Did You Know?
Mining in the Susquehanna
Given the current federal administration’s stance on coal as an energy source it’s interesting to note that the black stuff that has played such an important role in Pennsylvania’s economic history has relied on the Susquehanna River as a source for intrepid entrepreneurs who “mined” it from the river bottom. To understand this singular undertaking one needs to comprehend how coal arrived at the underbelly of the waterway that is such a significant part of Harrisburg’s landscape.
Northeast Pennsylvania has the largest deposit of anthracite coal in the world. This hard coal, as opposed to bituminous, or soft coal, has been mined and brought to the surface for over 200 years. Once brought to the surface, a substantial amount of it was washed into the Susquehanna either by natural action, like heavy rain, or from the early times when it was actually washed with stream water to remove dust. Previously, coal was actually transported via water from mines to the breaker. The breaker is a processing plant that breaks coal into various sizes and removes impurities, typically slate, from it.
The most active of these operations was located near Mauch Chunk (a.k.a. Jim Thorpe) in Carbon County where it was dumped in a creek and washed several miles downstream to a point where it was gathered and processed at the breaker. For much of the 19th Century there was little market for smaller coal sizes. Considered waste, it was dumped directly into the river. This practice made the Susquehanna and Delaware Rivers unique in North America as the only ones containing large amounts of anthracite coal. Bituminous coal, if washed into a waterway is pulverized by rolling in the bottom and eventually crushed into insignificant, albeit polluting, particles.
Anthracite is hard enough to maintain its structure and gathers in deposits where the current is slow, behind bridge piers, islands, in shallow areas and in bends in the river. Anthracite’s density causes it to deposit in piles on the river bottom separate from other rocks like shale, sandstone and gravel. This fortune rested on the bottom of the Susquehanna until an interesting shift in demand created a market for it. The emerging use of electricity in the early 1900s dictated the construction of electrical generation plants that used finer grades of coal to fire their boilers. The demand for smaller-sized coal initiated a new industry on the Susquehanna that eventually gained the somewhat euphemistic title of The Hard Coal Navy.
Operators in this enterprise built barges containing machines capable of harvesting the river coal, dredging it from the bottom where it had collected and lain dormant for so long. Although some operators existed on the Schuylkill and Lehigh Rivers, the Susquehanna accommodated the largest number of craft plying the trade. In 1919 and 1920 over two million tons of river coal was harvested each year. Harrisburg dredgers alone accounted for 400,000 tons in that time and 750,000 tons were reaped from Shamokin Creek in Northumberland County. During World War I there was an increased demand for river coal.
Gathering the coal was an exercise in production that required several types of craft. First in the process was a large boat called a “digger” that pulled a dragline in the river on the river bottom that would load a flat barge, generally 20 feet wide and sixty feet long, using a hydraulic pump. Once loaded, the barge was moved to shore by another boat called a “pusher” that was powered by a paddle wheel. Once at the shore, the barge was emptied using a loader that transferred the coal with a conveyor. From that point, the coal was sent to a processing plant where stones and other foreign materials were removed.
By the 1930s, as the process became more refined, the dredgers transitioned from draglines to centrifugal pumps that sucked the coal from the river bottom and deposited it on the awaiting barge. One can only imagine the condition of the Susquehanna and its attendant wildlife as the bottom was churned by the machines in search of coal.
This industry continued, commencing when the ice had left the river in the spring, annually until environmentalists got the Commonwealth of Pennsylvania to pass the Clean Streams Act that eventually doomed the practice of mining in the Susquehanna. An article appearing in the March 22, 1952 edition of the Pennsylvania Farmer describes the decline of the Hard Coal Navy in the Susquehanna:
Life on the Mississippi may have been more glamorous, but the North Branch of the Susquehanna which flows through the rich anthracite region of northeastern Pennsylvania has a richness of its own. On its placid bosom ply a weird assortment of river craft which sweep its bottom with huge vacuum cleaners for the precious mine waste of the great anthracite breakers. For a distance of 80 miles, from a point below Shickshinny in Luzerne County to a point opposite the State Capitol in Harrisburg, powerful dredges scour the river bottom for its treasure of ‘black diamonds.’
The ‘take’ from the river is variously estimated at from one to two million tons of coal annually, but the once-profitable business is slowly dying of starvation since the State, in 1946 passed its clear streams act. The collieries now are required to build huge desilting basins to cleanse all mine waste from the polluted mine water before releasing it into the creeks and tributaries of the river. Before the passage of this act, river men operated their rigs from early spring until December. Now they are fortunate if they can operate from the middle of April until the first of July.
The cessation of the Hard Coal Navy – the very last operator is believed to have cease operations in, believe it or not, 1996 – brings up a thought-provoking conundrum: How much coal is still in the Susquehanna River and will the recent U.S. Senate vote to repeal the Stream Protection Rule pave the way for a renewal of coal operations in the Susquehanna?
In a 1995 United States Geological Survey report (95-4122) there were sediment deposits behind three dams in the lower Susquehanna River (Safe Harbor, Holtwood and Conowingo) that included 19.7 million tons of coal. And that was in 1990. For the past 70 years, or so, the three dams have trapped much of the sediment that the Susquehanna River carries on its way to the Chesapeake Bay. The Safe Harbor Dam, built in 1931, and creating Lake Clarke, reached capacity in 1950; the Holtwood Dam, built in 1910 with its Lake Aldred, reached capacity in 1920; and the Conowingo Dam, built in 1928, with the Conowingo Reservoir behind it, has been estimated at 92 percent of its capacity but is so near its maximum capacity that a portion of the sediment is now flowing into the Chesapeake Bay.
Pamela Wood reported recently in the Baltimore Sun that Maryland Governor Larry Hogan has initiated a plan to conduct a test dredging of the sediment accumulation behind the Conowingo Dam. According to the article, “The winning bidder for the test project will be tasked with dredging a tiny fraction of the sediment that’s trapped behind the dam.
The state’s request for proposals will ask companies to dredge 25,000 cubic yards, said Roy McGrath, CEO of the Maryland Environmental Service, the independent agency that will oversee the project.
“Officials estimate there’s about 31 million cubic yards of sediment lodged behind the dam, and the U.S. Army Corps of Engineers has estimated dredging that amount would cost $3 billion,” says McGrath
With “pro-coal” rhetoric abounding, some questions come to mind: How much coal is actually there? What’s it worth on the world market? And, is it feasible to economically extract it from dredged sediment?