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Earth
Karst
Karst in the Watershed, Part 1 Karst in the WatershedPART 1: DYE TRACINGS PROVE CONNECTION BETWEEN SINKHOLES, LOSING STREAMS, AND SPRINGS; AREAS BIG SPRINGS HAVE VAST SUPPLY SYSTEMSBy Denise Henderson Vaughn, West Plains Daily Quill Correspondent Biggest Spring has Big Recharge Area
If the earth beneath us is one of the last frontiers, then Aley is the Lewis or Clark in its exploration. He made the first marks on that crude map by conducting dozens of dye tracings throughout southern Missouri during the late 1960s and early 1970s while working for the U.S. Forest Service. Aley logged hundreds of miles traveling to sinkholes and losing streams to pour in dye, and to springs big and small in search of it. He and others who explore the watery underworld start by injecting flouroscein dye into a suspected subterranean watercourse, then they go around and put their "bugs" at likely exit points. The bugs, really small dye collection packets containing activated carbon filters, are picked up later and taken to a lab for analysis. "My first big successful trace was from Hurricane Creek (in Oregon County), south of Winona, in 1969," Aley told The Quill. The dye surfaced in Big Spring on the Current River in a week, after traveling 18 miles. "It was the longest trace ever done at that time, and it got a lot of attention from the press; it was even in the New York Times Sunday paper," he said. "According to the literature, I should have used hundreds of pounds of dye. I did it with 10 pounds. That speaks to how open the conduits in the groundwater system are, with no natural cleansing." His and other dye tracings have proved that the Ozarks
groundwater flow doesn't necessarily follow the same routes as surface
water, and groundwater originating on one watershed can be "pirated" into
another river. Hurricane Creek is a dry tributary of the Eleven Point
River, so Aley's dye had to cross under the divide to the Current River
basin in order to get to Big Spring.
BIGGEST SPRING HAS BIG RECHARGE AREA While it's not recorded by Guiness, Aley said, one of his traces to Big Spring holds the current record as the longest trace in the United States, and perhaps in the world. That trace, done in 1972, originated clear over in Howell County, on the dry portion of the Eleven Point River, about two miles east of where the river valley crosses Highway 17 (between Mtn. View and Junction Hill). "It's 39-and-a-half miles, straight line," he said. It took the dye a little over three weeks to make the journey. Aley discovered much of the recharge area for Big Spring. His traces to that spring originated also on Mill Creek in Carter County (a Current River tributary), and on Jam-Up Creek near Mtn. View (a Jack's Fork River tributary), with another near-recordbreaker, a 38.1-mile trace. All those traces were done on "losing streams," which are dry creekbeds whose flow goes underground. It may be no coincidence that Aley's 1972 "longest trace" record stands unbroken. Big Spring, with an average flow of 288 million gallons per day (427 cubic feet per second), is the biggest in Missouri, and is one of the world's largest single-outlet springs. "To have a large spring, you need a large recharge area,"
Aley said. In many cases, this means robbing other areas of their surface
streams.
DISCOVERING THE DESTINATION OF A DORA DUMP Aley made the front page of The Quill on Nov. 9, 1971, when he injected dye in a heavily-used dump in a deep sinkhole on CC Highway just outside Dora, and recovered it at Hodgson Mill. "The sinkhole was along the road, easy to get to, and before that, people ignored the no-dumping signs," he said. "After the story about the trace, the dumping in the sinkhole ended; it just ended," Aley said. "This said to me, people really do care, but they need the right information. "That trace demonstrated the common uncommonly well. It's only a few miles from there to Hodgson Mill, and the dye was recovered in just less than a week." Aley relates that when he climbed down the steep clifflike sides of the Dora sinkhole to inject the dye, he found huge amounts of refuse, including piles of hardened black amorphous stuff that he didn't recognize. "I did a 'scientific study' on one; I kicked it with my boot toe, found nothing, so then I climbed on top and stomped it with my heel. Again nothing. Then I found a fresher pile. This time, when I stomped, the crust broke through and my leg went into it, deep. Then I called it by name. I drove directly to the North Fork River with my leg hanging out of the truck, repeating over and over what I'd been into." Aley had discovered the emptied insides of a septic tank cleaning truck. The 1971 Quill story said Aley also found food cans, oil cans, and once, a dead pig. No doubt this news gave pause for thought to the many area people who had enjoyed stopping by Hodgson Mill on a hot afternoon for a cold drink of fresh spring water. In that story, Aley told of a dye tracing linking a sinkhole
dump near Alton to Morgan Spring on the Eleven Point River, 15.5 miles
from the sinkhole. Morgan Spring was polluted at the time of the trace,
but soon cleared up after the dump was closed, he said.
