Stormwater Opportunities: Spirit of Charity, Lafitte Greenway, Armstrong Park by Greater New Orleans Foundation

07 OCTOBER 2020

Stormwater Opportunities:

Spirit of Charity, Lafitte Greenway, Armstrong Park

October 7, 2020 Dear Friends: New Orleans is no stranger to rain. In fact, our region is one of the rainiest in the country. Not surprisingly, fighting stormwater and managing flooding have dominated the design and development of our city's infrastructure since its founding over 300 years ago. Since Katrina, we have seen that storms have intensified due to climate change. And the 2020 hurricane season has reminded us all too frequently of our vulnerability. Starting in 2010, the Greater New Orleans Foundation (GNOF) began working aggressively to build the movement to live better with water, recognizing that new solutions to our water challenges are urgently required. We can no longer pipe and pump our way out of our problems and desperately need to incorporate green infrastructure principles to manage stormwater and reduce the subsidence that destroys our streets and makes flooding worse. That is why we are proud to have commissioned Waggonner & Ball Architecture/Environment to produce this Stormwater Opportunities: Spirit of Charity, Lafitte Greenway, Armstrong Park Study. It is our latest step towards implementing a holistic and resilient model for improving water management and alleviating flooding in the urban core of New Orleans as envisioned in the Greater New Orleans Urban Water Plan. Ten years ago, GNOF and the Idea Village launched the Water Challenge, an entrepreneurial competition that supports social enterprises that develop market-based solutions to the region's water challenges. Today, the Water Challenge is managed by Propeller with support from GNOF. In 2013, GNOF launched the Urban Water Series and began hosting citywide conversations about our city's water challenges and possible solutions. In 2014, we brought 26 leaders from the city government, including then Councilmember LaToya Cantrell, environmental non-profits, and neighborhoods vulnerable to flooding to visit three cities that successfully scaled green infrastructure and stormwater management strategies. Since 2016, in partnership with the City of New Orleans, we have held master classes and public lectures with experts to train planners, engineers, landscape designers, architects, and policymakers from across the Greater New Orleans region on best practices for implementing green infrastructure. During the past decade, GNOF has also invested $3.2 million to support non-profit and communitybased organizations working to advance our region's efforts to live better with water. In 2016, GNOF made its first grant to support the Greater Treme Consortium (GTC). This community-based organization has been an advocate for improved social, economic, and cultural conditions in the Historic Treme neighborhood, which has been the victim of injustices in planning and development and plagued by localized flooding and subsidence. GTC's Waterwise Treme initiative has engaged more than 200 residents who have designed and implemented their own green infrastructure projects, including constructing the biggest planter box in the city at the Treme Center that can capture 9,000 gallons of stormwater from its roof! GNOF helped support the New Orleans Redevelopment Authority's Community Adaptation Program, which funds residential green infrastructure projects for low-to mid-income families in Gentilly. GNOF has also supported the City of New Orleans' efforts to ensure that disadvantaged business enterprises (DBEs) have access to the more than $260 million in green infrastructure projects that the Cantrell Administration has put out for bid, such as the Gentilly Resilience District,

