Changes

*'''Potholes''': For porous asphalt or pervious concrete, isolated potholes can be patched with standard patching mixes. Patching can continue until the structural integrity of the pavement has been compromised or stormwater can no longer drain to the aggregate base. Then the surface will need to be torn up and replaced.  

*'''Potholes''': For porous asphalt or pervious concrete, isolated potholes can be patched with standard patching mixes. Patching can continue until the structural integrity of the pavement has been compromised or stormwater can no longer drain to the aggregate base. Then the surface will need to be torn up and replaced.  

*'''Uneven Pavers''': An uneven paver surface can be repaired by pulling up the pavers, redistributing the bedding layer, and then placing the pavers back. New filler stone will need to be swept into the replaced pavers. Typically the pavers are packed very tightly, and breaking one or more pavers will be necessary to pull up a group of pavers. Keeping a set of replacement pavers after construction will be useful for making future repairs.

*'''Uneven Pavers''': An uneven paver surface can be repaired by pulling up the pavers, redistributing the bedding layer, and then placing the pavers back. New filler stone will need to be swept into the replaced pavers. Typically the pavers are packed very tightly, and breaking one or more pavers will be necessary to pull up a group of pavers. Keeping a set of replacement pavers after construction will be useful for making future repairs.

*'''Weeds''': Over time, weed growth may become a problem, particularly on surfaces with infrequent traffic. Weeds can be an aesthetic issue and may also reduce the infiltration through the pavement. Keeping the pavement surface free of organic material through regular sweeping and vacuuming can impede weeds from taking root. Pulling weeds when they are small will limit damage to the pavement and loss of filler material between pavers. Ontario has banned the use of cosmetic herbicides.  

*'''Weeds''': Over time, weed growth may become an aesthetic problem, particularly on surfaces with infrequent traffic. Keeping the pavement surface free of organic material through regular sweeping and vacuuming can impede weeds from taking root. Ontario has banned the use of cosmetic herbicides for weed control.  

*'''Vacuuming''': Annual vacuuming of permeable interlocking concrete pavers can increase the operational lifespan of these pavers. <ref> Jennifer Drake, Andrea Bradford, Tim Van Seters and Glenn MacMillan, 2016. Evaluation of Permeable Pavements in Cold Climates. accessed at https://sustainabletechnologies.ca/app/uploads/2013/02/KPP-Final-2012.pdf </ref>  

*'''Vacuuming''': Annual vacuuming of permeable interlocking concrete pavers can increase the operational lifespan of these pavers. <ref> Jennifer Drake, Andrea Bradford, Tim Van Seters and Glenn MacMillan, 2016. Evaluation of Permeable Pavements in Cold Climates. accessed at https://sustainabletechnologies.ca/app/uploads/2013/02/KPP-Final-2012.pdf </ref>  

*'''Winter Maintenance''': Sand should not be spread on permeable pavement as it can quickly lead to clogging. Deicers should only be used in moderation and only when needed because dissolved constituents are not removed by the pavement system. Pilot studies at the University of New Hampshire Stormwater Center have found that permeable pavement requires 75% less salt than conventional pavement over the course of a typical winter season. <ref>University of New Hampshire Stormwater Center (UNHSC). 2007. 2007 Annual Report. Durham, NH.</ref>

*'''Winter Maintenance''': Sand should not be spread on permeable pavement as it can quickly lead to clogging. Deicers should only be used in moderation and only when needed because dissolved constituents are not removed by the pavement system. Pilot studies at the University of New Hampshire Stormwater Center have found that permeable pavement requires 75% less salt than conventional pavement over the course of a typical winter season. <ref>University of New Hampshire Stormwater Center (UNHSC). 2007. 2007 Annual Report. Durham, NH.</ref>