Changes

==Performance==

==Performance==

<h3>Water Quantity</h3>

<h3>Water Quantity</h3>

In theory a large enough RWH cistern could retain 100% of a single storm. However, sizing a stormwater cistern must account for regulatory requirements, available space, budget, and draw-down i.e. rate of use. If a RWH system is being employed for storm water control, the cistern size will typically be greater than that for optimized potable water use reduction.

In theory a large enough RWH cistern could retain 100% of a single storm. However, sizing a stormwater cistern must account for regulatory requirements, available space, budget, and draw-down i.e. rate of use. If a RWH system is being employed for storm water control, the cistern size will typically be greater than that for optimized potable water use reduction.<br>

In 2007-2010 STEP monitored and modelled three rainwater harvesting systems in the Greater Toronto Area[http://www.sustainabletechnologies.ca/wp/home/urban-runoff-green-infrastructure/low-impact-development/rainwater-harvesting/performance-evaluation-of-rainwater-harvesting-systems-toronto-ontario/]. Each system was sized  to balance stormwater management objectives with with potable water use reduction for irrigation and toilet flushing. Key findings include:

In 2007-2010 STEP monitored and modelled three rainwater harvesting systems in the Greater Toronto Area[http://www.sustainabletechnologies.ca/wp/home/urban-runoff-green-infrastructure/low-impact-development/rainwater-harvesting/performance-evaluation-of-rainwater-harvesting-systems-toronto-ontario/]. Each system was sized  to balance stormwater management objectives with with potable water use reduction for irrigation and toilet flushing. Around 18-20% of the precipitation was lost directly from the rooftop, and the annual stormwater capture varied between 18 and 42 %.

*Around 18-20% of the precipitation was lost directly from the rooftop,

*Annual stormwater capture varied between 18 and 42 %.

<h3>Water Quality</h3>

<h3>Water Quality</h3>

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