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HERS-ST Highway Economic Requirements System - State Version: User's Guide

Chapter 6 Working with Input Data (Highway and State)

This chapter addresses the Highway and State Improvements data that HERS-ST uses during an analysis. The information in this chapter describes these data types and the preparation needed for use.

The Data HERS-ST Uses

Understanding the data used in the HERS-ST analysis is a critical part of using the software effectively. When HERS-ST processes an analysis, the highway and State Improvements data provide the following information:

Data Type (External) Provides
Highway Base-year descriptions for each highway section to be analyzed plus current and future traffic volumes for each section.
State Improvements Optional, user-specified improvements to highway sections that override the HERS-ST standard analysis.

In addition to the Highway and State Improvements data, HERS-ST also can use an optional Intermediate year file that provides more information about future traffic volumes than can be communicated in a conventional highway data record. In particular, an Intermediate year file can be used to:

  • Extend forecasts of traffic volume from a single "forecast" year to two future years, an "intermediate" year and a "final" year.
  • Forecast significant changes in traffic volumes that are expected to occur in the intermediate year as a result of expected changes in the highway network, such as the opening of a new road.

notes or hints to make using the application easier

You can learn more about funding periods in the Glossary and Key Concepts chapter.

Highway Data

In general, the starting point for the HERS-ST analysis is a data file containing information on a set of highway sections (e.g., all sections of the State highway system or some subset of these sections) for a base year. HERS-ST analyzes the specified set of highway sections over an analysis period consisting of one or more funding periods (FPs), starting in the base year specified. You specify the length and number of FPs, although the use of 3 to 6 FPs, each with a length of from three to seven years, is recommended. HERS-ST can analyze a maximum of 25 funding periods in a single run.

You may choose the source of the highway data you will use. The source data must be prepared in the same format as the Highway Performance Monitoring System (HPMS) Sample Data (Table 6-1), which States submit annually to FHWA. This data set contains descriptions of each highway section to be analyzed, one record per highway section. There are 98 fields for each record, and the data must be in comma-delimited format in order to be read into HERS-ST.

notes or hints to make using the application easier

The HPMS Field Manual provides more information and is available at: www.fhwa.dot.gov/ohim/hpmsmanl/hpms.cfm

All 98 fields (shown in columns) must be present, although HERS-ST does not use them all in the analysis. Table 6-1 shows the 98 HPMS sample section data items and the type of data required. The shaded rows indicate the data items not used by HERS-ST. These unused fields can be left blank, but the comma must remain. There must be 97 commas, translating to 98 fields (the last one does not need a comma). For the fields not used by HERS-ST, the commas can be adjacent (no space).

HERS-ST is not designed to handle rural minor collectors or sections on the two local functional systems. To allow States to analyze sections on these three systems, HERS-ST treats all sections on these systems as if they were rural major collectors or urban collectors, as appropriate. Accordingly, statistics printed by HERS-ST for rural major collectors actually include information for any rural minor collectors and rural local roads analyzed; and statistics for urban collectors similarly include information for any urban streets analyzed that are smaller than collectors.

An important consideration in running the HERS-ST model is whether the data include the complete set of sections that are of interest for the analysis, or whether they represent only a subset of the sections. An example of the former would be an analysis of a particular corridor, in which data for each section in the corridor are available (this would be called "universal" data). An example of the latter would be an analysis involving a sample of all the highway sections in an area, with inference to be made from this sample about highway conditions and performance on the entire system (this would be called "sample" data). If the data are universal data, then it is important that expansion factors for each section (Field 49 in Table 6-1) all be set equal to 1. If sample data are being used, then the expansion factors should be set to values greater than one. See the HPMS Field Manual for more information on sample selection and expansion factors.

