Monroe County Begins 18-Month Bridge Work on Card Sound Road

Two bridge construction projects are now running simultaneously on Card Sound Road, with the westbound lane already closed at Tubby's Creek Bridge and preparatory work underway at Mosquito Creek Bridge less than 3,500 feet away. The overlap means drivers navigating this stretch face single-lane alternating traffic at back-to-back chokepoints for what Monroe County estimates will be an 18-month construction window, weather permitting.

At each bridge, the contractor has closed the westbound lane and installed temporary signals to route traffic through the remaining open lane in both directions. Monroe County will adjust signal timing during peak morning and afternoon commute windows to reduce queuing for drivers heading to and from Ocean Reef and other Upper Keys communities. Outside those adjusted windows, standard signal timing applies, and delays are likely when traffic volumes climb during tourist season.

Mosquito Creek Bridge entered the preparatory phase on March 12, with shoulder clearing and pavement widening now beginning alongside the active construction already underway at Tubby's Creek. Monroe County's March 24 announcement confirmed both work sites are active and outlined the sequencing: Tubby's Creek construction continues while Mosquito Creek moves from preliminary groundwork into full bridge work.

Card Sound Road is one of the limited overland connections between the Florida mainland and southern Monroe County. That bottleneck effect matters most in emergencies: with both bridges running alternating single-lane signals, response times for fire, medical, and law enforcement units crossing this corridor could increase, requiring agencies to account for potential delays in dispatch planning.

The shoulder clearing and pavement widening are not cosmetic. Wider shoulders on these structures improve clearance for maintenance vehicles and provide a critical safety margin during hurricanes, when utility crews and emergency equipment must move quickly through a road network with few alternatives. Once complete, the upgrades are intended to make Card Sound Road more reliable precisely when conditions are worst.

Monroe County urged drivers who regularly use the road to monitor the county's news page for project updates and sign up for official alerts. Alternate routes should be considered during peak commute hours and high-traffic weekends for the duration of the project.