Cities Alive 12th Annual Green Roof & Wall Conference Rethinking Green Infrastructure Brad Bass Great Lakes Issues & Management Reporting Section Environment Canada PresencePresence ofof algalalgal bloomsblooms andand hypoxichypoxic eventsevents havehave renewedrenewed interestinterest inin quantifyingquantifying phosphorousphosphorous loadsloads andand dynamicsdynamics inin thethe LakeLake ErieErie basinbasin Actual LID Installed Comparison of Green Infrastructure Usage Established Urban forests Interest in Sustainable municipal Permeable Rai n Downspout / wetlands / learning more Infiltration Tree City Green roof Rain gardens Bi oswales street Bioretention programs and pavement barrels disconnection natural space about green planters cover design funding protection infrastructure Canada Toronto London St. Catherines Niagara Falls Hamilton Owen Sound Kingston Guel ph Windsor Waterloo Uni ted States Portland, Oregon Chicago, Illinois New York City, New York Observations of Green Infrastructure Percentage Removal Efficiency of Phosphorus, Apex NC International Stormwater Best Management Practices (BMP) Database Pollutant Category Summary: Nutrients. International Stormwater BMP Database, www.bmpdatabase.org. Observations of Green Infrastructure McElmurray, S.P., Confessor, R., and Richards, R.P. (2013). Reducing Phosphorus Loads to Lake Erie: Best Management Practices Literature Review. Prepared for the International Joint Commission. Total P removal Total P removal was observed in was observed in <15% of 55% of detention bioswale - storm basin – storm events events International Stormwater Best Management Practices (BMP) Database Pollutant Category Summary: Nutrients. International Stormwater BMP Database, www.bmpdatabase.org. Improving Green Infrastructure • Modify Growing Media • Maintenance • Add filters • Modify Structure Growing Media • Zebra Mussel Shells • Reduce impact of P- load • Modify pH • 6.5 ideal for P-uptake • > 8 water P not available – Roots release acid to lower pH – Washed away by water Growing Media - Biology Zebra Mussels as Growing Medium Mat: 30-55% mussel shells mixed with coir fiber, yard waste compost, and peat moss. Tray: 5-65% mussel shells mixed with composted pine bark, peat moss, turface, and/or biochar Growing Media – water holding capacity • Biochar – Water holding capacity – Nutrient storage & supply • Organics vs. Inorganics – Higher organic media might increase water holding capacity Growing Media Mineral Example • Aluminum • Developed as fertilizer • Added to bog filter – Penn State University • Iron • Red sand – Richmond Hill • Slag Existing Rating Systems • LEED (Leadership in Energy and Environmental Design) • Sustainable Sites Initiative • Living Building Challenge • Certified Wildlife Habitat • Roofpoint • Green Globes • Envision • BREEAM (Building Research Establishment Environmental Assessment Method) Credits in Sustainable Sites V.2 Description of Credit Points Relevance Manage precipitation on site Required All green roofs and –60th percentile event other technologies. Green Walls are a ? Manage precipitation on site 4-5 points All green roofs and –85th-90th percentile event out of 200 other technologies. Green Walls are a ? Stormwater feature as 4-5 points Intensive green roofs amenity – must use out of 200 and other precipitation only for water technologies. Green input and must accessible Walls are a ? Courtesy of Green Infrastructure Foundation Living Architecture Performance Tool • Creating a comprehensive series of metrics to evaluate the performance of green roof and wall technologies • Completed draft white papers in 2014 on biodiversity and water related performance metrics • Will revolutionize green roof and wall industry Drexel University Philadelphia, PA Award of Excellence 2013 Metrics for Stormwater Volume – Living Architecture Performance Tool Intent Metric Research Basis Maximize Increased Runoff reductions not based evapo- evapotranspiration on infiltration but based on transpiration by increasing evapotranspiration by increasing hydraulic (especially on green roofs). the flow time resistance, density Maximize time that water and productivity of in contact with substrate vegetation and plant roots. Control transmissivity of layers, length & passage of flow path Courtesy of Green Infrastructure Foundation Structural Modification • Imagine a bioswale of infinite length • Design for – Rate of flow – Hydraulic retention Recognizing and Measuring Capillary Index Optigreen 900 g/m2 capillary fleece | Capillary index: 39.9 cm ( ~16 inches ) slope = 4x dry weight slope Courtesy of Charlie Miller DRAFT – Page 18 – December 5, 2014 Absement • Mann and Janzen coined the term ‘Absement’ for the time integral of displacement and hypothesized that it may explain the acoustics of certain water-based instruments A Thought Experiment Absement – Height/Length and Time Absement of 20 metre-hours HEIGHT/LENGTH TIME 20 metres • 1 hour 10 metres • 2 hours 5 metres • 4 hours 4 metres • 5 hours 2 metres •10 hours 1 metres •20 hours Green Infrastructure: Control Water Height or Velocity • Space-time geometry of growing media (complex) • Baffles to mimic increasing length • Macro Design Baffles: Green Walls Macro Design: Bioswale Creating Change NYC City Planning /Civic Design Macro Design: Green Wall An Adaptive Paradigm: Coupling water & waste flows with ecological development to enhance environmental quality Water and nutrient flow Runoff as Resource Jamaica Bay Atlantic Ocean • A million trees in enhanced tree pits can evaporate about 40 million gallons of water per day, fixing ≈ 2,000 tons of carbon in the proclss NYCHA Green Façade Proposal • NYC has more than 300 square miles of vertical walls • Running greywater or stormwater through containers would allow very large quantities of water to be treated by roots and microbes at low cost, while increasing habitat area, biodiversity, and cooling the City Some new opportunities Multi-layer Biofilters Integrated Green Walls-Biofilters-Landscape Multi-feature Stormwater Filtering Acknowledgements Acknowledgements: •Steve Mann Department of Mechanical & Industrial Engineering University of Toronto •Ryan Janzen Department of Mechanical & Industrial Engineering University of Toronto •Maya Burhanpurkar President, Science Expo •Paul Mankiwicz The Gaia Institute •Bob Cameron Penn State University •Shawn McElmurry Wayne State University.