Photo By Thomas Deaton | Operational equipment is seen onboard the DB Avalon dredge, February 19, 2025, as...... read more read more
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On the bridge of the DB Avalon, a dredge captain interprets data and live imagery from the nearly two-dozen screens that surround his seat, making occasional inputs to the small, lighted switches and joysticks at his control. The vessel’s immense mechanical components respond, visible through a large wall of windows set high above the work platform, and the two forward spuds (tall metal pilings used to maintain the barge’s location) climb upward, allowing the entire operation to “walk” along the bed of the Chesapeake Bay south of Baltimore.
Not long after, a crane operator, sitting in a separate cab at the opposite end of the barge, lifts North America’s largest clamshell dredge up and to the left, revealing from the gray water a clamped dredge bucket full of material from the bottom of the federal navigation channel that leads to the Port of Baltimore. In one swift motion the bucket rises — its innovative, hybrid-powered system regenerating energy in the process — and opens, emptying its murky contents into a nearby scow before returning to the seabed to repeat the cycle.
This repetition, carried out not only every winter but 24 hours a day, seven days a week when operating, is one cog of a clock that has been ticking in the Chesapeake Bay and in Baltimore Harbor for nearly 200 years, quietly carving a network of ‘underwater highways.’
“The importance of this dredging is to keep all the channels to their authorized project depth,” says U.S. Army Corps of Engineers, Baltimore District (USACE) project manager Kevin Fenyak. “As time goes on, the channels shoal in and get shallower, and it makes it harder for the boats to navigate in and out of the harbor.”
The necessity for this effort stems from simple supply and demand. As the volume and draft-depth of shipping have increased with swift advancements across the last century, so too has the demand for dredging and the extensive USACE excavation and development of Baltimore Harbor.
The early work
Army engineers’ earliest work in the region began with the transformation from 1798 to 1802 of a temporary earthwork defense at the entrance of Baltimore Harbor (Fort Whetstone) into the recognizable Fort McHenry, the famed inspiration for “The Star-Spangled Banner” and a Baltimore landmark. Fort Carroll (on a nearby Patapsco River shoal) soon followed, and by the Civil War Baltimore was one of the best defended ports in the world.
After the War of 1812, though, when the cannons cooled and the fledgling country's attention turned inward, engineers were instead tasked with civil works programs that contributed to its westward expansion and to economic development throughout its waterways.
Baltimore District surveys in 1830 determined the harbor’s controlling depth to be 17 feet from the Chesapeake Bay to Fort McHenry. Congressional appropriations for early dredging came in 1836 and again in 1852, when the River & Harbor Act authorized a channel depth of 22 feet from Fort McHenry to the Chesapeake Bay off Swan Point. The construction of this new channel, led by Baltimore District Commander Capt. Henry Brewerton, opened the shallow Patapsco to a new maritime economy — and still bears Brewerton’s name.
His successor in this effort, though, faced the hydrological inevitability that continues to require Baltimore District’s annual maintenance dredging today, including intense shoaling that plagued the lower portion of Brewerton’s channel, where its design allowed the currents of the Patapsco to fill in the channel faster than dredging efforts could maintain.
That successor, then-Maj. William Craighill, would spend a total of 30 years in command, overseeing what became the modern shipping channels in the Port of Baltimore and negotiating with the riverine currents in such a way that their forces would assist in preventing sedimentation rather than cause it. Much like his predecessor, the aptly-named Craighill Channel remains the main entrance to the Port of Baltimore.
Digging deeper
By the 1890s, Congress had again authorized a new depth: 30 feet across what were now 600-foot-wide channels. With these efforts underway by the start of the Spanish-American War in 1898, it meant USACE efforts had produced one of the world’s largest harbors, continuing to contribute to such a title with additional authorizations in 1915 (35 feet) and 1930 (37 feet) for the Chesapeake Bay’s busiest channels.
Maryland’s Eastern Shore and other Bay communities also saw the deepening of their channels as USACE completed projects in towns like Rock Hall, Salisbury, Cambridge, and even Washington, D.C., where dredge fill material was used to build the modern footprint of the capital city’s monument-laden West Potomac Park. Cambridge alone would more than double its population between 1870 and 1910, the 40-year period after the 1870 Rivers and Harbor Act authorized its deeper, federally maintained channel, allowing it to accommodate the increasingly large commercial vessels of the day.
Throughout World War II, Baltimore became home to one of the two national emergency shipyards (located on opposite ends of the country, in Maryland and in Oregon), with the Bethlehem-Fairfield shipyard launching a record-setting 384 Liberty ships from its location in south Baltimore and employing, at its peak, some 47,000 people. While the indulgence of dredging deeper was too great a cost in the penny-pinching of a wartime budget, maintenance dredging continued.
Then-Lt. Col. Oscar J. Poole, Baltimore District Commander, cautioned that iron and oil shortages “make it imperative that their shipment be expedited and not be delayed by boats grounded in a channel.”
