specialized gis skills at the swfwmd part 4: arcgis 202 – hydraulic element points

Hydraulic Element Points in ArcHydro

Specialized GIS Skills at the SWFWMDPart 4: ArcGIS 202 – Hydraulic Element Points


What is a “Hydraulic Element Point (HEP)”?ArcHydro constructs a generalized, natural HydroNetwork consisting:

- HydroJunction(s): points connected by- HydroEdge(s)

This “generalized” network shows the surface flow direction but does not include any detailsregarding the “elements” (structures) comprising those Junctions and Edges


What is a “Hydraulic Element Point (HEP)”?In the language of GWIS/ArcHydro, a HEP is a point that contains the detailed description of the hydraulic element (structure).

Hydraulic Elements include objects such as:- the ends of a pipe (end treatments)- each element comprising a water control structure- a weir- a bridge deck, a bridge opening, or a bridge pier- etc.


Steps in Collecting Hydraulic Element Points – Overview 1 - Setup

1- Create a workspace (directory) on your local drive.2- Use ArcCatalog to COPY the HEP Geodatabase to your directory.3- Use ArcCatalog to RENAME the HEP Geodatabase to: WATERSHED_HEP4- Start a new ArcMap session with the following items in the TOC:

a) Digital Elevation Model (DEM) for the watershed b) Recent or appropriate imagery (use an image service where possible)c) Georeferenced plansd) The following feature classes from the WATERSHED_HEP Database:

-HYDROJUNCTION-HYDROEDGE-HEP_LINE-HYDRAULIC_ELEMENT_POINT

5- SAVE the ArcMap .MXD as WATERSHED_HEP.MXD (The name of the .MXD MUSTbe the same as the GWIS database for the tables to synchronize.)

When starting a NEW Watershed:


Steps in Collecting Hydraulic Element Points – Overview 2 - Collection To Collect/Edit HEPs from an ERP:

1- Add the georeferenced ERP sheet to the WATERSHED_HEP.mxd2- Open supplementary detailed plan sheets (as needed)3- Start Editing on the HYDROJUNCTION and HYDROEDGE feature classes4- Collect the HydroNetwork first: HydroJunction(s) and HydroEdge(s).

NOTE: We advise studying the collection system as they usually occur in discrete sections. Familiarize yourself with a section so that you understand how the system works, finding the inlets, outfalls, structures, and connectivity, unseen pipes, and below surface connections.REMEMBER TO SAVE OFTEN!!

5- Stop Editing and SAVE the HydroNetwork 6- Collect the HEPs for the collection system.

(You do not need to open an Editing session.)7- Identify another collection system and repeat 3 – 68- Repeat until complete ERP has been collected9- Save your MXD and edits incrementally and when completed with an ERP.

NOTE: Remember that you SHOULD be collecting HEPs from the most recent ERP revision. Check for earlier revisions that may contain additional HEP information


Collecting Hydraulic Element Points – DetailsInitial Setup

Copy the HEP Geodatabase to your directoryUse ArcCatalog to make sure that the fGDB is named correctly (Watershedname_HEP.gdb)Start (or open) an ArcMap with the following layers:

- Recent/appropriate imagery- The county-wide DEM for the watershed- The following layers from the WATERSHED_HEP GDB

HydroNetwork:HYDROEDGEHYDROJUNCTION

Watershed:HEP_LINEHYDRAULIC_ELEMENT_POINT

Notes:

1- You can add any tables to the MXD to check that features are being added correctly.

2- DO NOT rename any of the Feature Classes


Initial Setup, con’t.Save the MXD as:

WATERSHED_HEP.mxd.

NOTE: It is VERY important that the name of the MXD and the fGDB are the same. Otherwise the HEPs will not be synchronized in the database tables.


Initial Setup, con’t.

Add the georeferenced ERP to the ArcMap document

HINT: You might want to turn on the “EFFECTS” tool to SWIPE the ERPand/or adjust the TRANSPARENCY of the ERP


Collect the HydroNetwork

Study the ERP plan and identify/isolate a specific portion of the collection system.You may need to reference the original PDF


Collect the HydroNetwork, con’t.

