OutlineGo over why we need to reduce stormwater runoffIntroduction to green roofs as green infrastructureOnCenter green roof and our plans for research there
Combined Sewer System (CSS): the same sewer system is used for both stormwater and domestic wastewaterCombined Sewer System (CSO): overflow of combined sewage and stormwaterCSOs can be reduced by “gray infrastructure”holding tanks, regional treatment facilities, enlarged central treatment plantsGray infrastructure is brute force approachconcrete, chemicals, & high energy use: treating large volumes of raw sewage diluted with stormwaterGreen infrastructure (GI) technologies used for stormwater management are designed to protect or restore the natural hydrology of a siteRepresent an interface between human and natural systems
Onondaga County has integrated numerous green technologies into previously unpopular stormwater management plans in only the past few years. The speed at which these technologies were both accepted and adopted can be understood as an alignment of several positive factors. Historical interest in preservation of quality of Onondaga LakeShift in mindset of officials (local/and national) as to what technologies are effective and practical optionsSupport of all regulating parties Key advocates (ie, “champions”) pushing for sustainable technology (community members and govt officials); dissent from public towards current management plans and support for alternative plans by grassroots organizationsEconomic opportunities (grants, incentives, cost/benefit) Onondaga County had good credit and allowed funding to be secured outside of EFCReasonably small metropolitan area which enables good ideas to be implemented more quickly than in large citiesIn April 2011, the EPA named Syracuse as one of 10 partner communities in their new strategic green infrastructure agenda, which outlines the activities that the EPA will undertake to help communities implement green infrastructure approaches. This will allow for other communities to learn from Onondaga County on how to best use green infrastructure as a part of their stormwater management plans.
Stormwater management, reduced urban heat island, extended roof life, increased worker productivitylaw since 1989 creating the common green roofExtensive vs. IntensivePlants: Sedum, Sempervivum (give intensive examples)Benefits: Economic, aesthetic, environmentalPrivate vs. publicExtensive less than 6 inchesIntensive greater than 6 inchesEnvironmental Reduction in urban heat island, GHG, smog events, pollutionStormwater retention/delayEconomicEnergy cost savingsAestheticHard to quantify but improved worker productivity, public space
Shallow substrate- less than 6 inchesSmall limited plants: including sedum, sempervivumdon’t accumulate biomass, which just adds more weight, requires minimal maintenanceintensive in contrastdeeper substrate, greater than 6 inches, and up to a foot or more, supports greater variety of plant types-small trees, bushes, flowers, more garden or yard like requires much more maintenance to remove biomass, to irrigaterequires significantly more structural support for increased weight load
currently being constructed above us, the oncenter roof is…satellite photo from may, can see membrane construction
extensive green roof, no public accessplanted primarily with sedum, type of succulent, very hardy plants
Temperature sensors:4 sensors at each of 5 locations outside3 sensors at 3 locations inside convention center main hall CS109BetaTherm 10K3A1 Thermistor6 5 soil moisture sensors CS616
Weighing bucket to capture precipitationIn-line flow sensors which will capture 20 of 25 drains (flow off 80% of the roof) capture flow from first 8evapotranspiration terms??
Probability density function of rainfall events in SyracuseThis graph is for 2010 but the shape, skew to the left is common to at least the past decade. Significant portion of the rainfall falls in very small events which makes them a challenge to measure in the drains.
25 roof drains5 temperature sensorsmark temperature sensor locations, shows cable runs
20 campbell scientific temperature sensors distributed through the roof (thermistors enclosed in a durable casing)3 inside against the ceiling of the main convention center hall
Temperature sensors located in layers throughout the roof at 5 locations. These locations were spaced across the unfinished portion of the roof during install. This permitted the installation of the sensors within the layers of the roof, creating 5 vertical temperature profiles.
Use of gi to reduce stormwater runoff squier - sept 2011
Use of Green Infrastructure to Reduce Stormwater RunoffMallory Squier, Pavle Bujanovic, Carli Flynn, and Cliff Davidson Syracuse University and Syracuse Center of Excellence Syracuse COE Symposium 22 September 2011
Background• Combined Sewer System (CSS): the same sewer system is used for both stormwater and domestic wastewater• Combined Sewer Overflow (CSO): overflow of combined sewage and stormwater• CSOs can be reduced by “gray infrastructure” • holding tanks, regional treatment facilities, enlarged central treatment plants• Gray infrastructure is brute force approach• Green infrastructure (GI) technologies used for stormwater management are designed to protect or restore the natural hydrology of a site
Onondaga Lake • Large proportion of the source water for Onondaga Lake (up to 20%) comes directly from METRO outflows • CSOs are a major contributor of bacteria, floating trash, organic material, solids and grit to the lake and its tributaries. Onondaga County • 8 CSO sewersheds • Precipitation “trigger” events as small as 0.10-0.15 in/hrOnondaga Lake , Onondaga Lake Partnership. CSO point , CNY Regional Planning & Development Board.
GI in Onondaga CountyFactors allowing for rapid adoption of green infrastructuretechnologies:• Shift in local and national mindset• Support of all regulating parties• Support of community advocates• Economic opportunities• Reasonably small metropolitan areaApril 2011 Syracuse was named one of 10 partnercommunities by the EPA in their new strategic greeninfrastructure agenda.
The green roof• Vegetated roof• Benefits: – environmental – economic – aesthetic
Green roof: typical structureComparison of Typical Conventional vs. Green Roof Construction. Liu, 2003.
Green roof: types• Extensive – Shallow substrate – Low maintenance – Limited plant variety• Intensive – Deep substrate – Heavier weight load Extensive green roof. City of Windsor, 2009.
OnCenter green roof • 60,000 square feet • Designed to retain 1 million gallons stormwater annuallyGoogle Earth. September 2011.