City Park, Pontilly Neighborhood Stormwater Network, and Hagan-Lafitte Basin flood mitigation initiatives. GNOF has commissioned the Water Environment Federation and Center for Watershed Protection to develop an entry-level green infrastructure certification program so that more of our region's disconnected workers can be successfully trained to access the new jobs generated by these vital projects. In 2018, GNOF led the Spirit of Charity Innovation District's strategic planning process, including the neighborhood surrounding the former VA Hospital site and Duncan Plaza. The plan envisions a robust, dynamic, job-creating District, where innovation and equity are at the forefront. It also calls for incorporating green infrastructure, particularly in Duncan Plaza, that can serve as a model for environmental sustainability and stormwater management. Earlier this summer, in partnership with the Sewerage and Water Board and the City of New Orleans, GNOF launched the "Every Drop Makes a Difference" campaign to inform residents about why our City floods and what various organizations are doing to reduce flooding, to promote green infrastructure, and to identify the actions each resident and business can take to reduce runoff. It is for organizations like the Greater Treme Consortium and residents of neighborhoods like Treme, Gentilly, and Pontilly and many others across our region that GNOF undertakes this work. This Stormwater Opportunities: Spirit of Charity, Lafitte Greenway, Armstrong Park Study provides recommended strategies to dramatically improve our stormwater management and decrease flooding that will benefit neighborhoods from the Spirit of Charity Innovation District to Mid-City to Treme. The findings demonstrate that we can create flood mitigation projects that will slow stormwater runoff, store it, and let it slowly enter the drainage system over time, potentially reducing the flooding caused by a ten-year storm by 39 percent. This study was made possible with generous financial support from the Berger Companies, Tommy Coleman, Flower Holdings, Gallo Mechanical, Valentino Hospitality, HRI Lodging, J Hospitality and Development, Laitram, the Roosevelt Hotel, and Tulane University. Flooding in our region will not be solved by one entity alone, but through a concerted, cross-sector effort of residents and businesses taking action on their own property, advocacy and support from community-based organizations, as well as large-scale, publicly-funded green infrastructure projects like those outlined in this report. If these recommendations are fully implemented, they will produce what our study's authors, David Waggonner and Ramiro Diaz, have called "heroic flood mitigation." That is exactly what New Orleans needs right now. Andy Kopplin

President and CEO Greater New Orleans Foundation Doris Z. Stone Chair in Philanthropic Leadership

I Defining the Problem II Design Scenarios III Proposed Approach IV Appendix

Vision Existing water challenges: Runoff and drainage

Goal: Reduce flooding in the district

Build upon the Greater New Orleans Urban Water Plan + City of New Orleans Resilience & Sustainability Goals Holistic stormwater management strategies + urban design create value and safety

Overview Commissioned by the Greater New Orleans Foundation and produced by Waggonner & Ball Architecture/Environment, the Stormwater Opportunities: Spirit of Charity, Lafitte Greenway, Armstrong Park Study is the next step towards implementing a holistic and resilient model for improving water management and alleviating flooding in the urban core of New Orleans. Recent storm events have impacted residents, interrupted businesses, and negatively affected the local economy. This study builds upon the Living With Water® strategies of the Greater New Orleans Urban Water Plan and the City of New Orleans Department of Public Works and Office of Resilience & Sustainability ongoing green infrastructure investments. Under Mayor Cantrell’s leadership, $260 Million of resilience projects and initiatives are underway around the city. This study provides a conceptual design basis for future investments that will offer significant flood mitigation if implemented. In the Downtown Central Business District, runoff from the highly impervious land cover, exacerbated by the hydraulic pressure coming from tall buildings, regularly overwhelms the undersized drainage infrastructure. Runoff from downtown impacts downstream neighborhoods in the Drainage Pump Station 2 basin, including Mid-City, Tulane-Gravier, and Treme. Slowing and storing runoff on the high ground reduces flooding in lower-lying neighborhoods. This study identifies several opportunities to capture large volumes of rainfall on publicly held land using Living With Water® urban water design strategies, such as water squares and parks, water features, bioswales, tree plantings, subsurface storage, and permeable paving. The team explored over 25 design scenarios, using Hydrologic and Hydraulic modeling feedback to analyze, refined, and illustrate impacts. Two refined design scenarios offer a range of phased implementation options for each of the two focus areas:

Extended study area

1. Spirit of Charity, Duncan Plaza, and the VA Hospital Site 2. Armstrong Park and Lafitte Greenway

Extended study area

Overview For the first study area, the Spirit of Charity, Duncan Plaza, and VA Hospital site, the design team used previously completed studies, including the Downtown Development District’s VA Complex Study and Duncan Plaza Master Plan as a starting point. The Minimum scenario assumes urban stormwater interventions are located only on land controlled by the city with minimal demolition of auxiliary structures on the VA site. The Proposed scenario imagines a completely redesigned Duncan Plaza, select demolition of non-historic VA buildings, and significant water storage targets.

BAYOU ST JOHN

At the Lafitte and Armstrong Park study area, the team refined and expanded design proposals from the Greater New Orleans Urban Water Plan. The Minimum scenario utilizes city-owned land to create subsurface and surface water detention within the former Carondelet Canal right-of-way. The more ambitious Proposed scenario extends the scope of the intervention to Bayou St. John, creating a waterway that both provides dramatic stormwater storage capacity and a new urban amenity.

