Without-Project Conditions Workshop

Last Modified: 2024-08-01 19:33:56.867

Objective

Using the HEC-FDA Version 2.0 software for Workshop (in-person 75 min) – In this hands-on workshop participants use their previously generated HEC-FDA study files to perform a without-project analysis for the Muncie, Indiana example study, including the computation and evaluation of expected annual damage and average annual equivalent damage.

Downloadable Workshop Materials

Software Version

HEC-FDA pre-release Version 2.0 will be used during the 2024 PROSPECT #209 course.  (Note: the HEC-FDA Version 2.0 software is available here: FY24 Download HEC-FDA Version 2.0 Portable Package).

Note: To follow along with the instructions provided in this workshop

Unless you've already downloaded the HEC-FDA software, the Example Study Data (zipped folder contains all data needed for all HEC-FDA workshops) and the workshop datafiles then please follow the following instructions.

1. Download the HEC-FDA Version 2.0 software by following the instructions provided here: FY24 Download HEC-FDA Version 2.0 Portable Package.
2. Download and save the Workshop Datafiles to the specified path. (Note: the Example Study Data is the same data used for all HEC-FDA workshops, so you only need to download it once).

Workshop Overview

The purpose of this workshop is to have you learn how to enter data for and analyze one plan for two years (base and most likely future year). You will interpret economic and performance results using HEC-FDA.

Introduction

Review the FY24 HEC-FDA Example Study Data to familiarize yourself with the Muncie, Indiana study and download the study data.

In previous workshops, you have configured the study and entered data for the without-project base year condition. If none of the functions changed under future conditions (probability, stage-discharge, or stage-damage), we would have to evaluate only the base year conditions.  However, in this workshop, you will enter data and compute expected annual damage for the with-project, most likely future year condition.

The local planning agency has made twenty-five year growth projections of development which will alter the runoff characteristics of the basin.  Normally, predicting the runoff response in the watershed under future conditions would require us to perform all of the analyses that we did for the base year.  For example, this might entail doing the following:

• Modifying parameters in the HEC-1 or HEC-HMS model,
• Deriving new discharge-probability functions,
• Running HEC-2 or HEC-RAS using profiles corresponding to the new probability functions,
• Identifying new future structures and importing the new structure inventory, and
• Computing stage-aggregated damage using the new profiles and/or new future structure inventory.

For the purpose of this workshop, the most likely future year will be evaluated using a new future structure inventory. In the new (without-project conditions) future inventory, the number of commercial structures has been doubled to reflect an economic forecast that suggests significant growth in the concentration of commercial activity in Muncie between the base and most likely future years. 

Data Description

To save time and provide a starting point for you to build upon, a Workshop 4 HEC-FDA Version 2.0 starting project has been created for you with previously defined data (review the Previously Defined Data section for details). You will need to complete the workshop by entering the data for the without-project future year (as identified in the New Data section).

Previously Defined Data

New Data

New data must be added to the database so that you can evaluate the future condition. Data that you will enter for Workshop 4 is listed in Table 2.

Instructions

Task 1 – Open the Starting HEC-FDA Study

1. If you haven't already, download the software and workshop datafiles are listed in the Downloadable Workshop Materials section of this page.
2. Open the HEC-FDA Version 2.0 software. 
3. From the File menu, click Open. The Open Study dialog opens as a tab.
4. Click the ellipse button in the Study Path box to open the Select File browser window.
5. Navigate to the Workshop 4 starting project (e.g., C:\Workshops\FDA\startingWS\Workshop4_Start), select the *.sqlite HEC-FDA file and click Open.
6. From the Open Study tab, click OK.

Note which project elements have been entered for you in the starting workshop file. Review the Previously Define Data section for an overview of the data entered for you. Note from the New Data section, the data you will need to enter yourself to complete the workshop.

Task 2 – Import Future Without-Project Economic Data

Economic data consists of the data needed to translate the hazard into dollar-denominated consequences in the floodplain: a structure inventory and occupancy type data. This data makes up the exposure and vulnerability pieces of the consequences equation.

