Los delitos contra la libertad Tema n.°
4. Delito de violación del secreto de las comunicaciones
The first analysis technique identified urban-related challenge as the economic pathway to introducing the biophilic element, green roofs, in Toronto. Stormwater runoff and urban heat island effect were thus identified as externalities that required the City’s attention. The rising costs of stormwater management and rising temperature prompted exploration into cost- effective solutions for the city. Understanding the challenges of urban environments, particularly stormwater runoff, and the success experienced in Chicago and New York,456 the city of Toronto wanted to tackle these problems with the use of green roofs. Toronto, like many North American cities, has a combined pipe for stormwater runoff and sanitary sewer. During dry weather, this combined sewer system works by carrying both stormwater and sanitary sewage to treatment plants. During wet weather, however, the increased volume of stormwater exceeds the treatment plant’s capacity releasing untreated sewage into rivers
and lakes. This combined sewer overflow (CSO) problem has been identified as a significant issue that required immediate attention.457 No economic costing of CSO issue has been found, but the cost of infrastructure is widely understood. The city of Toronto estimated that to cover the cost of storm water management, a storm water utility of over a billion Canadian dollars in capital expenses and CAD$233 million in operating expenses would be required for 25 years.458 Alternative options were preferred due to the steep cost of storm water infrastructure.
4.7.1 Economic push factors
As stormwater runoff and urban heat island effect were clearly identified as pressing issues in Toronto, identifying relevant services to address this issue was necessary. The data collected along with the interviews conducted confirmed that the ecosystem services, stormwater management and climate mitigation, provided the compelling elements for the business case in Toronto.
Valuation method in Toronto entailed emphasising the benefits that could be quantified, which were of interest to the City of Toronto. Though interviews highlighted that the quantification of the economic benefits related to green roofs was difficult due to a range of factors including the fact that there are significant costs not being paid by building owners, including the contribution of that building to urban air pollution, climate change, or the urban heat island effect.459 However, until building owners receive financial benefit for reducing the building’s contribution to these problems, or are required to pay for these problems commensurate to the building’s individual impact (as opposed to paying a flat rate), these remain as externalities and are unlikely to factor into a decision making process. Interviews further emphasised that if there was a viable short term business case for buildings to install green roofs without incentives, then they would already be doing so (i.e. market forces would prevail).460 Despite this, the report by Ryerson University found the following cost savings as a result of the following ecosystem services (Table 4-5): 461
Table 4-5: Toronto identified benefits
Category Category of Benefit Initial cost saving
(Canadian Dollars)
Annual cost saving (Canadian Dollars)
Stormwater
Alternate best management
practice cost avoidance $79,000,000 -
Pollutant control cost
avoidance $14,000,000 -
Erosion control cost
avoidance $25,000,000 -
Combined Sewer Overflow (CSO)
Storage cost avoidance $46,600,000 -
Reduced beach closures - $750,000
Urban Hear Island (UHI)
Savings in annual energy
use - $12,000,000
Cost avoidance due to peak
demand reduction $79,800,000 -
Source: Banting et al (2005)
4.7.2 Economic pull factors
Interviews cautioned against focusing on one potential benefit such as how green roofs can assist in mitigating the impact of stormwater runoff, as there are mechanical devices that could provide a similar service and potentially at a lower cost.462 Hence, no other solution would achieve the whole suite of benefits offered by a green roof (i.e. social, economic and environmental benefits). The benefits include capturing and storing rainfall, reducing building energy demand, and reducing the urban heat island effect (through reduced building material temperatures and the localised cooling effects of evapotranspiration) made this biophilic element a more viable option.463 464 465 Hence the pull factors played a compelling role in Toronto.
Finding the other benefits justified the widespread implementation of green roofs. Interviews explained that the benefits did not necessarily add up individually, however when they calculated the available rooftop area feasible for green roofs it highlighted the massive area in the city of Toronto.466 This made it clear that revitalising urban “dead space” in Toronto collectively had significant benefits for the city. In addition to recognising the impact of aggregated benefits, the commissioned study also highlighted a range of benefits identified from the literature review.467 These were presented as part of the study to provide further support for the business case. Some of the services identified were: energy budgets of individual buildings; the urban heat island; stormwater management strategies; urban air quality; waste management from increase in roof material life cycle; urban agriculture, noise reduction, real estate, therapeutics, open space; urban amenities, such as food production, aesthetics, recreation; promoting horticulture/landscaping, promoting of biodiversity and wild life protection; and promoting of health and well-being. Reference to these international
studies showcased the wider benefits of green roofs. Interviews highlighted that at the time local studies of green roof performance was scarce, with only reference to three local studies that highlighted the UHI, stormwater management and air quality improvement benefits.468
4.7.3 Economic valuation method
With
rising urban-related challenges, the research team at Ryerson University were commissioned to explore the costs and benefits of city-wide green roofs in Toronto. Hence urban heat island and stormwater management issues were the first economic push factors that led to this exploration. The report attempted to quantify the potential cost savings by measuring the following metrics: energy savings, cost avoidance due to reduced peak demand, alternate BMP, pollutant control, erosion control, storage and reduced beach closures. For this reason, these metrics are categorised as monetary benefits (MB). The primary focus is evidently cost savings i.e. exchange value theory. This demonstrates the important role monetary valuation played in Toronto.Although the report was commissioned to explore the costs and benefits of green roofs in Toronto, not all benefits were locally quantified and rather some benefits were identified and referred to by exploring relevant studies. Table 4-6 describes the pull factor metrics that were locally quantified and the other benefits that were identified from the literature. The benefits that were quantified, the report referred to local studies, using evidence from those studies and attempted to quantify how widespread implementation of green roofs could potentially affect Toronto. When local studies were not available, the report referenced international studies that resemble Toronto. The 2005 Economic Impact study also quantified the potential savings as a result of enhancing urban air quality, saving energy and reducing carbon dioxide. For this reason, their respective metrics have been categorised as measurable benefits.
Table 4-6: Toronto Economic Push and Pull Factors
Push
factor(s) Push factor(s) metrics Pull Factor(s) Pull factor(s) metrics UHI Energy savings
MB
Cost avoidance due to peak MB demand reductions
Energy savings Annual energy use savings MB
Health and well- being
Cost avoidance due to peak demand reductions MB
Savings from CO2 reductions MB
Urban amenities Literature review -
Urban air quality Local study impacts on CO, NO2, O3, PM10, SO2 MB
Storm water runoff
Alternate BMP cost avoidance MB Pollutant control cost avoidance MB Erosion control cost avoidance MB Storage cost avoidance MB Reduced beach closures MB
Waste
management from increase in roof material “life cycle”
Literature review - Urban agriculture Noise reduction Real estate Therapeutics Increase open space Promoting horticulture/landsc aping Promoting of biodiversity and wild life protection
GHG reduction Savings from CO2 reductions MB