As with any major construction project, robust community engagement, especially among those residents most vulnerable to flooding, will be critical to successful project design and implementation. Finally, we recognize that this study has a limited scope and is part of a larger movement of work that has been done and continues to be done by homeowners, business owners, non-profit and community-based organizations, neighborhood associations and revitalization groups to better “live with water”. We are committed to ensuring that any effort to move forward on one or more of these recommendations will build on the work of this larger movement.

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The design team analyzed each of the scenarios in a 10 Year Stom Event, using the Storm Water Management Model (EPA SWMM) generously provided by the City of New Orleans. This digital Hydrologic and Hydraulic model processes stormwater flows across the land surface and in pipes and canals, simulating flooding. The combined impact of the Minimum scenario is a 12% reduction of flood volume across the study area, as compared to existing flooding. The combined impact from the more ambitious Proposed scenario is a heroic 39% reduction of flood volume. This translates to significantly lower water levels in pipes, canals, and streets, thereby alleviating the overburdened drainage system and potentially decreasing damage to property.

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While the optimal results will be achieved only if all of the modeled projects are implemented, many much-discussed proposals for Duncan Plaza, Armstrong Park, and the extension of the Lafitte Greenway from Claiborne Avenue to Basin Street, if implemented, could incorporate recommendations contained in this study and produce meaningful flood mitigation benefits in a matter of years. Where impediments like the need to demolish auxiliary structures on the VA site may preclude immediate action on other proposed projects, with proper long-term planning, and a commitment to realizing the vision contained in these recommendations, this dramatic reduction in flooding in some of our city’s most historic and vulnerable neighborhoods can be achieved.

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Flood Reduction Volume from 10-year, 24-hour Design Storm Baseline Base Flood Volume

Minimum Scenario Flood Volume

Existing Flood Volume Total Minimum Scenario Flood Reduction Proposed Scenario Flood Reduction

Proposed Scenario Flood Volume

137.6 Ac Ft - 16.9 Ac Ft (-12%) - 53.2 Ac Ft (-39%)

Defining the Problem

Urban Water Challenges Living With WaterÂŽ

Flooding is caused by runoff & overwhelmed drainage systems.

Subsidence results from excessive groundwater pumping.

Water assets are hidden behind walls, buried underground, or pumped out of sight.

Precipitation Events New Orleans

In New Orleans, the 10 year, 24 hour precipitation event is around 8.5 inches of rain. This means that every year there is around a 10% chance that 8.5 inches of rain will fall over a 24 hour period. Within that day most of that 8.5 inches will fall over a more intense 1 to 2 hour period. In the 10 year 24 hour storm:

Design Precipitation Events

Historic Precipitation Events, 2009 -2019

Major rain days over the last TEN years as measured at the NOAA Audubon Park rain gauge

10 inches in 24 Hours 25 Year (5% Annual Chance) Figure 2: Hyetograph of Rainfall for 10-year 24-hour design storm for New Orleans area.

9.26 inches: Hurricane Isaac, 8/29/12

8.5 inches in 24 Hours 10 Year (10% Annual Chance) This is the design event used in the stormwater model

1,128 Ac Ft of rain will fall on

the combined impact area of the project.

8.1 inches: Tropical Storm Lee, 9/3/11 +/-8.0-10.0 inches: Rain, 8/5/17 *

7.2 inches: Rain, 12/12/2009 7.1 inches: Rain, 07/11/2019

138 Ac Ft of that rainfall volume

will become floodwater.

5.4 inches in 24 Hours 2 Year (50% Annual Chance)

