FLOOD10505

• County: Morgan
• Community: Brush
• Basin: South Platte
• Title: Brush - Storm Drainage Master Plan
• Date: 7/19/2006
• Prepared For: Brush
• Prepared By: Nolte Associates, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

, I
.1
.1

I
I
I
I
I
I
I
I
I
I
I
I
I
'I
I I
I
I
I
I

I'JOlTE

City of Brush
Storm Drainage Master Plan

BEYOND ENGINEERING

Street. Alternative 1 also includes additional retention storage volume for the Sunset Park
retention pond for the 100-year design alternative. No additional retention volume is
required for the 10-year or 25-year design altematives. It should be noted that this
retention pond was enlarged since the completion of the previous Carter Burgess study
and now has an approximate volume of7.6 acre-feet. Total estimated costs for this
alternative are approximately $0.8 million, $0.9 million and $1.1 million for the 10-year,
25-year and 100-year design options.

Alternative 2 is similar to Alternative 1 but adds a storm sewer outlet to convert the
existing Sunset Park retention facility to a detention facility (no additional detention
volume is required) and provides an outfall to a new retention facility located north of
Mill Street and east of Hospital Road. Alternative 2 is a combination of Alternatives 4
and 6 in the previous Carter Burgess study. Total estimated costs for this alternative are
approximately $1.1 million, $1.4 million and $1.7 million for the lO-year, 25-year and
100-year design options respectively.

Alternative 3 is similar to Alternative 1 and consists of construction of additional inlets
and storm sewer in Emerson Street and a larger storm sewer outfall in Cambridge Street.
Instead of discharging to the retention facility near Pettey's Gardens, the stormwater
runoff is directed to the east along Emerson Street and discharges to the Sunset Park
retention pond. With Alternative 3, the existing retention pond would require
enlargement for the 25-year and 100-year design alternatives but not the 10-year design
alternative. Total estimated costs for this altemative are approximately $0.5 million, $0.7
million and $1.2 million for the 10-year, 25-year and 100-year design options. Although
similar in cost to Alternative 1, Alternative 3 presents greater potential risk to
downstream areas in the event that the retention pond overtops. Runoffwhich overflows
the retention pond could potentially enter the Brush Lateral and overtop at undetermined
downstream locations_ With existing conditions, the tributary drainage area to the Sunset
Park retention facility is 74 acres (Basin 2 as shown on the Drainage Plan). With

Nolte Associates,Inc.

10