8.1.4 Design Development for Sewer and Storm Drain Projects

Purpose

This Procedure describes more specific aspects of the preparation of design and construction documents for sewer and storm drain projects managed by the Bureau of Engineering (BOE). For general or typical aspects of the design process applicable to all project types, please refer to Procedure 8.1. For specific design methods, procedures, and guidelines refer to the Sewer and Storm Drain Design Manuals.

References

• Standard Specifications for Public Works Construction (Green Book) – Latest Edition

• American Public Works Association – Standard Plans for Public Works Construction

Responsibilities

• Project Manager (PM): The PM is responsible, normally through the efforts of the Project Engineer, for the completion of the design documents within the schedule and to the satisfaction of the Client. The PM is also responsible for ensuring that quality assurance/quality control (QA/QC) procedures are followed and that the project remains within the approved budget and is consistent with the concept presented in the Pre-Design Report.

• Project Engineer (PE): The PE will be responsible for the preparation, coordination, updating, and revision of the design and construction documents. The PE is required to follow the procedures outlined in this Chapter to protect public health, safety, welfare, and to ensure successful completion of the project. These procedures facilitate the production of accurate, consistent, complete, and understandable final plans and specifications, to be used to initiate and complete the construction of a project. The PE is responsible for coordinating the design documents with all of the design disciplines that have contributed to the project.

Procedure

The Design Process

The preparation of final design documents starts with the transition from Pre-Design activities to development of detailed design and finishes with the final construction plans and specifications. During the Design Process, the PE and Design Team will implement the Pre-Design Report along with survey, right-of-way, geotechnical, and utility information to produce a set of final construction plans and specifications in accordance with current design standards. The Design Team will also document and present the plans and specifications to the Client/User for approval.

Each Design Group within the City may have their own Design Checklist. In the Wastewater Conveyance Engineering Division (WCE) or Sewer Design, there are several checklists that are to be used as part of the Design process.These checklists are, but not limited to the:

1. Project Engineer/Project Manager Checklist

2. Design Review Checklist

3. E2020 Records Management Checklist

4. Plan & Profile Checklists

5. Constructability Review Checklist

6. Constructability Review Comments & Response Form

7. Deputy City Engineer Plan Signing Checklist

8. Ready to Advertise Checklist

These checklists will assist the Design Team in delivering the project, record keeping and addressing concerns Management may have.

Development of the Technical Specifications should begin with the initiation of the Design Phase. Refer to Procedure 8.2 and Chapter 10 for additional discussion of specifications, bid documents, and the bid proposal.

Construction documents are the final plans, specifications, and special provisions. Construction documents must be accurate, consistent, complete, and understandable. The PE shall assemble an accurate, consistent, and complete set of bid documents, including construction drawings of all design disciplines and a complete set of project specifications with bidding, construction, and completion instructions (the Project Manual) for the project.

Special Notes:

• The BOE has adopted the Los Angeles County Department of Public Works (LACDPW) method of hydrologic design. As of December 3, 2004, per Special Order No. 007-1299, the LACDPW method is the standard for hydrologic design.

• The BOE has modified the sewer design method contained in Section F250 of the Sewer Design Manual. Refer to Special Order No. 007-1204 for specifics.

Typical Activities

1. Prepare design drawings from the approved Pre-Design Report and selected project alternative/alignment.

2. Participate in regular project reviews and discussions with the Client/User.

3. Document Client/User meetings and monitor/evaluate the impact of decisions on project scope, cost, and schedule.

4. Actively coordinate the work of Consultants (if used) during the design phase.

5. Develop a schedule for preparation of construction documents with interdisciplinary reviews consistent with the 50% and 90% design milestones.

6. Implement the QA/QC Plan as discussed in Chapter 9 of this Manual to assure technical accuracy and clarity.

7. Update the construction cost estimate at the 20%, 50%, 90% design milestones and compare it to the project budget.

8. Periodically review design costs (design team time charges and consultant costs) and compare to template values for the project.

9. Develop a plan sheet index consistent with BOE labeling and numbering standards which includes all design disciplines for the project.

10. Prepare a Schedule for preparation of construction documents with milestone markers and reviews as appropriate to allow for proper coordination with other disciplines.

11. Investigate product literature and/or question vendors/manufacturers about material selection information.

12. Conduct third party constructability review of all construction documents.

13. Verify that revisions and corrections from interdisciplinary reviews, document mock-ups, and redlined drawings are properly addressed.

14. Cross-check products and materials called for in the Special Provisions for consistency with corresponding terminology and descriptions in the project plans.

15. Closely evaluate the impact of design changes past the 50% milestone on the project plans and specifications.

16. Conduct final document review for compliance with applicable codes, regulations, and procedures.

17. Obtain required approvals and permits consistent with the timelines in the project schedule.

18. Determine project staging to identify the need for project detour and construction traffic lane requirements.

19. Include plan sheets for the Bureau of Street Lighting and Department of Transportation.

Typical Issues

1. Comprehensive substructure research and identification.

2. Constructability and coordination with utility companies.

3. Interfacing with other design disciplines.

4. Specialized structural and/or geotechnical requirements for storm drains and sewers.

5. Clarity and organization of construction materials and equipment to be used in terms of sequence of construction, cost, and interface on the job site.

6. Basic layout of all design features to assure design integration, coordination, and adequacy.

7. Finalizing design choices in plan, elevation, and cross-section.

8. Design schedule and budget.

9. Project funding Cash Flow Analysis.

10. Special material research in relation to budget and construction schedule, specifically, identify long lead time items.

11. Coordination with other agencies (e.g., Los Angeles County Department of Public Works) and compliance with Cooperative or Master Agreements (if applicable).