Changes

[[File:Screenshot 2025-09-24 121338.png|400px|thumb|right|From left to right: Drainage swale and fitness path, biofilter stone trench, permeable surfaces in outdoor eating areas, rainwater cistern, native plantings, and vegetated biofilter (STEP, 2015) <ref name=HONDA></ref>.]]

[[File:Screenshot 2025-09-24 121338.png|400px|thumb|right|From left to right: Drainage swale and fitness path, biofilter stone trench, permeable surfaces in outdoor eating areas, rainwater cistern, native plantings, and vegetated biofilter (STEP, 2015) <ref name=HONDA></ref>.]]

The headquarters of Honda Canada is located at 180 Honda Boulevard in Markham, Ontario.  The 17.9 ha catchment is divided up into three subcatchments with separate outlets: west (6.3 ha, 53% impervious), Northeast (5.4 ha, 55% impervious), Southeast (6.4 ha, 83% impervious).  Overall site imperviousness is 64%.  LID practices replaced the need for a stormwater pond, allowing the facility to maintain a large sports field in the northeast portion of the site.  

The headquarters of Honda Canada is located at 180 Honda Boulevard in Markham, Ontario.  The 17.9 ha catchment is divided up into three subcatchments with separate outlets: west (6.3 ha, 53% impervious), Northeast (5.4 ha, 55% impervious), Southeast (6.4 ha, 83% impervious).  Overall site imperviousness is 64%.  LID practices replaced the need for a [[wet ponds|stormwater pond]], allowing the facility to maintain a large sports field in the northeast portion of the site.  

'''Stormwater Management Criteria'''

'''Stormwater Management Criteria'''

#The primary practices to achieve on-site runoff retention and peak flow attenuation include a series of large gravel trenches with underdrains (mostly in the SE catchment), a 636 m3 cistern draining water from a 2.4 hectare roof, a small dry pond, permeable pavers and surface swales.  

#The primary practices to achieve on-site runoff retention and peak flow attenuation include a series of large gravel trenches with underdrains (mostly in the SE catchment), a 636 m3 cistern draining water from a 2.4 hectare roof, a small dry pond, permeable pavers and surface swales.  

#Underdrain in the trenches is raised 0.15 m off the native soil to provide quality and water balance control through infiltration.  Trees and vegetation on top of the gravel filled trenches help reduce runoff through evapotranspiration.  

#Underdrain in the trenches is raised 0.15 m off the native soil to provide quality and water balance control through infiltration.  Trees and vegetation on top of the gravel filled trenches help reduce runoff through evapotranspiration.  

#Underdrain is undersized to increase detention times during flood events.  Orifice controls are installed in the downstream sewer to control release rates.  

#Underdrain is undersized to increase detention times during flood events.  [[Orifice]] controls are installed in the downstream sewer to control release rates.  

#An automated irrigation system for the playing field and vegetated areas draws stored water from the rainwater cistern to increase capacity during storm events.  Outside of the growing season, rainwater from the cistern drains directly to a dry pond which provides temporary storage and release.

#An automated irrigation system for the playing field and vegetated areas draws stored water from the rainwater cistern to increase capacity during storm events.  Outside of the growing season, rainwater from the cistern drains directly to a [[dry pond]] which provides temporary storage and release.

'''Monitoring and Modelling Results'''

'''Monitoring and Modelling Results'''

STEP/TRCA conducted a hydrologic monitoring and modelling study of the site in 2012/13 with researchers from The Metropolitan University to assess runoff volume and peak flow reductions.  Results showed that, relative to a conventional stormwater approach without LID, runoff was reduced over the study period by between 30% and 35% for the entire site, and by between 58 and 62% in the catchment with a higher density of LID practices.  Peak flows were also reduced by 73 to 78%.  In the Northeast catchment, 20% of rainfall harvested from the roof was stored and reused for irrigation during the summer months.  This reuse volume represented 6% of total site rainfall over 8 months.  A hydrologic model calibrated using monitored data showed that the stormwater management system met the design objective of providing quantity control for the post development 100 year storm.

STEP/TRCA conducted a hydrologic monitoring and modelling study of the site in 2012/13 with researchers from The Metropolitan University to assess runoff volume and peak flow reductions.  Results showed that, relative to a conventional stormwater approach without LID, runoff was reduced over the study period by between 30% and 35% for the entire site, and by between 58 and 62% in the catchment with a higher density of LID practices.  Peak flows were also reduced by 73 to 78%.  In the Northeast catchment, 20% of [[Rainwater Harvesting|rainfall harvested]] from the roof was stored and reused for irrigation during the summer months.  This reuse volume represented 6% of total site rainfall over 8 months.  A hydrologic model calibrated using monitored data showed that the stormwater management system met the design objective of providing quantity control for the post development 100 year storm.

 

===Example 2: [https://sustainabletechnologies.ca/app/uploads/2020/06/Wychwood-Report.pdf Wychwood Subdivision in Brampton]===

===Example 2: [https://sustainabletechnologies.ca/app/uploads/2020/06/Wychwood-Report.pdf Wychwood Subdivision in Brampton]===