To compare the results with real and known storm events, Procella downloaded rainfall short interval data at the New Orleans airport in Kenner, Louisiana from wunderground.com. The storms on the following dates were analyzed: June 10, 2020, July 10, 2019, and May 12, 2019. Procella tried to pull August 5th, 2017 storm but the data didn’t show significant rainfall at the New Orleans airport where the short interval data is collected. Procella tried to collect short term data closer to the project site, however, historic data hourly data wasn’t publicly available. Upon comparison of the three real storms, the July 10th, 2019 storm was used because it’s peak intensity of 7 inches/hr for a 5-minute period was closest toFigure the design storm’s peak intensity 7.42 inches/hr for a 5-minute The hyetographs and 2: Hyetograph of Rainfall forof 10-year 24-hour design storm forperiod. New Orleans area. Hyetograph, 24 Hour Design rainfall data for the July10 10thYear, , 2019 storm is shown in FiguresStorm 3 and 4. in New Orleans To compare the results with real and known storm events, Procella downloaded rainfall short interval data at the New Orleans airport in Kenner, Louisiana from wunderground.com. The storms on the following dates were analyzed: June 10, 2020, July 10, 2019, and May 12, 2019. Procella tried to pull August 5th, 2017 storm but the data didn’t show significant rainfall at the New Orleans airport where the short interval data is collected. Procella tried to collect short term data closer to the project site, however, historic data hourly data wasn’t publicly available. Upon comparison of the three real storms, the July 10th, 2019 storm was used because it’s peak intensity of 7 inches/hr for a 5-minute period was closest to the design storm’s peak intensity of 7.42 inches/hr for a 5-minute period. The hyetographs and rainfall data for the July 10th, 2019 storm is shown in Figures 3 and 4.

5.7 inches: Rain, 8/27/19

Figure 3: Hyetograph for July 10th, 2019 storm based on data from the New Orleans airport in Kenner, LA

Hyetograph for Storm Event on 10 July 2019, MSY Airport Data

Procella Design, LLC

1106 General Taylor St New Orleans, LA 70115

Credit: Procella 2256144280

Figure 3: Hyetograph for July 10th, 2019 storm based on data from the New Orleans airport in Kenner, LA

Procella Design, LLC

0 inches

* estimated amount, not measured at NOAA Audubon Park rain gauge

1106 General Taylor St New Orleans, LA 70115

2256144280

Historic Approach

Greater New Orleans Urban Water Plan

Stormwater Volume

STORE

FLOOD

PUMP

pipes / canals

Duration

Pump

TYPICAL STORM can raintake CURVE

The region the �irst step STOREsystems FLOOD from pump��irst drainage towards an integrated living water PUMP system by replacing paved areas wherever possible with vegetated and pervious surfaces that absorb

pumps

levee

Drain

Stormwater Volume

rain is, hundreds and aves of a tree. That ousands of these “leaves” can be created ross the region’s 155 square miles. Each ows and absorbs water where it falls, d the water that does run off is cleaner d reduced in volume. Just as a tree’s aves provide bene�its for the surrounding vironment by cleaning the air, by groundwater sorbing water, by providing shade, and providing homes for variegated �lora and Pave + Pipe una, so too will the addition of “leaves” today’s drainage systems provide uanti�iable and long�term bene�its to the ople and environment of the region.

Duration

INCREASE PUMPING pumps

Duration

Paradigm Shift

Living With WaterÂ® Approach

Stormwater Volume

rain pumps INCREASE PUMPING

levee groundwater

Slow

Duration Store & Use

Stormwater Volume

SLOW, STORE & USE

Duration

Drain

(when necessary)

Living Water System

Greater New Orleans Urban Water Plan

Credit: H+N+S

Impacted Neighborhoods and Stakeholders Neighborhoods Esplanade Ridge / Treme Civic Association Mid City Neighborhood Organization St. Bernard-N. Rampart Business and Residential Alliance, Inc Historic Faubourg Treme Association. Faubourg Lafitte Tenants Association Greater Treme Consortium Incorporated Historic Faubourg Treme Association Faubourg Tulane Gravier Neighborhood Alliance Lower Mid-City Neighborhood Association Vieux Carre Property Owners, Residents & Associates INC Warehouse District Neighborhood Association Revitalization BioDistrict New Orleans Broad Community Connections Broad Street Main Street Claiborne Avenue Alliance North Rampart Main Street Phoenix of New Orleans Ujamaa Economic Development Corporation Businesses French Quarter Business Association Decatur Street Merchant Association Downtown Development District Magazine St. Merchants Association Parks Friends of Laffite Greenway Lafayette Square Association

Impacted Neighborhoods and Stakeholders Project Impact Area Pumping Station Watershed Planning District Boundary Project Area

LAKE

Areas and Stakeholders

PONTCHARTRAIN

DPS6

Duncan Plaza & VA Hospital Site A

Duncan Plaza

Lafayette Square

City Hall

Civil District Court

Superdome

University Medical Center & Veterans Affairs

LSU Health Sciences Center

Tulane University Medical Center

Charity Hospital

Charity School of Nursing (Delgado)

VA Hospital Site

New Orleans Public Library

Downtown Development District

Armstrong Park & Lafitte Greenway 12

Friends of Lafitte Greenway

Congo Square Preservation Society

Louis Armstrong Park

Historic Faubourg Treme Assoc.