Start editing the HYDROJUNCTION Feature Class (right-click in TOC)

Choose the Point feature to edit



Collect the HYDROJUNCTIONS (I also changed the symbol)



The values are of the form: ERP_XXXXXX.XXX_### where XXXXXX.XXX is the ERP Number and ### is a 3-digit sub-element number (including leading 0s)

The HYDROCODE_DESC field is found in both the HYDROJUNCTION and HYDROEDGEtables. It is used to track these features through the ArcHydro database. It is alsoused to identify these features on an ERP-by-ERP basis.

Because this value will be used as an ERP-specific value, the operator MUST manuallyinput and increment it.

YOU will need to Type (or Copy/Paste) the HYDROCODE_DESC for each HYDROJUNCTION and each HYDROEDGE that you enter. You will also need to add the ERP number (minusthe ### for any General HEP Points by manually editing the HYDRAULIC_ELEMENT_POINTTable.

The following slides illustrate the preferred workflow.


Collect the HydroNetwork, con’t. – Recommended Workflow

1- Right click on HYDROJUNCTION and scroll to Edit Features

2- Select the HYDROJUNCTIONfor editing



3- On the Editor Toolbar, use the Attributes Button to edit the fields

4- Edit the HYDROCODE_DESCField (ERP_XXXXXX.XXX_###), thenCopy that entry (Ctrl-C)

5- Use the dropdowns to select valuefor theHYDRAULIC_TYPE_DESCRIPTION

6- Capture the next HYDROJUNCTION,and,

7- Paste the HYDROCODE_DESCand increment the ### by 1

8- CHECK the HYDROID to make surethat it is incrementing as you addfeatures.

9- Capture all the HYDROJUNCTIONSfor the collection subsystem.


9- Activate the HYDROEDGE Feature Class and choose the Line construction tool

10- Activate the SNAPPING Tool and choose NODE



11- Digitize the HYDROEDGE

12- Paste/Update the HYDROCODE_DESC


NOTE: The FLOW_DIRECTION_DESC, HYDROEDGE_TYPE_DESC,HYDROEDGE_PLACEMENT_DESC, HYDROEDGE_HYDRAULIC_TYPE_DESC,And INCLUDECONNECT_DESC will auto-populate.


13- Complete collecting the HYDROEDGEs, and 14- Save your edits.

(Remember, it is a good idea to save your edits incrementally as you are working!)

You have now collected the HydroNetwork. On to HEPs …



Collect the HydroNetwork – Alternative Workflow

1- Collect ALL the HYDROJUNCTIONS and HYDROEDGES in the subsystem2- Open the HYDROJUNCTION table (with edit session still open)3- Edit (Copy/Paste/Update) the HYDROCODE_DESC field4- Repeat for the HYDROEDGE table


Collect the HydroNetwork – Continued Workflow

It is VERY important that the HYDROCODE_DESC value remain unique. Some ERPsmay require several sessions over several days to complete. So, when returning tocontinue the HydroNetwork collection, you should:

1- Open BOTH the HYDROJUNCTION and HYDROEDGE tables,2- Sort (right-click on the field header) the HYDROCODE_DESC field, and3- Record the highest numeric value to increment for your next HYDROCODE_DESC


Check/Assign the HydroIDsArcHydro works by maintaining a unique HydroID for each and every feature. When you heads-up digitize features, HydroIDs should be assigned sequentially. This SHOULD happen automatically,BUT it is always a good idea to check. Open the HYDROJUNCTION and HYDROEDGE tables to check.

IF there are negative HydroIDs, use the Attribute Tools Dropdown Menu and select Assign HydroID


Check/Assign the HydroIDs

Check that the HydroIDs have been assigned correctly by opening the HYDROEDGE and HYDROJUNCTION tables

You are now ready to collect the HEPs !


Setup and Collecting HEPs

Activate the SWFWMD Connectivity Toolbar and select the type of HEP you are going to capture

REMEMBER: HEPs (except General Points) are associated to the HydroNetwork, so…

- Pipes (and Barrels) are associated with HYDROEDGES- Weirs are associated with HYDROJUNCTIONS- Bridge Decks, Openings and Piers are associated with HYDROJUNCTIONS- General Points are not associated with the HydroNetwork


Collecting HEPs

When first starting to collect Hydraulic Element Points, the cursor will turn into a crosshair and when you click on the FIRST point to capture, you will get aDialog box…

Use the Down Arrows to navigate to the Countywide DEM that you are usingand make SURE that the correct Feature Classes are selected for each of theadditional specified Feature Class destinations.


