Civil & Surveying ยท Contractor-Spec Deliverable ยท Pre/Post-Development ยท PDF + Markdown

Hydrology Report Generator

Generate a contractor-spec hydrology report PDF by combining your saved runoff calculations and inundation/scour results. Covers all 10 required sections: methodology, watershed definition, drainage patterns, stormwater rules, inundation maps, scour analysis, and the constraints discrepancy table. The deliverable the engineer hands to the contractor.

1Project Information
2Report Type
Sections included:
3Calculation Inputs
No saved runoff calcs found. Run the Runoff Calculator โ†’
No saved inundation calcs found. Run the Inundation & Scour tool โ†’
4Engineer Narrative (optional โ€” editable before stamping)

Leave blank to generate prompts; fill in before stamping. All text is included verbatim in the PDF.

Report sections (auto-generated unless noted)
1 Cover page โ€” project, date, engineer, revision
2 Modeling methodology โ€” SCS-CN, Rational Method, HEC-18
3 Drainage patterns Engineer editable
4 Stormwater rules & regulations Engineer editable
5 Upstream watershed definition โ€” from runoff calc
6 Historical drainage information Engineer editable
7 Onsite inundation levels โ€” 1-ft contour table
8 Scour analysis โ€” HEC-18, erodibility class
9 Supporting calculations appendix
10 Constraints Map discrepancies table
Methodology note
Runoff: SCS TR-55 CN method ยท Rational Method Q=CiA
Inundation: D8 flow accumulation + bathtub model
Scour: HEC-18 excess-shear ฯ„ = ฮณ_wยทdยทS vs ฯ„_c
Contour interval: 1 ft (0.3048 m)
Screening only โ€” not for construction without engineer review.

Frequently Asked Questions

What is in the report?+
The generated PDF covers all 10 sections required by the contractor hydrology report specification: (1) Cover page, (2) Modeling methodology, (3) Drainage patterns, (4) Stormwater rules, (5) Upstream watershed definition, (6) Historical drainage, (7) Onsite inundation levels (1-ft contour), (8) Scour analysis (HEC-18), (9) Supporting calculations appendix, and (10) Constraints Map discrepancy table. Sections 3, 4, 5, and 6 include engineer-editable free-text prompts.
What is the Post-Development report?+
The Post-Development report includes the same 10 sections as the Pre-Development report, plus two additional sections: (a) Anticipated stormwater management design โ€” describing detention/retention basin sizing, swales, culverts, and other BMPs; and (b) Changes to applicable stormwater management rules since pre-development. Both sections are engineer-editable before stamping.
What is the Markdown archive?+
Every generated report includes a Markdown (.md) download containing the full narrative text in plain format. The engineer can open this in any text editor, add or revise sections, then re-import it into their own document tooling. It ensures the narrative content is not locked inside the PDF.
What is NOT included (deferred)?+
The 72-hour post-storm drainage animation (MP4 video) required by some contractor specs is not included. That feature depends on a hydrograph animation engine and will be in a future release.