A demonstration project for site-scale “Green Infrastructure”

1. Alhambra Headquarters Parking Lot Demonstration Project A demonstration project for site-scale “Green Infrastructure” Thomas Tidemanson Headquarters Building

2. South Parking Lot Panorama Main entrance for visitors is subject to heat and glare.

3. West Parking Lot Panorama West parking lot has shaded area preferred by most employees.

4. East Parking Lot Panorama Unshaded parking lot. Typical of many office and commercial landscapes.

5. Charrette Performance Objectives • Potable water conservation - Reduce irrigation by 60% • Flood Control • Retain/Treat the first 3/4” of rain • Retain 10-yr design storm • Retain 50-yr capital storm • Mitigate non-point source stormwater pollution • Energy conservation - Eliminate as much reflected light from parking lot as possible • Skin Cancer - Reduce direct sun exposure as much as possible • Green waste - Retain all green wastes on-site • Air Pollution - Provide 75% shade cover to parked cars • Education - Monitor all systems, describe for the visitor, and inspire other potential implementers

6. Team 1 • Karen Wolfe • Vik Bapna • Andy Lipkis • Steve Burger • Jim Daly • Patrick Condon • Stacy Moriarty Team 1 in discussion at 9:00 a.m.

7. Team One Performance Objectives • Flood Control: Reduce peak flows and volumes from the site, thereby lessening the burden on flood control system • Stormwater Pollution: First-flush and non-point source pollution treated using as many recommended BMPs as possible • Energy Conservation: Substantially reduce urban heat island effect by shading 75% of parking lot with tree canopy • Skin Cancer: Drastically reduce human exposure to sun by providing direct shade of parking areas and walking paths • Green Waste: Capture 100% on site • Air Pollution: Urban Forest in parking lot to shade 80% of parked cars • Education: Monitor: Monitor all systems for performance and maintenance data. Describe: Use site to describe function of systems. Inspire: Show how a sustainable landscape can be a more beautiful landscape

8. • Foresting the site • Storage Tanks for storm- water retention and recycling • Above-grade cisterns on ground or on roof • Permeable Pavement for Infiltration • Dry Ponds and Dry Swales for retention, infiltration and creation of different ecological/hydrological niches • Dry well for monitoring and demonstration purposes • Catch Basin inserts for monitoring • Biofiltration/ Infiltration trenches • Solar Voltaics in re-glazing project • Wetpond for visual amenity, demonstration and biofiltration • Graywater use on site Team OneBMP list

9. Site Drain System Schematic DRY ZONE The parking will be rearranged to allow 8.5’ wide diagonal spaces. Medians will be added and will include a vegetated swale with an infiltration trench. Water will flow in the swale only during storm events. Xeriscaping will be installed throughout this zone. INTERMITTENT ZONE A median will be constructed and will include a vegetated swale with an infiltration trench. Water will flow intermittently, assisted during dry days with a pump. Water will be provided from collected rain runoff and supplemented from the stored water supply. Drought tolerant plants will be used in this area. WET ZONE A wetland will be constructed to act as a bio-retention facility. The water will be replenished as necessary from the cistern in the southwest corner and supplemented from the water supply during extended dry periods. A wide range of hydrological niches will be found in this area. The site is divided into Dry Zone, Intermittent Zone and Wet Zone BMPs

10. East Parking Area • Provide diagonal parking spaces. Increase size by 1 ft. • Decrease admin. spaces by .5 ft. to gain room for new handicapped parking • Provide permeable test surfaces • Include additional trees on median • Add vegetated swale w/infiltration trench East parking area is redesigned for increased efficiency and ecological performance

11. Constructed Wetland Edge along Fremont Avenue • Replant edge of Fremont with tall trees to produce optimum shade in west parking area • A linear constructed wetland is used to provide physical, chemical and biological water quality treatment • A variety of plant species are proposed based on available water A constructed wetland runs parallel to Fremont Avenue

12. West Parking Lot • Reconfigure parking to increase space • Relocate handicapped spaces • Add trees to each row • Add 15’ wide bioremediation aisle West parking lot reconfigured for greater efficiency and ecological performance

