survey Control only. If edits are needed to a Topo drawing in ACC, this work must be performed by the surveyor, with minor exceptions being moving text, or minor formatting work. Any minor work along these lines must be done by a person assigned by the CPD CAD Supervisor.

Autodesk Licensing

Autodesk has a “bring your own license” model for desktop and cloud applications, which means that consultants and contractors are expected to have the required software to execute and deliver the project. Here are the Autodesk Construction Cloud licensing options:

Learn More

If you’re curious to learn more about BIM standards and protocol, you can check out the full details on the City of Seattle’s BIM page.

Information Technology

Rob Lloyd, Chief Technology Officer
Address: 700 5th Ave, Suite 2700, Seattle, WA, 98104
Mailing Address: PO Box 94709, Seattle, WA, 98124-4709
Phone: (206) 684-0600
Phone Alt: Cable TV & Internet Discount Information: (206) 684-8498
SeattleIT@seattle.gov

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