Design and validate culverts in the browser.
FHWA HDS-5 sizing and hydraulic analysis, plus jurisdictional compliance checks (WSDOT AOP, WDFW, MS4, and more) with every governing equation shown. Built for civil, water-resources, and environmental engineers who need a fast, defensible answer.
Beta
Ongoing validation testing against FHWA HDS-5. Not for production use.
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Index of Tools
I
Design Workflow
Size a culvert, analyze hydraulic performance, and generate an engineering report.
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II
Multi-Scenario Analysis
Compare inlet types or run multiple design scenarios side by side.
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III
Calculation Explorer
Step through the FHWA HDS-5 methodology with interactive, real-time calculations.
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IV
Compliance Validation
Validate an existing culvert against jurisdictional criteria and produce a defensible report.
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V
Request a Custom Tool
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