FLOOD00031

• Designation Number: 38
• County: Jefferson
• Community: Lakewood
• Title: Major Drainageway Planning - Sanderson Gulch, North Sanderson Gulch, and Weir Gulch Volume I
• Date: 8/1/1972
• Designation Date: 12/1/1974
• Floodplain - Doc Type: Floodplain Report/Masterplan

tnti~e re~ch of channel.

If the Scl~3r F~rm~ ~rC3 is ~cquired by the City of Lakcwocd for
development as a large regional park, consideration might be
given to restricting the capacity of the culvert beneath Wads-
worth Blvd. to form a more efficient reservoir routing pool
above Wadsworth. The existing plan recognizes only the reservoir
routing accomplished by the existing culvert and ponding area
and also assumes total retention of the 100 year runoff for the
tributary area above Kountze Lake.

The Eaton St. crossing is designated as a bridge with a mini-
mum deck thickness. The existing sewer in Eaton Place is
situated above the channel invert and below the high water
line. It is recommended that this sewer be relocated to a
point upstream from the Eaton St. bridge such that it is
situated in the back water pool behind the bridge. This
location will result in a minim~~ of hydraulic interference
from the crossing. The crossing should be in a steel conduit
with adequate concrete pier supports.

The Fenton St. crossing is designated as a box culvert capable
of passing the 10 year storm runoff.

The normal velocity in the channel for a major storm runoff is
e~cessive and erosion will occur. Due to the undeveloped state
of the area specific improvements are not recommended. As the
area develops, either into park lands or other type of develop-
ment, the channel should be improved by the installation of check
dams or drop structures to control velocity to acceptable limits.
Appro~imate locations for check dams are indicated on the master
planning sheet and funds allocated for future participation in
the development of this channel when development occurs.

Drawing No. Ii-a

From the match line to Harlan St. the channel flows through a
congested area of residential development. A ve~tical walled
concrete lined channel is proposed from station 214 + 20 to
216 + 75 to by-pass the residence adjacent to the gulch.
Utilities to this residence and an access bridge also cross the
gulch at this location. The costs for replacing these utilities
and the access bridge is not felt to be a public responsibility
and should be borne by the home owner. A very possible alter-
native design would be to acquire the subject house, straighten
the channel and utilize a grass lined, ),1 side sloped channel
cross section.

Drawing No. W-ll
The gulch reach across this sheet is to be totally flood plain
zoned. The gulch forms the back lot lines of houses in a large
lot residential type development. Little or no property damage
is aSSOCiated with flooding in this area as the flood plain is
totally confined to the bottom of the gulch. Significant erosion
could be e~pected during major storm occurrences in portions of
the gulch aue to high velocity flow and the unstable bank con-
ditions in several locations. The only detrimental effect of
this would be silt deposition in the Balmar Farms area as the
flow velocity decreases near the wadsworth culvert. A possible
SOlution to this problem would be construction of a sediment
detention pond somewhere on the Belm~r F~rms area to collect
sedi~ent washed out from this area for periodic removal.

A new conduit bcneath Harlan St., capable of passing a iO year
storm runoff is recommended.

West of Harlan SL the chslmel is in a flood plain zoned arc;].
with no improvements recommended.

Drawing No. W-9
The existing Pierce St. conduit shall bc left in place and the
remaining portions of this sheet flood plain zoned with no improve-
ments recommended.

A few structures such as barns and fences exist in the gulch
bottom which should be removed to prevent their being swept
downstrearr. to plug culverts. All structures within the flood
plain Should comply with the Local Flood Plain Management Policies.
Drawing No. W-12

A subdivision plat has been filed for the area in~ediately west
of Pierce street. All improvements in this area shOUld be in
compliance with the design discharges and concepts presented
in the master plan.

Drawing No. W-IO
The existing Wadsworth Blvd. culvert is more than adequate and
passes the 100 year flow beneath the road with only a minimal
uackwater. The remainder of the sheet indicates the area to
be flood plain zoned. No other improvements are recommended for
this channel reach.

A new structure ~s designed beneath Mississippi Avenue capable
of carrying the 100 year discharge bencath Mississippi. It
is necessary to have this capacity beneath Mississippi Avenue
since the backwater from this structure would totally inundate
the intersection of Mississippi Avenue and Garrison St., one
of the main intersections in Lakewood.

-lQS.

-109-