FLOOD09306

• Designation Number: 204
• County: Larimer
• Community: Fort Collins
• Stream Name: Spring Creek
• Basin: South Platte
• Title: Major Drainageway Planning - Spring Creek, Fort Collins, Larimer County, Colorado
• Date: 8/1/1980
• Designation Date: 1/1/1983
• Floodplain - Doc Type: Floodplain Report/Masterplan

Group C - A grass-lined channel is requiN!G upstream of Shields Street to
convey the lOO-year discharge. The Larimer County HZ Canal. the New
t~ercC! r Cana 1, an d the Pl cas an t Vall ey and La ke Cand 1 were ro ute d
through siphons under Spring Creek. Floodproofingwa,t€quii'edat
the Georgetown Condominiur.lS upstream of Drake Road, while a grass-
lineuchannel was designed upstt€df;l of Taft Iii 11 Road along with a
roadway pan at a crossing approximately 800' upstrear~ of Orake Road.
Design discharges through these t€aches ranged from 1600 cfs to 3100

GroupB-rlfliJrovementsbetweenLeM.;yAvenuedlldCol1egl:Avenul:Hetllesd<ll:

as forAlternative!i2, except for utilizing a grass-lined channel in-
stead of concrete. A grass-lined channel was also designed through
the Spring Court Mobile Home Park upstream of College Avenue to the
Colorado & Southern Railroad. A berm is required along Sneely Street,
and an improved canal crossing at Arthur's Ditch. Thedesigndis-
charges in these reaches variedfromlg50cfsto3000cfs.

cfs.

Group C - Improvements in these reaches include clearing of vegetation in the
channel upstream of Shields Streetwlth siphons placed at all canal
crossings. FloodproofingisrequiredattheFoothillsApartments
upstream ofSI,ields Street and at the Geor<;letown Condominiums up-
stream of Drake Road. A grass-lined channel is required downstream
of U'e Pleasant Valley and lake Canal. An improved culvert is
required under Drake Road. Design discharges through these reaches
rallged from 1600 cfs to 2~OO ds.

Alternative #3
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The lOO-year flood event with full basin development and existing de tentianatTaft
Hill Road and the Colorado ~ Southern Railroad west of College Avenue was the design
flow for this improvement alternative. The inadvertent detention behind these two em-
bankments is very significant in reducing flood peaks (Figure 4) andhencet he cost
of improvements downstream. The existing detention at the Colorado & Southern Rail-
road near Timberline Road contributes to theflooddamag€potentia 1 in this reach
ancl has minjmal effects on peak flows downstream and isthereforeeli minated in this

Alternative #4

Group A

Improvements in these reaches include berms upstream and downstream of
the Colorado "'Southern Railroad near Timberline Road on the South

Ih' s 0.1 ternatlve IIg<lln uses the IIJO~year event for tully developed basin conditlOns
as the design flow. The alternative, however, considers a major det"ntion facilit y
at Moore Park in place of existing detention at Taft Hill Road and the Colorado ~
Southern Railroad flear College Avenue. This alternative was selected to provide
the benefits of reduced peak discharges from detention without tneuncertainties

alternative.

bankofSpringCreek,and300' upstream of LeMay Avenue. An improved

grass-lined channel was designed downstrf'anrofStOVl'rStrf'-I't. Im-

for safety and for preservatlon ofexistingdetf'nti011 areas.

provedculvertcrossingsarerequiredatTimberlineRoad,thcColorado
& Southern Railroad,and300' upstream of LeMay Avenue at apriva te

GroupA&B-lmprovements throughout these N'aches are simildrto those for
Alternative #2. Beros,Culvcrtcrossingsandimprovedchannelsare

driveway. Design dischdrges through these reaches ranged froITI2aOO

smaller due to a decrease in design discharges.

cfs to 2400 cfs.

Group C - Improvements for the,e reaches are the same as for ,~1tern~tive n

except for the additiofl of tlicMoore Park detention area upstrea .."

of Shields Street.

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