department of public works
Floodplain Management
Every
year, flooding causes hundreds of millions of dollars worth of damage to homes
and businesses around the country. Standard homeowner and commercial property
insurance policies do not cover flood losses. So, to meet the need for this
vital coverage, the Federal
Emergency Management Agency (FEMA) administers the National Flood Insurance
Program (NFIP). The NFIP’s Community Rating System (CRS) recognizes community
efforts beyond minimum standards by reducing flood insurance premiums for the
community’s property owners.
The City of Greenville’s CRS Rating of 7 provides property owners a 15% discount
on flood insurance premiums. The following information is intended to inform you
of flood hazards in the City of Greenville and to present ways your property can
be protected against flood damage.
Flood Hazard Area
Greenville’s
main tributary is the Reedy River, which converges with Richland Creek in the
center of the city. Together, the two waterways encompass a total drainage area
of approximately 352 square miles. Due to the continued increase in urban
development along the Reedy River and its tributaries, risks have increased to
life and property during recent floods.
Current rain gage information for the City of Greenville is available through the USGS.
The rain gage is located at the Reedy River and I-85 near Mauldin Road and provides
real-time rainfall amounts. View Rain Data
The
City Floodplain Map index provides links to
maps which show the 1-percent chance floodplains. These floodplains are the area
where there is a 1-percent chance annually that a flood will equal or exceed
this limit. This is typically referred to as the 100 year floodplain. For
reference, if a structure is located in the 1-percent chance flood zone, over
the life of a 30-year mortgage there is a 26% chance that the structure will be
flooded at least once.
The 1-percent chance floodplain area is subject to dangerous flash flooding
following heavy storms. Flash flooding can occur within minutes. Therefore,
being prepared to evacuate the flood hazard area quickly is very important.
Flood hazards include quickly rising and fast moving water, which is sometimes
accompanied by logs.
FEMA Map Modernization Initiative
Special Flood Hazard Area (SFHA) maps for communities across South Carolina are
being updated as part of a map modernization program initiated by the South
Carolina Department of Natural Resources (SCDNR) and the Department of Homeland
Security's Federal Emergency Management Agency (FEMA). Please visit SCDNR and review their
Map Modernization Quick Guide or visit FEMA to learn more about this effort.
FEMA has issued a preliminary Flood Insurance Rate Map (FIRM) and Flood Insurance
Study (FIS) report reflecting proposed flood hazard determinations within the City
of Grenville, Greenville County, and other incorporated areas. These flood hazard
determinations may include the addition or modification of Base Flood Elevations
(BFEs), base flood depths, SFHA boundaries or zone designations, or the regulatory
floodway.
These flood hazard determinations are the basis for the floodplain management measures
that our community is required to adopt in order to remain qualified for participation
in the National Flood Insurance Program. However, before these preliminary determinations
are effective for floodplain management purposes, the public is provided an opportunity
to appeal the proposed information.
The statutory 90-day appeal period began on April 20, 2012. FEMA is presently soliciting
technical information or comments on the proposed flood hazard determinations shown
on the preliminary FIRM and/or FIS report for our community during this appeal period.
According to Criteria for Appeals, areas that are eligible
for appeal include:
- Areas showing new or revised BFEs or base flood depths
- Areas showing new or revised SFHA boundaries (including both increases and decreases
in the extent of the SFHA)
- Areas where there is a change in SFHA zone designation
- Areas showing new or revised regulatory floodway boundaries (including both increases
and decreases in the extent of the regulatory floodway)
The area of concern must be within the scope of the new or modified BFEs, base flood
depths, SFHA boundaries, SFHA zone designations, and/or regulatory floodway boundary
changes and be supported by scientific and/or technical data. An appeal must be
based on data that show the new or modified BFEs, base flood depths, SFHA boundaries,
SFHA zone designations, or floodways to be scientifically or technically incorrect.
All analyses and data submitted by appellants must be certified by a Registered
Professional Engineer or Licensed Land Surveyor, as appropriate. The data and documentation
that must be submitted in support of the various types of appeals are discussed
in detail in FEMA’s Criteria for Appeals.
FEMA also will consider
comments and inquiries regarding data other than the proposed flood hazard determinations
(e.g., incorrect street names, typographical errors, omissions) that are submitted
during the appeal period, and will incorporate any appropriate changes to the revised
FIRM and FIS report before they become effective. All appeals and supporting data
must be sent to:
Maria Cox Lamm, State NFIP Coordinator
South Carolina Department of Natural Resources
Flood Mitigation Program
2762 Wildlife Lane
West Columbia, SC 29172
coxm@dnr.sc.gov
803-755-9335
The preliminary FIRM data may be reviewed through the City's online mapping application,
through SCDNR's Appeals Process site, or through FEMA's Map Information eXchange.
