South Dakota Prevailing Wage Project Cost Calculator
Estimate total labor costs for South Dakota prevailing wage (Davis-Bacon equivalent) public works projects, including base wages, fringe benefits, employer payroll taxes, overhead, and profit markup.
Formulas Used
Regular Base Wages = Base Wage Rate × Regular Hours (≤40/wk) × Workers × Weeks
Overtime Base Wages = Base Wage Rate × 1.5 × OT Hours × Workers × Weeks
Fringe Benefits = Fringe Rate × Total Hours (reg + OT) × Workers × Weeks
Gross Labor = Regular Base Wages + Overtime Base Wages + Fringe Benefits
Employer Payroll Taxes = (Regular + Overtime Base Wages) × Payroll Tax Rate
Total Labor Burden = Gross Labor + Employer Payroll Taxes
Overhead = Total Labor Burden × Overhead Rate
Cost Before Markup = Total Labor Burden + Overhead
Profit Markup = Cost Before Markup × Markup Rate
Total Bid Price = Cost Before Markup + Profit Markup
All-In Cost per Hour = Total Bid Price ÷ Total Hours
Assumptions & References
- South Dakota follows federal Davis-Bacon Act prevailing wage requirements for federally funded public works projects (contracts ≥ $2,000). SD does not have a separate state prevailing wage law as of 2024.
- Wage rates shown are illustrative examples based on U.S. Department of Labor Wage Determinations for South Dakota (WD General Decision SD20240001 series). Always verify current rates at SAM.gov or the DOL Wage Determinations Online portal.
- Overtime is calculated at 1.5× the base wage rate per the Fair Labor Standards Act (FLSA) for hours worked over 40 in a workweek.
- Fringe benefits are paid at the straight-time rate on all hours worked (regular and overtime), per Davis-Bacon regulations (29 CFR Part 5).
- Employer payroll taxes are applied to base wages only (fringe benefit contributions are not subject to FICA/FUTA/SUTA).
- Typical employer payroll tax rate: FICA 7.65% + FUTA 0.6% + SD SUTA ~1.0% ≈ 9.25% (SD SUTA rate varies by employer experience rating; see SD Department of Labor & Regulation).
- This calculator covers labor costs only. Material, equipment, subcontractor, bonding, and insurance costs must be added separately.
- Certified payroll records are required for all Davis-Bacon covered projects (WH-347 form).
- Contractors must post the applicable wage determination at the job site (29 CFR § 5.5(a)(1)).
Federal and state construction contracts in South Dakota carry mandatory wage floors that can increase total labor costs by 15–40% above standard market rates, depending on trade classification and county. Contractors who miscalculate these obligations face back-wage liability, debarment from future federal work, and contract termination under 40 U.S.C. § 3141. Accurate project cost estimation therefore begins with prevailing wage determination, not after it.
What Is a Prevailing Wage?
A prevailing wage is the minimum hourly rate — including fringe benefits — that contractors and subcontractors must pay workers on covered public construction projects. At the federal level, the Davis-Bacon and Related Acts establish this requirement for any federally assisted construction contract exceeding $2,000. The rate is not a single statewide number; it is occupation-specific, project-type-specific, and geographically bounded, typically at the county level.
South Dakota does not have a standalone state prevailing wage law equivalent to Davis-Bacon. Title 60 of the South Dakota Legislature governs general labor and employment standards in the state, but it does not independently mandate prevailing wages for state-funded contracts. Projects receiving federal funding in South Dakota are therefore governed exclusively by the federal Davis-Bacon framework and the wage determinations published through SAM.gov.
How Federal Wage Determinations Are Structured for South Dakota
The U.S. Department of Labor Wage and Hour Division issues wage determinations by project type across four primary construction categories:
- Building construction — commercial and institutional structures
- Residential construction — single-family and multi-unit housing
- Heavy construction — dams, bridges, highways, utility infrastructure
- Highway construction — roads, runways, parking lots
Each wage determination lists craft classifications (e.g., Carpenter, Electrician, Ironworker, Laborer) alongside a base hourly rate and a fringe benefit rate. The combined figure — base plus fringe — constitutes the total prevailing wage rate. Under 20 CFR § 655.10, fringe benefits may be paid in cash or through bona fide benefit plans; if paid in cash, the full fringe amount is added to the worker's gross hourly wage.
South Dakota spans multiple wage determination jurisdictions. Minnehaha County (Sioux Falls metro) and Pennington County (Rapid City metro) routinely carry different rates from rural western counties like Haakon or Ziebach. Always retrieve the active SAM.gov wage determination for the specific county and project type before beginning cost modeling.
