Sweet Soundings: New Technology Provides Insights Into Tampa Bay

Enhanced Mobile Mapping with Emerging Technologies – EMMET for short – has an outsized mission to survey the shallowest reaches of Tampa Bay. Photo courtesy of USF-SP

Have you noticed a curious new watercraft of elfin proportions plying the shallows of Tampa Bay? If so, don’t worry – that’s just EMMET!

Enhanced Mobile Mapping with Emerging Technologies – as it is more formally known to its creators at USF’s Center for Ocean Mapping and Innovative Technologies (COMIT) and the Florida Flood Hub for Applied Research and Innovation – is a pint-sized pontoon boat, just six feet long and three feet at the beam. But the small craft has an outsized mission: to survey the shallowest reaches of Tampa Bay that are impossible to map from larger boats. And EMMET is well-equipped to do so: the uncrewed vehicle carries a multibeam swath mapping sonar, multiple GPS systems, lidar to help detect and avoid nearby objects, and four on-board cameras to provide a 360-degree view above the surface. It can operate in as little as one foot of water, giving it the agility to navigate the targeted 1-to-4-meter depth range with ease. And, EMMET can be guided remotely from a laptop or through an app, either on shore or from a larger, crewed vessel. 

“Think of it like mowing a lawn,” Matthew Hommeyer, a technical operations manager at COMIT, describes the surveying process. “The swath mapping sonar gathers strips of coverage, which we can then overlap and stitch together.” The result is a much clearer picture of the bay floor – seen not with light, but with sound. 

But why would you want a clearer picture of the shallows? Hommeyer cites three important reasons. The first and most obvious is navigation. With a bay bottom that is constantly shifting due to ordinary forces such as tidal movement, and extraordinary events such as hurricanes, assessing present depth and predicting future movement of sediments is critical for keeping people and property safe. When the 2024 hurricanes closed the Port of Tampa, for instance, checking and clearing shipping channels – and doing so quickly – was essential for bringing necessary resources, such as fuel, back to the Bay area. 

 Another important sector that relies on this kind of information is the so-called blue economy. Fisheries, aquaculture, sand mining, petroleum extraction, shipping, and offshore wind energy all depend on a clear understanding of bathymetry, or how the ocean floor behaves. One application that Hommeyer and his collaborators are now working on is particularly relevant in this regard: they are using EMMET to map seagrass beds, a habitat which is at the foundation of many of the Bay’s commercial fisheries. Seagrass surveys have traditionally been conducted with aerial photography during the winter, when water is clearest. By contrast, EMMET can map these areas using sonar during the summer growing season, potentially providing a more accurate measurement of their extent.

What’s a little less obvious, but no less important, are the implications for coastal community planning and resilience. Having a more precise picture of Tampa Bay’s coastal shallows can help produce more accurate predictions for storm surge, enabling communities to respond – and, if necessary, evacuate – in advance of the danger. In the long term, this kind of data could influence insurance policies and help drive planning decisions about where to build. 

Shallow water bathymetry, quips Hommeyer, carries with it a paradox: “When things are at their best, you don’t notice it. But in times of crisis, then you start to see it.” 

But EMMET is not the only mapping system on the job. Another COMIT initiative, Crowd the Bay, is using similar technology to crowd source data from Tampa Bay boaters. Any boat with an integrated depth sounder, be it a humble fishing vessel or a yacht, can get in on the act by installing a COMIT-provided data logger that feeds depth soundings back to a central database. 

When Ryan Dilkey, associate director of the Eckerd College Waterfront, heard about this, he knew he had the perfect vessels to assist. Eckerd’s Search and Rescue team (ECSAR) – the United States’ only student-staffed maritime search and rescue team at an undergraduate college – operates four rescue boats that respond to more than 500 distress calls per year in the Tampa Bay area. In February of 2024, ECSAR installed data loggers on three of its boats. 

Since that time, ECSAR craft have logged well over a million (and counting) soundings in the database, making them what Hommeyer calls “the rockstars” of COMIT’s crowd sourced bathymetry program. For his part, Dilkey is already seeing the benefits for ECSAR; geolocated sounding records can be used to trace a vessel’s route and communicate about search efforts to the Coast Guard.  

“In cases like that,” says Dilkey, “it really helps to know you did everything right.” Dilkey is also excited about the technology’s potential to create new visualizations for navigation.

As for Hommeyer, the excitement about potential applications for the technology also comes with the thrill of discovery. He is proud to be sponsored by the nation’s oldest civilian scientific agency, the National Oceanic and Atmospheric Administration’s Office of the Coast Survey (originally founded by Thomas Jefferson in 1807) to continue this important work.  

“It’s like a scratch card,” he reflects, “seeing the bay floor emerge in real time, watching it roll out in real time across the screen. It’s fun. It’s always something no one has seen before.”