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Line 52: − + + + + + + + + + − <h5>Source Water Quality </h5>+ − <p> A study of many types of roof surfaces in Texas found: − <ul> − <li>'Cool' membrane, concrete tile, and metal roofs all produced water of similar good quality for non-potable use, </li> − <li>The runoff water from asphalt shingle and green roofs contained significantly more dissolved organic carbon (DOC). The DOC can add a yellow colour to the water. If the water is treated with chlorine, for drinking purposes, DOC can produce toxic compounds[http://www.sciencedirect.com/science/article/pii/S0043135410008535]. </li> − </ul></p> − <p> Research in Hamilton, ON assessed the water quality of rain collected from three highly reflective 'cool roof' membranes[http://wst.iwaponline.com/content/70/7/1205?utm_source=TrendMD&utm_medium=cpc&utm_campaign=Water_Science_and_Technology_TrendMD_0]. Key findings: − <ul><li>The water was free from significant contamination with by-products of plastic manufacture and did not show elevated levels of the five metals tested. </li> − <li>Increased microbiological contamination was found in runoff from roof areas where ponding occurred.</li> − </ul> − </p> − <p>Increased microbiological contamination in roof runoff is also associated with warmer weather[http://www.sciencedirect.com/science/article/pii/S0043135411002181].</p>
no edit summary
*<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.
*<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.
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.
{|class="wikitable"
{|class="wikitable"
|+ 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])
|+ 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])
*Misting stations
*Misting stations
*Swamp coolers}}
*Swamp coolers}}
|0||99.999%||99.999%||colspan = "3" style="text-align: center; background: orange;"|Outside of the scope of the CSA standard
|0||99.999%||99.999%||colspan = "3" style="text-align: center;"|Outside of the scope of the CSA standard
|}
|}
===Source Water Quality===
A study of many types of roof surfaces in Texas found:
*'Cool' membrane, concrete tile, and metal roofs all produced water of similar good quality for non-potable use,
*The runoff water from asphalt shingle and green roofs contained significantly more dissolved organic carbon (DOC). The DOC can add a yellow colour to the water. If the water is treated with chlorine, for drinking purposes, DOC can produce toxic compounds<ref>Mendez CB, Klenzendorf JB, Afshar BR, et al. The effect of roofing material on the quality of harvested rainwater. Water Res. 2011;45(5):2049-2059. doi:10.1016/j.watres.2010.12.015.</ref>.
Research in Hamilton, ON assessed the water quality of rain collected from three highly reflective 'cool roof' membranes<ref>Cupido, A., B. Baetz, Y. Guo, and A. Robertson. 2012. An evaluation of rainwater runoff quality from selected white roof membranes. doi: 10.2166/wqrjc.2012.011.</ref>. Key findings:
*The water was free from significant contamination with by-products of plastic manufacture and did not show elevated levels of the five metals tested.
*Increased microbiological contamination was found in runoff from roof areas where ponding occurred.
Note: Increased microbiological contamination in roof runoff is also associated with warmer weather <ref>Vialle C, Sablayrolles C, Lovera M, Jacob S, Huau MC, Montrejaud-Vignoles M. Monitoring of water quality from roof runoff: Interpretation using multivariate analysis. Water Res. 2011;45(12):3765-3775. doi:10.1016/j.watres.2011.04.029.</ref>.
==References==