Calculator Inputs
A South Dakota prevailing wage project cost calculator requires the following discrete inputs:
| Input | Description |
|---|---|
| Project county | Determines which SAM.gov wage determination applies |
| Project type | Building, residential, heavy, or highway |
| Labor classification | Trade or craft category from the applicable wage determination |
| Base hourly rate | Dollar figure from the SAM.gov determination for that classification |
| Fringe benefit rate | Per-hour fringe from the determination (e.g., $8.42/hr for a specific Carpenter rate) |
| Estimated labor hours | Total hours per classification across project duration |
| Number of workers | Headcount per classification |
| Overtime multiplier | Federal overtime applies at 1.5× base rate; fringe benefits do not multiply |
Core Calculation Formula
For each labor classification, the prevailing wage labor cost follows this structure:
Straight-Time Cost = (Base Rate + Fringe Rate) × Straight-Time Hours × Workers
Overtime Cost = ((Base Rate × 1.5) + Fringe Rate) × Overtime Hours × Workers
Total Labor Cost (per classification) = Straight-Time Cost + Overtime Cost
Project total labor cost is the sum across all classifications. This figure feeds directly into certified payroll reporting requirements, which contractors must submit weekly on Davis-Bacon projects (according to DOL Wage and Hour Division).
Benchmarking Against BLS Occupational Wage Data
The Bureau of Labor Statistics Occupational Employment and Wage Statistics (OEWS) program publishes annual mean and percentile wages for South Dakota by occupation. These figures serve as a sanity-check baseline. If a SAM.gov prevailing wage determination for Electricians in Lawrence County shows $32.50/hr base, and BLS OEWS data for South Dakota Electricians shows a median around $28–$30/hr, the prevailing wage premium is quantifiable and expected. A determination that falls significantly below BLS median rates may indicate an outdated wage determination — contractors should verify the determination's effective date on SAM.gov before using it.
The South Dakota Department of Labor and Regulation publishes supplementary labor market information for the state, which project planners use to validate workforce availability alongside wage cost modeling.
Sample Calculation: Heavy Construction Project, Pennington County
Assume a federal-funded bridge project in Pennington County using the current heavy construction wage determination:
- Classification: Operating Engineer, Group 3
- Base rate: $38.75/hr (hypothetical placeholder — retrieve actual from SAM.gov)
- Fringe rate: $14.20/hr
- Workers: 4
- Straight-time hours per worker: 480
- Overtime hours per worker: 60
Straight-time cost: ($38.75 + $14.20) × 480 × 4 = $101,664 Overtime cost: (($38.75 × 1.5) + $14.20) × 60 × 4 = $48,519 Total for this classification: $150,183
Multiply this across 6–12 trade classifications typical on a bridge project, and total prevailing wage labor exposure reaches $900,000–$1.8 million before materials, equipment, or overhead.
Certified Payroll and Compliance Obligations
Every contractor and subcontractor on a Davis-Bacon project must submit weekly certified payroll using DOL Form WH-347 (according to the DOL Wage and Hour Division). The form documents each worker's name, classification, hours worked, gross wages, deductions, and net pay. Intentional falsification of certified payroll records constitutes a federal violation under 18 U.S.C. § 1001 (according to Cornell Legal Information Institute). Debarment periods for willful violations typically run 3 years (according to the DOL Wage and Hour Division).
FAQ
Does South Dakota have its own prevailing wage law separate from Davis-Bacon?
No. South Dakota does not maintain an independent state prevailing wage statute. Projects in South Dakota fall under the federal Davis-Bacon framework when federal funding is present. Title 60 of the South Dakota Legislature covers general employment law but does not independently mandate prevailing wage floors for state contracts.
Where are South Dakota county-level wage determinations published?
Active wage determinations are published on SAM.gov, searchable by state, county, and construction type. Determinations are updated periodically; contractors must use the determination in effect at the time of contract award.
Are fringe benefits included in overtime calculations?
No. Under Davis-Bacon rules, the overtime premium (0.5× base rate) applies only to the base hourly rate, not the fringe benefit portion. Fringe benefits are paid at the straight-time rate regardless of total hours worked (according to the DOL Wage and Hour Division).
What is the minimum contract threshold that triggers Davis-Bacon requirements?
The threshold is $2,000 for federal or federally assisted construction contracts, as established under 40 U.S.C. § 3141.
How does the calculator handle multiple subcontractors on a single project?
Each subcontractor is treated as a separate compliance entity. The calculator aggregates labor costs across all classifications and contractors. Each subcontractor must independently submit certified payroll and ensure their workers receive no less than the applicable prevailing wage determination rate.