better site design sustainability & stormwater shohreh karimipour, p.e. nysdec
TRANSCRIPT
Better Site DesignBetter Site Design Sustainability & Sustainability &
StormwaterStormwaterShohreh Karimipour, P.E.Shohreh Karimipour, P.E.
NYSDECNYSDEC
Presentation OutlinePresentation Outline
Better Site Design Better Site Design (LID, Sustainability, Environmental (LID, Sustainability, Environmental
Design,Design,Green Infrastructure)Green Infrastructure) CategoriesCategories
Preserve Natural Features Preserve Natural Features Reduce Impervious CoverReduce Impervious Cover Better Integrate Stormwater Better Integrate Stormwater
TreatmentTreatment PrinciplesPrinciples
Specific PracticesSpecific Practices
Better Site DesignBetter Site Design
◄Preserve Preserve undisturbed undisturbed areas areas ◄ConservatiConservation Designon Design
An approach to development An approach to development design design
that seeks to:that seeks to:
Better Site DesignBetter Site Design
◄Reduce Reduce impervious coverimpervious cover
RoadsRoads Parking lotsParking lots DrivewaysDriveways
An approach to development An approach to development design design
that seeks to:that seeks to:
Better Site DesignBetter Site Design
◄Use Use pervious pervious areas for areas for stormwater stormwater treatmenttreatment
An approach to development An approach to development design that seeks to:design that seeks to:
Good Drainage ParadigmGood Drainage Paradigm
Conventional Site DesignConventional Site Design
Collect Collect Concentrate Concentrate Convey Convey Centralized Centralized ControlControl
Credit: HWG
Rain Garden Rain Garden
Treatment Train ApproachTreatment Train Approach
Bioretention CellStorm Drain System
Bioretention Cell
Flow Path
Grass Swale Grass Filter Strip
Credit: HWG
NYS Standard PracticesNYS Standard Practices
NYS Stormwater Design Standard Overlap ( )with BSD or LID Practices
BSD Category oneBSD Category one
Avoid the Impacts:Avoid the Impacts: Preserve Natural Features Preserve Natural Features
and and
Use Conservation DesignUse Conservation Design
Preservation of Preservation of Undisturbed AreasUndisturbed Areas
Delineate on plans / in the Delineate on plans / in the field field Place in permanent Place in permanent conservation:conservation:Undisturbed Undisturbed forestforestNative Native vegetationvegetationStream Stream corridorscorridorsWetlandsWetlandsNatural terrain Natural terrain – hydrology– hydrology
US Forest Service
Preservation of BuffersPreservation of Buffers
•Delineate buffers •Protect during:
•Design•Construction•Home occupancy
•Non-structural stormwater infiltration•Consult/amend local codes
Reduction of Clearing & Reduction of Clearing & GradingGrading
Establish Limit of Disturbance for:•Buildings •Roads•Utilities•Wastewater•StormwaterUse site foot-printing Limit mass gradingUse open space or cluster development
GCSWCD
Locate Sites in Less Locate Sites in Less Sensitive AreasSensitive Areas
Locate development to Locate development to avoid: avoid: Erodible Erodible
soilssoilsFloodplainsFloodplainsSteep Steep slopesslopesWetlandsWetlandsMature Mature ForestsForestsCritical Critical habitathabitat
Open Space DesignOpen Space Design
Use smaller Use smaller lot sizeslot sizesReduce Reduce impervious impervious covercoverProvide Provide more more undisturbed undisturbed open spaceopen spaceProtect Protect water water resources resources
Saves costsSaves costsreduces reduces gradinggradingreduces reduces infrastructure infrastructure
Successful Successful ExamplesExamples
Preserves conservation areasPreserves conservation areasPreserves natural hydrologyPreserves natural hydrology
Open Space DesignOpen Space Design
BSD Category TwoBSD Category Two
Reduce the Impacts:Reduce the Impacts:Reduce Impervious Reduce Impervious
SurfacesSurfaces
Design Design according to according to density and density and traffic demandtraffic demand
Minimize Minimize roadway lengths roadway lengths
Minimize Minimize roadway widthsroadway widths Consult / amend Consult / amend
local codeslocal codes Use AASHTO* Use AASHTO*
guidelinesguidelines Use alternative Use alternative
road patternsroad patterns
Roadway Roadway ReductionReduction
Shared Shared drivewdrivew
ayay
Planning Board Provide Model
Shared Driveway Agreement to applicants
Alternative materialsAlternative materials Shorter setbacksShorter setbacks Planning Board
Encourage shared driveways
Use Model Shared Driveway Agreement
Encourage pervious materials on pull offs for emergency
Driveway Reduction Driveway Reduction
Town of WappingerTown of Wappinger §214-74§214-74 requires cul-requires cul-de-sacs be de-sacs be circularcircular with with no center islandno center island
REVISE CODE to require developers REVISE CODE to require developers demonstrate no alternative to cul-de-sac; demonstrate no alternative to cul-de-sac; minimized paved area minimized paved area
Minimize Cul-de-SacsMinimize Cul-de-Sacs
What about New York State What about New York State Highway Law?Highway Law?