1. From the Study Tree, under Economics, right-click on Structure Inventories and select Import From Shapefile. The Import Structure Inventory opens as a tab.
2. From the importer enter a name in the Name box (e.g., Future_WithoutSI), and enter a description for the relationship (e.g., future without-project inventory for the without-project future conditions (In the future year, the number of commercial structures has been doubled to reflect an economic forecast suggesting significant growth in the concentration of commercial activity in Muncie, In between the base and most likely future years.)).
3. From the Structure Inventory Shapefile box select the ellipse button to open the Select File browser window.
4. Navigate to the folder containing the future structure inventory file (e.g., C:\Workshops\FDA\data\MuncieFinal\StructureInventories\future-year_without-project), select the file "BaseMuncieStructsFinalFuture.shp" and click Open.
5. The importer is a two part import wizard. From the first window select the following in the Required Attributes:
   1. Select the Ground Elevation and Foundation Height radio button. The wizard updates to provide options for defining the ground elevation.
   2. Set the Ground Elevation Source by selecting the From Structures File radio button.

   3. Make the following selections for the Import Attributes:

      Name	Import Attributes Selection
      Structure ID	TARGET_FID
      Occupancy Type	occtype
      Foundation Height	found_ht
      Ground Elevation Value	ground_elv
      Structure Value	val_struct
      Content Value	val_cont
      Vehicle Value	val_vehic
      Number Of Structures	NumStructs

   4. Click Next to access the next window in the import wizard.
6. The import wizard updates to display selection criteria for assigning the occupancy types for the structure inventory. When and HEC-FDA project contains multiple occupancy types the Load Occupancy Types from the Following Sets panel contains a list of the imported occupancy types. Only one occupancy types file has been imported for you; therefore, there is only one option to select in this panel.
7. The second import wizard window also displays the Default Occupancy Type Assignments. Review the default selections and confirm that the default selection matches the imported occupancy types. For example, RES3A should have "NSI_OccTypes MuncieOccTypes | RES3A" as the default assignment.
8. When finished reviewing the default assignments, click Finish. The import wizard closes and the imported future structure inventory displays in the Study Tree.

Task 3 – Compute Future Without-Project Aggregated Stage-Damage Functions

1. From the Study Tree, under Economics, right-click on Aggregated Stage-Damage Functions and select Create New Stage-Damage Functions. The Create New Stage-Damage Functions opens as a tab.
2. Enter a name for the new function in the Name box (e.g., Existing_Future), and enter a description for the relationship (e.g., Computed future without-project stage-damage functions for the without-project future conditions.).
3. Enter the Analysis Year: 2054
4. Select the Computed radio button and enter the information identified below (if you've been following the naming convention identified in the workshops your options should be the same).
   
5. After you complete the configuration, click Compute Curves. Wait until HEC-FDA generates the curves. Scroll through the list of computed curves (you should generate 28 curves, 16 for the Left-Bank and 12 for the Right-Bank). 
6. Click Save and the created stage-damage functions for the without-project base conditions displays in the Study Tree.

Task 4 – Create Scenarios for the Without-Project Base and Future Years

Create Without-Project Base Year Scenario

1. From the Study Tree, right-click on Scenarios and select Create New Scenario. The Create New Scenario dialog opens as a tab.
2. Enter a name for the new scenario in the Name box (e.g., Without Base Year), and enter a description (e.g., Existing conditions (without-project) base year scenario.).
3. Enter the Year: 2024
4. From the Stage-Damage list select: Existing Stage Damage.
   1. From the Left-Bank tab, select the following for the Frequency Relationship and Stage-Discharge lists:
      
   2. From the Right-Bank tab, select the following for the Frequency Relationship and Stage-Discharge lists:
      
5. The default Damage Category selection is RES and Asset Category selection is Structure. Click Preview Compute.
   
6. Click Save, and click Close.
7. From the Study Tree, right-click on the created scenario, Without Base Year, and click Compute Scenario. A message box opens asking if you'd like to view the results. Click Yes.
8. The Results for the Without Base Year scenario opens as a tab. Close the Compute Log tab.

Create Without-Project Future Year Scenario

1. From the Study Tree, right-click on Scenarios and select Create New Scenario. The Create New Scenario dialog opens as a tab.
2. Enter a name for the new scenario in the Name box (e.g., Without Future Year), and enter a description (e.g., Existing conditions (without-project) future year scenario.).
3. Enter the Year: 2054
4. From the Stage-Damage list select: Existing_Future.
   1. From the Left-Bank tab, select the following for the Frequency Relationship and Stage-Discharge lists:
      
   2. From the Right-Bank tab, select the following for the Frequency Relationship and Stage-Discharge lists:
      
5. The default Damage Category selection is RES and Asset Category selection is Structure. Click Preview Compute.
6. Click Save, and click Close.
7. From the Study Tree, right-click on the created scenario, Without Future Year, and click Compute Scenario. A message box opens asking if you'd like to view the results. Click Yes.
8. The Results for the Without Future Year scenario opens as a tab. Close the Compute Log tab.
   
