8525 EVERGREEN WAY BURGER KING 2021-05-10

No. 21 (continued)-Maintenance Standards and Procedures for Bioretention Facilities. Maintenance Recommended Frequency, Condition when Maintenance is Needed Action Needed Component Inspection Routine (Standards) (Procedures) Maintenance Vegetation(cont'd) Weeds M Weeds are present •Remove weeds with their roots manually with pincer-type weeding tools,flame weeders,or hot water weeders as (March-October, appropriate preceding seed •Follow IPM protocols for weed management(see"Additional Maintenance Resources"section for more information on IPM dispersal) protocols) Excessive vegetation Once in early to mid- Low-lying vegetation growing beyond facility edge onto •Edge or trim groundcovers end shrubs at facility edge May and once in sidewalks,paths,or street edge poses pedestrian safety •Avoid mechanical blade-type edger and do not use edger or trimmer within 2 feet of tree trunks early-to mid- hazard or may clog adjacent permeable pavement •While some clippings can be left in the facility to replenish organic material in the soil,excessive leaf litter can cause surface September surfaces due to associated leaf litter,mulch,and soil soil clogging As needed Excessive vegetation density Inhibits stormwater flow •Determine whether pruning or other routine maintenance is adequate to maintain proper plant density and aesthetics beyond design ponding or becomes a hazard for • Determine if planting type should be replaced to avoid ongoing maintenance issues(an aggressive grower under perfect pedestrian and vehicular circulation and safety growing conditions should be transplanted to a location where it will not impact flow) • Remove plants that are weak,broken or not true to form;replace in-kind •Thin grass or plants Impacting facility function without leaving visual holes or bare soil areas •Consultation with a landscape architect Is recommended for removal,transplant,or substitution of plants As needed Vegetation blocking curb cuts,causing excessive sediment •Remove vegetation and sediment buildup buildup and flow bypass Mulch Mulch Following weeding Bare spots(without mulch cover)are present or mulch •Supplement mulch with hand tools to a depth of 2 to 3 inches depth less than 2 Inches • Replenish mulch per O&M manual.Often coarse compost is used in the bottom of the facility and arborist wood chips are used on side slopes and rim(above typical water levels) • Keep all mulch away from woody stems Watering Irrigation system(if Based on Irrigation system present • Follow manufacturer's instructions for O&M any) manufacturer's instructions A Sprinklers or drip Irrigation not directed/located to properly • Redirect sprinklers or move drip irrigation to desired areas water plants Summer watering Once every 1-2 Trees,shrubs and groundcovers in first year of •10 to 15 gallons per tree (first year) weeks or as needed establishment period •3 to 5 gallons per shrub during prolonged dry •2 gallons water per square foot for groundcover areas periods •Water deeply,but Infrequently,so that the top 6 to 12 Inches of the root zone Is moist •Use soaker hoses or spot water with a shower type wand when irrigation system is not present o Pulse water to enhance soil absorption,when feasible o Pre-moisten soil to break surface tension of dry or hydrophobic soils/mulch,followed by several more passes.With this method,each pass increases soil absorption and allows more water to infiltrate prior to runoff •Add a tree bag or slow-release watering device(e.g.,bucket with a perforated bottom)for watering newly installed trees when irrigation system is not present a Frequency:A=Annually;B=Biannually(twice per year);M=Monthly;W=At least one visit should occur during the wet season(for debris/clog related maintenance,this inspection/maintenance visit should occur in the early fall,after deciduous trees have lost their leaves);S=Perform inspections after major storm events(24-hour storm event with a 10-year or greater recurrence interval). IPM-Integrated Pest Management ISA-International Society of Arboriculture Volume V—Runoff Treatment BMPs—December 2014 4-58