Table 6-1. HPMS Sample Selection Data Items (yellow indicates not used by HERS-ST)
Item No. Data Item Data Type Used by HERS-ST
1 Year of Data Numeric; Integer Yes
2 State Code Numeric; Codes Yes
3 Reporting Units - Metric or English Numeric; Codes Yes
4 County Code Numeric; Codes Yes
5 Section Identification Character Field Yes
6 Is Standard Sample Numeric; Codes Yes
7 Is Donut Sample Numeric; Codes No
8 State Control Field Character Field Yes
9 Is Section Grouped Numeric; Codes No
10 LRS Identification Character Field Yes
11 LRS Beginning Point Numeric; Decimal Yes
12 LRS Ending Point Numeric; Decimal Yes
13 Rural/Urban Designation Numeric; Codes Yes
14 Urbanized Area Sampling Technique Numeric; Integer No
15 Urbanized Area Code Numeric; Codes No
16 NAAQS Nonattainment Area Code Numeric; Codes No
17 Functional System Code Numeric; Codes Yes
18 Generated Functional System Code S/W Calculated Yes
19 National Highway System (NHS) Numeric; Codes No
20 Planned Unbuilt Facility Numeric; Codes Yes
21 Official Interstate Route Number Character Field No
22 Route Signing Numeric; Codes No
23 Route Signing Qualifier Numeric; Codes No
24 Signed Route Number Character Field No
25 Governmental Ownership Numeric; Codes No
26 Special Systems Numeric; Codes No
27 Type of Facility Numeric; Codes Yes
28 Designated Truck Route Numeric; Codes No
29 Toll Numeric; Codes No
30 Section Length Numeric; Decimal Yes
31 Donut Area Sample AADT Volume Group Identifier Numeric; Integer No
32 Standard Sample AADT Volume Group Identifier Numeric; Integer No
33 AADT Numeric; Integer Yes
34 Number of Through Lanes Numeric; Integer Yes
35 International Roughness Index (IRI) Numeric; Decimal Yes
36 Present Serviceability Rating (PSR) Numeric; Decimal Yes
37 High Occupancy Vehicle (HOV) Operations Numeric; Codes Yes
38 Electronic Surveillance Numeric; Codes No
39 Metered Ramps Numeric; Codes No
40 Variable Message Signs Numeric; Codes No
41 Highway Advisory Radio Numeric; Codes No
42 Surveillance Cameras Numeric; Codes No
43 Incident Detection Numeric; Codes No
44 Free Cell Phone Numeric; Codes No
45 On-Call Service Patrol Numeric; Codes No
46 In-Vehicle Signing Numeric; Codes No
47 Sample Identifier Character Field Yes
48 Donut Area Sample Expansion Factor Software Calculated No
49 Standard Sample Expansion Factor   Yes
50 Surface/Pavement Type Numeric; Codes Yes
51 SN or D Numeric; Decimal Yes
52 General Climate Zone Software Set Yes
53 Year of Surface Improvement Numeric; Integer Yes
54 Lane Width Numeric; Decimal Yes
55 Access Control Numeric; Codes Yes
56 Median Type Numeric; Codes Yes
57 Median Width Numeric; Decimal Yes
58 Shoulder Type Numeric; Codes Yes
59 Shoulder Width - Right Numeric; Decimal Yes
60 Shoulder Width - Left Numeric; Decimal Yes
61 Peak Parking Numeric; Codes Yes
62 Widening Feasibility Numeric; Codes Yes
63 Length Class A Curves Numeric; Decimal Yes
64 Length Class B Curves Numeric; Decimal Yes
65 Length Class C Curves Numeric; Decimal Yes
66 Length Class D Curves Numeric; Decimal Yes
67 Length Class E Curves Numeric; Decimal Yes
68 Length Class F Curves Numeric; Decimal Yes
69 Horizontal Alignment Adequacy Software Calculated Yes
70 Type of Terrain Numeric; Codes Yes
71 Vertical Alignment Adequacy Software Calculated Yes
72 Length Class A Grades Numeric; Decimal Yes
73 Length Class B Grades Numeric; Decimal Yes
74 Length Class C Grades Numeric; Decimal Yes
75 Length Class D Grades Numeric; Decimal Yes
76 Length Class E Grades Numeric; Decimal Yes
77 Length Class F Grades Numeric; Decimal Yes
78 Percent Passing Sight Distance Numeric; Integer Yes
79 Weighted Design Speed Software Calculated Yes
80 Speed Limit Numeric; Integer Yes
81 Percent Single Unit Trucks - Peak Numeric; Integer Yes
82 Percent Single Unit Trucks - Average Daily Numeric; Integer Yes
83 Percent Combination Trucks - Peak Numeric; Integer Yes
84 Percent Combination Trucks - Average Daily Numeric; Integer Yes
85 K-Factor Numeric; Integer Yes
86 Directional Factor Numeric; Integer Yes
87 Number of Peak Lanes Numeric; Integer Yes
88 Left Turning Lanes Numeric; Codes Yes
89 Right Turning Lanes Numeric; Codes Yes
90 Prevailing Type of Signalization Numeric; Codes Yes
91 Typical Peak Percent Green Time Numeric; Integer Yes
92 Number At-Grade Intersections - Signals Numeric; Integer Yes
93 Number At-Grade Intersections - Stop Sign Numeric; Integer Yes
94 Number At-Grade Intersections - Other/No Control Numeric; Integer Yes
95 Peak Capacity Software Calculated Yes
96 Volume/Service Flow Ratio (V/SF) Software Calculated Yes
97 Future AADT Numeric; Integer Yes
98 Year of Future AADT Numeric; Integer Yes
HERS-ST Highway Data Fields

In addition to the 98 HPMS fields defined in Table 6-1, the highway data used by HERS-ST has several other fields, as described in Table 6-2.

