Transportation Infrastructure
Why Transportation Infrastructure Matters for San Joaquin County?
86.4%
of major locally-owned roads (not including interstates) are in Fair condition, 4.7% are in Good condition, and 8.9% are in Poor condition. Statewide, 53% of major roads are rated Fair and 45% are rated Good.
265.0 lane-miles
Stockton’s locally owned National Highway System pavement in 2023: 1.3% rated Good, 94.4% Fair and 4.3% Poor. The locally owned National Highway System in San Joaquin County, including city-owned roads, comprised 612.0 lane-miles in 2023. Of that pavement, 7.8% was rated Good, 87.1% Fair and 5.1% Poor.
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San Joaquin County’s average Pavement Condition Index in 2025, down from 68 in 2022, on a scale from 0 (failed) to 100 (excellent). This measure covers locally maintained roads throughout the county, including its cities, and weights pavement conditions by pavement area. It covers a broader local road network than the separate National Highway System pavement indicator.
Transportation Infrastructure
Inventory and Conditions of Local NHS Pavements
This indicator provides a measure to assess the quality of 564.4 miles of major locally-owned pavement on the National Highway System (NHS) (excluding the Interstate System) in San Joaquin County.
86.4%
of 564.4 miles of locally-owned pavement on the National Highway System (NHS) (excluding the Interstate System) in San Joaquin County is in Fair condition, with 4.7% in Good condition and 8.9% in Poor condition. With regard to California’s 36,896 miles of pavement overall, 45% is in Good condition, with 52.8% in Fair condition and 2.3% in Poor condition.
Definition - NHS Pavement
San Joaquin County pavement condition indicator data includes the roads and bridges (as federally defined) in the National Highway System (NHS) that are critical to national and regional connectivity, not the broader local road network. The data excludes residential streets, minor collectors, and rural local roads not on the NHS.
Caltrans uses performance measures for condition ratings of National Highway System (NHS) pavements. These performance measures are calculated based on data reported in the Highway Performance Monitoring System (HPMS). The four measures are calculated using quantitative data on the following metrics:
1. Pavement roughness, an indicator of discomfort experienced by road users traveling over pavements, is measured using the International Roughness Index (IRI).
2. Rutting is quantified for asphalt pavements by measuring the maximum depth of undulation transversely along the wheel path. Rutting is commonly caused by a combination of slow moving traffic and heavy vehicles or insufficient underlying support.
3. Cracking is measured in terms of the percentage of cracked pavement surface. Cracks can be caused or accelerated by excessive loading, poor drainage, moisture or temperature changes, material issues, and construction flaws.
4. Faulting is quantified for concrete pavements as the height difference across transverse joints or cracks. Faulting occurs when there is heavy vehicle loading, slab curling, erodible base material, and water present that cause independent slab movement.
For each of the above metrics, thresholds for good, fair, and poor condition have been established by the federal transportation act. The pavement condition metrics are used to calculate Federal Highway Administration (FHWA) performance measures for pavement condition. Conditions are assessed using these criteria for each 0.1-mile-long pavement section. An individual section is rated as being in good overall condition if all of the metrics are rated as good, and poor when two or more are rated as poor. All other combinations are rated as fair. Lane miles in good, fair, and poor condition are tabulated for all sections to determine the overall percentage of pavement in good, fair and poor condition. For the NHS, overall pavement condition is based on outer lane distresses only. Lane miles is the centerline length (in miles) multiplied by the number of lanes. Lane miles is a more complete metric of pavement surface because it reflects the area of the pavement and is used for calculating performance measures and targets.
The majority of local jurisdictions in California utilize an alternative performance measure called the Pavement Condition Index (PCI) to measure pavement condition. PCI is a numerical index between zero and 100 used to indicate the general condition of a pavement section but excludes the pavement roughness required in the FHWA performance metric.
For details, see Caltrans Asset Management Plan 2022.
Pavement Condition Index Trend in San Joaquin County
The Pavement Condition Index (PCI), reported in the California Statewide Local Streets and Roads Needs Assessment, is based on a survey of local jurisdictions. It reflects the average condition of all locally maintained roads, including residential streets, collectors, and arterials managed by both cities and the county. Rated on a scale from 0 (failed) to (excellent), the PCI attempts to provides a comprehensive snapshot of pavement conditions across San Joaquin County’s local road network.
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San Joaquin County’s average Pavement Condition Index in 2025, down from 68 in 2022, on a scale from 0 (failed) to 100 (excellent). This measure covers locally maintained roads throughout the county, including its cities, and weights pavement conditions by pavement area. It covers a broader local road network than the separate National Highway System pavement indicator.
For further details on the PCI methodology and definitions see:
Bridge Condition Ratings in San Joaquin County
The 2025 assessment identifies 342 locally owned public-road bridges in San Joaquin County, including bridges owned by cities and the county. Of these, 140 (40.9%) were rated Good, 172 (50.3%) Fair and 30 (8.8%) Poor. Together, 202 bridges (59.1%) were rated Fair or Poor. These percentages count bridges and are not weighted by deck area.
59.1%
Of San Joaquin County’s locally owned public-road bridges were rated Fair or Poor in the June 2025 inventory.
Definition - Bridge Condition
The California Local Bridge Needs Assessment Report (2025) includes all locally owned public road bridges, regardless of functional classification or National Highway System (NHS) designation, whereas the NHS bridge data only covers bridges located on the NHS, focusing on those critical to national mobility and subject to federal performance reporting requirements.
The National Bridge Inventory (NBI) data used in this indicator is current through June 15, 2025. The detailed bridge information is based on a snapshot in time of the recorded bridge inspection most up to date at the time the data was taken from the database.
For purposes of this data, a bridge is defined as “a structure including supports erected over a depression or an obstruction, such as water, highway, or railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening.”
The data tracks a variety of metrics related to the age, type, condition, and function of the bridge. Generally, the NBI data used include condition for Deck, Superstructure, Substructure, Structural Evaluation, Deck Geometry, Bridge Posting and Scour. Geometrical information and bridge age determined using Year Built were also taken from the NBI data. Based on definitions from the Federal Highway Administration (FHWA), bridge condition and performance are categorized as “Good”, “Fair”, or “Poor”. These labels are based on condition ratings of the bridge’s Superstructure, Substructure, and Deck components on a scale of 0 through 9 which are evaluated and assigned every 2 years during the biennial bridge inspection process.
For details, see Local Bridge Needs Assessment, Table 3.3 (2025)