1. Surface Runoff and Hydrograph Components
David Rosenberg
CEE 3430 – Engineering Hydrology
February 29, 2012

2. Today’s Learning Objectives
Describe runoff drainage patterns
Identify stream order
Sketch components of a runoff hydrograph
Compare how basin features, storm location and direction affect hydrograph properties
Compute runoff volume and infiltration rates from a hydrograph and initial abstractions
CEE 3430

3. 1. Runoff drainage patternsB.
Dendritic - uniform erosion
Rectangular – faults
Trellis on folded terrain
Trellis on mature coastal plain C. D.
CEE 3430

4. Example 1. What type of drainage pattern does the Logan River watershed exhibit?
CEE 3430

5. Basin order is the highest order branch -- at the outlet)
2. Stream Order
1 = non-branching
2 = only receive 1st order streams
Basin order is the highest order branch -- at the outlet)
CEE 3430

6. Example 2. What is the stream order of the Logan River below Beaver Creek?1 3 ??
CEE 3430

7. 3. The hydrograph (in video form)

8. 4a. Effects of basin features on the hydrograph
Slope
Roughness
Storage
CEE 3430

9. 4b. Effects of storm location and direction on the hydrograph
CEE 3430

10. Example 3. How do the Logan River hydrographs at First Dam for 2009 and 2011 differ?
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11. Example 4a. What is the volume of direct runoff (in mm) from a 120 ha catchment with a baseflow of 0.05 m3/s and the specified discharge hydrograph?
CEE 3430

12. Today we… Described runoff drainage patterns Identified stream order
Sketched components of a runoff hydrograph
Compared how basin features, storm location and direction affect hydrograph properties
Computed runoff volume and infiltration rates from a hydrograph and initial abstractions
CEE 3430