FLOOD10386

• County: Jefferson
• Community: Golden, Lakewood
• Stream Name: Upper Lena Gulch
• Basin: South Platte
• Title: FHAD - Upper Lena Gulch
• Date: 1/1/1993
• Prepared For: UDFCD
• Prepared By: Boyle Engineering Corporation
• Floodplain - Doc Type: Floodplain Report/Masterplan

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15

to

10

Over the last

Lena Gulch

kept for

records were not

flood

thorough

recently

Unti

Office Park

West

upstream of the Denver

tributaries just

View and Green Mountain

the Pleasant

I

this basin has

flooding in

monitoring

recording and

to

attention paid

the level of

years

1-70 and into a series of ponds in

-70. The drainageway passes through box culverts under

and

flow

has installed automated

The Urban Drainage and Flood Control District

ncreased

West, the channel

Denver

Downstream of

Office Park

West

portion of the Denver

the lower

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flood

"ALERT'

its

this basin into

n Lena Gulch and has incorporated

detection eqUipment

then under

residential areas and

mproved sections and meanders through

consists of various

forecasting network

it

is unimproved and

Youngfield Street it

Downstream of

nto Lakewood

Y oungfield Street

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mproved crossing under

recently

to a

residential properties

through

continues downstream

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the frequency or severity of flooding in the upper

ittle Information was compiled on

Historically

20th Avenue and into Maple Grove Reservoir at the downstream end of the study area.

frequency flood events have caused a number of

is known that relatively high

it

basin. although

I

the basin

1980 caused numerous damages in

May 5

on

flood event

A

flood problems

History

I

was

for that event

flow

The estimated

reaches above Maple Grove Reservoir.

the

especially In

of the 2-year flood

little more than half

a

second (cfs)

per

approximately 430 cubic feet

View area of Jefferson

the Pleasant

940's in

the early

in

began in earnest

Basin development

I

n both commercial and

the basin has seen continued growth

the years

Over

County

overtopping 20th Avenue by 3

reportedly had water

flooding occurred which

1987

On June 8

the upper

in

Mobile Premix Quarry

ocation of the

The present

residential development.

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to 2 feet.

1

ponds by

West

the dam crests of the Denver

overtopping

feet and had water

to 4

for the dam at Chatfield Reservoir.

to provide rock

was originally opened

portion of the basin

I

which is slightly

Alkire Street

600 cfs measured at

was about

flow for this event

The estimated

park and shopping complex at

an amusement

the construction of

Apex Gulch has seen

than the 2-year flood

less

The commercial developments along U.S. Highway 40 upstream of

Heritage Square in Golden

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residential

Numerous

the basin

portion of

this

from

runoff

ncreased

6th Avenue have

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Lena Gulch at

the basin

flooding In

caused considerable

1991

on June

event

Another

Park in Jefferson County and

the Mountain Side Mobile Estates Trailer

developments such as

residential

the nearby

of

into and out

blocking access

overtopped

was

Street

sabe

the Applewood Hills and Applewood Glen areas upstream of 20th Avenue In Lakewood have

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subdivision

runoff.

thereby Increased storm

the basin and

mpervious areas in

of

increased the amount

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from

damage

deal of

a great

for

that the potential

the story clearly

tel

events

These past

over the years

Lena Gulch has also been changed by development

Upper

The historic path of

I

this baSin

flooding exists in

the location and capacity

the area.

of runoff from

Office Park along Interstate 70 modified both

Lena Gulch channel. and increased the amount

West

The large Denver

of the Upper

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