Iberville Housing Development

Faubourg Lafitte

Mahalia Jackson Theater

Municipal Auditorium

Treme Center

Vieux Carre Commission

DPS4

DPS7

DPS3 B A Y O U S T. J O H N DPS2

MID-CITY

AC CT IMP PROJE

T AREA 17

TULANE/GRAVIER

TREME/LAFITTE 15

4 18

5 19

Duncan Plaza/VA Project Area

Armstrong/Lafitte Project Area

20 14

FRENCH QUARTER

3 A

CENTRAL BUSINESS DISTRICT B

C JE

E AR

SS MI

ISS

RIV

Hydrology (Surface Flow) Project Impact Area Pumping Station Watershed Planning District Boundary Project Area

LAKE

Surface Flows

PONTCHARTRAIN

Back Slope Armstrong/Lafitte Project Area

Duncan Plaza/VA Project Area

Mid Slope

SS MI

Up Slope

ISS

RIV

Stormwater System Project Impact Area Pumping Station Watershed Planning District Boundary Project Area

LAKE

Surface Flows

PONTCHARTRAIN

Pipes, Culverts & Canals Pump Station

DPS6 DPS4

DPS7

DPS3 B A Y O U S T. J O H N DPS2

MID-CITY

DPS1

TREME/LAFITTE

TULANE/GRAVIER

Armstrong/Lafitte Project Area

Duncan Plaza/VA Project Area

FRENCH QUARTER

CENTRAL BUSINESS DISTRICT

O PR

T AC

SS MI

ISS

RIV

Proposed Water Storage Retrofits Project Impact Area Pumping Station Watershed Planning District Boundary Project Area

LAKE

Pipes, Culverts & Canals

PONTCHARTRAIN

Pump Station Proposed Stormwater Retrofits

DPS6 DPS4

DPS7

DPS3 B A Y O U S T. J O H N DPS2

MID-CITY

DPS1

TREME/LAFITTE

TULANE/GRAVIER

Armstrong/Lafitte Project Area

Duncan Plaza/VA Project Area

FRENCH QUARTER

CENTRAL BUSINESS DISTRICT

O PR

T AC

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Existing Flooding

Street flooding in the CBD on 04 April 2019 Credit: Chris Granger. NOLA.COM

Street flooding on Canal Street on 10 July 2019 Credit: Chris Granger. NOLA.COM

Street flooding at Hagan and Lafitte Streets, July 2012 Credit: Waggonner & Ball

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Existing Elevation Sections

height in ft.

LSU HSC Campus

UMC Site Beyond VA Site Beyond

Section 1: Near Poydras St, with 80 times vertical exaggeration height in ft.

UMC

Section 2: Near Canal St, with 80 times vertical exaggeration 2 1

Parks Flooding Culverts

Section Locations

The drawings above are vertically exaggerated 80 times, and show the general slope of land down and away from the levees that bound the Mississippi River. Small changes in elevation are imperceptible to the eye, but visibly impact the flow of stormwater. For example, areas that are slightly lower than surrounding areas function as bowls, collecting water that depends entirely on the existing system to drain. Flooding occurs in these low-lying areas if the

subsurface drainage system is unable to handle the volume of stormwater. A nuanced study of drainage is necessary in order to understand existing conditions and to propose design solutions that are tailored to fit specific locations.

