Populating the z-value with a custom value (Production Mapping)
The z-values for features can be updated using a specified value. If you know the value that should be used as the z-values for your features, you can indicate it on the Z Populate dialog box and populate the features using the Populate Z For Selected Feature(s) tool.
- Start ArcMap.
 - If necessary, load data in the map.
 - On the main menu, click Customize > Toolbars > Production Editing.
 - On the main menu, click Customize > Toolbars > Production Z Management.
 - 
Click the Production Start Editing button 
 on the Production Editing toolbar.
Note:The Manage Features and Create Attributes, Update Attributes, or Metadata Attributes windows automatically appear when you start an edit session using the Production Start Editing tool.
Tip:If the Create Attributes, Update Attributes, or Metadata Attributes window does not appear when you start an edit session, click the Show/Hide Attributes button
 on the Manage Features window. - 
Select the features whose z-values you want to populate using  the Edit  tool 
 on the Production Editing toolbar. 
 - 
Click the Populate Z For Selected Feature(s) button 
 on the Production Z Management toolbar. 
The Z Populate dialog box appears.

 - Choose the Populate Zs from value entered option.
 - Type a value in the Populate Zs from value entered text box.
 - 
Click OK. 
A message appears that indicates how many features were populated using the Populate Z for Selected Features tool.
 - Click OK.