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Karst in Kentucky

By James S. Dinger (slides by James C. Currens)

KentuckyGeological SurveyUNIVERSITY OF KENTUCKY

McConnell Springs The Springs were named after

William McConnell who led

some fellow frontiersmen

from Pennsylvania to explore

the "Kentucky Country in 1775.

The men were camped here at

the Spring when news of the first

shots of the Revolutionary War

reached them from nearby

Fort Boonesborough.

Lexington, Kentucky, was thereby

named by these frontiersmen in honor

of the city of Lexington, Massachusetts,

where "the shots heard round the world“

were fired and the American Revolutionary War began.

What Is a Karst?

Karst is a landscape, not any single geomorphic feature

Generalized Block Diagram of Karst Terrain

Karst in Kentucky:

55 percent of the state has

potential for karst • Areas shown in dark

blue have high

potential for karst

• Areas shown in light

blue have moderate

potential for karst

• Areas shown in

yellow have limited

potential for karst

Why Are Karst Aquifers

Important?

• Large numbers of Kentucky’s rural

residents get their drinking water from

springs and wells in karst aquifers; many of

these people are farmers

• Springs contribute a significant part of the

flow to streams, which supply public water

systems

• Both underground and surface ecological

systems depend on karst aquifers

• Sensitivity of karst aquifers to

groundwater contamination

• Flooding of sinkholes

• Cover-collapse sinkholes

• Pinnacled bedrock (construction)

• Radon

Karst Geologic

Hazards

Karst Spring Polluted by Crude Oil

from a Broken Pipeline

Photograph by J.C. Currens, January 28, 2000

Groundwater Sensitivity to Pollution

• Recharge through large openings, which bypass the

filtering capability of soil

• Pollutants move through conduits with little

opportunity for filtration

• The pollutants cannot be observed and springs

become affected without warning

• Flow paths resurface at an unexpected locations

• Flow in karst aquifers is fast, allowing little time to

warn downstream water users following a reported

spill

Sinkhole Flooding

Source: Center for Cave and Karst Studies, WKU

Sinkhole Flooding Can Persist for Weeks—

Sinking Creek, Jessamine County

Photograph by J.C. Currens, February 14, 1989

Cover-Collapse Sinkhole in Boyle County

Photograph by J.C. Currens, 2001

Home Damaged by a Cover-

Collapse Sinkhole, Bullitt County, Ky.

Photograph by J.C. Currens, March 2001

Depth to

Bedrock?

Photograph by J.C. Currens, 1990

Deep? Shallow?

After Sowers, G.F., 1996,

Building on sinkholes: fig 2.6

High Radon Levels in Karst Areas

http://www.epa.gov/iaq/radon/zonemap/kentucky.htm

Building on Karst Costs More

• Higher construction cost

• Increased maintenance cost

• Human health and safety

• Environmental damage

Estimates of the Economic Cost

of Karst Hazards in Kentucky • Increased construction cost: several million??

• Property damage Minimum of $500,000/year

from cover-collapse alone is suggested by

anecdotal evidence (buildings, livestock,

vehicles)

• Sinkhole repair Maximum of $20 million/year:

$2,000 average cost, one sinkhole/square

mile/year, 10,098 mi2 in the intensively

karstified 25% of the State)

• Flooding may add an average of $500,000/year

Can these Costs Be

Avoided or Reduced?

(1) Status quo: Belief that karst-related problems cannot be avoided. Cost overruns are to be expected.

(2) Build elsewhere: Assume that for all facilities, the expense of making them structurally and environmentally safe on karst terrain is economically dubious.

(3) Build Smart: Use planning, designing, and building techniques that recognize the conditions that occur in karst.

Groundwater Dye-Tracing in the Inner

Bluegrass Karst

Photograph by J.C. Currens, January 2002

Logsdon River, Turnhole Spring Basin,

Flows through Mammoth Cave National Park

From Ray

and Currens,

1998

Mammoth Cave National Park

Completed

Recent revision

In progress

Karst Groundwater Basin Maps Status “Plate Number 1” of the Karst Atlas

TELL CITY

BEAVER

DAM

LEXINGTON

CAMPBELLS-

VILLE SOMERSET

HOPKINS-

VILLE

HARRODS-

BURG

BOWLING

GREEN

For more information on geology

and environmental issues

www.uky.edu/KGS/