County Maintained Road System

In 1968 the current road numbering system was established. Documents establishing and explaining the current road numbering system can be found here.  Information concerning the prior road numbering system is not available. 

A subset is the bridge numbering system.  The bridge numbering system is established by Caltrans and is utilized to identify the bridges on roads within the County Maintained Road System.  The format of the bridge numbering system is AABCCCC where:

AA is a two digit numerical code that represents the County that the bridge is in.  This is 04 for Humboldt County.

B is a single character that represents the owner of the structure. This is C for bridges in the Humboldt County Maintained Road System and signifies that the bridge is owned by a County or City. 

CCCC is a four digit numerical serial number that identifies the specific bridge.

Scans were made of the various paper road logs that have been found in the Department of Public Works files. It does not appear that road logs were published for every year. The scans were made from the best available copy. Some scans may be difficult to read because the original document is difficult to read. The road logs are listed in chronological order from oldest to newest. This is assumed to be the entire collection of road logs that the Department currently maintains. Some of the paper road logs may contain handwritten notations; the origins of which are not known. Newer road logs were published directly to .pdf format.

While a road may be listed in the road log, it is important to look at the mileage in the maintained mileage column to see how much of the road is maintained by the County. Many roads that are listed in old road logs have a zero entered in the maintained mileage column. These roads are not part of the county maintained road system and are not maintained by the County. Many of these roads have a 4 digit road number that does not follow the 1968 road numbering system. 

Roads are typically logged from south to north or from west to east. This means that the TO column in the road log is usually the southern or westerly terminus of the road; and the FROM column is the northerly or easterly terminus of the road. There are exceptions to this.

The use of the word END in the TO and FROM columns may mean a) that the road physically ends; or b) that road maintenance ends and that the road continues on as a public right of way; or c) that road maintenance ends and that the road continues on as a private right of way.

Road Logs are typically published in two formats:  Alphabetically ("ALPHA" or "A"), by street name in ascending order. Numerically ("NUMERIC" or "N"), by road number is ascending order. From 1951 to 1964, the road logs were published on State of California forms. It is not known if the State of California prepared these road logs -or- if the County prepared the road logs using State of California forms. Starting in 1965, the State of California published a computerized road log based upon edits provided to the State from the County. Starting with the 1998 road log, the County assumed publication of the road log from the State and the County began publishing the road logs. From 1998 to 2016 it appears that staff where maintaining two MS Excel files for the road logs: one sorted in ALPHA and the other sorted in NUMERIC. Discrepancies have been discovered between the ALPHA and NUMERIC road logs published for the same year. Starting in 2019, both the ALPHA and NUMERIC road logs have been published from same MS Excel file.  

Also starting in 2019, the road log was cleaned up and reformatted. The following revisions have since been done:

• Unabbreviated road names. When the road log was first computerized, due to limitations with computer storage, road names were abbreviated.
• Corrected road name typos; added missing road numbers to the TO and FROM columns. The road names and road numbers in the TO and FROM columns were audited to the Road Name and Road Number columns to ensure consistency of all data. 
• Updated the TO and FROM columns for clarify. END is used to note when road maintenance ends but the road continues on as non-county maintained. CUL DE SAC is used to note that the road physically terminates. Added CITY LIMIT to denote when the road continues on as a City road; same for National Park boundary, County Boundary, Tribal boundary, and State Park boundary.
• Obsolete columns were hidden (group sequence, road segment, non-add, 1/2&1/2, status, other area, urban area code, district, county, county number, mileage from tabs, un constructed, old system, non county, and AADT).
• Removed all entries that did not have any maintained mileage shown.  These primarily included unnamed roads with a four digit road number (Example:  2194). 
• Added the 2000 FHWA Functional Classifications from data download on 07/19/2000 from the Caltrans website. 
• Translated 2000 FHWA Functional Classifications format to 2008 FHWA Functional Classification format.
• Repurposed the segment column to correctly organize road segments with the same road number by postmile direction.
• Added Road Maintenance Area column.
• Added a statistical summary sheet showing the 1) break down of roads by functional classification in each road maintenance area; 2) the road mileage within 1993 urban boundary zone in each road maintenance area; 3) difference between the mileage in the MS Excel file compared to the reported mileage. 

