The San Francisco Bay Regional Water Quality Control Board’s Municipal Regional Permit (MRP) requires jurisdictions to transition from gray, or piped, infrastructure storm drainage systems to green, or landscape-based, systems that capture, treat, and infiltrate runoff — Green Infrastructure. The County encourages project proponents to incorporate Green Infrastructure in project design.
The MRP defines Green Infrastructure as: Infrastructure that uses vegetation, soils, and natural processes to manage water and create healthier urban environments.
At the scale of a city or county, green infrastructure refers to the patchwork of natural areas that provides habitat, flood protection, cleaner air, and cleaner water. At the scale of a neighborhood or site, green infrastructure refers to stormwater management systems that mimic nature by soaking up and storing water. Examples of Green Infrastructure include:
- Stormwater Planters
- Stormwater Curb Extensions
- Rain Gardens
- Green Gutters
- Tree Well Filters
- Stormwater Trees
- Trees in the Landscape
- Infiltration Systems
- Pervious Pavement
- Green Roofs
- Green walls
- Rainwater Harvesting
- Vegetated Swales
Green infrastructure design should achieve three primary stormwater management goals: water quality improvement, flow reduction, and volume reduction. These interrelated goals help foster a balanced development condition that manages stormwater in a way that is closer to pre-development conditions.
- Webpage for Green Infrastructure on Flows to Bay
- The San Mateo Countywide Green Infrastructure Design Guide provides guidance regarding the design, implementation, and ongoing operations and maintenance of green infrastructure throughout communities in San Mateo County.
- San Mateo County’s Green Infrastructure Plan