You may also visit Floodsmart to learn more about how the Map Modernization Initiative
may impact your NFIP insurance premiums.
Map Determination
The City’s Geographic Information System (GIS) has the following Flood Insurance
Rate Map (FIRM) information:
- The parcels located in an identified special flood hazard area.
- The community number, panel number and suffix.
- The date of the FIRM and the FIRM zone.
- The base flood elevation shown on the FIRM and the elevation datum used on the
FIRM.
The City of Greenville Engineering Division also maintains information that can
provide the Best Available Information about flood risk in addition to the FEMA
Flood Insurance Rate Map information. If you have questions about your location
in relation to the floodplain, you can
find your property on the FEMA Flood Insurance Rate Map, search for your
location on the city's interactive address mapping application, or
contact the City of Greenville Engineering Division at 864-467-4400 for
assistance or to request a flood determination.
Application for Floodplain Verification Letter
Flood Warning System
The National Weather Service has developed a flood warning system for areas in
the Reedy River and Richland Creek Floodplains. A warning will be disseminated
by radio stations including WFBC, WESC, WSSL, WSPA and others. The National
Weather Service issues official weather bulletins to local and regional
television stations including WYFF,
WSPA, and FOX Carolina.
The flood warning system along the Reedy River and Richland Creek is intended to
provide up to a two hour advanced warning of a flood hazard. When an evacuation
is ordered, local television and radio stations broadcast the order. A flash
flood watch means flash flooding is possible within the watch area. A flash
flood warning means flash flooding is imminent or has been reported in the
warning area.
You can obtain additional information about evacuation, shelters and emergency
procedures by calling 911, the Fire Department at 864-467-4445 or the Police
Department at 864-467-5212.
Flood Safety
During a flood, gas, water and power lines can be
ruptured. Before leaving your property, turn off electric circuits and shut off
gas and water valves.
These simple steps can prevent additional losses due to fire, and the following
actions can help to mitigate the flood hazard during heavy rainfall:
- Monitor the level of water in streams and stay tuned to the radio or television
for possible flood waters or warnings.
- Evacuate the flood hazard area in times of impending flood or when advised to do
so by the police or fire department.
- Do not walk through flowing water. Drowning is the number one cause of flood
deaths. Currents can be deceptive; six inches of moving water can knock you off
your feet. If you walk in standing water, use a pole or stick to ensure that the
ground is still there.
- Do not drive through a flooded area. More people drown in their cars than
anywhere else. Do not drive around road barriers; the road or bridge may be
washed out. “DON’T DROWN … TURN AROUND.”
- Stay away from power lines and electrical wires. The number two flood killer
after drowning is electrocution. Electrical current can travel through water.
Report downed power lines to Duke Power at 1-800-769-3766.
- Be alert for gas leaks. Use a flashlight to inspect for damage. Don’t smoke or
use candles, lanterns, or open flames unless you know the gas has been turned
off and the area has been ventilated.
- Look out for animals, especially snakes. Small animals that have been flooded
out their homes may seek shelter in your home. Use a pole or stick to poke and
turn things over and scare away small animals.
- Keep children away from floodwaters, ditches, culverts and storm drains, and be
especially cautious at night.
Flood Insurance
Your homeowner’s insurance policy will not cover losses due to flooding. The
City of Greenville participates in the National Flood Insurance Program, which
makes flood insurance available to all city residents. If you don’t have flood
insurance, talk to your insurance agent. This insurance is backed by the Federal
government and is available to everyone, even for properties that have been
flooded.
An elevation certificate is required in order to properly rate post-FIRM buildings to purchase flood insurance. Post-FIRM buildings are buildings constructed after the publication of the first Flood Insurance Rate Map (FIRM) in a particular community. However, an elevation certificate is not required to buy flood coverage for pre-FIRM buildings unless the property owner or insurance agent wants to rate the buildings under the post-FIRM flood insurance rules to determine if the premium rate would be lower. The elevation certificate must be signed and sealed by a land surveyor, engineer or architect authorized by law to certify such information. Most elevation certificates are prepared by South Carolina licensed surveyors. The following presentation offers guidance for preparing elevation certificates.