Elevation Impact Areas

Historic Map Colorized by Waggonner & Ball

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MIS SIS SIPPI RIVER

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New Orleans, 1828

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MIS SIS SIPPI RIVER

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TREME - L AFIT TE

CENTRAL BUSINES S DISTRICT

Elevation < -4 ft

-4 to -2 ft

-2 to 0 ft

0 - 2 ft

2 - 4 ft

4 - 6 ft

Area with significant elevation change since city SWMM model was created

>6 ft

Drainage Impact Areas

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Watershed Boundary

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UMC

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CENTRAL BUSINES S DISTRICT

MIS SIS SIPPI RIVER

Existing Drainage System Base Flood Area

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MIS SIS SIPPI RIVER

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TUL ANE - GRAVIER

FRENCH QUARTER

TUL ANE - GRAVIER

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UMC

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TREME - L AFIT TE

CENTRAL BUSINES S DISTRICT

Elevation Drainage Line

< -4 ft

-4 to -2 ft

-2 to 0 ft

0 - 2 ft

2 - 4 ft

4 - 6 ft

Area with significant elevation change since city SWMM model was created

>6 ft

Tree Canopy and Urban Heat Impact Areas

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Existing Land Surface Temperatures Extreme Heat

High Heat

Severe Heat

Above Average Heat

CENTRAL BUSINES S DISTRICT

MIS SIS SIPPI RIVER

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Existing Tree Canopy and Vegetation

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UMC

MIS SIS SIPPI RIVER

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Design Scenarios

Work Across Scales R E C O N N E C T I N G THE GRID AND EXTENDING THE GREENWAY TO BASIN ST. R E N O VAT E D C H A R I T Y O N T U L A N E AV E N U E

Heroes Tulane Ave.

Charity Redevelopment

Lafitte Blueway

Lafitte Greenway 8 E

Duncan Plaza

X T E N D E D

R E E N W A Y

Armstrong Park

DOWNTOWN CAMPUS LONG TERM VISION PLAN MASTER PLAN PROJECTS 1. Elks Place ground floor renovation 2. Elks Place campus green 3. Cleveland St Streetscape 4. Tulane Ave Streetscape 5. Canal St Streetscape 6. Poydras + Perdido space moves (to Murphy) 7. Tidewater renovation + plaza 8. New partnership research/ academic building 9. TUMC transition to clinical + research space 10. Deming renovation 11. New academic building 12. 1430 Tulane renovation

Networks

BUILDING LANDSCAPE

7 12

INFRASTRUCTURE + PARKING

9 4

3 10

5 2

DDD Streets

Tulane Downtown Campus

Parcels GNOF

Legacy Park

Jung Hotel

Water-Neutral Development

Claiborne Avenue

Existing Conditions

Project Area: VA Hospital Site - Duncan Plaza

Charity Hospital VA Hospital Site NOPL Main Branch Heal Garage

Duncan Plaza

City Hall

architecture + planning + interiors

1119 Tchoupitoulas Street New Orleans LA 70130 Street 1119 Tchoupitoulas New Orleans 504.593.9074 tel LA 70130 504.593.9074 tel

studiowta.com

architecture + planning + interiors

architecture + planning + interiors 1119 Tchoupitoulas Street New Orleans LA 70130 1119 Tchoupitoulas Street New Orleans LA 70130 504.593.9074 tel 504.593.9074 tel

ST RE E

OGT AREM ST E REST ETRE

E ST R

significance highUhistoric E

no historic significance or high historic significance architectural merit

no historic significanc architectural merit

SA RA T

high potential for reuse due to scale high potential for reus highest historic significance and/or architectural character and/or architectural c

highest historic significance

H LIB ERTY S

H LIB ERT

PL A

PL AC E

EET

1937

SOUT

DID

TRE

DID

POERS DTIR DE OEST TRE

VENU

OUAMP

TSH R

TH R SOU

SOU

AMP

LOYO

ART

LA A

STRE

VENU

LA A

1950s-1980s

PER

VENU

T TREE

LLE S

LASA

TREE T LLE S

LASA

DID

PER

LOYO

1950s-1980s

LOYO

1948

LA A

E 1950s-1980s

1938

PER

VENU

1948

1938

1937

1961

STRE

SOUT

1937 1929 1937

LA A

1938

EL K

Y STR

1937

significant additionpreviously to significant, not enough previously significant, not enough historic structure historic material remaining of merit historic material remaining of merit

historic material remaining, historic material remaining, showing demarcation of original showing demarcation of original architectural merit questionable architectural merit building questionable footprint vs. additions building for footprint vs. additions for historically significant structures historically significant structures

