FLOOD04373

• Designation Number: 230
• County: Boulder
• Community: Longmont
• Stream Name: St. Vrain Creek
• Basin: South Platte
• Title: Flood Control and Floodplain Management Plan for St. Vrain Creek at Longmont, Colorado
• Date: 4/1/1981
• Designation Date: 3/1/1984
• Floodplain - Doc Type: Floodplain Report/Masterplan

Wt!1,r !hsourcet; Consultants

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STUOY AREA LOCATION

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F~/NUOry, /98/

4. Review the existing hydrology prepared hy the U.S. Army Corps of
Engirreers and make recommendations to the lechr.ical Commlttee
regarding the peak flo~s for the various ff~qu~ncies. Also, pro-
vide input to the Technical Committee regarding tho year 2000
hydrology to h. dev~loped by the Corps.

5. Condu~t hydrauli~ analysis aimed at analyzing hydrauli~ st,u~tures On
St. Vrain Creek and to compute water surfa~e profiles tor the 5-, 10-,
50-, 100-, &nd 500.year frequency storms for both ~he existing and
future (year 2000) basin development ~onditions.

6,

D~linea[e the lOO-year flooded area" and present the floodway limits
on ad~inistrative ~p..

7. Prepare a drainage plan for the Boulder County Fairgrounds.

8. Id~ntify existin8, potential future flooding ptoblems, snd other ptObtern5
within the study tea~h.

9. Asaess the existing and potential flood damage.

10,

Evaluate altetnative feasibl~ plans for flood ptotection and draina~e
improv~m~nt" and ~re~~nt the sa~e to the Tech~ical Co~ittcc for the
selection of th~ tinal alternatives.

Ptepate conceptual plan., dc~igns, and project costs fot the
altetnstives and ~ke specific recommendations to the Technical
Committee regatding the posltive and negative aspects of each pL."
and the impact of each plan On the lOO-year floodplain.

Ptepate a cost/benefit cowpa.ison fot the selected plan fot i~ple~enta-
ticn after finalizing the proposed plan of imptovements.

Prepare and submit a draft of the final report for review and approval.

Ptepare the final r~pon and the ,w~eS$ary technical addendUl1l(.).

Ptesent the final teport.