Here it is: Everything you wanted to know about the Block Hole. Or at least enough to get you to go look at it, if you've never seen it.
Larry Dowdy, executive vice president of the Little River Drainage District, is like an encyclopedia of information about the Block Hole, even when he has a busy schedule but still takes a few minutes to answer a lot of questions.
Nearly a century ago, some smart and industrious folks decided that draining the vast swamp south of Cape Girardeau would turn the area into productive farmland. So they engineered a series of canals and ditches. A key component of this project was to divert the Castor River and the Whitewater River, along with some good-sized creeks, into the Mississippi River rather than letting all that water flow into the drained area. To do this, a 90-foot-wide Diversion Channel was dug. This channel still serves its original purpose. In addition, the channel provides fishermen some great spots to try their luck at catching all kinds of fish from bass to gar to sturgeon.
When the Diversion Channel was being dug, some thought had to be given to back flow from the Mississippi during periods of high water levels. So a weir was created 11 miles west of the Mississippi where fast-moving water from the Castor River, Crooked Creek and Gizzard Creek would drop off several feet into the Diversion Channel, whose level would be determined mainly by the Mississippi.
The weir was lined with concrete blocks -- one of the sources of the name for the hole that developed at the bottom of the weir. The drop in elevation also blocked back flow and flooding to the west.
So the Block Hole was born about 1912.
While the engineers who masterminded the Diversion Channel and all the other drainage systems for Southeast Missouri produced something that still works today, they seriously miscalculated the volume of water that would flow through the Diversion Channel, which drains some 750,000 acres of mostly Ozarks woodland that stretches all the way to Fredericktown, Mo.
Over the years, erosion has widened the Diversion Channel to about 300 feet in width from its original 90 feet. The channel has never been dredged since it was built, thanks to the flushing effect of the water that goes through.
Block Hole has seen some significant changes too. What once was a weir to let water drop off into the channel is now a round hole some 450 feet wide, thanks to the natural eddy created by the water that cascades into the hole.
And it's deep too. Dowdy says the bottom of the hole is 50 to 60 feet below the natural ground level.
As a result, the Block Hole is a favorite place for fishermen who have reported catching just about every species of fish known to this part of Missouri. And some lunkers too.
Irv Landewee of the Southeast Missourian's advertising department says the Block Hole is one of his favorite places to fish because of the variety. And then he rattles off a long list of fish, which is so long I expect to hear "shark" and "whale" before Irv finishes.
Below the Block Hole, water from the Whitewater River, Hubble Creek and Cape La Croix Creek add to the Diversion Channel's flow.
If you've never been to the Block Hole, it's worth a visit. There are a couple of ways to get there.
One is through Delta, Mo. From Highway 25, go west on Route N several miles until you cross the Diversion Channel. Almost immediately you will turn right onto Route U, and about a quarter-mile later you'll turn off on a gravel lane that goes a short distance to a parking area. From the parking area you can hear the roar of the water as it drops off into the Block Hole. A short walk takes you right to the edge of the channel.
The other way to get there from Cape Girardeau is to go to Dutchtown, Mo., and take Route A west through Whitewater, Mo., to Route U. Turn left onto Route U and go several miles to where the gravel lane turns off to the left. If you reach Route N, you've gone too far.
By the way, that intersection is a major landmark for folks in the area. Route N, Route U and Route T all meet there, resulting in what's locally called the NUT Junction.
Pretty handy, huh?
By the way, I owe a special thank you to Hughes Davault of Jackson, Mo., who wrote to tell me what he knows about the Block Hole and the Diversion Channel. A couple of the interesting tidbits:
"Did you know the big main levee broke one time? It did, about two miles east of Allenville after a 10-inch rain. I think it was about 1919 or 1920.
"When they were digging the Diversion Channel, they tapped Whitewater River, and the water started running east to the Mississippi. Somebody noticed a movement in the water. It was a giant turtle. They got it out, took it up to Harry Hinton's store in Allenville, and it weighed in at 105 pounds."
Who knows what's out there in that big hole today.
R. Joe Sullivan is the editor of the Southeast Missourian.
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