ONE UNDERGROUND RIVER, THREE OUTLETS Like the Hurricane Creek traces, the Dora sinkhole trace also demonstrated a groundwater crossing under a watershed divide; the sinkhole is in the North Fork watershed, and Hodgson is on Bryant Creek. James Vandike, hydrogeologist with the state's Division
of Geology and Land Survey, author of a newly published 210 page book
called "Groundwater Resources of Missouri," helped delineate a new twist
to the Hodgson-North Fork connection. A trace was run in 1986, with dye
injected at the headwaters of the Gasconade River, up around Mansfield.
It had the unusual result of turning up in three springs, Hodgson, Double
and North Fork. The latter two were no surprise; they are quite close
together on the North Fork River, and an underground connection between
them had previously been established. Vandike told The Quill he received
a lab report on the water recovered at the three springs, and noticed
each water sample had an identical chemical analysis, a rare coincidence.
After ruling out lab error, Vandike looked back over past analyses, and
noticed Hodgson and Double/North Fork Springs have always had essentially
identical chemical analyses. "This strongly indicates that the springs
are separate outlets for a single karst drainage system and share a common
recharge area," he said. A rare glimpse of the underground water system to which
sinkholes can lead can be seen at Devil's Well, a steep-sided, deep sinkhole
north of Eminence near the Current River. Part of Ozark National Scenic
Riverways and open to the public, it has spiraling stairs leading down
to a cave opening in the bottom, from which a person can peer down 80
to 100 feet into a huge cavern. At the bottom can be seen a lake the size
of a football field, itself up to 100 feet deep, filling the cavern. In
the late 1950s scuba divers lowered themselves on a cable down into the
lake, then explored it, finding two other similar water-filled caverns
and a deep tubular conduit that they followed to a depth of 115 feet below
the lake surface. Although the divers couldn't get all the way to the
spring opening, dye tracings later linked the conduit to Cave Spring on
the Current River.
The Quill asked Aley, "What's left to be discovered?" He responded, "Rather than doing more studies, what's needed is to be putting our efforts into doing a better job of taking care of our water resources." "There's simple things we can do," Aley said, such as leaving a filter strip of vegetation along losing streams, just as is done on perennial streams, to control sediment and erosion. "Don't mow the hay right up to the edge, keep as wide a band of trees as you can afford." Keep livestock from beating down banks of losing streams, and don't feed them in the gravel bottoms, he added. High on Aley's list is good sewage treatment, he said.
Careful siting and maintenance of septic tanks and drain fields is essential,
and lagoons should be avoided. "In reality, we have to do a better job
than (people) in other areas. The land doesn't do the job, so we have
to do it," he said. To read more from this series, including information about other area springs, sinkholes and the West Plains water supply, see Karst in the Watershed, Part 2 Source: West Plains Daily Quill Karst Series, August/September 1998, by Denise Henderson Vaughn. Material condensed and edited for brevity. Thanks very much to the Daily Quill for permission to use this material. The Quill's four-part groundwater series ran between August 27 and September 2, 1998. The entire series, complete with maps and photos, was reprinted in a special section. Reprints are free; mail orders need to include $1 for postage and handling. |