I took the text of this page from the presentation given at a Town Council meeting on April 15, 2026, by Alejandro Perez, Senior Civil Engineer in Public Works.
Background:
There are two categories for setting speed limits by the California Vehicle Code (“CVC”). Speed limits can be established by default speed (“Prima Facie”) or by an Engineering & Traffic Survey (“E&TS”). The Town of Windsor is authorized by California Vehicle Code Section 22357 to adjust speed limits above the Prima Facie limit by ordinance after conducting an E&TS. An E&TS must be re-evaluated periodically, generally every 5 to 7 years and may be extended up to 14 years from the date of the original certification. Windsor’s most recent evaluation for several segments of Town Streets was completed in 2024.
While no current speed limits were due to expire, this review cycle focused on implementing the recent changes in State Law that have been enacted as a result of Assembly Bill (“AB”) 43, AB 1938, and AB 382, which have created more flexibility for local agencies to lower speed limits. Namely, this effort focused on implementing the following three key changes.
Business Activity Districts: AB 43 authorizes local agencies to establish prima facie speed limits of 25 miles per hour or 20 miles per hour in designated Business Activity Districts.
Reduced School Zone Speeds: As authorized by AB 382, speed limits of 15 or 20 mph are now permitted in school zones within 500 feet of school grounds when certain conditions are met. Additionally, 25 mph school zone speed limits may be implemented up to 1,000 feet from school grounds in select conditions.
High Concentrations of Bicyclists or Pedestrians: As authorized by AB 1938, an additional 5 mph from the 85th percentile speed is permitted in speed zones that are adjacent to land uses or facilities that generate high concentrations of cyclists or pedestrians.
The Public Works Department, together with the Police Department, have undertaken an update of the Town’s posted speed limits by conducting new Engineering and Traffic Surveys (E&TS) where required for street segments that may qualify for a Business Activity District designation, reduced or extended school zone speed limit, or a reduction for having high concentrations of bicyclists and pedestrians. When E&TSs are completed in conformance with applicable State of California requirements and the Town Council adopts the recommended speed limits, Town police can use radar as a speed enforcement tool.
Fiscal Impact:
Sufficient appropriations are included in the Fiscal Year 2025-2026 Gas Tax Fund to update the necessary speed limit signs.
Discussion:
A new E&TS was conducted for 10 street segments that were potentially eligible for an additional 5-mph reduction due to proximity to land uses that generate high concentrations of bicyclists and pedestrians. Of these 10 segments, nine are recommended for speed limit reductions and/or boundary segment changes.
The segment of Windsor Road between Windsor River Road and Joe Rodota Drive was reviewed and determined to meet the requirements for a Business Activity District; therefore, a speed limit reduction from 25 to 20 mph is recommended. This would become the Town’s first official Business Activity District.
All eight existing school speed zones in Town were reviewed for potential reductions and all eight zones are recommended to be reduced from 25 to 20 mph.
For purposes of the discussion below, the 85th percentile speed is the speed at which 85 percent of motorists are traveling at or below. Speed limits are usually set near this speed with reductions allowed for specific conditions; however, cannot be set more than 12.4 mph below the 85th percentile speed. The Pace speed is the 10-mph range which contains the most vehicles and is a key consideration when setting speed limits to facilitate the orderly movement of traffic.
The street segments that are recommended by Town staff for speed limit changes and/or revised boundaries are described below and summarized in the following table.
The Brooks Road South segment between Arata Lane and Lakewood Drive is recommended to be divided into two separate segments given the difference in configuration and adjacent land uses. The first segment, from Arata Lane to Foothill Drive (existing 35 mph), has a calculated 85th-percentile speed of 36, with the nearest 5-mph increment of 35. However, a reduction to 25 mph is recommended in consideration of pedestrian safety and due to the presence of a school which generates high concentrations of pedestrians and bicyclists. The second segment, from Foothill Drive to Lakewood Drive (existing 35 mph), has a calculated 85th-percentile speed of 38, with the nearest 5-mph increment of 40. A reduction to 30 mph is recommended due to the presence of several land uses that generate high concentrations of pedestrians and bicyclists, including a senior housing complex, commercial uses, and a park.
The Conde Lane segment between Oakfield Lane to Mitchell Lane (existing 40 mph) has a calculated 85th-percentile speed of 47 mph, with the nearest 5 mph increment of 45 mph. A reduction to 35 mph is appropriate given that facilities for pedestrians and bicyclists are discontinuous and the RV park and mobile home park generate high concentrations of pedestrians and bicyclists.
The Hembree Lane segment between Jensen Lane and Old Redwood Highway (existing 40 mph) has a calculated 85th-percentile speed of 44 mph, with the nearest 5-mph increment of 45 mph. However, a reduction to 35 mph is recommended in consideration of the pace and due to the presence of an adjacent senior living development which generates high concentrations of pedestrians and bicyclists.
The Old Redwood Highway segment between Windsor Road and Windsor River Road (existing 30 mph) has a calculated 85th-percentile speed of 36 mph, with the nearest 5 mph increment of 35 mph. However, a reduction to 25 mph is recommended due to the presence of back-in parking, frequent pedestrian crossings, and several lane uses including the Town Green that generate high concentrations of pedestrians and bicyclists, especially during events.