Scans have been made of the various California Road System Maps that have been found in the Department of Public Works files. Maps are known to have errors. The Department does not maintain a list of known errors. The maps have not been added to this webpage as of this date. Contact 707.445.7205 for the road maps.

The County maintained road mileage is affected by actions of the Board of Supervisors to add or remove roads from the road system.  Scans were made of the various documents found in the Department of Public Works files. The scans have been made from the best available copy. Some scans may be difficult to read because the original document is difficult to read. The agenda items have not been added to this webpage as of this date. Contact 707.445.7205 for agenda items. 

The County GIS contains a road layer. For those wanting to download the roads layer, the shape file can be downloaded here: https://humboldtgov.org/276/GIS-Data-Download.  The road layer was not prepared by Public Works and has not been audited by Public Works for accuracy. The following is a discussion of the types of known issues with the roads layer in the County GIS:

1. There are instances were a county maintained road continues on as a non-county maintained road. The GIS is not accurate in creating a break in the road and designating which portions of the road are county maintained -vs- not county maintained. Example:  Shadowbrook Street (3H241) is county maintained for 0.07 mile; the GIS has the entire length of Shadowbrook Street coded with 3H241 for the State Road Number field.
2. There are instances where there are roads located in different geographic areas of the county that have the same road name but are assigned the same road number in the State Road Number field.  Example:  Central Avenue in Fields Landing has the State Road Number field coded with the road number for Central Avenue in McKinleyville (A4L800) instead of 3J730.
3. Non-County maintained roads having the State Road Number field coded with a County road number.
4. County maintained roads not having the State Road Number field coded with a County road number.
5. The mileage listed in the County Road Logs is based upon slope distances measured using an odometer in a vehicle.  Mapping in the GIS uses horizontal projection distances. Therefore, the actual (on the ground) end of county maintenance will be a bit longer when compared to the same mileage measured in the GIS. The steeper the road, the greater the difference will be.  End of county maintenance is typically identified on the side of the road with a white paddle marker. 

Clicking on a road segment in the GIS will display the attributes for that road segment, which includes the State Road Number.  When a State Road Number that matches the format of a County Maintained Road number, then the road is potentially County Maintained. In the screen shot below, the State Road Number is 4L937. That is the County Road Number for Nursery Way. See the 2020/06/09 Road Numbering System Memo (below) for explanation on the format of the County Road Numbering System. 

above: screenshot from the County GIS showing the attribute table for a road segment; with emphasis on the State Road Number field.

A simple way to determine if a road is county maintained is to look for the yellow HUMCO sticker on a street name sign. This is 99% accurate. 

above: image of a street name sign showing the yellow HUMCO tab indicating that the road is County maintained.

New street name signs have the county logo on the left side of the sign in lieu of the yellow sticker.

above: image of a street name sign showing the County seal indicating that the road is County Maintained.

Caltrans is responsible for producing and publishing the California Road System Maps. Prior versions of these maps were better in identifying which roads are County maintained. The County's 1993 road maps are one of the best sources of maps available.

If you are not sure if a particular portion of a road is county maintained, you can email the Encroachment Permit Office with a google pin. Staff can research and report back to you.

In addition, most signs on the County Maintained Road System include a small while placard mounted below the sign. This placard identifies the road number and the approximate postmile of where the sign is located. The road number is written horizontally across two rows. The post mile is written vertically with the decimal portion of the post mile in superscript.

In the picture above for the stop sign at the Chantrelle Drive/Heartwood Drive intersection, the placard indicates that the road number is 4L991 and that the post mile of the sign is approximately at PM 0.33.

In the picture above for the stop sign at the Nursery Way/Heartwood Drive intersection, the placard indicates that the road number is 4L937 and that the post mile of the sign is approximately PM 0.28.

When contacting 911 for an incident on a county maintained road, providing the dispatcher with the post mile can speed up a response, especially on long roads.