floodplains and flooding in louisville metro
FLOODPLAINS AND FLOODING
IN LOUISVILLE METRO
Streams and Rivers
Floodplains (subject to flooding)
Area Outside Floodplains
Approximate Area of 1937 Flood
Ohio River Floodwall
Floodwall Pumping Stations
Data provided by LOJIC and U.S. Army
Corps of Engineers. NOTE: Due to
size and printing, areas shown are
not precise. Contact MSD for
Flood watches and warnings are broadcast
on NOAA weather radio. MSD flood alerts are
broadcast on the following radio stations:
The Louisville area has been subject to flooding
for thousands of years. Low-lying land along the
Ohio River is covered frequently in the winter and
spring; flood stage is reached an average of four
times every five years.
Heavy rains cause intense flash flooding along
local streams. Large expanses of flatlands,
lowlands and former swamplands can be quick
to flood and slow to drain. And for more than
200 years, people were allowed to build homes
and businesses in our flood-prone areas.
The 1937 Flood
In 1937, the worst Ohio River flood in history
covered 60 percent of the City of Louisville and
65 square miles of Jefferson County outside the
old city. About 23,000 people were evacuated.
Damages totaled more than $1 billion in
Just eight years later, in 1945, the second-worst
Ohio River flood in history struck our community.
It drove 50,000 people from their homes, and
caused millions of dollars of damage.
The Flood Protection System
The 1937 flood prompted the construction of the
Ohio River Flood Protection System. Started in
1947, it took nearly 40 years to complete. The
floodwall stretches for 29 miles from northeastern
Louisville Metro to the extreme southwest,
protecting about 110 square miles from Ohio River
flooding. Sixteen pumping stations move
stormwater from the protected area into the river.
The system proved its worth in 1997, preventing
widespread damage during the seventh-highest
Ohio River flood in our history.
While the Ohio River floodwall system protects us
from widespread river flooding, heavy rains can
still cause devastation along local streams and in
poorly drained areas throughout our community.
The 1997 Floods
March 1997 also brought the worst local flooding
in more than 50 years. Heavy rains dropped up to
twelve inches of water in less than two days.
More than 40,000 residents suffered some kind of
flooding. All local streams overflowed their banks.
In areas away from the streams, water stood in
many highways, streets and yards, and backed up
into more than 10,000 basements.
The map above shows the land in greatest danger
of flooding today: the floodplains along our local
streams, and along the Ohio River outside the
protection system. Damage was extensive in these
areas in 1997. While a map this size can’t be
precise, you can determine if your property is in
danger of flooding by contacting MSD — in
person, by telephone, or over the Internet.
When Flooding Threatens
The Ohio River rises relatively gradually at
Louisville Metro, giving several days warning
before reaching flood stage. But heavy rainstorms
can cause local flooding in less than an hour.
The National Weather Service issues a flash flood
watch whenever forecasts show that local flooding
is possible. These watches are broadcast on
NOAA weather radio, and usually on television
and local radio stations. A flash flood warning is
issued when forecasts show that heavy, flooding
rains are definitely on the way. These warnings are
In addition, MSD issues its own flash flood
warnings over local radio stations.
When Flooding Occurs
• Stay out of the floodwater, inside and outside.
Six inches of flowing water can knock a person
down; two feet can sweep a car away. Inside
and outside, water poses a danger of fatal
• Turn off your natural gas and electricity if you
can do it without going into the water.
• Move vehicles to higher ground.
• Take your pets with you.
Reducing Flood Damage
You can help reduce flood damage on your
property and in your neighborhood.
First, keep leaves and other debris out of gutters,
drainage ditches, storm drains and gratings. Call
MSD about clogged or blocked storm drains or
If you live in a flood-prone area, MSD can give
you advice on steps you can take to stop flooding
and prevent flood damage.
Preventing New Flooding Problems
To help prevent us from repeating the mistakes of
the past, the Louisville Metro floodplain ordinance
regulates construction or any other changes in our
floodplains. MSD administers this program.
Remember to apply for a permit from MSD before
starting any repair, development, improvement or
construction in a floodplain.
WHAS AM 840
WRKA FM 103.1
WAMZ FM 97.5
WSFR FM 107.7
WFPL FM 89.3
WVEZ FM 106.9
WPTI FM 103.9
The National Flood Insurance Program provides
backing for flood insurance for any property
owner, whether the property is in a floodplain or
not. And because of MSD’s activities in floodplain
management and participation in the national
Community Rating System, property owners in
our community receive a 20 percent discount on
flood insurance premiums.
Mortgage lenders require flood insurance for
properties in a floodplain. But these policies do
not necessarily include personal property; they
may cover only the building. If you have flood
insurance, it’s a good idea to read the policy
carefully to determine what it covers, and what
If you’d like flood insurance, or would like to
increase your coverage, contact your insurance
company. You can also get information from the
National Flood Insurance Program by calling
1-800-427-5593 toll-free, or visiting the program’s
What We’re Doing
As Louisville Metro’s stormwater drainage and
flood protection agency, MSD is spending millions
of dollars to reduce local flooding and flood
damages. The measures include:
• Building stormwater detention basins along
streams throughout the area to store water
temporarily to reduce downstream flooding.
• Enforcing the stricter requirements for building
or remodeling in floodplains which were
adopted shortly after the 1997 flood.
• Erecting flood depth gauges and flood warning
signs at flood-prone areas along our streets and
roads, such as creek crossings and underpasses.
• Conducting infiltration and inflow projects
in many areas of Louisville Metro to reduce
the overload on sanitary sewer systems when
• Conducting a comprehensive drainage and
flood protection program in the Pond Creek
area, in cooperation with the U.S. Army Corps
of Engineers. The cost will total more than
$19 million, about one-fourth of it from
• Working with the U.S. Army Corps of
Engineers and local officials to fund and
construct flood protection projects in the
Beargrass Creek watershed.
MSD Can Help
MSD offers flood protection help in many ways,
MSD 24-Hour Customer Service
Floodplain Map Information
Flood Protection Information
• Offering a free video, “Lifeblood and Floods:
Our River and Streams,” describing the local
flooding problem and how to cope with it. To
obtain a copy, call 540-6204.
Basement Backup Prevention
To report drainage problems,
illegal dumping or construction
activity in floodplain
• Making detailed floodplain maps available
showing every property in Louisville Metro,
along with its history of flooding. These maps
can be viewed at MSD’s main office during
normal office hours.
Federal Flood Insurance
• Visiting a property to review its flooding
• Offering backflow valve programs to qualified
homeowners to prevent sewage from backing up
through basement floor drains.
• Providing free advice on measures property
owners can take to reduce damage from surface
• Offering information on selecting a qualified
contractor to install flood protection devices.
LOJIC (interactive maps)