FLOOD01307

• County: Logan
• Community: Sterling
• Title: Flood Impact Study Pawnee Creek Overflows
• Date: 11/23/1997
• Prepared For: Design Technics L.L.C.
• Prepared By: ICON Engineering, Inc.
• Floodplain - Doc Type: Flood Documentation Report

I
I
I
I

~

I
I
I

,-

I
d

I

d

I
f

"i-

f

'1-

I~
r
ed

f

560.6

.p-
I:

IC-

baa. nood level Inorea.aee rleka to lICe
a.nd property. Suoh notlnca.tlon shAll
be ma.lntalned with a. record of a.ll v&ri-
ance a.ctlons u required In p&I'I.g1'a.ph
(a.){6) of this section; a.nd
(6) A community sha.ll (I) ma.lnta.ln a.
record of a.ll v&ria.nce a.ctlons, Includ-
Ing justlf'lca.tlon for their Issua.nce, And
(II) report such va.rla.nces Issued In Its
annua.l or biennia.l report submitted to
the Admlnistra.tor.
(7) Va.rla.nces ma.y be Issued by a.
community for new construction a.nd
substantia.l Improvements a.nd for
other development necessa.ry for the
conduct of a functlona.lly dependent
use provided tha.t (I) the criteria. of
pa.ra.graphs (a){l) through (a.)(4) of this
section a.re met. a.nd (II) the structure
or other development Is protected by
methods that minimize flood dama.p;es
during the bue flood and crea.te no a.d-
dltlona.l threats to public safety.
(b){l) The requirement that each
flood-prone. mudsllde (i.e.. mudflow)-
prone, a.nd flood-rela.ted erosion prone
community must adopt and submit
adequate flood plain management regu-
lations as a. condition of initia.l a.nd
continued flood insurance eligibility is
statutory and cannot be waived, a.nd
such regulations shall be a.dopted by a
community within the time periods
specified In H60.3, 60.4 or f60.5. How-
ever. certain exceptions from the
standa.rds contained In this subpa.rt
may be permitted where the Adminis-
tra.tor recognizes that, because of ex-
traordina.ry circumstances, local condi-
tions may render the application of
certa.ln standards the cause for severe
ha.rdship a.nd gross inequity for a. par-
ticula.r community. Consequently, a
community proposing the adoption of
flood plain management regula.tions
which va.ry from the standards set
forth in ~~ 60.3, 60.4, or ~ 60.5, shall ex-
plain in writing to the Administrator
the nature and extent of and the rea-
sons for the exception request and sha.ll
include sufficient supporting economic,
environmental. topographic, hydro-
logic. and other scientific and tech-
nica.l data, and data. with respect to the
impact on public safety a.nd the envi-
ronment.
(2) The Administrator shall prepa.re a.
Specia.l Environmental Cleara.nce to
determine whether the proposal for an

l

..ge

Ie
I

.. CFR 01.1 (1~1-96 Edition)

exception under puarn,ph (b)(l) or WI
section will ha.ve Ilrnlnoa.nt imp&Ct on
the human environment. The deols1on
whether an Environmenta.l Imp&Ct
Statement or other environmenta.l doc-
ument Will be prepared. will be ma.de In
accorda.nce with the procedures set out
In 44 CFR part 10. Ninety or more days
may be required for an envlronmenta.l
quality clea.ra.nce If the proposed ex-
ception will have significant Impa.ct on
the hWJ1&ll environment thereby re-
quirlnr a.n ElS.
(c) A community may propose flood
pla.ln ma.na.gement measures which
a.dopt standa.rds for floodproofed resi-
dentla.l ba.sements below the ba.se flood
level in zones Al-30, AH, AO. a.nd AE
which are not subject to tlda.1 floodlnr.
Nothwlthstandlnr the requirements of
pa.ra.gra.ph (b) of this section the Ad-
ministrator may a.pprove the proposa.l
provided that:
(l) The community has demonstra.ted
that a.rea.s of special flood ha.za.rd In
which basements will be permitted are
subject to shallow a.nd low velocity
flooding a.nd that there is a.dequa.te
flood wa.rninr time to ensure that a.ll
residents a.re notified of impending
floods. For the purposes of this pa.ra.-
graph flood characteristics must In-
clude:
(i) Flood depths tha.t are five feet or
less for developable lots tha.t are con-
tiguous to la.nd a.bove the ba.se flood
level and three feet or less for other
lots;
(ii) Flood velocities that a.re five feet
per second or less; and
(iii) Flood wa.rning times that a.re 12
hours or greater. Flood warning times
of two hours or greater may be a.p-
proved if the community demonstrates
that it has a flood wa.rning system a.nd
emergency pla.n in opera.tion that is
adequate to ensure safe evacuation of
flood plain residents.
(2) The community hu a.dopted flood
plain management meuures that re-
quire tha.t new construction and sub-
stantial improvements of residential
structures with basements In zones A1-
30. AH. AO, a.nd AE shall:
(i) Be designed a.nd built so tha.t a.ny
basement area. together with attend-
a.nt utilities a.nd sanitary facilities
below the fioodproofed design level, is

244