This is still only a fraction of the economic impact of the Bay’s maritime economy but a clear highlight of the global implications behind the region’s channel maintenance. After the war, USACE again dredged deeper the main channels, with resumed appropriations and authorization to reach 39 feet (1945) and 42 feet (1958), along with periodic efforts to deepen approach channels like the Curtis Bay and Ferry Bar Channels and the entrance to the C&D Canal.
USACE reached its currently maintained depth by 1990 after the River and Harbor Act of 1970 authorized deepening both the main channel from Cape Henry to Fort McHenry and the Curtis Bay Channel to 50 feet, allowing for the Port of Baltimore’s deep draft vessels to safely navigate the 175 mile stretch north from the Virginia Capes. The Water Resource Development Act of 1999 authorized a 50-foot turning basin at the head of the Fort McHenry channel, along with deeper anchorages for two of the Port’s terminals.
Such improvements have played a critical role in bolstering the economic activity of the Port, the 11th largest in the nation and first for “roll on/roll off” farm and construction machinery. Its cargo in 2023 alone had a value over $80 billion, setting a Baltimore record as it handled 52.3 million tons. Over 20,000 direct jobs are generated by the Port’s activities, with nearly ten times more employed by related industries, including the import-export firms moving goods and the workers on assembly lines and in coal mines far from the Chesapeake coasts.
Raising sand
As early as Craighill’s command, the excavation of such immense quantities of dredge material went without an answer to its most common question: where does it all go? USACE historians estimate some 30 million cubic yards of material had been pulled from Baltimore’s channels by 1900, with the vast majority indiscriminately piled somewhere outside the channel, often just overboard nearby. This posed immense risks to the Chesapeake Bay ecosystem and its oyster beds, and it allowed the slow drift of material back into the very channels from which it had been removed.
“The oyster business is an important one to Baltimore and anything tending to destroy any part of it will be violently opposed,” warned then-Baltimore District Commander Col. Peter Hains in 1902, expressing the need for an alternative to deepwater dumping, which he had earlier argued could have negative impacts on the navigable waterways of the Bay.
Hains’ proposed alternative? Constructing an artificial island of dredged material, an innovative but ambitious suggestion which went unrecognized in his time, particularly when an understanding of the impacts of dredge material and other industrial and agricultural activities on the overall health of the Bay had yet to be summarized. After all, the entire Chesapeake Bay watershed stretches across five states — over 100 local governments — who, at least until the last century, likely saw little connectivity between their part and the whole.
This changed in 1961, when the Senate Select Committee on Water Resources tasked USACE with a general survey that led to Baltimore District’s “Chesapeake Bay Basin Study,” the first attempt by any government agency to assess the Bay in its entirety. The report’s bottom line: the population and economic booms of the surrounding region were a fundamental threat to the Bay’s water resources.
Pressures on wetlands, depleted fish populations, and developments built in tidal floodplains, all results of population growth, were combining into harmful impacts on the Bay system. Included in such causes was the increased scale of dredging, which could elevate salinity levels when combined with the more intense water withdrawals being made from the watershed’s rivers. Combine these factors with the famously erosive forces of Chesapeake Bay, where over 10,500 acres of remote island habitat have been lost in the last 150 years, and one can see the concern for recovery of such an interconnected ecosystem.
One site in particular, Poplar Island, which sits 34 miles south of Baltimore off the coast of Talbot County on the Eastern Shore, was home to a community of about 100 at the turn of the 20th century. But by the turn of the 21st, all that remained was a small cluster of islets, just four acres barely rising above the surface of the water. What had been several farms, a school, a church, a post office, and a sawmill had been reclaimed by rising seas and erosion.
But developments in environmental policies throughout the Bay and in dredge material management would instead help unlock a new life for the island that had been home to presidential retreats and once appeared on the maps of John Smith.
“I got a call from my boss saying the Corps of Engineers was going to build an island somewhere in the Chesapeake Bay,” said Justin Callahan, Chief of Baltimore District’s Civil Project Management Branch and a former Poplar Island project manager. “I’m thinking, ‘You’re going to do what? You’re going to build an island?’”
It was ambitious but true: in a 1997 agreement between USACE, the Maryland Port Administration, and numerous other federal and state agencies, it was decided to explore the possibility of using dredged material to rebuild the island to its approximate 1847 footprint of over 1,000 acres — taking a chance on the very idea Hains had proposed nearly 100 years prior.
To tackle such a project, USACE first constructed more than six miles of containment dikes around the perimeter of the future footprint, barriers of rock and stone inside which clean dredged material would be placed and allowed to “de-water,” maximizing its placement capacity, and managed for ecosystem progress over several decades.
“Every wetland cell we complete and design we then monitor for several years to see how it’s doing,” said Katie Perkins, who has also served as Poplar Island’s project manager.
