Description

These tools (jupyter notebooks ) ingest data from the NOAA Hydrometeorological Design Studies Center (HDSC) and return unique, weighted excess rainfall events suitable for use in 2D hydraulic rain-on-grid models. This approach relies on:

1. Meteorological data
2. NRCS and NOAA sampling
3. Hydrologic CN loss methord

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Contents

• PrecipTable: Retrieve NOAA Atlas 14 precipitation statisics for an Area of Interest (AOI) and prepare NRCS nested hyetograph shapes to be applied to theEventsTable_Stratifiednotebook.

• EventsTable_Stratified: Calculates a stratified sample of runoff events given rainfall and maximum potential retention distributions. For each each event and corresponding return interval, the event weight, runoff value, maximum potential retention value, and rainfall value are calculated.

• _EventsTable_Traditional_Rainfall: Temporal sampling of rainfall events. For each each event and corresponding return interval, the rainfall values are calculated as hyetographs. Rainfall hyetographs and event wights are exported as JSON and DSS files. To be used for RAS 6.0 with infiltration in model.

• _EventsTable_Traditional_Runoff: Temporal sampling of runoff events. For each each event and corresponding return interval, the runoff values are calculated as hyetographs. Runoff hyetographs and event weights are exported as JSON and DSS files. To be used for RAS 5.0 with excess precipitation (runoff) applied to model.

• reEventsTable: Calculates the reduced excess rainfall given a user-specified stormwater removal rate and capacity. Given user-specified contributing areas (stormsheds), the lateral inflow hydrograhs are also calculated for each event.

• ProjectArea_HUC_Number.xlsx : Excel Workbook used to store the CN, stormwater removal rate and capacity, and information on lateral inflow domains for each pluvial domain within a pluvial model. This Workbook is called by EventsTable, PM-EventsTable, distalEventsTable, and reEventsTable.

*The (CN Method) is currently the only transform method in use for this project. Other transforms are available and can be adopted into the tool with minor modifications.

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Workflow

1. Run PrecipTable in order to calculate the area-averaged precipitation frequency table for the specified durations as well as to determine the NOAA Atlas 14 volume and region.

     Inputs:
       1. HUC code (can be HUC8, HUC10, or HUC12)
       2. Optional/as needed: 
           - Precipitation event durations; the standard  durations used is 24 hour.
   
     Outputs:
       1. A spreadsheet with the area-averaged precipitation frequency table for each duration, along with the NOAA Atlas 14 volume and region numbers.
       2. A spreadsheet with the NRCS nested hyetograph shapes.
       3. A spreadsheet with the NOAA 50% decile hyetograph shapes for each quartile (& weight of each quartile)
   

2. Run EventsTable_Traditional_Runoff in order to calculate excess rainfall events and reEventsTable to perform the stormwater reduction (optional).

     Inputs:
       1. PrecipTable.xlsx from step 1, which contains precipitation frequency tables and the NOAA Atlas 14 volume and region number. Note that the volume and region number may also be entered manually.
       2. Pluvial_Parameters.xlsx metadata file which contains the curve number and information on the stormwater infrastructure.
       4. Storm durations
       5. Filenames and paths for outputs
       6. EventsTable.ipynb
   
     Outputs:
       1. Precipitation statistics for each duration
       2. HTML copy of notebook
       3. Excess Runoff hyetographs in JSON and DSS format
   

3. Run EventsTable_Traditional_Rainfall in order to calculate rainfall events for RAS 6.

     Inputs:
       1. PrecipTable.xlsx from step 1, which contains precipitation frequency tables and the NOAA Atlas 14 volume and region number. Note that the volume and region number may also be entered manually.
       2. Pluvial_Parameters.xlsx metadata file which contains the curve number and information on the stormwater infrastructure.
       4. Storm durations
       5. Filenames and paths for outputs
       6. EventsTable.ipynb
   
     Outputs:
       1. Precipitation statistics for each duration
       2. HTML copy of notebook
       3. Rainfall hyetographs in JSON and DSS format