Mare Island Causeway lift towers operational, but other construction delayed

VALLEJO – Numerous improvements underway on the Mare Island Causeway bridge have been delayed for environmental reasons, but lift towers once again allow boat passage to the Napa River.

The city said Thursday that the bridge’s vertical drawbridge lift span is operating on its normal schedule with no time restrictions as of July 1. 

However, some repair work including sidewalk installation has slowed temporarily due to nearby nesting activity of the California Black Rail, a threatened native species. The birds are currently nesting in the adjacent wetlands, and the city said that state environmental requirements prevent further construction activities from taking place during this period. 

“In coordination with the California Department of Fish and Wildlife, the city has a biologist to monitor the nesting of the birds, who will determine when the birds have cleared the area so full operations can resume,” the city of Vallejo said in a news release this week.

The bridge was built in 1934 as the connector between Vallejo and Mare Island. Following a 2016 upgrade project replacing a 50-foot span of bridge timber with steel, the bridge has had frequent operating issues which have disrupted boat and vehicle traffic to Mare Island. 

In April 2023, the bridge required repairs because it was not seated correctly, which left a gap in the westbound traffic lane. 

Then in May 2024, city officials said that due to obsolete parts in the bridge's aging electrical system, it could not be raised and lowered. The city chose to leave the bridge in the “down” position to allow pedestrian and vehicle traffic, while blocking most boat traffic. 

Recreational vessels frequently cross the Mare Island Strait on their way to Napa, and even small sailboats need the bridge raised to clear it. This issue continued into June 2024.

City staff later brought a request for $3 million in early 2025 to the Measure P Committee, requesting to use a portion of the fund to cover a gap in funding for repairs. But the committee at that time declined to recommend the allocation, saying the city had not been adequately transparent with Mare Island residents on the Causeway work.

This week, the city said other improvements have been made, such as adding light posts and light poles on the south side of the bridge.

However, other parts of the work are underway or delayed. Staff said that the installation of a guardrail post and handrail painting on the bridge’s south side are about 70% complete. Work beneath the bridge deck and on the deck surface remains ongoing, and the bridge logo’s installation will not take place until September.

That makes the project about 65% complete, according to the city. As it stands now, the estimated completion date for repairs has been pushed by several weeks, from mid‑February 2027 to March 2027.