Low Impact Development (LID)

Humboldt LID Stormwater Manual V3.0

Under direction from the Regional Water Board, the North Coast Stormwater Coalition has updated the LID manual to be consistent with the Statewide MS4 permit. These alterations include changing ASTM (American Society for Testing and Materials) standards and requirements from the state, specifically in regards to the statewide stormwater order under the Construction General Permit. The most impactful update in Version 3 of the LID manual is that Infiltration Trenches/Basins/Subsurface Infiltration devices are no longer applicable as credited site design measures. Furthermore, details have been added to the manual concerning hydromodification and testing protocols. The LID manual link below has been updated to the most recent version and reflects these changes in green throughout the document.

Manual and all appendices (excluding CASQA BMP sheets)

Click image to download PDF of the LID Manual

(link to download PDF) Caution large file size

Small Projects Calculator V3.0

(link to download Excel Workbook)

Regulated Projects Worksheets V3.0

(link to download Excel Workbook)Click to download Excel Workbook

CASQA Pollutant Source Control BMP Sheets

(link to download BMP Sheets) Caution large file size

Click to download BMP Sheets
Click image to download BMP Sheets

Resources for LID and

Ocean Friendly Gardens

LID Plant List

LID Site Design Measures