Changes

<p>The important water quality parameters for harvested rainwater differ from other types of LID. This is due to the potential for direct human contact, rather than environmental discharge. As of July 2017, the CSA and ICC are finalizing a standard[https://www.iccsafe.org/wp-content/uploads/110116-Draft-CSA_ICC-B805-Rainwater-Harvesting.pdf] which specifies different water quality treatments according to the source (roof runoff versus stormwater runoff) and the intended use. </p>

The important water quality parameters for harvested rainwater differ from other types of LID. This is due to the potential for direct human contact, rather than environmental discharge. As of July 2017, the CSA and ICC are finalizing a standard[https://www.iccsafe.org/wp-content/uploads/110116-Draft-CSA_ICC-B805-Rainwater-Harvesting.pdf] which specifies different water quality treatments according to the source (roof runoff versus stormwater runoff) and the intended use.

<p> Tier 1 end uses are most readily achievable, requiring only that larger particles are filtered out of the water. Removing the bulk of the solid particles reduces the [[Water Quality#Nutrients|nutrient]] concentration in the water and prevents clogging of the water distribution system. Toilet and urinal flushing are the next most popular use of harvested rainwater. If flushing or other higher tier end uses are desired, disinfection of some type is required and consideration may be given to colour and odour of the water. Technologies for achieving higher standards of water quality include:

<p> Tier 1 end uses are most readily achievable, requiring only that larger particles are filtered out of the water. Removing the bulk of the solid particles reduces the [[Water Quality#Nutrients|nutrient]] concentration in the water and prevents clogging of the water distribution system. Toilet and urinal flushing are the next most popular use of harvested rainwater. If flushing or other higher tier end uses are desired, disinfection of some type is required and consideration may be given to colour and odour of the water. Technologies for achieving higher standards of water quality include:

*<strong>Ultraviolet (UV) disinfection</strong> requires additional filtration to remove particles so that the light can penetrate the water and destroy the viruses and bacteria,  

<li><strong>Ultraviolet (UV) disinfection</strong> requires additional filtration to remove particles so that the light can penetrate the water and destroy the viruses and bacteria, </li>

*<strong>Chlorine disinfection</strong> also requires additional filtration to remove larger particles,   

<li><strong>Chlorine disinfection</strong> also requires additional filtration to remove larger particles,  </li>

*<strong>Micro- or Ultra- filtration</strong> uses such fine membranes that the vast majority of harmful viruses, bacteria etc. are excluded from the water directly.  

<li><strong>Micro- or Ultra- filtration</strong> uses such fine membranes that the vast majority of harmful viruses, bacteria etc. are excluded from the water directly. </li>

All three water purification technologies require specialist design and consultation with a subject matter expert is recommended for higher tiers of water use.

 

All three water purification technologies require specialist design and consultation with a subject matter expert is recommended for higher tiers of water use. </p>

|+ Water quality treatment required for multi-residential and commercial applications (Abridged from [https://www.iccsafe.org/wp-content/uploads/110116-Draft-CSA_ICC-B805-Rainwater-Harvesting.pdf CSA B805 draft])

<tr class="success" >

<tr class="success" >

     <th colspan=2 style="text-align: center;">Application</th>

     <th colspan=2 style="text-align: center;"></th>

     <th colspan=3 style="text-align: center;">Roof runoff pathogen reduction</th>

     <th colspan=3 style="text-align: center;"></th>

     <th colspan=3 style="text-align: center;">Stormwater pathogen reduction</th>

     <th colspan=3 style="text-align: center;"></th>

       </tr>

       </tr>

       <tr><td>End Use Tier</td><td>Example uses</td><td>Viruses</td><td>Bacteria</td><td>Protazoa</td><td>Viruses</td><td>Bacteria</td><td>Protazoa</td></tr>   

       <tr><td>End Use Tier</td><td>Example uses</td><td>Viruses</td><td>Bacteria</td><td>Protazoa</td><td>Viruses</td><td>Bacteria</td><td>Protazoa</td></tr>