FLOOD06372

• County: Chaffee
• Community: Chaffee County
• Stream Name: Chalk Creek
• Basin: Arkansas
• Title: Flood Hazard Study, Hydrology
• Date: 8/1/1980
• Prepared For: Chaffee County
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Floodplain Report/Masterplan

1---

~-- :

I

" -'

~

Frec.
(v~s' \
~ ~ .)

2'

5

10

25
50

100.'

"---.-. --.-.. ----,

ST~P

1

h

5

6

Value
Used

;;;gTr~TION OF PRSGIPITATIOil A;VfOUl\'!'S .L7#A'LK G~-
~ HOUR PREOI?I~ATION /['<'"'-1,-'1 //r./..-40

/..~~~

/,,:1)

c: . ,~_ /)

(>1.;70

lO-DA~ PRSCIPITATION (Ref: Hy. PO-6, Rev. 2)

Estinate 2 yr., I-Hr. preci? using appropriate equation in Tbl. B-1.
2 yr., l-:-!r. in.

'1ul t i[)lJT 2yr. , 10-Day p:---8cip. by ratio in step 5 to obtain
120 yr., 10-Day preci~.
2 yr., 10-Day in X Ratio : in. (100 yr., 10-Day)
-

7 '1ultiply 2yr., 10-Day prccip. by .88 to convert to annual series.
2 yr., 10-Day _____in X .88 = in (2 yr., lO-Day Ann. Ser.)

Hap
Val1.:8

Factor

Plotted
Value

"

0.88

I /,,-"
~

8 Plott 2 yr. and 100 yr. precipe on Log-Nor~l Probability Paper
for :)ther frecuencie3.

0.96

/, p.^

0.99

/. '../-

~. d0

l.00

-
.-./.

;:'i i~

1.00

r7/-,
,-J 'f' f

d-?0

l.00

1.00

Select 2 yr., 6 and 24
2 yr., 6 Hr.
2 yr., 24 Hr.

Hr. precipe from NOAA ~p3.
in.
in.

Select ap?ropriate region from Fig. B-1.
Region .

Esti~te 2 yr., 10-Day preci? from Fig. B-2.
2 yr., 10-Day in.

Estirnate 100 yr.+2 yr., 10-Day Ratio from Fig. B-3.
100 yr.-+- 2 yr., 10-Day Ratio =