Coastal Best Practices - July21

Coastal Best Coastal Best PracticesPractices

Project OverviewJuly 2010July 2010

Overview• Coastal Louisiana Context• Patterns of Coastal Development• Atlas• Strategies for Community Adaptation• Strategies for Structures• Strategies for Structures• Building Prototypes

C t l Coastal Louisiana Context

The 2005 Hurricanes

Louisiana Speaks: The Vision

New Growth Areas

Economic Development

The Vision: New Growth Areas

JenningsJenningsCrowley

Abbeville New Iberia

The Vision: New Growth Areas

La PlaceKenner/MetairieD ld ill Kenner/MetairieDonaldsonville

Thibodaux

Westwego/MarreroGretna/

M Ci Thibodaux

RacelandAlgiersMorgan City

Larose

The Vision: New Growth Areas

Hammond CovingtonHammond Covington

SlidellMandeville

La PlaceLa PlaceKenner/Metairie

Multiple lines of defense

Special Cases: Economic Devt. Zonesp

Coastal LouisianaLiving with water is a way of life

Levee building in the 1950s - present

• Influenced where growth was possible

• Enabled development on lands constrained by flooding

Levee Farms, Wayne Thiebaud

Man Made and Natural Changes

Matthew Levine

Rebuilding - Holly Beach, Louisiana

Patterns of Coastal Coastal

Development in Development in LouisianaLouisiana

Coastal Development Patterns

• Water and Geology– Riverbanks and Bayous– Coastal

Floodplains– Floodplains • Development patterns form in relation to

water marsh elevation levees andwater, marsh, elevation, levees and roadways

• Produce a unique pattern that needs to be accommodated and understoodaccommodated and understood

Coastal Development Patterns

Small neighborhoods

Small neighborhoods (intersection water, road)

Small neighborhoods

Water serves as the “back yard”

Water is the backyard: boat garden, docks

Road is front yard: garage, garden, neighbors

Bayou: long continuous line of row houses

Bayou: houses perpendicular to water

Urbanization pattern: Old housing on river banks

Economics: Fishing

Infrastructure located on man-made fill

History of housing on the rivers, floating homes

History of stilt houses in the swamps

Water protection: Levee from river/spillway

Beach: roads/houses perpendicular to shoreline

Beach: roads/houses parallel to shoreline

Beach: neighborhoods

Urbanization pattern: Housing along bayous, houses on stilts

Economics: Agriculture, fishing, crabbing, hunting, trapping

Economics: Recreational fishing

Industry

Agriculture

AtlAtlasPurpose is to gather best available

data and make it useful for community planning

Aerial Photography

Source: ESRI

Aerial Photography and City Limits

Source: ESRI and Louisiana GIS Digital Map 2007

Transportation

Source: ESRI

Transportation

Source: ESRI

GIS Data LayersChenier, Delta, and Riverine

Source: Louisiana Office of Coastal Protection and Restoration

Geology – Freshwater Delta & Riverine

Source: Louisiana GIS Digital Map 2007

FEMA 30 Year Floodplain

Source: FEMA

FEMA 30 Year Floodplain

Source: FEMA

Land Use

Source: Louisiana Speaks

Land Use

Source: Louisiana Speaks

50 Year Predicted Land Loss

Source: USGS

50 Year Predicted Land Loss

Source: USGS

Create a readily available planning tool

GIS system is kept up to date with readily available public datay p p y p

Site hosted that provides GIS data and a Storefront for maps

Reduce time necessary to find and access the public data

Strategies forgCommunity Community AdaptationAdaptationHow do you plan a y p

community where there will be occasional flooding?be occasional flooding?

Strategies for Communities

1. Prevent flooding – Build levees; S S fSediment diversion; Strengthen borders of flood prone areas; Armor and fill

2 Adapt to occasional flooding2. Adapt to occasional flooding –Develop community-wide approaches that adapt to occasional floodwaters; Developadapt to occasional floodwaters; Develop resiliency; Minimize property damage from flooding

3. Relocate when absolutely necessary – Relocate part or all of a y pcommunity to a more stable area

1. Prevent Flooding – Global Examples

–Build barriers to fortify borders of–Build barriers to fortify borders of flood-prone areas

–Use natural processes: sediment diversion to rebuild land area; wetland restoration to prevent land lossloss

