critical importance of site design
TRANSCRIPT
Importance of Site DesignTo pervious concrete pavementsBy scott erickson
Why site design matters to you
So What if Site Design Sucks?Who gets the blame?ContractorsSuppliersPervious Industry
Presentation Teaching Goal
How to Avoid Site Design DisastersHow to Prevent bad site designsHow to Communicate and change a
bad designHow to Protect the enormous New
Market From Extinction
Presentation Teaching Goal
What to do about it!Recognize site designsEducate designers well in advanceCommunicate instead of litigate!!!Know your allies, Use team
approach
Swapping Pervious Surface from AC
BAD PERVIO
US DESIGN
BAD PERVIO
US DESIGN
Pervious Clogs
BAD PERVIO
US DESIGN
Pervious Clogs
Blame Pervious
BAD PERVIOU
S DESIGN
Pervious Clogs
Blame Pervious
Sue Contract
or
BAD PERVIOU
S DESIGN
Pervious Clogs
Blame Pervious
Sue Contract
or
PerviousMarket
Dries Up
Really Bad Pervious Design
Photo courtesy of Dr. Heather Brown, Middle Tennessee State University
Do Not Use Pervious As A Trench Drain!
Failed Design AC/Pervious Blend
2900 SF Pervious ConcreteNo back up or overflow
Nearly 15,000 SF Impervious
Site & Grading Design
Asphalt tailings clog pervious
Inadequate backup. Use planter for backup
storage!
Recognize sediment exposure?
!
Prevention better by far!
Asphalt tailings
Oily Grit from AC flows onto pervious
Failed design. No sediment control No back up drainage. Big Lawsuit.
Proper Pervious Design
Have back up drainage Over flow System
Bio SwaleDrain to secondary detention
Grade separationStructures
Drainage Backup SystemsSwale with elevated drain
Drainage Backup SystemsSwale with elevated drain
Site Designs
Grade separation & Overflow
Site Designs
Grade separation & Overflow
Site Designs
Sediment Walls
Site Designs
Curb cut backup drainage
More Pervious Friendly Designs
Isolate Sediment: Sediment trapsFrench DrainLarge non-woody ground cover
Grassy SwaleGrade separation
Barrier curb with grade separation
Design to Protect from Sediment
Retrofitted Asphalt Lot
Replaced with pervious concrete
Sub-Grade Grading Plan
Drainage Backup Systems• Install drainage along steep
slopes.1. Assist drainage down slope2. Minimizes erosion of sub-grade soil
Site Design
Isolate sediment sources
•Bark chips on embankment•Curb and French Drain•Redundancy when able
Intercept Sediment Runoff
French drain used in this application.
Bio swale
Back up Infiltration
Four feet of amended soil below pavement
Bio swale
Trench Drain Isolates Sediment
Impervious
Concrete
Pervious Concrete
Trench
….Drains
Large Scale Sediment Isolation
Large Scale Sediment Isolation
Pervious Alley is Only Collection Point26’ Alley collects water from entire site
Subbase Infiltration vaults/cleanout
Sediment Collection & Cleanout
Stormwater Collection Alley
Mix DesignDependent on; • Owner’s desired look• Function of application
1/4” Crushed 3/8” Round1/8” Crushed
Mix DesignDetermine Application
Sidewalks Pathways
Parking Stalls
Streets
OK to say not a good site
Isolate Sediment
Add landscape fill before pervious• Fill added
before Pervious• Trench drain
isolates impervious from pervious surface
What if bad design already bid?
Notify the Project Engineer of deficiency Recommend NRMCA/ACI standard Contact Local Sponsoring Group or consultant Paulette Salisbury 925-918-0982
Technical Specialist at CA NV Cement Assoc.
Don’t ignore bad design, engineers want it right too!
Importance of Site Design To pervious PavementBy Scott Erickson, NRMCA Pervious Craftsman
[email protected] 415-852-0638