LID facilities have been demonstrated to function well throughout frozen periods of the year even when all components were fully frozen for some part of the year. However, where the consequences of even temporary ponding would be entirely unacceptable, [[underdrain]] perforated pipes should be located below the frost line to reduce the threat of ice clogging. Ontario provincial standard drawings of frost penetration depth is available as OPSD 3090.100 for Northern Ontario and OPSD 3090.101 for Southern Ontario. [[Weirs]] are generally less prone to clogging from ice than [[orifices]] under all flow conditions, proprietary low flow devices are also available which are designed to mitigate clogging from ice or other solid debris.
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LID facilities have been demonstrated to function well throughout frozen periods of the year even when all components were fully frozen for some part of the year. However, where the consequences of even temporary ponding would be entirely unacceptable, [[underdrain]] perforated pipes should be located below the frost line to reduce the threat of ice clogging. Ontario provincial standard drawings of frost penetration depth are available from [https://www.library.mto.gov.on.ca/SydneyPLUS/TechPubs/Portal/tp/opsViews.aspx Ontario Ministry of Transportation] as OPSD 3090.100 for Northern Ontario and OPSD 3090.101 for Southern Ontario. [[Weirs]] are generally less prone to clogging from ice than [[orifices]] under all flow conditions, proprietary low flow devices are also available which are designed to mitigate clogging from ice or other solid debris.