FLOOD00122

• County: Boulder
• Community: Longmont
• Stream Name: Dry Creek
• Title: Floodplain Information Report
• Date: 4/1/1980
• Prepared For: Boulder County
• Prepared By: WRC Engineering, Inc.
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

CIlAPTERI
INTRODUCTION

Therefore, upon official approval of this report by the Colorado
Water Conservation Board, the areas described as being within the
lOO-year flood (IX chan~e flood)* Can be designated a~ flood hazard
areas and their use regulated accordingly by the Local agencies.

A. Authorization

This study was authorized by Boulder County in cooperation with the
City of Longmont and the Colorado Water Conservation Board. Specific
tasks were performed according to the terms of the contract dated October
10, 1979, between Boulder County and Water Resources Consultants, Inc.

" , . . to utabLU.h, .tegu.la.te, lIe-6Vt-ic.t, Md t.(mu -I>Uc.h
u..\U 011 M al_ollg I1.WJ -6.toJwr o.t ~toodwc:ttv! l!u.no~~ c.haJtnet Oil
b<wbt, M ~h -6.to1lm M ~loodl"lltH .tu.no~~ c.h<1ltllu OJ! bw.,J.n
hiM been del.>-igM..ted and a.ppltove.d by the. Colollado w<ttvt: COIl-
I.>e.l!Va.UOII 80M.d, J.n IIl!dM to ll!h-6e.1l Ill! a.vo-id the h<U:M.dl.> to
peAl.>olt.!.> aM dll/lldge to ptopeAty I!e.w.tting ~.tom the. ~CUl7lUta-
uon o~ I.>tOJ!m OJ! Moodwa.te.M . , , "

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B. Purpose and Scope

The purpose of this .tudy lS to determine the potential area of
flooding along Dry Creek No.1 and to recommend a feasibie and practical
plan for control of flooding in the reach within the City of Longmont.
The specific location of the study reach is ShOwn in Figure-I. The
floodplain information provided in this report will be used by the
county and local agencies to regulate the land uSe of areas within the
floodplain and thus reduce future damages. Implementation of the
recommended plan for drainage improvements for the study reach in the
City of Longmont will further reduce damages to existing populated

The cities, incorporated towns, and counties within the study area
may provide zoning regulations:

ar"AS.

as stat"d in Section 30-28-111 for the county governments and Section 31-
23-210 fnr municipal governments of the Colorado Revised Statutes 1973.

The soupe of the study includes the followin~ items:

The Colorado Water Conservation Board has the power and duty:

1. Meet with representatives of Soulder County, the City of Longmont,
the Colorado Water Conservation Board and other public and private
agencies for basic information and data collection.

" . , . to dcv<<e and 6oll.mu1a.te mcthoM., mC<lll4 Md p.t'(Ul.6
6M b.ting-ill.g about thc gll.ea.teJ! u.uUza.Uon o~ the ~I.> o~
the. -6.to.te. and the ~evenuOll. 06 6tood damagu tite..te~l!Om and
to dw.i.gMte aM appltove Moltm 011. 6loodway .tun06 ~ C.MnI1CU
Ill! ba./lw, aM to make 6U.c.h du.i.gna.ti.oM avMla.blc.to leg<<-
ta.Uve. bodiM o~ cU.i.w and unineOll.pOll.atc.d.towlt-6; to county
pt1.nn-ing CO~OIt.!.>; and.to bOMd-6 o~ adju..\tmenM o~ citLe~;
-t11c.oltpoJt<loted~; MJ C.O'iIlUW o~ th.i..6 M4te , . . "

2. Conduct the necessary field investigations.

3. Document the flood history.

as stated in Section 31-60-106(1)(c) of the Colorado Revised Statutes 1973.

* The term "l~ Chance Flood," "Intermediate Regional Flood," and "IOO-'(ear
Freqlleney Flood" can bo used interchanKeablyas they are defined b ythe
Same type of flood event (see Glossary). Hnw~v~r, for consi.teney. where-
ever possible, the term "IOO-Yeat Flood" will be used in this report.

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