The Pleasant Avenue segment between Old Redwood Highway and the eastern Town limits (existing 35 mph) has a calculated 85th-percentile speed of 37 mph, with the nearest 5 mph increment of 35 mph. A reduction to 30 mph is recommended due to the presence of young students from the elementary school who have little awareness for safe traffic practices.
The Starr Road segment between Old Redwood Highway and Windsor River Road (existing 35) has a calculated 85th-percentile speed of 38 mph, with the nearest 5-mph increment of 40 mph. However, a reduction to 30 mph is recommended due to the gaps in the bicycle and pedestrian network and the presence of multiple schools which generate high concentrations of pedestrians and bicyclists. The area just north of Gumview Road is also anticipated to see increased pedestrian and bicycle activity with the planned multi-use path as part of Sonoma-Marin Area Rail Transit (SMART)’s extension to Healdsburg.
The Windsor River Road segment between Starr Road and Windsor Road (existing 35) has a calculated 85th-percentile speed of 39, with the nearest 5mph increment of 40 mph. A reduction to 30 mph is appropriate due to the pace and in consideration of Keiser Park near the middle of the segment which generates high concentrations of pedestrians and bicyclists.
The Windsor Road segment between Windsor River Road and Mitchell Lane (existing 35 mph) has a calculated 85th-percentile speed of 38, with the nearest 5mph increment of 40 mph. A reduction to 30 mph is recommended in consideration of the safety in inexperienced student drivers and due to the presence of the high school which generates high concentrations of pedestrians and bicyclists.
The Windsor Road segment between Windsor River Road and Joe Rodota Drive (existing 25 mph) meets the Business Activity District classification as described in California Vehicle Code Section 22358.9, and is therefore eligible for a reduced speed limit to 20 mph. A reduction to 20 mph is recommended due to the narrow streetscape, parallel parking, on-street dining areas, and high commercial activity along this segment.
Six school zones, consisting of eight total street segments, also qualified for speed limit reductions to 20 mph. Three of these segments – Natalie Drive, Foothill Drive, and Sugar Maple Drive – qualified for reductions to 15 mph given that they are in residential districts, as defined by the CVC. Town staff recommends reducing all the school zone segments to 20 mph at this time to maintain consistency with implementation and messaging to the community, and assessing the need to further reduce the segments that qualify for 15 mph at a future date.
Based upon the updated E&TS and current State Law, it is recommended that their speed limits and/or boundary changes be posted as summarized in the following table.
| Street | Segment Boundaries | Posted Speed Limit | Proposed Speed Limit |
|---|---|---|---|
| New Surveys | |||
| Brooks Road South | Arata Lane to Foothill Drive | 35 | 25 |
| Brooks Road South | Foothill Drive to Los Amigos Road | 35 | 30 |
| Conde Lane | Oakfield Lane to Mitchell Lane | 40 | 35 |
| Hembree Lane | Jensen Lane to ORH | 40 | 35 |
| Old Redwood Highway | Windsor Road to Windsor River Road | 30 | 25 |
| Pleasant Avenue | ORH to Town Limits East | 35 | 30 |
| Starr Road | ORH to Windsor River Road | 35 | 30 |
| Windsor River Road | Starr Road to Windsor Road | 35 | 30 |
| Windsor Road | Windsor River Road to Mitchell Lane | 35 | 30 |
| Business Activity District | |||
| Windsor Road | Windsor River Road to Joe Rodota Drive | 25 | 20 |
| School Speed Zones (When Children are Present) | |||
| Starr Road (WCA) | ORH to Belfiore Lane | 25 | 20 |
| Starr Road (Cali) | Robbie Way to Windsor River Road | 25 | 20 |
| Natalie Drive (Brooks) | Biggs Way to Trail Crossing | 25 | 20 |
| Brooks Road South (WMS) | Jessica Drive to Foothill Drive | 25 | 20 |
| Foothill Drive (WMS) | Brooks Road South to Esparto Court | 25 | 20 |
| Windsor Road (WHS) | Duncan Drive to Winemaker Way | 25 | 20 |
| Sugar Maple Lane (Mattie) | Shadetree Drive to Quince Street | 25 | 20 |
| Pleasant Avenue (Mattie) | ORH to Emerson Street | 25 | 20 |
Town staff recommend a two-phase approach for installing the new speed limit signage. In the first phase, the Public Works Department would install all permanent speed limit signage during the spring, including advance warning signs to notify motorists of upcoming changes and allow an acclimation period. A second phase would include the installation of 20 mph speed limit signage for school zones over the summer break, allowing the Police Department to conduct an education campaign ahead of the 2026-2027 school year. Because Windsor has not previously had 20 mph speed limits, these signs may be unfamiliar to drivers; LED-enhanced signage would be used to alert drivers in the short term and improve long-term recognition and compliance with school zone speed limits.
Members of the Town Traffic Safety Committee, including Public Works and Police representatives, support the updated survey results and associated E&TS, as the use of radar as a speed enforcement tool is essential to maintaining safe traffic operation in Windsor.