Table 6-2. HERS-ST Highway Data Fields.
Item Number Field Description Data Type
NA Comment General Purpose Comment 100 Characters
99 LCF Local Cost Factor Numeric; Decimal
100 UDF1 User Defined Field 1 50 Characters
101 UDF2 User Defined Field 2 50 Characters
102 UDF3 User Defined Field 3 50 Characters
103 UDF4 User Defined Field 4 50 Characters
Using the Highway Data Window

A Workset can have several sets of highway data, although only one can be active at a time. The active highway data is indicated by an option button displayed to the left of the data set name in the Workset tree (Figure 6-1)

Figure 6-1. Highway Data in the Workset Tree.

Figure 6-1. Highway Data in the Workset Tree.

The highway data window is the primary interface you use to enter and edit the highway section information that HERS-ST processes. You display the highway data window by double-clicking a highway data branch in the Workset tree or by selecting the Display item in its popup menu. This window also allows you to view a graphical image of the highway data sections you are including in an analysis. The interface is displayed in two panes (Figure 6-2). The left pane shows a hierarchal tree displaying the structure of the highway data window and the right pane shows the specific details for the selected portion of the structure.

Selecting the root of the tree displays general information about the highway data, including the name, description, GIS shape file, last user to modify the data, and when the data were modified.

Figure 6-2. Highway Data Window (Root Level).

Figure 6-2. Highway Data Window (Root Level).

Selecting a GIS Shape File

To use the HERS-ST map feature, you must specify a GIS Shape file. A Shape file is a spatial data format, developed by Environmental Systems Research Institute, Inc. (ESRI). A shape file stores non-topological geometry and attribute information for the spatial features in a data set. These spatial features can be a line (highway), point (city), or area (county boundaries).

To select a Shape file, click the Load button and the Shape file browser window (Figure 6-3) will appear. Browse to the location of your Shape file and select it. Once selected, you must specify the data fields that will be used to link the HERS-ST data with the Shape file database. There are three fields for linking:

  • FIPS State Code - Optional. This item identifies the field that contains the State FIPS code for the highway section. If all the highway sections are in the same State, this field can be left blank.
  • FIPS County Code - Required. This item identifies the field that contains the County FIPS code for the highway section.
  • Section ID - Required. This item identifies the field that contains the county-wide unique identifier for the highway section.

Figure 6-3. Shape File Browser.

Figure 6-3. Shape File Browser.

The items under the Shape File column will display drop-down lists containing all of the data fields in the Shape file database. Click the down-arrow buttons and select the fields from the lists that contain the State and County FIPS code and section ID. If your Shape file database does not contain the County FIPS code and section ID, it cannot be linked to the HERS-ST data. The Shape file needs to have the same break points as the Highway Data file. That is, each link of the Shape file must represent a corresponding HPMS section.

Working with Highway Data

Selecting the Sections branch of the tree (Figure 6-2) displays a table containing information about each section of highway data (Figure 6-4). The table provides layout formatting and editing capabilities through popup menus. You activate these menus by RIGHT-clicking on individual records or on the column headers. Highway sections that contain validation errors are highlighted with a red-tinted background.

Figure 6-4. Highway Data Window (Sections Level).

Figure 6-4. Highway Data Window (Sections Level).

The left-most column of the table provides a check box for each record that indicates if the highway section is active or inactive. An active record is used by HERS-ST for the analysis. An inactive record is stored, validated, and maintained in the database, but is not used for the analysis.

Record Menu. After RIGHT-clicking on an individual record, a popup menu appears providing the capability to add, remove, validate, activate and deactivate, edit, cut, copy, or paste the selected record. A secondary edit window is available for editing a single highway data section in a more readable vertical format. You activate the Section Editor window (Figure 6-5) by double-clicking a record in the table or by selecting the Edit item in the popup menu. This window floats above all other windows and tracks with the active row selected in the sections table.

The popup menu also provides a sub-menu with options that affect the table as a whole (Figure 6-6). To access this sub-menu, select the Table item in the popup menu. The Table menu allows you to select the active records (Checked) that are used for the HERS-ST analysis, validate the highway data records, and save and restore the layout of the highway data table.

Symbol: Letter Eye for Information

The rows displayed in the Section Editor window match the format of the columns displayed in the Highway Data table. Columns that are hidden in the layout of the Highway Data table will not appear in this window.