New Town roads Right-of-way = New Town roads Right-of-way = 49.5 feet49.5 feet
If not, must petition Commissioner If not, must petition Commissioner of Transportationof Transportation
Recommend: Keep 49.5 minimum Recommend: Keep 49.5 minimum – also needed for– also needed for stormwater and stormwater and snow removal.snow removal.
ButBut limit limit pavement to pavement to travel-way. travel-way.
Sidewalk ReductionSidewalk Reduction
Use alternative designsDesign on one side of street onlyUse alternative surfaces
Building Building Footprint Footprint ReductionReduction
BenefitsBenefits::Reduces Reduces impervioimpervious cover us cover & & pollutantpollutantss
Parking ReductionParking Reduction Compact Compact car spacescar spacesMinimal Minimal stall stall dimensionsdimensionsEfficient Efficient parking parking laneslanesParking Parking decksdecksPorous Porous paving in paving in overflowoverflowEliminate Eliminate unneeded unneeded spacesspaces
BSD Category 3BSD Category 3
Manage the Impacts: Manage the Impacts: Better Integrate Better Integrate
Stormwater TreatmentStormwater Treatment
Open Vegetated Open Vegetated ChannelsChannels
Convey & Convey & treat runofftreat runoff
Natural Natural drainage drainage pathspaths
Properly Properly designed & designed & constructed constructed channelschannels
On certain On certain sites use in sites use in street right-street right-of-way of-way
Vegetated Buffer/Filter StripsVegetated Buffer/Filter Strips
Forested Forested areasareas
Stream Stream buffersbuffers
Vegetated Vegetated filter stripsfilter strips
Treat & control runoff Treat & control runoff with:with:
Plant trees:•In stormwater management practices (where appropriate)•In landscape plans•Revegetate buffer areas . . .
Tree Planting
InfiltrationInfiltration
PedestriaPedestrian areasn areas
Overflow Overflow parkingparking
ResidentiResidential al drivewaysdriveways
Green Green StreetsStreets
Use permeable Use permeable pavement/pavers where site pavement/pavers where site conditions are appropriate:conditions are appropriate:
Stream Daylighting for Stream Daylighting for RedevelopmentRedevelopment
Increases Increases aesthetics aesthetics Improves water Improves water qualityqualityPrevents flooding Prevents flooding – increased – increased storage storage Improves in-Improves in-stream habitatstream habitat Increases public Increases public useuseIncreases Increases property valuesproperty valuesSunlightSunlight
Redevelopment ProjectsRedevelopment Projects Chapter is part of Design Manual (Chapter 9)Chapter is part of Design Manual (Chapter 9) Permit coverage in 5 business days Public NoticedPermit coverage in 5 business days Public Noticed
Application CriteriaApplication Criteria An already impervious area reconstructed, andAn already impervious area reconstructed, and There is inadequate space for controlling stormwater There is inadequate space for controlling stormwater
runoff, orrunoff, or There are physical constraints on the site There are physical constraints on the site
Sizing CriteriaSizing Criteria 25% reduction in impervious area 25% reduction in impervious area Treat 25% WQv with standard practice Treat 25% WQv with standard practice Treat 75% of WQv with Alternative PracticesTreat 75% of WQv with Alternative Practices Combination of all the aboveCombination of all the above
PerformancePerformance Criteria Criteria Alternative Practices (Alternative Practices (Cisterns, Rain gardens, Green Cisterns, Rain gardens, Green
roofs, Stormwater planters, Porous and permeable roofs, Stormwater planters, Porous and permeable pavements, Select proprietary products pavements, Select proprietary products ))
ApplicationsApplications Capture and store stormwater runoff Capture and store stormwater runoff
for reuse or irrigationfor reuse or irrigation LimitationsLimitations
