Q: |
How can I be assured the levee
protecting the District is actually a 500-year levee? |
A: |
Refer to Federal Emergency Management Agency
Flood (FEMA) Insurance maps covering the Earth City Levee District:
panel nos. 29189C0038H and 29189C0039H effective August 2, 1995,
superseded by a letter of Map Revisions (LOMR) dated March 5,
1996 |
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Q: |
What is the elevation at the top of the 2.6-mile levee and what
is the elevation of a 500-year flood? |
A: |
Location |
Top of Levee |
500-Year Flood |
100-Year
Flood |
| 1-70 end of levee |
462.03' |
459.03' |
455.50' |
| North end of levee |
459.34' |
452.15' |
450.55' |
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Flood levels based on 1995 Federal Emergency Management Agency
(FEMA) standard. |
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Q: |
Is it true that the major risk to the District's levee is flood
water overtopping the levee? |
A: |
No. The major risk is the undermining of the levee caused when
pressure pushes underground water into the sand layer under the
levee. This pushing action can create "voids" in the sand layer
under the levee and the weight of the levee causes the levee to
collapse into the void.
The District has addressed this risk by installing 83 relief
wells in addition to the under seepage protection berm along
the entire length of the 2.6-mile levee.
The second risk is saturation of the levee causing a collapse
of a section of the levee.
The District's levee has a heavy clay type surface up to five
feet in depth on the riverside face of the entire levee. During
four (4) major floods, no saturation problems were noted.
As for overtopping, the construction standard for a 500-year
levee requires a minimum of three feet of freeboard above the
500-year flood level. |
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Q: |
What about flood insurance? |
A: |
Federal Emergency Management Agency (FEMA) maps designate the
District as being protected from flooding by a 500-year levee.
As a result, the National Flood Insurance Program regulations do
not require the purchase of flood insurance. However, if desired,
flood insurance may be purchased. Any questions should be referred
to an insurance broker. |
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Q: |
Since the flood of 1993 was almost a 500-year flood, does that
mean the next flood is many, many years distant? |
A: |
No. There is a 0.2 percent annual chance of a 500-year flood.
It is possible, if not very probable, another major flood similar
to the 1993 event will occur much sooner than the year 2493. |
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Q: |
What is the origin of the name "Earth City"? |
A: |
The original development plan for what now is known as the "Earth
City Business Park" included office buildings, industrial
buildings, retail facilities and 4,400 apartment units which combined
would resemble a "City" with both a daytime and nighttime
population. As for "Earth" the Park's development started
in 1971 during a period when environmental terms like "Earth" were
popular. When the District was formed in 1994, the Earth City name
was adopted for the entire District. |
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