Changes

=='''Introduction'''==

=='''Introduction'''==

Conventional flat roofs on industrial, commercial, and institutional buildings are designed to quickly remove rainwater from their surfaces. The passive control strategy of these conventional roof assemblies provides no opportunity for rainwater reuse and contributes to downstream erosion and the potential for flooding. Credit Valley Conservation’s Smart Blue Roof (SBR) flips this idea on its head and uses an active control strategy to capture rainwater for reuse. This emerging technology has the capacity to effectively manage runoff, capture rainwater for non-potable reuse, and conserve energy through evaporative cooling.

Conventional flat roofs on industrial, commercial, and institutional buildings are designed to quickly remove rainwater from their surfaces. The passive control strategy of these conventional roof assemblies provides no opportunity for rainwater reuse and contributes to downstream erosion and the potential for flooding. Credit Valley Conservation’s Smart Blue Roof (SBR) flips this idea on its head and uses an active control strategy to capture rainwater for reuse. This emerging technology has the capacity to effectively manage runoff, capture rainwater for non-potable reuse, and conserve energy through evaporative cooling. Here are some '''fun facts''' about the SBR:

*The SBR is large enough to capture the 100-year design storm (the largest storm predicted to occur in a 100-year time period) within its footprint.

*The SBR is large enough to capture the 100-year design storm (the largest storm predicted to occur in a 100-year time period) within its footprint.

=='''Station 1 – Roof Surface'''==

=='''Station 1 – Roof Surface'''==

*Water can be ponded at an average depth of 130 mm, which equates to a depth of 75 mm at the parapet (roof edge) and 250 mm at the roof drains (lowest point).

*Water can be ponded at an average depth of 130 mm, which equates to a depth of 75 mm at the parapet (roof edge) and 250 mm at the roof drains (lowest point).

*Water can be stored on the roof for up to six (6) days.

*Water can be stored on the roof for up to six (6) days.

*The roof assembly is equipped with an electric field vector mapping (EFVM) leak detection system that can locate leaks with “pin-point” accuracy.

*The roof assembly is equipped with an electric field vector mapping (EFVM®) leak detection system that can locate leaks with “pin-point” accuracy.

=='''Station 2 – Modulating Control Valves'''==

=='''Station 2 – Modulating Control Valves'''==

The key mechanisms for the SBR’s ability to hold water are the modulating control valves installed on the third floor. The SBR roof drains are configured with valves that stop drainage from occurring.

The key mechanisms for the SBR’s ability to hold water are the modulating control valves installed on the third floor. The SBR roof drains are configured with valves that stop drainage from occurring.

=='''Station 3 – Third-Floor Treatment System'''==

=='''Station 3 – Third-Floor Treatment System'''==

The City of Mississauga required that CVC install a separate CSA-compliant water recirculation system on the third floor (see Figure 2). This system draws rooftop rainwater through the recirculation line that is immediately upstream of the east modulating control valve. The following are the main treatment components found on the third floor:

The City of Mississauga required that CVC install a separate CSA-compliant water recirculation system on the third floor. This system draws rooftop rainwater through the recirculation line that is immediately upstream of the east modulating control valve. The following are the main treatment components found on the third floor:

*'''Micron Filters:''' Filtration is important for removing impurities, eliminating odours, and ensuring debris does not impede the efficacy of the ultra-violet treatment (UV) unit by blocking light.

*'''Micron Filters:''' Filtration is important for removing impurities, eliminating odours, and ensuring debris does not impede the efficacy of the ultra-violet treatment (UV) unit by blocking light.

*'''UV Lamp:''' Disinfects rainwater by sterilizing bacteria and viruses with UV radiation. Note that UV disinfection does not have any residual effect that can be harmful to humans or aquatic life.

*'''UV Lamp:''' Disinfects rainwater by sterilizing bacteria and viruses with UV radiation. Note that UV disinfection does not have any residual effect that can be harmful to humans or aquatic life.

*'''Chlorine Pump:''' Provides a chlorine residual of 0.5 mg/L that can ensure that rainwater on the roof surface is protected from recontamination.

*'''Chlorine Pump:''' Provides a chlorine residual of 0.5 mg/L that can ensure that rainwater on the roof surface is protected from recontamination.

 

=='''Station 4 – Basement Cistern and Treatment System'''==

=='''Station 4 – Basement Cistern and Treatment System'''==

When rainwater is drained from the roof surface into the basement, it is collected by a rainwater cistern (CVC’s old, passive system). Water from this cistern can be pumped through the SBR’s second CSA-compliant treatment system. The following are the main treatment components of this basement system:

When rainwater is drained from the roof surface into the basement, it is collected by a rainwater cistern (CVC’s old, passive system). Water from this cistern can be pumped through the SBR’s second CSA-compliant treatment system. The following are the main treatment components of this basement system:

*'''Settling Tanks:''' Allow any sediment that is suspended in the rainwater to settle.

*'''Settling Tanks:''' Allow any sediment that is suspended in the rainwater to settle.

*'''Rainwater Cistern:''' Holds water before it is pumped through the treatment system.

*'''Rainwater Cistern:''' Holds water before it is pumped through the treatment system.

*'''Micron Filter:''' Removing impurities, eliminating odours, and ensuring debris does not impeded the efficacy of the UV treatment unit by blocking light.

*'''Micron Filter:''' Removes impurities, eliminates odours, and ensures debris does not impeded the efficacy of the UV treatment unit by blocking light.

*'''UV Lamp:''' Disinfects rainwater by sterilizing bacteria and viruses with UV radiation. Note that UV disinfection does not have any residual effect that can be harmful to humans or aquatic life.

*'''UV Lamp:''' Disinfects rainwater by sterilizing bacteria and viruses with UV radiation. Note that UV disinfection does not have any residual effect that can be harmful to humans or aquatic life.

*'''Chlorine Pump:''' Provides a chlorine residual of 0.5 mg/L that can ensure that rainwater is protected from recontamination in the distribution line or when supplied to the toilets.

*'''Chlorine Pump:''' Provides a chlorine residual of 0.5 mg/L that can ensure that rainwater is protected from recontamination in the distribution line or when supplied to the toilets.

*'''Cistern Level Sensor:''' Measures elevation of rainwater in the cistern. This is useful for determining if the cistern needs to be replenished.

*'''Cistern Level Sensor:''' Measures elevation of rainwater in the cistern. This is useful for determining if the cistern needs to be replenished.

*'''Rooftop temperature Sensors:''' Measures the temperatures above the building and on the inside of the roof assembly (below the concrete roof slab). These sensors compare the heat gradient across the roof assembly where the SBR is located and where a conventional roof system remains. By doing so, the cooling benefit and energy savings of the SBR can be calculated.

*'''Rooftop temperature Sensors:''' Measures the temperatures above the building and on the inside of the roof assembly (below the concrete roof slab). These sensors compare the heat gradient across the roof assembly where the SBR is located and where a conventional roof system remains. By doing so, the cooling benefit and energy savings of the SBR can be calculated.