atlanta urban design and stormwater
DESCRIPTION
2014 Park Pride Parks and Greenspace Conference Presenters are Johanna McCrehan & Richard Dagenhart,TRANSCRIPT
Johanna McCrehan, Urban Designer, Georgia Conservancy
Richard Dagenhart, RA, Associate Professor of Urban Design, Georgia Institute of Technology
March 31, 2014Park Pride Parks and Greenspace Conference
Urban Designand StormwaterandUrban Design
Georgia Conservancy + Georgia Tech Urban Design Studio
Urban Design and Stormwater
1. Why Stormwater?2. Understanding Stormwater Management3. Conservancy Blueprints + Urban Design Studios
Colonial Homes, Bobby Jones Golf Course and the Peachtree Creek Watershed
Maddox Park, Boone Boulevard and the Proctor Creek Watershed
Pittsburgh, University Avenue and the McDaniel Creek Watershed
Ansley Mall and the Clear Creek Greenway and Watershed
4. Conclusions: Urban Design and Stormwater
STORMWATER IS AN URBAN DESIGN PROBLEM
AND
URBAN DESIGN IS A STORMWATER PROBLEM
Georgia Conservancy
GC - Blueprints for Successful Communities Sponsored by
The Home Depot Foundation The Sartain Lanier Foundation, Inc.
Georgia Tech Urban Design Studio School of Architecture, School of City and
Regional Planning Richard Dagenhart, RA, Associate Professor Dr. Tom Debo, PE, Professor Emeritus
Why Stormwater?
Research-based Blueprints for Successful Communities
Education through partnerships
Statewide initiatives and technical assistance
Regional Atlanta Watersheds:
Upper ChattahoocheeUpper Middle ChattahoocheeUpper FlintUpper OcmulgeeEtowah CoosawatteeUpper Oconee
ARC area
www.atlantaregional.com
GEORGIA’S 52 WATERSHEDS
Understanding Stormwater Management
Stormwater problems have been defined as the control of peak rates of runoff from new urban development
The engineering solution: control post-development runoff from specific rainfall events (5-, 10-, 100-year storms) so they do not exceed pre-development runoff
The design solution: construct a storm detention basin at the development site’s drainage outlet
Criticism of Stormwater Management Practices
Evidence shows that end-of-pipe stormwater solutions do not address the hydrologic changes induced by new development, nor do they consider stormwater quality
The problem in previous approaches was to focus on individual development sites rather than the processes of water flows … as they move from the individual development sites into the larger ecological system of urban waterways or into the equally important migration into ground waters.
Low Impact Development (LID) – The New Approach
Stormwater management focuses on both water quantity and water quality
Stormwater management incorporates natural processes with mechanical processes to design hydrologic solutions
Attention is directed as close to the source of stormwater as possible, not the exit from the site
Stormwater and Urban Design
The LID goal is to allow urban development to occur in most situations, but require that the project be designed to limit hydrologic impacts
The LID objective is to have urban development approximate the hydrologic characteristics of rural or undeveloped land
When LID is broadened beyond a single parcel of land, the design challenge expands from site design to urban design.
Urban Design Studio:Research + Design
Questions
HOW CAN URBAN DESIGN ADDRESS
STORMWATER SOLUTIONS?
HOW CAN STORMWATER ADDRESS
URBAN DESIGN SOLUTIONS?
Stormwater in Context
Four sites along the BeltLine, where the BeltLine Subarea Plans did not specifically address stormwater issues
Pittsburgh, University Avenue and the McDaniel Creek Watershed
Maddox Park, Boone Boulevard and the Proctor Creek Watershed
Ansley Mall and the Clear Creek Greenway and Watershed
Colonial Homes, Bobby Jones Golf Course and the Peachtree Creek Watershed
Urban Design, not engineering, is the focus of the projects – the concern is the relationship of stormwater solutions, environmental quality, and the future of public and private developments for housing, commercial and other uses.
4 SITES
PITTSBURGH, UNIVERSITY AVENUE AND THE MCDANIEL CREEK WATERSHED
EXISTING CONDITIONS
WATERSHED ANALYSIS
HYDROLOGY
PART ONE: PITTSBURGH NEIGHBORHOOD
PITTSBURGH NEIGHBORHOOD – STORMWATER PLAN
GREEN STREETS
PITTSBURGH NEIGHBORHOOD
PART TWO: UNIVERSITY AVENUE
UNIVERSITY AVENUE SITE – SUBDIVISION (LOTS, BLOCKS, STREETS)Pittsburgh block width – 200 ft. – same as New York City – accepts any density
UNIVERSITY AVENUE STRATEGIES
UNIVERSITY AVENUE MASTER PLAN
BIRD’S EYE VIEW OF CENTRAL PARK
CENTRAL PARK – LOOKING SOUTH TOWARD THE BELTLINE
PART THREE: MCDANIEL BRANCH
MCDANIEL BRANCHGREENWAY PLAN
MASTER PLAN
MADDOX PARK, BOONE BLVD AND THEPROCTOR CREEK WATERSHED
EXISTING CONDITIONS
HYDROLOGY
URBAN ANALYSIS
EXISTING PROPOSAL URBAN DESIGN STUDIO PROPOSAL
ANSLEY MALLCLEAR CREEK GREENWAY AND WATERSHED
EXISTING CONDITIONS
EXISTING SITE FEATURES
SCHEMES
STRATEGIES
PROPOSED SECTIONS
SUBDIVISION PLANS AND PHASING
PERSPECTIVES OF NEW WATER SYSTEM
CLEAR CREEK GREENWAY MASTER PLAN
COLONIAL HOMES, BOBBY JONES GOLF COURSE AND THE PEACHTREE CREEK WATERSHED
EXISTING CONDITIONS
URBAN DESIGN AND STORMWATER TACTICS
STORMWATER PERFORMANCE
STORMWATER PERFORMANCE
ECO-GOLF COURSE 100 YEAR STORM EVENT
CONCLUSION 1
EVERY project – public or private, no matter how large or how small, must begin with an understanding of its associated drainage basins.
For urban design – watersheds always come first!!!!
GEORGIA’S 52 WATERSHEDS
CONCLUSION 2
The location of a project in its watershed shapes both urban design and stormwater decisions.
For urban design, site based solutions are the wrong approach. Stormwater policies and regulations must recognize this fact. UNIVERSITY AVENUE,
PITTSBURGH AND McDANIEL BRANCH GREENWAY
CONCLUSION 3
High performance site design, for urban design and stormwater, can combine greenways as incentives for revitalization and new development.
MADDOX PARK, BOONE BOULEVARD AND THE PROCTOR CREEK
WATERSHED
CONCLUSION 4
Urban design can MANAGE stormwater when flooding cannot be eliminated.
Combine retention and detention in greenways, swap land out of flood plains, create new development opportunities.
COLONIAL HOMES, BOBBY JONES GOLF COURSE AND PEACHTREE
CREEK
STORMWATER IS AN URBAN DESIGN PROBLEM
AND
URBAN DESIGN IS A STORMWATER PROBLEM
QUESTIONS?