Part G of the manual covers the design of storm drains only. It presents the design
criteria, standards, policies, and procedures to the new engineer and provides a reference
source for the experienced designer. Other office or processing operations related to
storm drain design are covered in other parts of the manual. The design of storm drains by
City forces for the Los Angeles County Flood Control District or the State Division of
Highways is not included in this manual.
G 000 INTRODUCTION
Liability and Responsibility, Project Types and Agency Jurisdictions,
Capital Improvement Projects, Assessment Projects, Private Development Projects, Easements
Watercourses, Drainage Complaints.
G 100 GENERAL DESIGN
Policy, Design Practices, Types of Drainage Systems, Excavation and
Backfill, Grading and Erosion Control, Soil Mechanics Nomenclature, Geological
Nomenclature, Preliminary Study, Hydraulic Laboratory.
G 200 HYDROLOGIC DESIGN
Rainfall Frequencies from Rain Gages, General Criteria, Surface Flow,
Peak Rate Method, Method of Summing Hydrographs, Method for Undeveloped Mountain Areas
Hydrology for Reservoirs.
ALTERNATIVE METHOD :
LOS ANGELES COUNTY
LOS ANGELES COUNTY SEDIMENTATION MANUAL
G 300 PRESSURE FLOW DESIGN
Design Procedure, Pre-Design Data, Hydrology and Alignment, Main Line
Hydraulics, Catch Basin Design, Preliminary Plans, Construction Controls, Final Plans,
Design Check Prior to Advertising for Bids.
G 400 FREE WATER SURFACE DESIGN
Geometric Design, Hydraulic Design, High Velocity Design-Sample
G 500 STORAGE BASIN AND PUMPING PLANT DESIGN
Basic Design Data, Design of Storage Plus Gravity Outflow, Design of Storage Plus Pumping.
G 600 STORM DRAIN STRUCTURES
Conduits, Standard Structures, Special Structures, Appurtenant Construction.
G 700 PLAN PREPARATION
Standards, Title Sheet, Plan and Profile Sheets, Detail Sheets, Plan
Processing and Construction.
G 800 CONSTRUCTION
Responsibilities and Relationships, Design Changes Prior to Contract,
Duties During Construction, Change Orders, Final Inspection.
G 900 CULVERT DESIGN
Criteria, Culvert Operations, Hydraulic Design, Alignment and
A. Hydraulic Properties of Streets-Office Standard No. 94
B. Design Charts for Catch Basin Openings-Office Standard No. 108
C. Hydraulic Analysis of Junctions-Office Standard No. 115
D. Hydraulic Properties of Pipe, Boxes, and Rectangular Channels-Office
Standards Nos. 116 and 117
E. Maximum Allowable Flow in Streets - Office Standard No. 118
F. Hydraulic Model Study of Bicyle-Safe Catch Basin Grates