Stormwater Quality Design Manual (May 2007) - City of Sacramento ...

Technical RequirementsGreen RoofTable GR-2. Inspection and Maintenance Recommendations for Green Roofs 1ActivityScheduleIrrigation• Irrigation can be accomplished by hand watering or automaticsprinkler systems (preferable). Follow the short and long-termwatering regimes designed by the landscape designer, based on theselected plants and their water needs.Vegetation• Inspect and maintain vegetation to ensure at least 90% vegetativecover (visual guideline) at the end of the plant establishment periodand thereafter. Replace dead plants as needed. Use fertilizerssparingly, if at all.• Remove fallen leaves and debris from deciduous plant foliage.Repair/replace damaged or dead vegetation to maintain requiredcover.• Employ integrated pest management (IPM) practices to minimize oreliminate use of chemical pesticides and herbicides. Remove weedsmanually whenever possible.• During drought conditions, apply mulch or shade cloth as needed toprevent excess solar damage and water loss.• Mow grasses and remove clippings.Irrigate plants regularly until they areestablished and thereafter as neededInspect monthly during vegetationestablishment period; thereafter,annually or as needed.As neededAs needed. Remove weeds duringgrowing season.As neededAs neededComponent Layers• Inspect/maintain waterproof membrane for proper operation,waterproofing integrity, and structural stability.• Inspect/maintain drainage layer flow paths for proper operation.Determine if drain pipes and inlets are in good condition and checkdrain inlets for obstructions. Clear inlet pipe of growth media,vegetation, debris or other materials. Identify and correct sources ofobstructions.• Inspect growth medium for evidence of erosion from wind or water. Iferosion channels are evident, stabilize with additional growth mediumand plants.2-3 times per yearAt least twice per year during wetseason, preferably during and afterstorms. Additional inspections afterperiods of heavy runoff are desirable.2-3 times per year. Additionalinspections after periods of heavy runoffare desirable.Other• Use spill prevention measures for rooftop mechanical systems whenhandling substances that can contaminate stormwater. Correct anyidentified releases of pollutants.• Remove litter/trash from landscape area to prevent clogging of inletdrains and interference with plant growth.• Manage mosquitos by eliminating any observed standing water; useintegrated pest management (IPM) techniques and seek advice oflocal vector control district.• Maintain green roof aesthetics. Repair any damage or vandalism andremove any trash or debris.• Reconstruct or replace the control measure when it is no longerfunctioning properly.As neededAs neededweekly during peak mosquito season(April-October); as needed thereafter.As neededSee projected lifespan in Appendix B forinformational purposes.Notes:1. Adapted from the City of Portland’s Stormwater Management Manual.Stormwater Quality Design Manual for the Sacramento and South Placer RegionsGR-8 May 2007