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Inventory Review. Inventory: Menu. . = Aggregated data. . = Site Specific data. . = Aggregated data. . Inventory: General Building Stock. . = Aggregated data. . by Census Block/Tract. . *. Inventory: General Building Stock. Classifications: Distribution.
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1. HAZUS-MHUnit 3: Flood (Riverine)Hazard Analysis
3. Inventory: Menu
4. Inventory: General Building Stock
5. Inventory: General Building Stock This is an example of the distribution of the number of buildings in a typical census tract. Of all the buildings in that tract, most of them are Wood-Residential type.This is an example of the distribution of the number of buildings in a typical census tract. Of all the buildings in that tract, most of them are Wood-Residential type.
10. HAZUS-MHUnit 3: Flood Model (Riverine) Hazard Analysis
12. HAZUS Flood Hazard Model
15. Add Screen Shots for the 4 major Menu OptionsAdd Screen Shots for the 4 major Menu Options
16. Flood Hazard Model (Riverine) Step 1: Define Topography
19. Define Topography The DEM [National Elevation Dataset (NED)] can be downloaded from USGS Web site
as a seamless dataset using the default, automated functions in HAZUS
HAZUS-USGS default download: 1-Arc Second resolution (approx. 22-27 meters)
21. Define Topography
22. Flood Hazard (Riverine) ModelStep 2: Generate Stream Network
23. Step 2: Generate Stream Network User defines drainage area (to generate stream density)
Larger drainage area generates fewer, larger streams
Smaller drainage area generates more, smaller streams, but still includes the larger streams
A drainage area is the total surface area upstream [of a point on a stream] where the water flows over the ground surface and back into streams to finally reach that point
24. Based on “steepest slope”, each cell is assigned a flow directionBased on “steepest slope”, each cell is assigned a flow direction
25. Based on the flow direction, the Cell values now = the accumulation of the neighboring/upstream cells pouring into it (using 8-direction pour point model).
The cells with the largest flow accumulation values are the ones w/ the most water is flowing, hence the “stream channels”
Based on the flow direction, the Cell values now = the accumulation of the neighboring/upstream cells pouring into it (using 8-direction pour point model).
The cells with the largest flow accumulation values are the ones w/ the most water is flowing, hence the “stream channels”
26. Threshold Streams Cell values now meeting the “threshold” value (drainage area/Sq Mi. input in Step 2/Generate Stream Network) will now be used to create this dendritic pattern (our synthetic stream network)Cell values now meeting the “threshold” value (drainage area/Sq Mi. input in Step 2/Generate Stream Network) will now be used to create this dendritic pattern (our synthetic stream network)
27. Generate Stream Network
28. Flood Hazard (Riverine) ModelStep 3: Define Scenario (Study Case)
29. Step 3: Define Scenario (Study Case) Select the stream reach(es) to analyze
Reaches are sections (line segments) of streams between two nodes created by a junction from another reach
31. Flood Hazard AnalysisStep 4: Run Hydrology
32. Step 4: Run Hydrology
33. If the Reach is considered a Main Stream (originating outside of the Study Region DEM area) the flow rates/discharge are found in a pre-calculated table in HAZUS.
If #1 is not applicable, perform regression equation calculations AND make necessary adjustments if there are any gages w/ flow rate/discharge values that are applicable.
If no applicable gage data in #2, just use regression equations.If the Reach is considered a Main Stream (originating outside of the Study Region DEM area) the flow rates/discharge are found in a pre-calculated table in HAZUS.
If #1 is not applicable, perform regression equation calculations AND make necessary adjustments if there are any gages w/ flow rate/discharge values that are applicable.
If no applicable gage data in #2, just use regression equations.
34. Which process happens first? USGS Regression Equations or USGS Stream Gaga adjustment?Which process happens first? USGS Regression Equations or USGS Stream Gaga adjustment?
35. Which process happens first? USGS Regression Equations or USGS Stream Gaga adjustment?
Which process happens first? USGS Regression Equations or USGS Stream Gaga adjustment?
38. Flood Hazard (Riverine) ModelStep 5: Compute Hazard(Run Hydraulics)
39. What odes Stream Channel “morphology” mean?What odes Stream Channel “morphology” mean?
41. Delineate Floodplain(Run Hydraulics)
42. Delineate Floodplain(Run Hydraulics) Floodplain Boundary
(horizontal data)
Flood Depth Grid
(vertical data)
* Both data layers are computed w/ Spatial Analyst and output in raster format
43. Flood Hazard Model
44. Exercise 3: Flood ModelHazard Analysis