Netherlands

© Bosch Slabbers

Prevent flooding: barriersNetherlandsSeawall protecting against a storm surge

© Bosch Slabbers

Source: DeltaWorks.org

© Bosch Slabbers

© Bosch Slabbers

Prevent flooding: barriersBangladeshRetractable brick walls can be moved as necessary to protect the community

Source: flickr.com/CLTS

Prevent flooding: barriersCaliforniaRiver island LEVEES protect valuable farmland in central the Sacramento­San Joaquain Delta

Prevent flooding: barriersSand Dunes (natural)

© Bosch Slabbers

Prevent flooding: barriersDikes (man­made)

© Bosch Slabbers

Prevent flooding: barriersDelta Works Netherlands

Major engineering project (1950­1997) to jshorten the Dutch coastline and reduce miles of needed dikesmiles of needed dikes

Source: DeltaWorks.org

Prevent flooding: barriersDelta Works Netherlands

Prevent flooding: LouisianaTeam New Orleans (USACE)

Inner Harbor Navigation Channel (IHNC) S b i i lSurge barrier in coastal Louisiana

flickr./infrogmation

Prevent flooding: barriersSimilar to a floodwall but much larger the IHNC is a surgeSimilar to a floodwall, but much larger, the IHNC is a surge barrier to protect New Orleans and St. Bernard Parish against storm damage, to be completed in 2011

NOLA.com

Prevent Flooding: pumpPump It Up –

Community Level ProtectionProtection

In New Orleans a pump station is  currently under construction that can pump 150,000 gallons of floodwater per second

Prevent flooding – watery cityTigre Delta, ArgentinaThe city relies on waterways and boats for transportation.

Prevent flooding: dredging

.

By preventing flooding upland, the likelihood of flooding increases in low­f f gincome communities nearer the river

NORDELTA, a gated communityNORDELTA, a gated community engineered out of wetlands in 

Tigre, Argentina

Source: Columbia University Planning Studio

Prevent flooding

Adapt to flooding

d fl dAvoid flooding

This aerial image illustrates the disparity between those who live in protected upland communities and those who do not.

Relatively small area protected in Louisiana

Source: Louisiana GIS Digital Map 2007

2. Adapt to Occasional Flooding

• Community approaches to live with • Community approaches to live with occasional flooding

Structural responses that avoid or allow– Structural responses that avoid or allowfloodwaters

– Develop resilience to occasional floodingDevelop resilience to occasional flooding, prepare property and vital infrastructure

– Build strong communities where flooding is aBuild strong communities where flooding is a nuisance, not a disaster

Adapt: controlled floodingNetherlandsCANALS allow for controlled flooding into pasture lands as needed

Adapt: Accept occasional floodwaters

Venice, ItalyR id f fl d

Prepare for Occasional Floodwaters

Residents prepare for floodwaters entering buildings and public spaces

Adapt: activities and attitudesPEOPLE

T i i V iTourists in Venice

Floating markets of Vietnamf

Adapt to occasional flooding

Flooding and a tourism experience

3. Relocate

• Relocating part or all of a community Relocating part or all of a community away from flood danger may be the best option in some scenarios

– Cost to stay > cost to move– Use of temporary or low-cost structuresp y– Seasonal or vacation inhabitation

RelocateMekong Delta, Vietnam:

As part of LIVING WITH FLOODS program, the Vietnamese government has begun relocating flood­prone, high­risk communities to “residential clusters” on higher ground.

RelocatePo Delta, ItalyAbandoned fishing villages

RelocateAfter decades of frequent flooding, water encroachment, and land subsidence, they faced the painful decision of whether to stay or go

Isle de Jean Charles, LouisianaBiloxi­Chitimacha­Choctaw tribe

stay or go.

Images: NOLA comImages: NOLA.com 

RelocateIsle de Jean Charles, Louisiana

Relocate PRE­Gustav POST­Gustav

Louisiana’s coastal land is dynamic and frequently changing

NASA’s Landsat imagery documents land loss due to Hurricane Gustav (2008)

Source: NASA.gov

Historic Land Loss

Source: LSU CLEAR Land Change Module

Historic Land Loss

Source: LSU CLEAR Land Change Module

Historic Land Loss

Source: LSU CLEAR Land Change Module

Historic Land Loss

Source: LSU CLEAR Land Change Module

Historic Land Loss

Source: LSU CLEAR Land Change Module

St t i f Strategies for Structures

How do you build in areas that may flood?that may flood?