Figure 6-5. Section Editor Window.

Figure 6-5. Section Editor Window.

Figure 6-6. Highway Data Table (Table Menu).

Figure 6-6. Highway Data Table (Table Menu).

  • Display only the active or inactive records
  • Display all records
  • Build a SQL query to select which records are active based on one or more of their field values.
  • Validate all records in accordance to the HPMS validation rules.
  • Select all records in the table.
  • Save or Restore the current table layout.

Column Menus. By RIGHT-clicking a column header, you activate other popup menus that allow you to manipulate columns of data (Figure 6-7). Items in these menus apply only to the column that was clicked.

Figure 6-7. Highway Data Table (Column Menus).

Figure 6-7. Highway Data Table (Column Menus).

  • Sort the column in either ascending or descending order.
  • Hide and show columns.
  • Enable and disable HPMS validation rules for individual columns.
  • Search and replace values in the column.
  • Select the active records.
  • Hide and show the active records.
Configuring the Table Layout

You can configure the presentation layout of the highway sections table. For example, you might rearrange the column order, hide unwanted columns, and adjust column widths. You can save your layouts with specific names to a library for future use by selecting the Table/Save Layout item in the popup menu. To restore a previous layout, select it by its name from the Restore Layout item in the popup menu.

To reorder the columns of the sections table, drag the column to the desired position and drop it. To resize a column, drag the column divider in the header to the desired width. Use the popup menus to hide and show columns.

As indicated previously, HERS-ST does not require all of the fields of the highway data. The unused highway data fields can be hidden automatically by activating the HERS-ST Layout option on the popup menu. Although the unused fields are hidden, their data are still preserved, saved, and exported as usual. To return to full view of the highway data, deactivate the HERS-ST layout mode by un-checking it in the menu.

Sorting Records

You can sort the records in the sections table by column by clicking on the header of the column. Repeat clicking of a column header toggles the sort between ascending and descending order. You also can sort by using the popup menus. To sort multiple columns, select a column group by clicking on the column headers while pressing the SHIFT key. Then, select an ascending or descending sort from the menu.

Importing from an HPMS File

Highway data that is stored in an external HPMS formatted file can be imported directly to a highway data item. The imported highway data can either replace or be appended to any existing data. To start the import process, select the Import item from the highway popup menu and browse to the file you want to import.

Not all of the records in the HPMS file may represent a complete HPMS sample section. A standard HPMS sample section is determined by the Is Standard Sample field (Table 6-1) of the HPMS Record. You may choose to ignore these incomplete records when importing the highway data in the environmental option settings.

When a record in the HPMS file is incomplete, default values will be assigned to any missing fields when it is imported. You may specify what the default value should be for each HPMS field by entering highway data default values into the environmental options as discussed in Chapter 11.

Symbol: Letter Eye for Information

Importing from an external database requires that your highway data already exist in an electronic form such as a Microsoft Access database or other ODBC readable data.

Importing from an External Database

You can import highway data directly from an external database using a one-to-one field map to control how the data are loaded. To start the import process, select the External Database / Import item from the highway popup menu, select your data source, and define the field map.

The field map allows you to specify which data table in the data source you want to import data from and to map its data fields to the HERS-ST highway data fields (Figure 6-8). Select the data table that contains external highway data, then specify which fields corresponds to the HERS-ST highway data fields. For any field that is not provided in the external data, you can select the (Default) option or use a literal value that you either select from the drop-down list or type in yourself.

Figure 6-8. Data Field Map.

Figure 6-8. Data Field Map.

Symbol: Letter Eye for Information

Validation rules are progressive. That is, the failure of one rule may, in turn, cause the failure of other rules. When working with a highway section with multiple validation errors, search first for a common cause before addressing each issue separately.

Validating Records

Validation of records occurs during the import of a highway data file and can also be invoked from the highway data table. When importing a highway data file, HERS-ST automatically validates records or asks you whether validation checking should be performed. The option to automatically validate records during import is determined by the application environment options discussed in Chapter 11. From the highway data table, you can validate individual records or the complete highway data set using the Validate items in popup menus. Records that fail the validation test are displayed with a red tinted background.

When validating the highway data, error messages for each record are displayed in a list in the bottom pane of the window (Figure 6-4). These rules can be filtered for a specific highway section, HPMS field, or error code. DOUBLE-click the error message to see the highway section and data field that caused the error. The error messages can be organized four ways:

  • All Error Messages. This option will display all the error messages that exist for the entire set of highway sections.
  • By Section. This option will display only the error messages that are applicable to the currently selected highway section.
  • By Field. This option will display the error messages for all highway section that apply to the currently selected field.
  • By Error Code. This option will display all the unique error messages that exist for the entire set of highway sections. With this option, when you DOUBLE-click an error message, all the highway sections that have this error will be displayed.