   

   Alternatively

   Alternatively, you can compute all created scenarios by right-clicking the Scenarios and selecting Compute Scenarios. Once the compute is complete, click Yes to view the results and the Summary Results tab opens.

Task 5 – Create and Compute the Without-Project Alternative

Create New Without-Project Alternative

1. From the Study Tree, right-click on Alternative and select Create New Alternative. The Create New Alternative dialog opens as a tab.
2. Enter a name for the new scenario in the Name box (e.g., Without-Project Existing Conditions), and enter a description (e.g., Existing without-project conditions for the Base Year and Most Likely Future Year).
3. From the Base Year Scenario box, select the Without Base Year scenario you created in Task 4. From the Year box, enter: 2024.
4. From the Future Year Scenario box, select the Without Future Year scenario you created in Task 4. From the Year box, enter 2054.
5. Click Save. Click Close.
6. From the Study Tree, right-click on the created alternative, Without-Project Existing Conditions, and click View Results. Close the Compute Log.

Workshop Discussion Questions

For the without-project conditions, use the scenario and alternative results to answer the following questions.

Damage By Analysis Year Results

Test Your Knowledge - Question 1

For the without project, base year, which damage category has the most damage (mean expected annual damage)?

Hint: From the Study Tree, right-click Scenarios and select View Summary Results. You can also just view the results for the Base Year by unchecking the "Without Future Year" checkbox at the top of the Summary Results.

Test Your Knowledge - Question 2

For the without project, which analysis year had the greatest mean Expected Annual Damage (EAD)?

Hint: From the Study Tree, right-click Scenarios and select View Summary Results. You can also just view the results for the Base Year by unchecking the "Without Future Year" checkbox at the top of the Summary Results.

Test Your Knowledge - Question 3

How much did the future condition modifications increase total expected annual damages?

Hint: From the Study Tree, right-click on the created scenarios and select, View Results to open both the Without Base Year and Without Future Year scenarios results. Then for both results tabs select the appropriate impact area, Damage outcomes and the Damage with Uncertainty report. Then compare the mean values.

Test Your Knowledge - Question 4

For the without project, base year, what dollar amount would you expect annual damage to equal or exceed 25% of the time in the Left-Bank impact area?

Hint: For the without project base year scenario select the appropriate impact area damage with uncertainty report. Select Damage for the Outcomes and Damage with Uncertainty for the Report. On the left-hand side, we have a table with the first, second, and third quartiles of the expected annual damage distribution (EAD). Implicitly, each quartile is associated with an exceedance probability. For example, if you look at the first quartile (25th percentile) from the table, then there is a 75% chance that expected annual damage exceeds the dollar ($) value listed for the First quartile of the EAD Distribution. 

Project Performance Results

Test Your Knowledge - Question 5

For the without project, base year, what is the "Target Stage" for impact area, Left-Bank?  How is this stage determined?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results and identify the interior stage threshold. To understand how the target stage (or threshold) is determined review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual.

Test Your Knowledge - Question 6

What is the average likelihood of "significant" flooding under base year conditions in the Left-Bank impact area, if we are defining "significant" flooding as flooding that exceeds the target stage?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results for the Annual Exceedance Probability report and identify the expected annual target stage exceedance. Review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual for more information.

Test Your Knowledge - Question 7

What is the expected chance of not having "significant" flooding if the 2% chance flood occurs under base year conditions in the Left-Bank impact area?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results for the Annual Exceedance Probability report and identify the expected annual target stage exceedance. Review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual for more information.

AAEQ, Average Annual Equivalent Damage Results

Test Your Knowledge - Question 8

What is the average annual equivalent damage (AAEQ) for the without project plan for each impact area? Which impact area has the greatest AAEQ Damage?

Hint:  Open the Alternative results and view the Damage by Impact Area report. Review the Average Annual Equivalent Damage page of the HEC-FDA Version 2.0 User Manual for more information. 

