A View from the Ditch: Photo set 1780. Pool 17. Copperas Creek, IL.

Early in the 1930s, Army Corps engineers recognized a significant financial and potentially legal threat to the 9-foot project. For decades up and down the Upper Mississippi floodplain cooperative drainage districts raised levees against spring floods and taxed their users to build drainage and pumping infrastructure. They operated collaboratively with the Army Corps and often relied on Corps expertise and financial largesse to mitigate flood damage - in some ways, federal conservation has its roots in moving water. But as plans for the 9-foot project progressed, the Corps had to face the fact that higher water could breach hundreds of drainage district levees. And that would be a disaster.

 

Copperas Creek is a 27-mile long waterbody that carves its way through the Rock Island County “highlands” until its confluence with the Mississippi River. Copperas Creek’s elevation drops approximately 200 feet along its run to the floodplain. Then Copperas Creek meandered. It filled backwater wetlands. It distributed rich, eroded sediment across the fertile flatland. It flooded, and then receded.

Anglo settlement along Copperas Creek began in the 1830s. Settlers farmed the floodplain without drainage or flood management until 1905 when, “the mouth of Copperas Creek … filled up (with sediment), and the backwater during heavy rains flooded the adjacent land” (63d US Congress, 2d Session, Vol. 22. 1914. p. 44). In December 1905, farmers along the creek formed the Drainage Union District No. 1 (south of Copperas Creek) and the Drury Drainage District (north of Copperas Creek). Copperas Creek was straightened from the point where the creek emerged from the hills to its outlet in the Mississippi near Blanchard Island. The channelized creek - now a ditch - had a 40 foot base. The Corps and Districts kept the channel in line with levees and routine sediment dredging. They constructed levees along the Mississippi above the Copperas Creek floodline and three feet above the high water mark of 1892 - the flood year on which the Corps of Engineers standardized all of their plans.

Plane Table Map of Copperas Creek channelization. If you look closely you can see past meander scars left in the topography before the Army Corps and the drainage district channelized Copperas.

The Copperas Creek levees were built to withstand floods three feet above the 1892 high water mark. The 9-foot project put those levees in jeopardy - it raised the water to breach-point. Nor was Copperas the only drainage in jeopardy. Drainage district officials all along the Upper Mississippi River feared future flooding and condemnation. Many threatened suit.

So the Army Corps did the only thing they could do to keep drainage districts intact - they took land along the drainage ditches, formerly creeks, through flowage easements and condemnation. They piled up the levees. They further straightened and channelized the creeks in order to move potential flood water more rapidly to the Mississippi. From the drainage district’s perspective, easements meant that the federal government had to share the cost for levee work. This story played out dozens of times along the Upper Mississippi River and indelibly connected the drainage district system to federal land management.

Take Aways:

Levee Effect: A Human Transformation and Land Use: Continuing the Agricultural Legacy - The Army Corps built the Copperas Creek levees up and high-value farmland was permitted to exist in the floodplain. North of Copperas, the Drury Drainage District is now home to 71 people. In 2019, the Army Corps assessed the value of farmland, structures, and machinery in the Drury Drainage District at $11 million. South of Copperas, the levees protect 78 people in the combined Bay Island and Subdistrict #1 of Drainage Union #1. The value of their land, structures, and equipment is estimated at $22.1 million. Photo pair 25-1780 is taken on top of the south levee, looking northerly across Copperas Creek. In front is the borrow ditch - used to supply dirt for the levee, a pathway for the ditch tender, the straightened Copperas Creek, and the north levee.

Photo set 28-1780 gives us some sense of how wide the channel is between the levees. The repeat photo gives us a clear view of how high the levees are on both sides. Note that channelization promotes erosion - which can be seen on the north bank (the right side of the photo). As that erosion continues, it will undermine the levee.

Levee Effect: An Ecological Transformation - The Army Corps took easements along most of the Copperas Creek drainage channel, which allowed farming to continue on the floodplain. Over the years, the Corps and the drainage districts have continued to modify the landscape - most notably they’ve removed nearly all of the forest and understory along this section of Copperas Creek. This was done to remove potential flooding hazards; a tree could fall in the ditch and create a logjam that would eat away at the ditch’s edge and potentially erode a levee. Clearing represents a significant loss to Copperas Creek’s ecological diversity and can impact water quality, among other things. Photo set 29-1780 is an example of this transformation.

Photo sets 34-1780 and 35-1780 are taken near the mouth of Copperas Creek - where the straightened channel empties into the Mississippi River. The creek is as straight as an arrow here and the channel is deep. Managers have planted trees on the north bank to help with stabilization. They’re not worried about a tree falling in the ditch here - we’re at the western margin of the levee and the farm fields aren’t in danger.

Historical Geography, Mississippi River, Public Land, Repeat PhotographyMatthew FocklerUpper Mississippi River, Repeat Photography, Drainage District, Public Lands, United States Army Corps, Geography, Environmental HistoryComment