Rapid Project Identification and Conceptual Design for Green Infrastructure Dan Cloak, P.E.April 8, 2015

Topics Using Google Maps to identify projects Desktop screening and conceptualization using Street View Project investigation –Utility information –Site reconnaissance and measurements Conceptual design process –Example and preliminary insights 8 Projects: Status and Next Steps

Watershed Scale (Map View) Old Urban –Street Grid Arterial Streets Old Industrial –Near water and rail –Large parcels

Subwatershed Scale (Satellite)

Desktop Screening (Street View)

Utilities

Site Reconnaissance

Conceptual Design

Alum Rock Ave. at Birch Lane 30 x x x x x x 290

Calculations Bioretention at low end30 x 30 =900 Tributary area X 25 =22,500 Alum Rock Avenue385 x 30 =11550 Frontage Street85 x 30 = Total Tributary Area14100 Next upgradient bioretention facility Birch Lane50 x Frontage Street43 x Total Tributary Area37470 Bioretention Area Required37470 x Length along 10-foot-wide median1500/10150

Alum Rock at Pleasant Ridge

Alum Rock At Pleasant Ridge 400 x x x x 500

Alum Rock at Pleasant Ridge

Summary: Alum Rock About 50,000 SF (1.1 acres) arterial roadway Additional 72,000 SF (1.6 acres) residential streets Plus portion of residential lots draining to street 3 bioretention facilities totaling about 5230 SF Need for traffic calming and pedestrian access

Some preliminary insights This is a craft Potential sites are easy to find –But are not available in all areas Subtle differences in elevation determine feasibility and cost Creating changes to surface drainage will be a key part of many projects –Overlays –Removing catch basins –Using trench drains

Eight Projects LocationType 1Alum Rock Ave.Arterial Street/Residential Streets 2Commercial St.Old Industrial Street and Facility Entrance 3Hedding StreetArterial - Disperse runoff to airport approach area 4San Felipe RoadSuburban Arterial 5N. 5 th St.Bioretention facilities in residential parkway strips 6St. James AlleywaysPermeable Pavement and Infiltration Trenches 7South Grant St., San Mateo Curb extensions/bulb outs in mixed-use area 8River Oaks Pump Station Divert dry weather and low flows to bioretention

Format for Work Product Rapid Project Identification & Conceptual Design –Methods and Applicability Section for each of eight projects –Detailed narrative description of design Issues, opportunities, potential conflicts Design considerations. proposed solutions Issues to be resolved in next design stage –Marked-up satellite photos Tributary areas (with dimensions) Facility footprints (with dimensions) Direction of flow, storm drain connections –Calculations for treatment or dispersal area –Site photographs –Concept-level cost estimates