Green Stormwater Infrastructure (GSI)

GSI cross section illustration annotated

Green stormwater Infrastructure (GSI) helps improve water quality, prevent flooding and replenish ground water. GSI uses specially engineered planted areas, filtration systems, and water permeable hardscapes to collect and clean water from roofs, streets, sidewalks, and other impervious surfaces.  California law requires GSI or other stormwater treatment for new and/or redevelopment projects over specified sizes, depending on the project type. 

Summary slides explaining GSI, City Staff Responsibilities and Resources

PowerPoint training slides November 14, 2025(PPTX, 21MB)

California State Water Resource Control Board GSI requirements

See section C.3 of the Municipal Regional Stormwater Permit (MRP)

Private development guidelines 

Is GSI required for my project?

For City of Oakland staff only:

Where’s GSI in Oakland?

GSI Plan - City of Oakland (2019) and Addendum (2024)

2019 plan for how the city of Oakland identifies, prioritizes, implements, tracks and reports green stormwater infrastructure (GSI) projects in Oakland.(PDF, 13MB)

The plan also promotes equitable geographic distribution of GSI in Oakland to improve human and watershed health, Bay fisheries, wildlife habitat, and aesthetics, and to lessen the negative impacts of climate change by adding vegetation and reducing runoff from severe weather.

2024 GSI Plan Addendum summarizes Oakland’s compliance with requirements updated in 2022 in the MRP 3, section C.3.j.ii.(1).(PDF, 375KB)

 

 

 

 

Technical documents - Design specifications, CAD files, delineation and sizing instructions, etc.

  1. (PDF, 2MB)City of Oakland GSI guide (2025) – introduces green stormwater infrastructure and describes why and when it is needed, how it works, and provides details on siting, selecting, sizing, and tracking facilities.(PDF, 32MB)
  2. Brief guide of GSI types(PDF, 1MB) (2025)
  3. GSI siting constraints annotated list – (utilities, building setbacks, bike lanes, etc.)(PDF, 142KB) (2025)
  4. GSI Drainage area delineation guide – why and how to map areas treated by GSI, and how to report into regional databases(PDF, 3MB) (2025)
  5. GSI instructions for City-hired consultants – guide to developing plan sets and completing plan checks from conceptual designs through 100% plans, and construction(PDF, 22MB) (2025)
  6. City of Oakland GSI technical design details and specifications(PDF, 4MB) (2025)
  7. CAD (Computer-Aided Design) files for GSI technical design details(ZIP, 11MB) (2025)
  8. C.3 Technical Guidance Manual (updated 2024) – Alameda Countywide guidance for GSI design requirements
  9. Guidance for Sizing (NON-REGULATED ONLY) Green Infrastructure Facilities in Street Projects (BASMAA)  

 

Plant species lists for GSI

GSI plant guide and list – species selection and procurement, propagation, irrigation, monitoring and maintenance(PDF, 590KB)

 

GSI Maintenance resources

City of San Jose GSI Maintenance Field Guide: Instruction, standards, and guidelines on inspection and maintenance of GSI projects. This is a good overview, though a simpler grading scale (good, moderate, poor) is recommended and a corresponding maintenance sheet has been developed.

 

As-builts for City GSI (available only to City of Oakland staff)

As-builts of completed City owned GSI (accessible by City of Oakland staff only)

 

Operations and Maintenance agreements for Privately Owned GSI

Coming soon - Accessible by City of Oakland staff only

 

Stormwater Management Resources Around Homes

 

Additional Resources

Alameda Countywide Clean Water Program Green Infrastructure website

 

Questions/comments

Contact Watersheds@oaklandca.gov

 

Back to top