Symbol: Letter Eye for Information

You can disable individual highway validation rules in the application option settings or from the column header popup. You also can disable validation rules for sections that are not a standard sample.

When editing a data field of a section, the new value is verified against the appropriate validation rules. If an error is detected, you can choose to ignore the violation on that occasion or restore to the field's previous value.

The Highway Data validation rules are organized by HPMS field. That is, each field may have one or more rules associated with it. You can enable or disable all the validation rules for a particular field from its columns popup menu. Individual rules can also be enabled and disabled in the environmental option settings.

Selecting Records

Records that are selected for use (active) are designated with a check mark in the fixed column at the left of the grid. Only records that are active are used when executing the HERS-ST analysis, exporting the highway data to a file, or creating a clone. You can choose to view only the active records by selecting the Show Checked option from the tables' popup menu. To return to viewing all records, select the Show All option.

You can activate a record by highlighting it and clicking its check box. You can activate the entire set of records in the grid using the columns popup menu.

Individual rows and groups of rows may be highlighted collectively from the table by clicking them with the mouse while holding down the CTRL or SHIFT key respectively. Selecting the Select All option of the tables' popup menu highlights the entire table at once. Once a group of rows is highlighted, you can mark them as active or inactive by selecting the Check or Uncheck options in the popup menu.

Using the Query Builder also offers several features for selecting the active records (Figure 6-9). This window appears when you select the Check by Query option on the popup menu. This window allows you to build complex criteria conditions for selecting records. You can type the desired selection criteria directly into the query text box or build it using the Fields, Values, Functions, and Operators listed. DOUBLE-click an item in any of these lists to copy that item to the query text box.

Figure 6-9. Query Builder Window.

Figure 6-9. Query Builder Window.

Symbol: Letter Eye for Information

The syntax of the query text represents the WHERE clause of a Structured Query Language (SQL) statement. (See Glossary and Key Concepts.)

The list of fields contains all of the highway data field names. The list of values contains all the unique values of the selected field. The list of operators and functions contains a list of commonly used logical and comparison operators and built-in functions that can be used.

The Verify button will validate the syntax of the query to ensure that it is correct before you apply it. If syntax errors are found, a message will be displayed directing you to its probable cause.

Once the query text is complete, you choose one of three actions:

  • Replace. This option clears the active highway sections and activates only those records that meet the criteria specified in the query.
  • Append. This option does not affect any existing selection of active records, but adds any additional records that meet the criteria specified in the query.
  • Remove. This option deactivates those records that meet the criteria specified in the query while leaving any other selected records active.

You can save the query text with a specific name to a library for future use by clicking the Save button. To reload a previously saved query, select it by its name from the Load item under the Queries menu.

Adding and Deleting Records

To add a record to the highway section list, select the Add Record option from the popup menu. The new record, which is a copy of the current record, is added to the end of the list and can be modified as appropriate. To delete a record or set of records, highlight the rows that are to be deleted and then select the Remove Record option from the popup menu.

Symbol: Exclamation Point

Be careful when deleting records. You cannot recover a deleted section record.

Viewing the GIS Map

Selecting the Map branch of the tree (Figure 6-2) displays a GIS map that graphically depicts the highway sections (Figure 6-10). Three highway selections based on the highway attribute data are automatically created for you when the map is first displayed.

  • Errors. These sections are highlighted in red and represent the highway sections that have failed one or more of the HPMS validation rules.
  • Selected Sections. These sections are highlighted in blue and represent the active highway sections that have been selected for analysis as designated with a check mark in the fixed column at the left of the sections table.
  • Sample Sections. These sections are highlighted in green and represent the highway sections that are flagged as standard HPMS sample sections as designated with a check mark in the Sample column of the sections table.

Symbol: Letter Eye for Information

The map feature is only available when a GIS shape file is provided and linked to the highway data as described in Figure 6-3.

Figure 6-10. Highway Data Window (Map Level).

Figure 6-10. Highway Data Window (Map Level).

Symbol: Exclamation Point

The use of this GIS map is intended to provide a graphical interface to assist you in working with highway sections. As such, its configuration is not preserved when the map is closed. To create GIS maps that you can save, use the GIS map report described in Chapter 10.

Selecting Highway Sections using the GIS Map

You can create a set of active highway sections to be analyzed by HERS-ST using the GIS map by creating a Map Selection on the Highway Data map layer and then adding highway sections to it. There are three methods of adding highway sections.

