Design Errors and Defective Concrete Blamed for Massive Delays in Miami Signature Bridge Project

A landmark Miami roadway project once envisioned as a $802 million transformation is now mired in lawsuits, delays, and mounting costs exceeding $400 million, according to court filings reviewed by NBC6 Investigates.

The “Connecting Miami” project, anchored by a dramatic 1,000-foot-long Signature Bridge over Biscayne Boulevard, was originally slated for completion in 2021. The current projected finish date is 2029.

The joint venture hired by the Florida Department of Transportation (FDOT) alleges that critical design errors by engineering firm HDR Engineering and defective concrete production caused years of delays and massive cost overruns.

According to lawsuits, HDR miscalculated wind loads in the bridge’s preliminary design, leaving it unable to withstand hurricane-force winds common in South Florida. The error was discovered before construction began, forcing a costly redesign that significantly increased structural complexity and materials.

The joint venture claims these changes caused multiple years of delay and more than $400 million in additional costs. HDR has denied wrongdoing, stating the original plans were conceptual and not intended for construction. The parties settled one lawsuit without an admission of fault, capped by insurance limits.

Further complications arose when a mechanical failure at an on-site concrete plant led to defective concrete being poured into structural elements for months before detection, requiring removal and repairs.

FDOT has cited weather, supply chain disruptions, utility relocations, and legal challenges as contributing factors but declined to answer whether taxpayers could be responsible for the added costs.

Transit advocates have criticized the project as a “boondoggle,” calling for greater transparency and accountability as drivers continue to face years of traffic disruptions.

Despite the setbacks, FDOT maintains that safety remains its top priority as construction continues.