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Work Zone Safety Information Clearinghouse

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Practice

Work zone impact thresholds

WSDOT does not use performance specifications. Time of day restrictions or night work is specified based on hourly traffic volumes. Generally WSDOT uses analysis programs such as QUEWZ98 to calculate queue lengths, delay, and user costs to establish work hour restrictions and any applicable liquidated damages. Enforcement in the field is typically by WSDOT field inspectors for contract work.

State/Agency: Washington
Topics: Lane Closure; Traffic Delays

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