  • Select by Attributes. Select highway sections using SQL query criteria.
  • Select by GIS. Select highway sections manually using the mouse.
  • Select by Shortest Path. Select a highway corridor between two points.

Symbol: Letter Eye for Information

See Chapter 10 for more detailed information about using the GIS map and creating map selections.

Once you have selected the highway sections, click the Highway button on the tool bar to select the corresponding sections in the sections table. You will be asked if you wish to append or replace any previously selected sections.

GIS Map Backgrounds

This map will automatically display a background image of the State's counties, water, and urban areas based on the FIPS code used in the highway data. The background image is created using the States map information located under the root Maps directory specified in the application environment options. If this directory does not exist or the map information cannot be found, then the maps background will not appear.

State Improvements Data

A Workset can have several sets of State Improvements data, although only one can be active at a time. The active State Improvements data is indicated by an option button displayed to the left of the name of the dataset in the Workset tree. You display the State Improvements data window by double-clicking an Improvements branch in the Workset tree (see Figure 6-11) or by selecting the Display item in its popup menu.

Figure 6-11. State Improvements Workset Tree.

Figure 6-11. State Improvements Workset Tree.

HERS-ST uses the State Improvements data when operating in the Override Mode. This mode provides you with the ability to override improvement recommendations produced by HERS-ST with user-specified improvements provided in the Improvements dataset. This user-defined information supplements the highway data and overrides the HERS-ST improvements on any given highway section.

Like the highway data window, this interface is displayed in two panes. The left pane shows a hierarchal tree displaying the structure of the State Improvements data, and the right pane shows the specific details for the selected portion of the structure.

Select the root of the tree (Figure 6-12) to display general information about the State Improvements data including its name, description, the last user to modify the data, and a timestamp of when the modification occurred.

Figure 6-12. State Improvements Data Window (Root Level).

Figure 6-12. State Improvements Data Window (Root Level).

Selecting the Improvements branch of the tree displays a table containing the information about each section that has a State-specified improvement defined (Figure 6-13). You can specify up to ten improvements for each section. The number of improvements specified for a given section is display in the first column and is followed by the State code, County code, and Highway Section Identification number. Improvements are described in chronological order starting with the first improvement, then the second improvement and so on.

Figure 6-13. State Improvements Data Window (Improvements Level).

Figure 6-13. State Improvements Data Window (Improvements Level).

Next, each of the ten possible improvements for the section is described in a set of six columns each (Table 6-3 items 5 thru 10). When the main improvements branch is selected, all 60 columns are displayed. If you select one of the specific improvement branches from the tree, you will see only the six columns for that improvement. If you select a specific improvement branch that is greater than the number of improvements for a section, then its six columns will be blank and will not be editable. To hide these sections, select the Table/Show Improvements item from the tables' popup menu.

Table 6-3. Format of State Improvements.
Item Number Data Item1 Name Data Type
1 The nn included after the "SF" in fields 5 through 10 represents the improvement index (1-10).
1 Improvements Number of Improvements Numeric; Integer
2 State State FIPS Code Numeric; Codes
3 Cnty County FIPS Code Numeric; Codes
4 SecID Section Identifier Character Field
5 SFnn_Year Year of First Improvement Numeric; Integer
6 SFnn_IType Type of Improvement Numeric; Codes
7 SFnn_Ovrd Override Flag Numeric; Codes
8 SFnn_ImpC Cost of Improvement Numeric; Decimal
9 SFnn_Ladd Lanes Added Numeric; Integer
10 SFnn_CapInc Increase in Capacity Numeric; Integer

Menus. By RIGHT-clicking on the table body or column headers, you activate popup menus that allow you to manipulate columns of data (Figure 6-14).

A secondary edit window is available for editing the improvements for a single highway section in a vertical format (Figure 6-15). You activate the Improvements Editor window by double-clicking a record in the table or by selecting the Edit item in the popup menu. This window floats above all other windows and tracks with the active row selected in the improvements table.

Figure 6-14. State Improvements Table Menus.

Figure 6-14. State Improvements Table Menus.

  • Sort the column in either ascending or descending order.
  • Search and replace values in the column.
  • Add, Edit and Remove records.
  • Create a record set from an existing Highway Data set or Section Conditions.
  • Hide and show the active records.

Figure 6-15. State Improvements Data Editor.

Figure 6-15. State Improvements Data Editor.

Synchronizing Records

Each record in the State improvements data corresponds to a record in the highway data. You can synchronize these two data sets so that when both the highway data and improvements data windows are displayed, the selected record of the State data tracks with its counterpart in the highway data and vice versa. Synchronizing is enabled under the View menu on the main application window.