Download Presentation
Don't wait for the next flood to buy insurance protection. There is a 30-day
waiting period before national Flood Insurance Program coverage takes effect.
Contact your insurance agent for mor e information on rates and coverage.
Some people have purchased flood insurance because it was required by the bank
when the received their mortgage or home improvement loan. Usually these
standard flood insurance policies only cover the building’s structure and not
the contents. During typical flood events in Greenville, there is usually more
damage to the furniture and contents than there is to the structure.
As of June 2007, there were 106 flood insurance policies in the City of
Greenville. If you are covered, double-check that the building coverage is
adequate and make sure you have contents coverage. REMEMBER: Even if the last
flood missed your property or you have done some flood proofing, the next flood
could be worse. Flood insurance covers all surface floods.
For general program information or inquiries about the laws, regulation or
administrative policies related to NFIP, visit
FEMA’s web site or call them at 800- 427-4661.
Property Protection
There are steps that can be taken to flood-proof structures. Some of these
include:
- Elevate the structure so floodwaters do not reach any damageable portion of the
structure.
- Construct barriers between the structure and floodwaters.
- Make structural walls and floors watertight so water does not enter (dry
flood-proofing).
- Modify the structure and relocate the contents so there is little or no damage
when floodwaters enter the building.
- Prevent sewer backups and basement flooding by installing a one-way check valve
in the sewer line.
- Elevate electrical panel boxes, furnaces, air conditioning equipment, water
heaters and laundry equipment.
There are also special flood-proofing techniques used in unusual flooding
situations, including elevation on fill and elevation on reinforced mat slabs. More information on Floodproofing.
Floodplain Development Regulations
The City of Greenville has adopted regulations and permit procedures to control
development in or adjacent to the Special Flood Hazard Areas. The regulations
require new buildings to be elevated a minimum of 2 feet above the base flood
elevation and in some cases up to 4 feet above the base flood elevation. If
additions, remodeling or repairs to an existing structure located in a special
flood hazard area equal or exceed 50% of the market value of the structure, the
structure must meet the same requirements as a new building.
Other additions, remodeling, repair, filling or excavating on the property
require a permit which must be applied for at the City’s Building Permit Office
prior to beginning any construction. For construction activities associated with
structures in or adjacent to the floodplain, the City of Greenville Engineering
Division requires an Elevation Certificate be completed and filed with the City
upon the completion of construction. All Elevation Certificates filed with the
City of Greenville are available to the public for review in determining flood
risk.
If you know of construction, filling or excavation that is taking place without
a City Permit, please report the activity to the Building Permit Office at
864-467-4550. If you know of any action that is affecting the City’s drainage
systems and is being done without a permit, please contact the Public Works
Department at 864-467-4335 or the Stormwater Management Division at
864-467-4400.
Natural and Beneficial Functions
Local and regional floodplains play a valuable role in providing natural and
beneficial functions that benefit to both human and natural systems. These
include aesthetic as well as active processes such as filtering nutrients. The
Reedy River, Richland, Laurens, and Brushy Creeks floodplains are used as a
means to filter municipal run-off. It is the riparian areas associated with
these floodplains that act as a filter and assist in filtering storm and
floodwaters so as to maintain bio-diversity and ecosystem sustainability. These
floodplains also contain historic and archeological sites that provide
opportunity for education and study. Floodplains include areas for waterfowl,
fish, and other wildlife habitats in addition to feeding and breeding grounds.
When flooding spreads out across the floodplain, its energy is dissipated, which
results in lower flood flows downstream, reduced erosion of the streambank and
channel, and deposition of sediments higher in the watershed. Poorly planned
development in the floodplain can lead to streambank erosion, loss of valuable
property, increased risk of flooding to downstream properties and degradation of
water quality.
Maintenance of Drainage Systems
The City’s Public Works Department maintains a storm drainage system throughout
the City. For the drainage system to operate efficiently, ditches, streams and
channels must be kept clean. Debris, leaves, grass clippings, tires or furniture
in ditches and streams obstruct the flow of water, cause flooding of streets and
yards, and degrade water quality.
The City’s Stormwater Ordinance and State Regulations prohibits dumping of any
material in a stream or channel and also makes it illegal to take any action
which will impede the flow of water in natural streams and waterways. If you
know of or are aware of illegal dumping or prohibited activities, please report
the activity to Stormwater Management Division at 864-467-4400. Before making
any changes to existing drainage of your property, please discuss your plans
with a representative of the City’s Stormwater Management Division.