Establish the governing local criteria and report revision, map catchments and proposed facilities to plan locations, then compare areas, elevations, pipe data and cited calculations. Route discrepancies and missing evidence to the civil engineer.
Establish the local review basis
Collect the current jurisdictional checklist, stormwater manual and application requirements. Record the project scope, permit basis and any accepted departures. Local requirements can change independently of the building-code cycle.
Seattle’s current stormwater page identifies a 2026 update effective July 1, 2026. Use its current source documents for a Seattle project rather than a saved draft or an older checklist. For another jurisdiction, replace those references with the applicable local sources.
Start with one drainage path
Select a catchment, its inlet or facility and the downstream outlet. Match the area label across the drainage exhibit, calculation and civil plan. Check the boundaries and surface assumptions before comparing discharge or storage values.
A report table can be internally consistent while describing an earlier site layout. Compare the documented geometry and elevations with the proposed grading plan and any architectural finished-floor interface.
A hypothetical elevation mismatch
Suppose the drainage report names one outlet invert while the current profile shows a different elevation for the same structure. Record the structure label and both source references. The civil engineer determines whether the report, profile or identification is superseded.
Check upstream inverts, storage geometry and receiving conditions after the decision. Do not revise hydraulic results or certify drainage capacity from a document discrepancy alone.
Drainage review worksheet
| Check | Sources | Review question |
|---|---|---|
| Applicable criteria | Local stormwater manual, application basis and checklist | Which requirements and edition govern this submission? |
| Catchment identity | Drainage map, report table and grading plan | Do labels and boundaries refer to the same contributing area? |
| Area and surface | Report assumptions, area table and proposed site plan | Are the stated areas and surface descriptions coordinated? |
| Storm basis | Narrative, calculation headings and local criteria | Do the stated storm events and assumptions agree? |
| Flow path | Grading plan, inlet layout and pipe profiles | Can each reviewed catchment be followed to its proposed receiving facility? |
| Pipe and structure data | Report tables, schedules, profiles and details | Do sizes, labels, inverts and elevations match? |
| Facility geometry | Storage calculations, sections and plans | Does the documented facility match the stated design geometry? |
| Review record | Civil response and revised report or sheets | Has the engineer resolved the mismatch in all affected sources? |
Keep the site-to-building interface
The civil and site checklist covers the wider package: utilities, grades, access and building service entries. Use it alongside this report-focused review so a drainage correction reaches the receiving building condition.
Include supporting geotechnical and survey information where the design relies on it. Identify an absent infiltration report or unclear datum as missing evidence, leaving engineering suitability to the responsible professionals.
Current primary source and review scope
Seattle SDCI stormwater code and manual is the primary reference for the Seattle example and links current submission material. Source checked October 13, 2026.
A report-to-drawing review can help surface inconsistencies in supplied documents. Your civil engineer verifies hydrology, hydraulics, assumptions and final submission requirements.