13. Vegetated Filter Strip with Infiltration Trench & Shade Trees • Surface runoff is collected and treated in 5’ wide vegetated filter strips • Infiltration trenches are located under all vegetated filter strips • Shade trees are planted 18’ on center throughout the parking lot • A variety of porous pavements are used in the parking bays. Different pavement materials and strategies are demonstrated and monitored throughout the site Vegetated filter strips with infiltration trenches and shade trees are located in the parking lot medians

14. Team 2 • Nelson Nelson • Mike Soliman • Mie Joness • Marty Moreno • Rossana D’Antonio • Michael Drennan Team 2 in discussion at 9:00 a.m.

15. PERFORMANCE OBJECTIVES • Potable water conservation • Recycle stormwater for 75% irrigation by utilizing cistern • Replace existing plants with drought-tolerant California native plants (e.g. replace existing grass with buffalo grass or uniform ground cover) • Flood Control • Retain 3/4” by utilizing infiltration trenches, cistern, porous paving • It appears a 50-yr storm can be retained in areas where porous pavement is used, based on known soil conditions and manufacturers’ claims • Stormwater Pollution • Filter stormwater by infiltration trenches • Provide settling tank upstream of cistern

16. PERFORMANCE OBJECTIVES • Energy Conservation • Eliminate reflected light from parking surface by planting trees for shade • Provide shade/solar panel for the EVs • Skin Cancer • Reduce ultraviolet light by planting trees • Provide added shade area by installing trellis with vines (e.g. at building entry area above courtyard) • Green Waste • Provide compost/green waste recycle area to produce mulch for ongoing maintenance • Air Pollution • Install shade trees to reduce air pollution from heated parked cars. Trees have the ability to exchange O2 and CO2

17. PERFORMANCE OBJECTIVES • Education • Document parking lot retrofit project • Monitor success of implemented changes with respect to each performance objective • Provide training brochures with information on BMPs utilized on project site

18. Site Drain System Schematic Features: • 2 cisterns to collect runoff from rooftops and parking areas • Site infiltrates 3/4-inch storm • Cisterns hold average annual runoff • Small storms and first-flush storms infiltrated via porous paving and bio-swale Site divided into separate watersheds. Roof drainage stored and re-used.

19. BMPs for West Parking Area Features: • Install “speed bumps” to direct water to tree planters/infiltration trench • Plant new trees in infiltration zone • Install Infiltration Trench • Install 2 Cisterns to collect runoff; re-use for irrigation • Remove existing trees, gaining 45 parking spaces, and widen infiltration zone Detail of new parking strategy for West Parking Area.

20. West Parking Area Cistern (detail) Schematic sketch of stormwater collection, re-use, and monitoring system.

21. West Parking Area Stormwater Runoff Volumes 3/4” Storm = 12,250 ft3 Infiltration capacity of infiltration trenches = 15,000 ft3/day Irrigation needs of trees = 50,000 ft3/yr 10-yr storm = 155,000 ft3 Size of cistern required to meet 75% irrigation needs = 2,800 ft3

22. BMPs for East Parking Area Features: • Collect runoff by gravity from roofs of HQ • Hold roof runoff in cistern at SW corner of parking garage • Install irrigation system supplied by cistern; supplement during dry season • Install several varieties of porous pavement in parking area to allow infiltration from 3/4 inch storm Detail plan for parking lot section shows bays organized for additional trees and bioswale.

23. BMPs for East Parking Area Porous Pavement System A Porous Pavement System B Porous Pavement System C

24. Recommendations for follow-up Implementation Maintain the momentum created in these first 2 days. Here’s how: • Formalize the charrette design team into an ongoing committee to continue supporting design completion and implementation • Include Public Education staff on the team so they can continue and expand the outreach and share results with partner cities, agencies and stakeholders • Use the charrette products and process to explore inter-agency cooperation and collaboration • Enroll suppliers of BMPs to contribute products to the demonstrations • Create the facility to run more charrettes as a vehicle for promoting watershed management