A faster front end for NC DEQ's SNAP v4.2.0 nutrient accounting workbook — the approved tool for stormwater compliance in the Tar-Pamlico, Neuse, Falls Lake and Jordan Lake nutrient strategy watersheds.
Enter land cover and SCMs once. TN and TP export rates, the project-area offset requirement, and SNAP's own error checks update as you type. Then download a completed SNAP workbook — your inputs written into DEQ's file with every DEQ formula left untouched, so what a reviewer opens is their tool, not a rebuild of it.
You supply your own copy of the workbook, from DEQ's Nutrient Practices and Crediting page. Everything runs in your browser — no upload, no account, nothing sent anywhere.
Independent tool. Not affiliated with, endorsed by, or reviewed by NC DEQ. The downloaded workbook is DEQ's — its formulas govern, and it recalculates itself when you open it in Excel. Export targets are set by your reviewing jurisdiction, not by this tool or by SNAP. Check the results and the workbook's own error messages before you rely on or submit anything. Provided as-is, without warranty; it does not constitute engineering advice and does not replace a licensed engineer's judgment. HydroComplete
1 · SNAP template
Load your own copy of SNAP Version 4.2.0.xlsx. Your inputs are written
into it and every DEQ formula is left untouched, so the file you download is DEQ's tool — not a
rebuild of it. Nothing leaves this machine.
2 · Project information
3 · Land cover areas in ft², pre- and post-project
4 · Stormwater control measures
5 · Results computed live; the downloaded workbook recalculates itself in Excel
6 · Least-cost search placeholder capital costs
Minimises SCM capital + nutrient offset purchase. Offset rates are real and sourced; SCM unit costs are placeholders until you load a real basis, so read breakeven $/ft³ — it is independent of them. Nutrient compliance only: this knows nothing about peak-flow control, ordinance minimums, or whether your jurisdiction allows a buy-down.
7 · Export
Runs entirely in your browser. Offset rates: NC DMS, effective .