Professional Engineering Continuing Education

P.E.C.E.  [ www.pece.biz ]

 

[NYS Approved for PE and Architect (HSW) continuing education hours]

 

Computation of storm water runoff and the DESIGN AND INSTALLATION CRITERIA FOR STORM WATER DRAINAGE LINES, CULVERTS, AND On-site storm water retention facilities (retention ponds, FACILITIES, & tile fields)

Lecturer:  Vincent A Ettari, PE

 

I. STANDARDS / CODES

 

A. Westchester County Best Management Practice Series Manual for Stormwater Management

B. Various Manufacturer Catalogues for the Types of Pipe Used in Drainage Systems

C. A Guide to Hydrologic Analysis Using SCS Methods by Richard McCuen

D. Standard Handbook of Environmental Engineering, by Robert A. Corbit

E. Seelyes Design Book

F. Various Town, Village and City Codes (Town of Newburgh, Town of Carmel, City of Rye, Town of Huntington, & Village of Oyster Bay Cove)

G. Soil Survey of Putnam & Westchester Counties, New York (by the U.S.D.A.)

 

 

II. COMPUTATION OF STORM WATER RUNOFF

 

A. Defining The Design Storm.

B. Determining the Rainfall for The Design Storm

C. Defining the Watershed / Drainage Basin from which the storm water is flowing

D. Determining the Soil Types of the Watershed (Hydrological Assignment)

E. Define the Land Uses in the Watershed.

F. Determine the Runoff Coefficient Number for the Watershed (Type II Antecedent Soil Moisture Condition)

1. Cn Number for SCS Method

2. The C Number for Rational Method.

G. Discussion of Antecedent Soil Moisture Conditions (Types I, II, & III)

H. Determining the Stormwater Runoff for The Design Storm

I. Determining the Time of Concentration, tc:

1. Velocity Method

2. Lag-Cn Method.

J. Computation of Total Runoff from the Watershed.

K. Determination of the Peak Flow from the Watershed

 

 

III. PIPE TYPES

A. Reinforced Concrete Pipe (RCP)

B. PVC

C. Corrugated Plastic Pipe

D. Corrugated Metal Pipe (CMP)

E. Corrugated Aluminum Pipe

 

 

IV. SIZING & INSTALLATION OF THE PIPES SIZES REQUIRED FOR THE SYSTEM AND FOR CULVERTS

A. Sizing of System Pipes and Culverts Using Nomographs (Figures 6-18 and 6-19 of Westchester County Manual)

B. Construction / Installation of Storm Sewers (Standard 5: pp. 6.58 6.65)

 

 

V. SIZING OF RETENTION PONDS, DRYWELLS, AND TILE FIELDS TO ACCOMMODATE THE RUNOFF FROM ROOFS

A. The C and Cn Number for Roofs.

B. Computation of Runoff from Roof for the Design Storm

1. Computing the Storage Volume Needed to Receive the Flows

2. Deep Test Holes to determine depth to Ground Water Table and Bedrock

C. Evaluation of Absorption Capacity of Soil

1. Computing the Storage Volume which has to be percolated into the ground

2. Percolation Tests to determine the absorption capacity of the soil

3. Determining the Surface Area required to percolate the water in a 24 hour time period.

Four (4) Continuing Education Hours