Collecting HEPs

If you click on a HEP point, you WILL SEE this error message…

because FIRST you MUST select either a HYDROEDGE or HYDROJUNCTIONwith which to associate the HEP (except for General Points).

- Pipes (and Barrels) are associated with HYDROEDGES- Weirs and Control Structures are associated with HYDROJUNCTIONS- Bridge Decks, Openings, and Piers are associated with HYDROJUNCTIONS- General Points are not associated with the HydroNetwork

Use the ArcGIS “Select Tool” to graphically select the appropriate HydroNetwork element


Collecting HEPs – PipesWith the HydroNetwork Element(s) selected and Pipe chosen, click the UPSTREAM end, fill in the table, then click the DOWNSTREAM end and fill in the table to complete the Pipe.

The Connectivity Tool will estimate the elevation from the DEM, but YOU are expected to review the plan and INPUT the ACTUAL elevation and other detail information!

Once the HEPs (Upstream/Downstream) are captured, the ArcHydro will construct the HEP_LINE representing the actual pipe (green line in the figure below). You do not digitize the HEP_line!


Collecting HEPs – Pipes

Table after clicking up-stream elementwith elevation from the DEM. Notice thatthe HYDROCODE_DESC was transferred fromthe selected HydroEdge!

Table after editing the elevation from the plan set

NOTE: Gray fields CANNOT be edited

Repeat for the downstream element editing the ELEMENTZ field


Collecting HEPs – Pipes

When the Upstream & Downstream elements are defined, the SubElement Table – Pipe will appearThe gray fields still cannot be edited; YOU need to fill in the non-gray fields. Several can bepopulated from the database domains; others are manually edited (when possible) using plan details.

Notice: (1) New HydroIDs have been assigned and (2) the HYDROCODE_DESC of the HydroEdge has been retained


Things To Watch For When Collecting HEPs – Pipes

Pipes/Culverts going under roads are represented by a single HYDROEDGE with HYDROJUNCTIONS at the ends

Pipe HEPs are related to the HYDROEDGEA Subelement Index Count is assigned to each pair of HEPs

HydroJunction(Inlet/Outlet)

HydroJunction(Inlet/Outlet)

HydroEdge(Pipe)

HEP[UIC - SubElement 1]

HEP[UIC – SubElement 2]

HEP[DIC - SubElement 1]

HEP[DIC – SubElement 2]


Things To Watch For When Collecting HEPs - Structures

HEP

HEP

HEP

HEP

HYDROJUNCTION

One HYDROJUNCTION (the structure) with two HEPs (horizontal and vertical weirs) plusthe two(2) HEPs related to the HYDROEDGE for the Pipe!


Collecting HEPs – General Points

General Points include elements such as; Ground Elevations, Top of Road, Channel Banks,and others. To capture a General Point:

Select General Point from the Drop DownClick on the MapUse the Domain Field to choose the General Point Type


Collecting HEPs – General Points, con’t.

Click on the POINT_TYPE_DESC to show the types of points available in the Domain and select the appropriate type

The ELEMENTZ files will self-populate from the DEM; Adjust the elevation to the plan set elevation. Press “OK” and continue collecting HEPs


Collecting HEPs – General Points, con’t.

GENERAL POINTS require the operator to manually enter the HYDROCODE_DESC, butbecause these points are NOT associated with the HydroNetwork, they are NOTassigned a numeric extension.

After GENERAL POINTS are collected, the operator should open the HYDRAULIC_ELEMENT_POINT table and calculate the HYDROCODE_DESC fieldto the ERP Number (ERP_XXXXXX.XXX) as in the example below.


Collecting HEPs – General Points, con’t.To populate the HYDROCODE_DESC field for GENERAL POINTS,

- Select the points (Shift- or CTRL-click to select multiple points)- Right-click on the HYDROCODE_DESC heading and choose the

Field Calculator- Enter “ERP_XXXXXX.XXX” into the dialog window (quotes are needed)- Press OK to calculate- Close the table

Dialog Window


Collecting HEPs

Continue until all HEPs are collected


That’s all there is to collecting HEPs!!

specialized gis skills at the swfwmd part 4: arcgis 202 – hydraulic element points

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