Road Naming Standards

This page details the road naming standards proposed by the Napa County GIS Standards Group. Essentially, we are proposing the use of the U.S. Postal Service Addressing Standards.

Here is a summary of the key standards:

Do not spell out numeric streets. For example, First Street should be 1st Street.

Omit all punctuation except for the hyphen in the zip+4 or when absolutely necessary.

Spell city names out in their entirety.

Abbreviate all directionals unless they are a part of the actual street name. Valid abbreviations are: N, S, E, W, NW, NE, SW, SE.

Highways should not be abbreviated. For example, ST HWY 29 should be STATE HIGHWAY 29.

Post office boxes should be designated with "PO BOX".

Street types should be abbreviated to the appropriate 2 - 4 character street type code.

The table below shows a suggested database structure for all tables that contain address information.

Field Name	Field Type	Field Length	Description
Street Number	Character	10	Street number
Pre-Directional	Character	2	Direction designator - north, south, etc.
Street Name	Character	50	Street Name
Street Type	Character	4	Street Type abbreviation
Post-Directional	Character	2	Direction designator - north, south, etc.
Additional Address	Character	50	Additional address info such as PO BOX.
City	Character	2	Postal service community.
State	Character	2	2 character state abbreviation
Zip	Character	10	Zip code including +4 component.

Please contact the Napa County GIS Staff if you have any questions about this project.