Tampa Bay Estuary Program: to improve water quality, breach causeways

Old Tampa Bay: it’s the most northerly section of the Bay and furthest from the mouth – where the Sunshine Skyway Bridge is located – so that leads to the water there being the most stagnant. The executive director of the Tampa Bay Estuary Program told a St. Petersburg City Council committee this month that means there’s poor water quality, inconsistent seagrass recovery and summertime algae blooms by a genus called Pyrodinium, which is different from the red tide alga. But Ed Sherwood says there’s a way to improve the water quality in Old Tampa Bay – by constructing more pathways for water by breaching bridge causeways, thereby restoring water flow.

“These causeways are impeding circulation and could be contributing to the poor water quality conditions in Old Tampa Bay. And we’ve been working with the Florida Department of Transportation [DOT] since about 2015 to get them to think about breaching these causeways as they’re doing these bridge replacement projects.

“And in fact, there’s one going on right now. If you’ve passed over the Courtney Campbell Causeway on the Rocky Point side — the Tampa side — there’s actually being a breach constructed in the Courtney Campbell Causeway to improve water circulation north of the causeway on the Tampa side.

“So what we’re asking DOT to consider is doing that again when they look at replacing the Howard Frankland Bridge. And what we’re asking them to consider is on that western causeway approach, on the St. Pete side this time.

“And what we’re trying to achieve is basically that picture of what the Bay looked like prior to a lot of these bridges being constructed. Recreating the circulation patterns of the tide coming in and going out and not being obstructed by these causeways. Part of the reason why that particular algal species blooms in this portion of Old Tampa Bay is because the tidal circulation pattern goes up and creates a gyre. And the water just sits there and provides nutrient sources to that particular algal species and that persists through the summertime, until we get flushing rains and the Bay turns over, so to speak.

“What we’re trying to get DOT to consider is reestablishing some of those circulation patterns through those causeway breaches.”