Drainage Design Manual, Hydrology - Flood Control District of ...

Drainage Design Manual for Maricopa County
Hydrology: List of Figures
List of Figures
1 INTRODUCTION
2 RAINFALL
Figure 2.1 Depth-Area Reduction Curve for the 6-Hour Duration Rainfall....................... 2-7
Figure 2.2 Depth-Area Reduction Curve for the 24-Hour Duration Rainfall .................... 2-9
Figure 2.3 2-hour Mass Curve for Stormwater Storage Design..................................... 2-11
Figure 2.4 6-hour Mass Curves for Maricopa County .................................................... 2-14
Figure 2.5 Area Versus Pattern Number for Maricopa County ...................................... 2-15
Figure 2.6 24-hour Mass Curve for Maricopa County (SCS Type II) ............................. 2-18
3 RATIONAL METHOD
Figure 3.1 Resistance Coefficient Kb............................................................................... 3-4
Figure 3.2 Source: Highway Hydrology (derived from FHWA, 2002) ............................ 3-11
Figure 3.3 Schematic Example Watershed ................................................................... 3-12
4 RAINFALL LOSSES
Figure 4.1 Schematic Representation of Rainfall Losses for a Uniform Intensity Rainfall4-2
Figure 4.2 Simplified Representation of Rainfall Losses ................................................. 4-4
Figure 4.3 Composite Values of PSIF and DTHETA as a Function of XKSAT.............. 4-11
Figure 4.4 Effect of Vegetation Cover on Hydraulic Conductivity .................................. 4-15
Figure 4.5 Representation of Rainfall Loss.................................................................... 4-19
5 UNIT HYDROGRAPH PROCEDURES
Figure 5.1 Conceptual Analogy of Linear Reservoir Routing........................................... 5-5
Figure 5.2 Definition Sketch of Clark Unit Hydrograph Parameters................................. 5-6
Figure 5.3 Example of Storm Hydrograph Generation................................................... 5-10
Figure 5.4 Slope Adjustment for Steep Watercourses in Natural Watersheds .............. 5-13
Figure 5.5 Resistance Coefficient Kb............................................................................. 5-16
Figure 5.6 Synthetic Time-Area Relation for Urban Watershed..................................... 5-20
Figure 5.7 Synthetic Time-Area Relation for Natural Watersheds ................................. 5-20
Figure 5.8 Example of an S-Graph from Design of Small Dams (USBR, 1987) ............ 5-23
Figure 5.9 S-Graphs for Use in Maricopa County.......................................................... 5-26
6 MULTIPLE FREQUENCY MODELING
7 CHANNEL ROUTING
8 INDIRECT METHODS
Figure 8.1 Unit Peak Discharge Relations and Envelope Curves.................................... 8-3
Figure 8.2 100-Year Peak Discharge by LP3 Analysis .................................................... 8-5
Figure 8.3 100-Year Peak Discharge by LP3 Analysis .................................................... 8-6
Figure 8.4 100-Year Peak Discharge by LP3 Analysis .................................................... 8-7
Figure 8.5 Locations of USGS Gaging Stations............................................................. 8-11
Figure 8.6 Flood Regions for Maricopa County ............................................................. 8-13
Figure 8.7 Scatter Diagram of Independent Variables for Flood Region 12 .................. 8-15
Figure 8.8 100-Year Peak Discharge Relation for Flood Region 12.............................. 8-16
Figure 8.9 100-Year Peak Discharge Relation for Flood Region 13.............................. 8-18
9 APPLICATION
Figure 9.1 Example Watershed Map ............................................................................... 9-8
August 15, 2013
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