Sioux City weighs rebidding $465m WWTP upgrade as Kiewit finishes preconstruction

Sioux City weighs rebidding $465m WWTP upgrade as Kiewit finishes preconstructionWith the 100% design complete for the largest capital project in the city's history, the Sioux City Council must decide whether to accept Kiewit’s guaranteed maximum price or return to the open market in hopes of securing lower construction costs.

The $465-$470 million WWTP rehabilitation is mandated by a consent order from the Iowa Attorney General and the Department of Natural Resources.

Hazen and Sawyer has completed the 100% design, and Kiewit has concluded its preconstruction services under a CMAR contract awarded last year.

Council members expressed optimism that stabilizing market conditions and easing supply chain issues could yield lower prices if the project is put out for competitive bidding.

Phase 1 of the rehabilitation must be completed by December 31, 2031, leaving the city with a tight timeline to finalize its procurement strategy.

Sioux City, Iowa, is approaching a critical procurement juncture for its $465 million to $470 million wastewater treatment plant (WWTP) rehabilitation. During a July 6 meeting, city officials announced that the city council will soon vote on whether to proceed with Kiewit for the construction phase or rebid the project to the broader market. The mega-project, described as the largest expense in the city's history, is mandated by a consent order from the Iowa Attorney General and the state Department of Natural Resources (DNR) to meet environmental regulations. Phase 1 of the project, which focuses on rehabilitating the existing plant without adding capacity, carries a strict completion deadline of December 31, 2031. Phase 2 must be finished by the end of 2035. Consulting engineer Hazen and Sawyer has reached the 100% design milestone. Kiewit, functioning as the Construction Manager at Risk (CMAR), has been under contract since February of last year to provide preconstruction services. According to a recent WWTP Reconstruction and Design Advisory Committee update, Kiewit recently evaluated trade and equipment package bids to develop a Guaranteed Maximum Price (GMP) for the city's consideration. With Kiewit's preconstruction scope now fulfilled, the council is treating the moment as a "fork in the road." A council member noted that while Kiewit is highly qualified, the city has the legal right to reject the GMP and issue a competitive bid for the construction phase. "Prices have settled down a little bit from all of the shortages that we had due to COVID and transportation and some of the tariff things," a council member stated during the meeting, suggesting that a rebid might capture current market corrections and lower the final price tag. The council is expected to deliberate the GMP versus hard-bid approach at its next meeting, balancing the potential for cost savings against the risk of delaying a tightly mandated compliance schedule.