Current Design-Build Practices for Transportation Projects

8. Schedule

The following is an overview of each agency's scheduling procedures. This information is based on responses to the questions in Section 7 of Appendix 3.

8.1. Establishing Completion Deadlines

The first question addressing schedule issues in the original survey requested information regarding how contract completion dates were set and how schedules were used in the evaluation and selection process.

Most agencies set the completion dates or contract times in their RFP documents. However, schedule information was solicited and used as part of the evaluation and selection process.

8.2. Early Completion Incentives, Liquidated Damages, Stipulated Damages

Almost all agencies in the original survey provided for liquidated damages (LDs) and/or stipulated damages (SDs). Early completion incentives were not uncommon, but not universally provided.

Typically the amount (rate) of LDs and SDs were determined using standard agency formulas. For toll road projects, the rate was based on estimated loss of toll revenues.

The amount of incentive for early completion was directly tied to toll revenues in the case of toll road projects (for example, 70% of net revenue for period up to contractual completion date). For non-toll projects, the amount was generally established based on the importance of early completion.

Some projects provided incentives payable throughout the project (not just at final completion) for on-schedule (or better) performance at predetermined intervals during the project.

MnDOT (2008) On the I-35W design-build bridge replacement contract, MnDOT used a locked incentive date (essentially an A+B bidding provision) with a $7 million lump sum incentive and a graduated early completion incentive schedule with a maximum total incentive of $27 million. The contract provisions were successful in providing the incentive for the design-builder to finish the project 100 calendar days in advance of the proposed completion date. With the September 18, 2008 completion date, the design-builder earned a $25 million incentive payment. MnDOT used a $200,000/day contractual incentive / disincentive clause based on a calculated user impact of $400,000 per day.

8.3. Required Schedule Submittals and Remedies Available for Failure to Submit Schedules

Most agencies in the original survey required submittal of schedules with the proposal, which was used during the evaluation and selection process. All required schedules during the contract, although the frequency of updates varied. The most common remedy available for failure to submit required schedules/updates was suspension of payment (rarely used).

Some agencies required varying levels of detail for schedule submittal with the proposals and after award. Generally preliminary schedules were required at proposal and early in the project, with more detail required as the work progressed.

8.4. Schedule Float

The original survey addressed "ownership" of float. Agencies had a variety of approaches from "Project Float" (at times referred to as "first come, first served"); to Contractor-owned, or owned by the entity that generated the float. There were indications that the latter approach was difficult to measure and administer. The preference seemed to be the "Project Float" approach.

8.5. Recovery Schedule

The fifth schedule question solicited information regarding requirements for Recovery Schedules and the triggers for same.

Most agencies required a recovery schedule if progress fell behind a specified amount. The actual triggers varied, but there were close similarities among five agencies because their contract provisions were based on a similar model.

8.6. Recommended Changes for Future Projects

Only three agencies in the original survey made recommendations for changes in how schedule issues were addressed:

AZ DOT (Jan 2002)

AZ DOT recommended use of A+B bidding that allows contractor to drive schedule.

TCA (Jan 2002)

TCA recommended that float be Project Float rather than owned by entity generating it.

WSDOT (Jan 2002)

WSDOT recommended that the contractor be allowed to set start and completion dates in proposals with the thought that this approach might reduce impact of construction on the public.