FLOOD00281

• County: Larimer
• Community: Greeley
• Title: Design Criteria and Construction Specifications volume 2 of 5 Storm Drainage Criteria
• Date: 10/1/1997
• Prepared For: Greeley
• Prepared By: Department of Public Works
• Floodplain - Doc Type: Educational/Technical/Reference Information

TABLE OF CONTENTS (Continued)

8.5

Allowable Street Cross..]Flow Conditions. . . . . . . . . . . . . . . . . .

8.5.1
8.5.2

Cross Street Flow at Intersections ................
Street Overtopp-i!lg ..........................

8.6
8.7

Design Example . . . . . . . . .
Checklist.. . . .. .. . . . . . . .

SECTION 9.0 CULVERTS........

9.1
9.2
9.3

9A
9.5
9.6

Introduction ......
Culvert Hydraulics
Culvert Design Standards.

9J.I Construction Mjlterial and Pioe Size .................................
9.3.2 Inlet and Outlet Configuration ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9JJ Hvdraulic Data .......................... . . . . . . . . . . . . . . . . . . . . .
9.3A Velocitv Consid.:rations ................... . . . . . . . . . . . . . . . . . . . .
9J.5 Headwater Considerations ................. . . . . . . . . . . . . . . . . . . . . .
9.3.6 Structural Desig:u ................................................

9.3.7 Trash Racks ....................................................

Culvert Sizing Criteria ...........................
Design Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 10.0 HYDRAULIC STRUCTURES. . . . . . . . . . . . . . . . . . . .

10.1 Erosion Control ........................................................
10.2 Rock Riprap Revebnent . ....... . . .......... . . . ... ......................
IOJ Energy Dissipators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
lOA Check Structures and Drop Structures. . . . . . . . . . . . . .. ......................

10.5 Bridges. . .... . ... ... ........ . . . ........... . .... . . ..... .. . . . . . . ... . . . .
10.6 Irrigation Ditch Crossings ...............................................

SECTION 11.0 DETENTION..... . . . . . . . . .

ILl
11.2
11.3

Introduction .....................................
Water Quality Enhancement. . .. .... ... .... ..... . . . . .
Storage Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

II J.I Areas Without Master Drainage Plans ..........
11.3.2 Areas With Mastc:r Drainage Plans . . . . . . . . . . . . . .
11.3J Variances..... ... ... ....... ........... . . . ..

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