MaintenanceMaintenance Water use managementWater use management Cold Climate Cold Climate Community AcceptanceCommunity Acceptance
Sizing Sizing based on the contributing based on the contributing area:area: Vol = WQv * 7.5 gals/ftVol = WQv * 7.5 gals/ft33
CisternsCisterns
ApplicationsApplications Manage and treat small volumes of runoffManage and treat small volumes of runoff Use conditioned planting soil bed and planting Use conditioned planting soil bed and planting
materialmaterial Filter runoff stored within a shallow depressionFilter runoff stored within a shallow depression
LimitationsLimitations Steep slopesSteep slopes Compacted and clay soilsCompacted and clay soils Sheet / shallow concentrated flowSheet / shallow concentrated flow Roof drain downspout < 1,000 square feetRoof drain downspout < 1,000 square feet Heavy tree cover or root systems Heavy tree cover or root systems
Sizing based on WQ volume reductionSizing based on WQ volume reduction
Rain GardensRain Gardens
Green RoofsGreen Roofs ApplicationsApplications
Reducing total annual runoff volumes Reducing total annual runoff volumes Insulation from the heat and cold, energy Insulation from the heat and cold, energy
conservationconservation Reduce the urban heat island effect Reduce the urban heat island effect Creates habitat, aesthetically pleasing Creates habitat, aesthetically pleasing
LimitationsLimitations Damage to or failure of waterproofingDamage to or failure of waterproofing plant survival plant survival MaintenanceMaintenance
Sizing based on WQv reduction, soil Sizing based on WQv reduction, soil engineering, evapotranspirationengineering, evapotranspiration
Stormwater PlantersStormwater Planters ApplicationsApplications
On-site soils, high GW table not suitable for infiltrationOn-site soils, high GW table not suitable for infiltration Reduction of discharge volume, velocity from impervious Reduction of discharge volume, velocity from impervious
areasareas Aesthetic landscape element and micro-habitatAesthetic landscape element and micro-habitat
LimitationsLimitations Not designed to treat roadway runoffNot designed to treat roadway runoff Overflow needs to be directed to a Overflow needs to be directed to a
secondary treatment systemsecondary treatment system Sizing Sizing
WQV based on surface area, depth WQV based on surface area, depth
Of soil medium, hydraulic conductivityOf soil medium, hydraulic conductivity
Photo Copyright 1999, Center for Watershed Protection
Permeable PavingPermeable PavingPermeable PavingPermeable Paving
http://www.wbdg.org/design/lidtech.php
Porous PavementPorous PavementPorous PavementPorous Pavement
Photo Copyright 1999, Center for Watershed Protection
Permeable PavingPermeable PavingPermeable PavingPermeable PavingPermeable PaversPermeable PaversPermeable PaversPermeable Pavers
ApplicationsApplications low-traffic areaslow-traffic areas overflow parkingoverflow parking Residential single family homeResidential single family home GW recharge GW recharge
LimitationsLimitations suitability of the site gradessuitability of the site grades SubsoilsSubsoils Drainage characteristicsDrainage characteristics Groundwater conditionsGroundwater conditions
Sizing Sizing based on surface areabased on surface area
Summary:Summary:
Improve development Improve development projects & communities with projects & communities with Better Site DesignBetter Site Design Preserve undisturbed areasPreserve undisturbed areas
Reduce impervious coverReduce impervious cover
Use pervious areas for Use pervious areas for stormwater treatmentstormwater treatment
Achieve a marketable, cost-Achieve a marketable, cost-effective producteffective product
Questions?Questions?
Shohreh Karimipour, [email protected]
(518) 402-8102
Angus Eaton, [email protected]
(518) 402-8123