California has corrected several predetermined wage increases in its 2026-1 prevailing wage determinations for public works. The Department of Industrial Relations reduced increases for multiple plumbing classifications effective September 1 and separately corrected apprentice-painter increases that took effect July 1.

The notices matter to awarding bodies, contractors, subcontractors, and payroll teams using Determination 2026-1 on covered public works. DIR's superseded-determination index says 2026-1 applies to projects advertised for bid from March 4 through August 31, 2026. The painter notice also names Determination 2025-2, which applies to projects advertised from September 1, 2025 through March 3, 2026.

The corrections do not establish one statewide hourly wage for every plumber or painter, and they do not replace Determination 2026-2 for projects advertised on or after September 1. The applicable amount still depends on the project, bid-advertisement timing, locality, craft, classification, shift, and, for apprentices, the worker's training period.

Apprentice plumber increases are lower than the earlier schedule

DIR's September 1 notice replaced a previously scheduled $4.03 increase for apprentice plumbers, pipefitters, and steamfitters in Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura counties.

For first-shift apprentices, the corrected increase is:

  • Period 1: $2.58 allocated to wages and/or fringes.
  • Period 2: $3.48 allocated to wages and/or fringes.
  • Period 3: $3.83 allocated to wages and/or fringes.

For second-shift apprentices, the notice lists $2.78 for Period 1 and $3.71 for Period 2, also allocated to wages and/or fringes.

The same corrected period amounts apply to apprentice plumbers, pipefitters, and refrigeration fitters in Inyo, Kern, and Mono counties. They also apply to apprentice air-conditioning and refrigeration service classifications in those three counties.

These figures are increases, not the employee's complete hourly package. Employers must apply them to the correct base determination and apprentice period rather than treating the notice amount as a standalone wage rate.

Landscape and irrigation classifications changed too

DIR also reduced the September 1 predetermined increase for landscape and irrigation plumbing classifications across Imperial, Inyo, Kern, Los Angeles, Mono, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura counties.

For a journeyman landscape or irrigation fitter, the scheduled $4.03 increase was replaced with $4.00: $3.10 to the basic hourly rate, $0.75 to health and welfare, $0.05 to pension, $0.05 to training, and $0.05 to other payments.

For a journeyman landscape or irrigation tradesman, the scheduled $2.07 increase was replaced with $0.57: $0.52 to the basic hourly rate and $0.05 to other payments.

The related apprentice amounts vary by shift and period. First-shift landscape and irrigation fitter apprentices receive increases of $3.45 in Period 1, $3.75 in Period 2, and $4.00 in Periods 3 through 5. Second-shift amounts are $3.67 in Period 1, $4.02 in Period 2, and $4.00 in Periods 3 through 5.

Service and repair plumbing increase is $3.94

For plumber and HVAC-fitter service-and-repair work in Imperial, Riverside, San Bernardino, and San Diego counties, DIR reduced the scheduled $4.03 increase to $3.94 effective September 1. The same $3.94 correction applies to the service-and-repair plumber classification in San Luis Obispo, Santa Barbara, and Ventura counties.

DIR allocated that increase as $3.01 to the basic hourly rate, $0.75 to health and welfare, $0.05 to pension, $0.05 to training, and $0.08 to other payments. The notice covers all shifts for the listed classifications and localities.

Apprentice painter amounts were corrected after July 1

On September 3, DIR corrected apprentice-painter predetermined increases that the department says were effective July 1 under the 2025-2 and 2026-1 determinations.

One table applies to Imperial, Orange, Riverside, San Bernardino, and San Diego counties and to Los Angeles County outside the Antelope Valley. Its first-shift basic-hourly-rate increases range from $1.13 in Period 1 to $1.71 in Period 8, with separate pension and vacation or holiday components. Second-shift basic-hourly-rate increases range from $1.28 to $1.92 across the eight periods.

A separate table applies to Inyo, Kern, and Mono counties and the Los Angeles County Antelope Valley. Its first-shift basic-hourly-rate increases range from $1.27 to $1.79, while second-shift increases range from $1.43 to $2.02. The published notice gives the exact pension and vacation or holiday allocation for every period.

Because the painter correction was published after its stated July 1 effective date, a covered contractor should compare payroll already processed against the corrected table and resolve any discrepancy using the governing determination and official DIR guidance. The notice itself does not provide a payroll-adjustment procedure.

What did not change

Each notice says the wage rates and conditions outside the identified modifications or corrections remain unchanged. The notices do not replace the full prevailing wage determination, change every plumbing or painting classification, or say that the listed increases apply to private construction generally.

California's regulatory definition of a predetermined change also addresses a contractor's obligation when a published increase is modified before its effective date. That provision can affect how an existing public works contract handles a reduction. Federal Weekly is not treating the new notice as authorization to recover wages already paid or to ignore a higher amount incorporated into a contract. A contractor should resolve that question with the awarding body or DIR for the specific project.

The September 1 date is recorded on Federal Weekly's compliance calendar, and the corrections are indexed in the Business Rule Change Tracker.

The practical takeaway

An awarding body or contractor using California Determination 2026-1 should stop relying on a previously downloaded increase sheet without checking the current important-notice index. Match each worker to the project's controlling determination, locality, craft, classification, shift, and apprentice period, then apply the corrected increase to the proper wage and fringe components.

Payroll teams should pay particular attention to work performed on or after September 1 under the affected plumbing classifications and to apprentice-painter payroll tied to the corrected July 1 amounts. Preserve the notice used for the calculation and contact DIR's Office of the Director Research Unit when the project's advertisement date or classification makes applicability unclear.