Creating Records from Highway Data

You can easily create a set of State improvement records from an existing set of highway data records. This feature will create a record for each active highway section in the highway data. The State and county FIPS codes and the section identification field are copied to the new record. If a record with these fields already exists, it will NOT be duplicated. To create a set of State improvement records, select the source highway data by its name in the Create From item in the popup menu.

Symbol: Letter Eye for Information

You must open and display the highway data window or the section conditions window in the applications workspace before either can be used to create improvement records.

Creating Records from Section Conditions Data

When creating records from Section Conditions data, all existing records in the State improvements data will be deleted and a new record will be created for each highway section that has been recommended for improvement. If the section has more than one recommendation, then the next improvement will be listed as the section's second improvement and so on.

Sorting Records

You can sort the records in the sections table by column by clicking on the header of the column. Repeat clicking of a column header toggles the sort between ascending and descending order. You also can sort by using the popup menus. To sort multiple columns, select a column group by clicking on the column headers while pressing the SHIFT key. Then, select an ascending or descending sort from the menu.

Specifying Improvements

Each State improvement record describes one or more improvements for a single highway section in chronological order. For the first improvement, you specify a particular type of improvement for a given year. HERS-ST can only implement one user-specified improvement per funding period. For HERS-type improvements, you specify the improvement type using the improvement codes shown below (Table 6-4). The improvement code is a bit-weighted number where any combination of improvement type and alignment produces a unique code.

Symbol: Exclamation Point

HERS-ST requires the non-HERS type improvements be assigned codes that are divisible by 20.

Table 6-4. Improvement Codes.
Abbr Improvement Improvement Code
Without Alignment Improvement With Alignment Improvement
RS Resurface 1 11
RSSH Resurface and improve shoulders 2 12
RSWL Resurface and widen lanes (minor widening) 3 13
RSNC Resurface and add normal-cost lanes (major widening) 4 14
RSHC Resurface and add high-cost lanes 5 15
RC Pavement reconstruction 6 16
RCWL Pavement reconstruction with wider lanes 7 17
RCNC Pavement reconstruction and add normal-cost lanes 8 18
RCHC Pavement reconstruction and add high-cost lanes 9 19

You can define your own improvement code to specify special improvement types, such as intersection modification or grade separation. User-defined improvement types must be assigned codes that are divisible by 20 when they are not combined with pavement, widening, or alignment improvements. These codes can be combined with HERS-ST improvement codes for pavement, widening, and alignment improvements. You can use the dialog box to edit the improvement-type columns (Figure 6-16).

Figure 6-16. Improvement-Type Dialog.

Figure 6-16. Improvement-Type Dialog.

Improvement Cost. For non-HERS-type improvements, you will need to specify the total improvement cost. Improvements that are not HERS-type or are combinations of HERS-type and non-HERS-type are referred to as special improvements.

Lanes Added. For improvements that involve adding lanes, you specify the number of lanes to be added. An entry in this field is required for improvement types that add normal cost or high cost lanes. If lanes are to be added but the this field is zero, HERS-ST adds either one lane on one-way facilities or two lanes on two-way facilities.

Capacity Increase. This field may, and in some rare cases must, be used to provide HERS-ST with your estimate of peak-period, peak-direction capacity. On two-way roads, other than rural three-lane roads, HERS-ST assumes that lanes are added in pairs, with equal numbers of lanes added in each direction. For these roads, the current system does not have procedures for estimating capacity if the number of lanes being added in each direction are not equal. If they are not equal, you must specify the resulting increase in peak-period peak direction capacity; otherwise the number of added lanes is adjusted appropriately. For rural two- and three-lane roads, capacity changes should be specified as changes in two-way capacity.

Symbol: Letter Eye for Information

If an improvement code includes both HERS and non-HERS type improvements, the override flag should be set to YES.

Override Flag. The override flag is used to indicate whether HERS-ST has any leeway in modifying a user-specified improvement. If the override flag is set to Yes, the improvement is selected just as described. If it is set to No, these fields describe the minimum improvement that will be selected. In this case, HERS-ST may identify a "more aggressive" improvement.

The override flag can also be used to identify funding periods during which no improvements should be implemented on a given section. For a given funding period, this is accomplished by specifying: a Year of Improvement that falls within that funding period; an improvement type of 0; and an Override Flag of Yes.

Intermediate Year Data

The intermediate year data are used to provide extra information about one or more highway sections that are described in the highway data. In general, the intermediate year file will contain information for new highway sections that are not expected to open until an intermediate year during the analysis period, as well as data for many existing sections whose traffic levels may be expected to increase or decrease when the new roads opens. Such changes may include reductions in traffic resulting from the opening of a new parallel road or as increases that may occur on roads that feed a newly opened road.