The remote island habitat once lost to time and tide began taking shape again, and shortly after the first dredged material was placed on the island in 2001, ospreys, egrets, terns, herons, eagles, terrapins, and other wildlife began to call the restored island home. The island’s design includes the construction of uplands, tidal wetlands, and open water ponds, all of which attract various species.
The beginning of such a behemoth environmental engineering effort coincided with an agreement between the Maryland Port Administration and the Chesapeake Bay Foundation to end open water dredge disposal in Maryland, with credit to Poplar Island’s often-used “win-win” moniker, a solution which at once finds a home for the massive dredge requirements of the Port and helps restore waning Bay ecosystems in the process.
By 2007, Congress had authorized USACE to expand Poplar Island beyond its historic footprint, growing the project to over 1,700 acres and raising the existing upland habitat elevation. This expansion effort was completed in 2021, contributing to the island’s ability to accept dredge material — about 68 million cubic yards total — until it reaches capacity around 2032. But USACE isn’t finished there.
In 2023, construction began on the Mid-Chesapeake Bay Island Ecosystem Restoration Project, the successor to Poplar and the future home to over 2,000 acres of remote island habitat from across the nearly-lost James and Barren Islands of Maryland’s Dorchester County. “Mid-Bay” will provide another 30 years of placement capacity for some 95 million cubic yards of material dredged from the Port of Baltimore approach channels and tributaries, delivering again a solution to the question which remained unanswered for the first century-and-a-half of USACE’s support to Baltimore’s economic powerhouse.
Disaster strikes, solutions follow
Such recurring responsibilities for the maintenance of Bay waterways stem from the USACE authority over the country’s federal navigation channels. This authority was brought to the public’s attention with great tragedy when the Francis Scott Key Bridge, a vital transportation artery along Interstate 695, collapsed following a container ship strike.
Shortly after midnight on March 26, 2024, nearly a mile of the 80-foot-wide bridge crumbled into the 50-foot-deep Fort McHenry Federal Channel and across the ship’s bow, pinning it to the seafloor and filling the channel with 50,000 tons of debris. Within seconds, ships could no longer safely access the Port of Baltimore — and the ships docked there could not exit.
The Baltimore District Emergency Operations Center was activated within hours, enabling engineering, construction, contracting, and operations specialists from across the District and USACE enterprise to respond to the complex (and largely unprecedented) effort of reopening commerce to one of the nation’s most economically vital ports.
Using advanced imaging technologies like LiDAR, sonar, and PhoDAR — technologies typically engaged for regular channel maintenance — engineers could better understand the complexities of the submerged bridge spans. Divers with the U.S. Navy’s Supervisor of Salvage and Diving entered the cloudy waters of the Patapsco to survey the wreckage. Cranes began arriving from across the East Coast, including one known as the largest in operation in the United States at the time.
Within a month, USACE and its partners had removed enough wreckage to open a limited access channel, a 35-foot-deep section that would provide a relief valve for the ships stuck inside in the Port and allow the transit of smaller deep-draft vessels. One month later, in May, engineers had removed the wreckage that had pinned the cargo vessel inside the channel, refloating the ship and moving it to a berth at the Port.
By the first week of June, the last large truss was lifted from the shipping channel, and shortly after — only 76 days after the collapse — USACE and its partners had restored the entirety of the channel to its original dimensions, closing a new but devastating chapter in its support to the economy of the Mid-Atlantic.
Future history
Twenty thousand years ago, the Chesapeake Bay did not exist. The Susquehanna River instead flowed through a longer stretch of its own river valley, emptying into the Atlantic some miles east of the Bay’s modern mouth after traveling through the scars of a 35-million-year-old impact crater. Rising sea levels over the next several millennia — the end of the last ice age — gradually built the Bay as we now see it, slowly climbing over the capes near Norfolk and then, 3,000 years ago, reaching its present meeting point with the river at Havre de Grace.
Two hundred years ago, less than seconds in this record of geologic time, the first Army engineers began carving the way for some of the earliest maritime traffic into Baltimore, contributing to both the future and past at once. They opened waterways to commerce, they began the initial discussions of Bay health and of ecological stewardship, and they joined the rivers of the Bay’s ancient hydrography in etching a record of their presence across the region’s landscape as the Susquehanna, Potomac, Choptank, and Patapsco had long done. They do it still.
| Date Taken: | 08.27.2025 |
| Date Posted: | 12.23.2025 10:11 |
| Story ID: | 555212 |
| Location: | BALTIMORE, MARYLAND, US |
| Web Views: | 39 |
| Downloads: | 0 |
This work, In Baltimore’s Harbor and Channels, USACE Reaches from History to Hybrid Power, by Thomas Deaton, identified by DVIDS, must comply with the restrictions shown on https://www.dvidshub.net/about/copyright.
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