Conclusion

That's it! Download the solution project (provided at the top of this page) and review the best answers to test your FDA knowledge questions and compare with yours to see how you did! You can close the HEC-FDA software when you are finished reviewing the project (click the red X at the top right to close the software).

Return to top of page.

Best Answers to Test Your FDA Knowledge Questions

Click here to review answers...

Note: Your results may not exactly match the results shown here. That's a product of variation in the software since this workshop was created and does not indicate that you did something wrong. Your results should follow the same trends and the values should be somewhat close to the ones shown below.

Test Your Knowledge - Question 1

For the without project, base year, which damage category has the most damage (mean expected annual damage)?

Hint: From the Study Tree, right-click Scenarios and select View Summary Results. You can also just view the results for the Base Year by unchecking the "Without Future Year" checkbox at the top of the Summary Results.

Answer: PUB

Test Your Knowledge - Question 2

For the without project, which analysis year has the greatest mean Expected Annual Damage (EAD)?

Hint: From the Study Tree, right-click Scenarios and select View Summary Results. You can also just view the results for the Base Year by unchecking the "Without Future Year" checkbox at the top of the Summary Results.

Answer: Without Future Year. (See image used to answer Question 1).

Test Your Knowledge - Question 3

How much did the future condition modifications increase total expected annual damages in the Left-Bank impact area?

Hint: Open both the Without Base Year and Without Future Year scenarios and select the appropriate impact area. Then for both results tabs select Damage outcomes and the Damage with Uncertainty report and compare the mean values.

Answer: For the Left-Bank impact area 2024 = $985,411.46 and 2054 = $436,072.49).

Test Your Knowledge - Question 4

For the without project, base year, what dollar amount would you expect annual damage to equal or exceed 25% of the time in the Left-Bank impact area?

Hint: For the without project base year scenario select the appropriate impact area damage with uncertainty report. Select Damage for the Outcomes and Damage with Uncertainty for the Report. On the left-hand side, we have a table with the first, second, and third quartiles of the expected annual damage distribution (EAD). Implicitly, each quartile is associated with an exceedance probability. For example, if you look at the first quartile (25th percentile) from the table, then there is a 75% chance that expected annual damage exceeds the dollar ($) value listed for the First quartile of the EAD Distribution. 

Answer: To answer the question, the third quartile (75th percentile) in the image below is $1.394 Million; therefore, there is a 25% chance that expected annual damage exceeds $1.394 Million. 

Test Your Knowledge - Question 5

For the without project, base year, what is the "Target Stage" for impact area, Left-Bank?  How is this stage determined?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results and identify the interior stage threshold. To understand how the target stage (or threshold) is determined review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual.

Answer: 944.87 feet. For impact areas without levees, the threshold (or target stage) is the stage at which 5% of the damage of the 1% event occurs. This is considered to be the stage at which significant damage begins.

Test Your Knowledge - Question 6

What is the average likelihood of "significant" flooding under base year conditions in the Left-Bank impact area, if we are defining "significant" flooding as flooding that exceeds the target stage?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results for the Annual Exceedance Probability report and identify the expected annual target stage exceedance. Review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual for more information.

Answer: 11.89%. (See image used to answer Question 5).

Test Your Knowledge - Question 7

What is the expected chance of not having "significant" flooding if the 2% chance flood occurs under base year conditions in the Left-Bank impact area?

Hint:  For the Left-Bank impact area, view the scenario results for the base year. Select the Performance results for the Annual Exceedance Probability report and identify the expected annual target stage exceedance. Review the System Performance Statistics page of the HEC-FDA Version 2.0 User Manual for more information.

Answer: 2.3%. Assurance for the 2% chance event (Frequency 0.02). 

Test Your Knowledge - Question 8

What is the average annual equivalent damage (AAEQ) for the without project plan for each impact area? Which impact area has the greatest AAEQ Damage?

Hint:  Open the Alternative results and view the Damage by Impact Area report. Review the Average Annual Equivalent Damage page of the HEC-FDA Version 2.0 User Manual for more information.

Answer: Left-Bank

Test Your Knowledge - Question 9

What is the average annual equivalent damage to the RES category for the without project condition?

Answer: $486,220.74.

Test Your Knowledge - Question 10

What project life (period of analysis) and interest rate was used to calculate the average annual equivalent damage?

Answer: A Discount Rate of 2.75% and Project Life (Period of Analysis) of 50 years. (See image provided for Questions 8 and 9.