PondSheet
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Changelog

Each release, what changed, and whether it changes a result you already have. A project’s stored run never changes by itself: the project page says when the engine, data or rules moved and offers the re-run.

October 28, 2026

Reports, downloads and the reviewer page

  • PDF report from the stored server run: title block, contents, a page-one summary and the checks with the sources the engineer cited.
  • The report’s body: data provenance with the NRCS soils citation, the criteria, the inputs, results by storm, hydrographs and stage-storage-discharge, then the engineer-of-record statement and a blank seal block.
  • PRELIMINARY on every report page while any reference record is unverified.
  • Each report comes with its PDF, one SWMM 5 .inp per storm and the model JSON. A generated report never changes.
  • A read-only link for the plan reviewer with the same downloads, no account needed.
  • Firm settings, members and invites, check-set templates, export, billing, the trial and the read-only state.

Past results unchangedThe calculations did not change in this release.

October 28, 2026

Projects, the model workspace and your own criteria

  • Any US site. The engineer enters the criteria and the source for each; the NYSDEC design manual (July 31, 2024 and January 2015 editions) ships as a built-in template, and firms save their own.
  • Projects with a site pin and parcel, and NOAA Atlas 14 rainfall and USDA soils fetched once and frozen with the project.
  • The model workspace: sheets, paste from Excel or a Civil 3D report, undo, the engine running in the browser on every edit, the hydrographs and the checks.
  • Every NRCS WinTR-20 24-hr rainfall distribution, ten manufactured chamber systems, and the SWMM 5 .inp export, its format checked against the SWMM 5.2 manual and not yet run in SWMM.
  • 23 published worked examples, 612 compared values, on the validation page.

Past results unchangedThe first release with projects, so there were no earlier project results.

October 28, 2026

First release: the engine and five free calculators

  • The engine: TR-55 runoff, CN and Tc, the NRCS nested 24-hr site storm (NEH 630.04), the NRCS dimensionless unit hydrograph and the rational method.
  • Pond storage, HEC-22 and HDS-5 outlets, and storage-indication routing. The browser and the server run the same code and get the same bits.
  • Five free calculators: curve number and runoff, time of concentration, rational method peak flow, detention volume estimate, NY water quality volume.
  • Accounts, firms and invites, and the terms and privacy policy for Crux Labs LLC.

Past results unchangedFirst release.

How each result is checked against published examples is on the validation page.