Strategies for Structures1. Berm and armor to protect structures and keep water out

2. Elevate with stilts or pole structure to move structures above floodwaters.

3. Flood proofing of buildings so that they can be readily cleaned and returned to active use quickly.

4. Temporary structures that can be rebuilt with relative ease because of lower investment costs.

5. Floating structures either permanently on the water or on land that can float when/if needed.

1. Berm & Armor

FloodwallFloodwall

Sump and pump for internal drainage

Sump and pump for internal drainage

Berm or Berm or LLeveeLevee

One way valveOne-way valve

SewerSewer

One-way valveOne-way valve

1. Berm & Armor

2. Building ElevationCommon StrategyInnovative and traditional development patterns and styles avoid flood damagep y f g

Around the world, entire communities are raised on stilts to avoid structural flooding, while accommodating the occasional land flooding

Tigre, Argentina

Tigre, Argentina

2. Building Elevation

Coastal Louisiana

2. Building Elevation

Pier Foundation

2. Building Elevation

3. Flood Proofing

Maximum ProtectionLevel is Three FeetMaximum ProtectionLevel is Three FeetLevel is Three FeetLevel is Three Feet

One-Way ValveOne-Way ValveSewerSewer

Closures for OpeningsClosures for Openings

Flood Proofed WallsFlood Proofed Walls

One-Way ValveOne Way Valve

Dry Floodproofing

3. Flood Proofing

O i t L tOpening to LetF d UtilitiF d Utiliti Opening to LetWater In

Opening to LetWater In

Furnace and UtilitiesRelocated

Furnace and UtilitiesRelocated

Appliances Moved or Wrappedin Waterproof Bags

Appliances Moved or Wrappedin Waterproof Bags

Wet Floodproofing

3. Flood Proofing

Flood Proof Walls, Move HVAC & Electrical

Install Sewer Backflow Openings, Foundation Move HVAC & Electrical Valve

4. Temporary Structures

4. Temporary Structures

http://tinyhouseblog.com/pre-fab/habitaflex/p y g p

5. Floating StructuresHybrid foundations allow 

buildings to float Massbommel NetherlandsMassbommel, Netherlands

5. Floating Structures

© Bosch Slabbers

5. Floating StructuresPortland, Oregon Oaks Park Roller Rink 

The skating rink was built in 1905 in a fl d l i Aft fl d i 1948 i dfloodplain. After a flood in 1948 ruined the rink's wood floor, the rebuilt floor was designed to float in the event of another flood. Since then, the floating floor has f f g fsurvived two serious floods in 1964 and 1996. 

Source: http://myweb.msoe.edu/~westr/pdxoaks.htm

5. Floating Structures

The FLOAT House New OrleansThe FLOAT House, New Orleans

i iBuilding Prototypesyp

Modules that can be used in planning exercisesplanning exercises

Purpose is to match building strategies with community strategies with community

protection

Traditional Compact  Traditional Compact  Waterfront Residential Waterfront Commercial Community CenterpResidential ‐1 Story

pResidential ‐2 Stories

y

Main Street Commercial‐ Main Street Commercial‐ Main Street Commercial‐ Multifamily Waterfront Hotel 1 Story 2 Stories 3 Stories and Restaurant

House  Boat

Prototype Thumbnails

Building Prototype Modeling

Building Prototype Modeling

ROI Model (FA)

• Each building has a gprototype building sheet

• Input physical characteristics of “prototype building”prototype building

• Includes zoning and gdevelopment standards and other regulations or ginsurance issues

What can the ROI Model tell?• Financial

Feasibility– Zoning– Flood Protection

Strategy

S t i bilit• Sustainability• Plan Feasibility• Tax Revenue ofTax Revenue of

Plan• Transportation

NeedsNeeds• School Enrollment• Housing Suitability• Etc.

Closed Foundation with Vent Holes for FloodwatersElevated 8 Feet

Traditional Compact Residential – 1 Story

Elevated Foundation with Grade BeamsElevated 15 Feet

Traditional Compact Residential – 2 Stories

Elevated Foundation with Grade BeamsElevated 8 Feet

Waterfront Residential

Elevated Foundation with Grade BeamsElevated 15 Feet

Main Street Commercial – 1 Story

Open Foundation with Grade Beam Closed Foundation with Crawl SpaceOpen Foundation with Grade Beam Closed Foundation with Crawl SpaceElevated 15 feet Elevated 8 feet

Building Foundation Type Options

Source: FEMA Publication, Recommended Residential Construction for Coastal Areas, December 2009