FLOOD05477

• County: Boulder
• County: Weld
• Community: Erie
• Stream Name: Coal Creek
• Basin: South Platte
• Title: Proposal/Feasibility Study for Flood Control and Floodplain Management Plan for Coal Creek
• Date: 8/1/1979
• Prepared For: CWCB
• Prepared By: WRC Engineering, Inc.
• Floodplain - Doc Type: Miscellaneous

I

I

I

4. INFLOW/OUTFLOW PEAK FLOWS FOR WANEKA RESERVOIR

Client(s): City of Lafayette, Colorado

I

I

WRC collected the basic hydrologic data and developed the peak inflow

hydrograph and the resulting peak outflow for the Waneka Reservoir. Two

separate methods were used to compute the inflow design hydrograph: First,

the use of the Probable Maximum Precipitation (PMP) resulting from a gener-

al storm; second, the use of the SCS Triangular Hydrograph method for a

thunderstorm event. The resulting peak outflow was computed by routing the

inflow hydro graph through the reservoir. The results of the study were used

to determine the spillway adequacy and the need for dam rehabilitation features.

I

I

I

5. WESTVIEW SCHOOL CULVERT

I

Client(s): City of Northglenn, Colorado

I

WRC provided complete planning and design services for
, .

diameter reinforced concrete pipe culvert. Specific tasks

design of the inlet structure and two transition sections;

concrete; foundation design; erosion control design; and

construction drawings, specifications, and bid documents.

a 950 foot-long 60"
included hydraulic
design of reinforced
preparation of

I

I

6. HYDRAULIC ANALYSIS OF NORTHRIDGE SHOPPING CENTER CULVERTS

I

Client(s): Faulkner-Kellogg & Associates

I

Responsibilities included calculations of the 100-year frequency flow and

computation of the energy grade line, hydraulic grade line, and water surface

elevation for the flow as it passes through a series of different size culverts

and open channel sections. A total of fifteen different type of losses were

computed. Control sections for the culverts were determined and their impact

on the carrying capacity of the culverts was analyzed. Culvert sizes ranged

from an 8' x 6' single barrel to a 10' x 6' double barrel. Culverts were

connected in a series via transition sections.

I

I

I

I

I

-8-