Symbol: Letter Eye for Information

The Intermediate year data are read from an external file that is manually created and referenced from the Run Wizard. See Chapter 8.

The information contained for each section is shown in Table 6-5. Sections not represented in the intermediate year data are analyzed entirely on the basis of information contained in the highway data.

Symbol: Exclamation Point

The intermediate year data only uses the linear growth method for forecasting AADT. HERS-ST will automatically switch to the linear growth method even if geometric growth is selected in the Control settings.

Table 6-5. Intermediate Year Data.
Item Field Name Description
1 State State FIPS Code
2 County County FIPS Code
3 Section_ID Section Identifier
4 IntYear Interim Forecast Year
5 I_VOL_I Forecast traffic volume for the interim year before any major network changes.
6 I_VOL_F Forecast traffic volume for the interim year after any major network changes.
7   Not Used
8   Not Used
9 FYEAR Final forecast year
10 FAADT Forecast traffic volume in final forecast year
11 TDM_ID Travel demand model identifier. This is an optional field that is not used by HERS-ST.

Fields 5 and 6 contain forecasts of the AADT that will exist on the section immediately before and after the change in the highway network. For a No Build scenario, these forecasts should be identical. For a Build Scenario they can be quite different.

Field 10 is used to provide a forecast of the AADT volume in the final year specified in field 9. If these fields are not zero, this forecast is used instead of the forecast for the future AADT specified in the highway data; otherwise the values in the highway data are used.

Symbol: Letter Eye for Information

HERS-ST assumes that all changes specified in the intermediate data occur in the middle of the funding period that contains interim year.

New Highway Sections

New sections are assumed to carry no traffic until the middle of the funding period in which they open. The initial AADT on each of these sections is specified in Field 6. Since the section carries no traffic until it is opened, Field 5 should be set to zero. Also, in the highway data, new sections should be described as carrying no traffic by setting the highway data field 33 (AADT) to zero.

Traffic growth on new sections is estimated using the standard HERS-ST forecasting procedures in conjunction with a section-specific growth rate and user-specified, system-wide elasticity parameters. For each new section, the growth rate to be used is determined by linear interpolation between the year of its initial AADT (fields 4 and 6) and the year of its final AADT (fields 9 and 10).

Prior to opening, new sections carry no traffic and they are ignored when computing system-wide road-miles and lane-miles. After opening, these sections carry traffic and they are included in calculating road-miles and lane-miles.

TRY IT ON YOUR OWN!

Initiate a New Workset
  1. Click the New Workset button in the tool bar.
  2. Enter a name for the workset.
  3. Select the source for the Highway Data. If you are importing source data from a highway file, browse to the file.
  4. Click NEXT.
  5. Select the source for the State Improvements Data (if any). If you are importing source data from a state improvements file, you can browse to the file.
  6. Click NEXT.
  7. Select the source for the HERS-ST Control Settings. If you are importing control settings from a control file set, you can browse to the files.
  8. Click NEXT.
  9. Select the source for the HERS-ST Parameter Settings. If you are importing parameter settings from a parameter file set, you can browse to the files.
  10. Click NEXT.
  11. Select the source for the HERS-ST Output Settings.
  12. Click OK. The new Workset tree displays in the left windowpane with branches for Highways and Improvements data, Control, Parameter and Output settings.
Edit Highway Data

1. Double-click the Highway Data branch in the Workset tree or select the Display item from its popup menu. The Highway Data window displays.

3. Enter a name for the highway data.

4. Click the Load button and specify the GIS shape file and link fields.

5. Click the Sections branch. A table displays that contains information about each section of highway data.

6. Right-click the table area or column headers to access the popup menus and edit or reformat grid information.

7. Double-click in the table to display the Section editor window. Notice that the Section Editor window tracks as you select rows in the sections table.

8. Click the Map branch. A GIS map loads and display selections of the highway data that are active, contain validation errors, and are standard samples.

Edit Improvements Data

1. Double-click New Improvements branch in the workset tree or select the Display item from its popup menu. The Improvements Data window displays.

3. Enter a name for the improvements data.

4. Click on the Improvements branch. A table displays in the right windowpane containing information on each section that has a State-specified improvement.

5. Click the Improvements branch to display ten improvements branches.

6. Click the Second Improvements branch in the tree to view information on the second improvement for each section.

7. Double-click a record in the table to display the Improvements Editor window. Notice that the editor window tracks as you select rows in the table.

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Updated: 02/14/2013