1961 1938 1938 1948

significant addition to 1937 historic structure 1929

LOYO

1961 1938 1961

architectural merit questionable architectural merit building questionable footprint vs. additions building for footprint vs. a detrimental encroachement ondetrimental encroachement on historically significant historically significant historically significant structure historically significantstructures structure historically significant

historically significant

H LIB ERTY

1929

1938

1929

1949-51?1937

historic structure historic material remaining of merit historic material rema

no historic significance or no historic significance or high historic significance architectural merit architectural merit historic material remaining, historic material remaining, showing demarcation of original showing demarcation

SOUT

historic structure

high historic significance

H LIB ERT

IER

Y STR

GR1937 AV IER

high potential for reuse due to scale high potential for reuse due to scale highest historic significance historic significanthighest addition to significance previously toand/or architectural significant,character not enough previously significant, and/orsignificant architecturaladdition character

SOUT

1980s

LASA architecture + planning + interiors

KEY: IDENTIFICATION KEY: IDENTIFICATION OF SIGNIFICANCE OF SIGNIFICAN

LLE S FRETRREE ET ST TREE

IER

1980s

LASA

TRE

LLE S FRETRREE ET ST TREE T

RERE STRE ET S. TRO ST BR EE RETTSO N ST REE

IER

1937 1937

FRER SE. TRO ST BR EE RETTSO N F

TRE

1949-52

1980s

1949-51?

TRE

MOLIA S S. RO SON S AGNOTLRIEAET BERT TREET STRE SON ET STRE ET

1949-52

1937

BERT

1980s

1949-51?

MAG

TRE

1949-52

S. RO

detrimental encroachement ondetrimental encroach KEY: IDENTIFICATION KEY: IDENTIFICATION OF SIGNIFICANCE OF SIGNIFICANCE historically significant historically significant historically significant structurehistorically significant

1949-52

MAGMAG CLA CLA NOLI NOL RA S RA S A ST IA S TREE TRE REETTRE T ET ET

EA VE N

BO RN

REET

A ST

CLAR

1938

CL AI

REET

A ST

CLAR YD

VE NU E

AI BO

VE NU E

BO RN

1938

CL AI

EA VE N

1938

AI BO

The Old VA Site Re-Use Study, executed by Studio WTA and Spackman Mossop Michaels, identified the historic significance of each building or addition within the hospital site. The most significant buildings were recommended for preservation or rehabilitation. Most significant is the Charity Hospital School of Nursing (1) at Claiborne Avenue, portions of the power plant and utility buildings (2) at Freret and Lasalle Streets, and the heart of the VA Hospital (3).

OLD VA SITE RE-USE OLDSTUDY VA SITE New RE-USE Orleans, STUDY LA 70112 New Orleans, LA 70112

TREE

DDD VA Complex Study, 2017

S. S.DE RBIG NY S TRE

S.DE RBIG NY S TRE

Historic Significance

TR EM E

EET

OLD VA SITE RE-USE OLDSTUDY VA SITE New RE-USE Orleans, STUDY LA 70112 New Orleans, LA 70112

TRE

Historic Significance DiagramHistoric May 2017 Significance Dia

Historic Significance DiagramHistoric May 2017 Significance Diagram May 2017

studiowta.com

Source: Downtown Development District, Studio WTA, Spackman Mossop Michaels (SMM)

Buildings Proposed for Demolition Several buildings around the VA campus have no historic significance or are detrimental encroachments on their historic neighbors. The City of New Orleans will potentially use a portion of these buildings for office space and Civil District Courts. For the MIN Scenario, we envision demolishing the most detrimental structures to create open space. The MID Scenario follows the recommendations of the DDD VA study, while the MAX Scenario aligns with the HRI Charity District vision.

Gr av

i rd Pe

lle

ier

MIN Scenario Demolition

MID Scenario Demolition

MAX Scenario Demolition

Duncan Plaza

Source: Google Earth

HRI Charity District Vision The HRI Charity District vision proposed the most additional greenspace and extensive building demolition. The Charity School of Nursing building, and the Power building are left intact and the rest of the VA Site is turned into an extension of Duncan Plaza. This proposal is the starting point for MAX Scenario.

Source: HRI Properties

2017 Master Plan

To Lafitte Greenway & Armstrong Park

AV E E

STRE

NOPL

SHOPPING VILLAGE EVENT STAGE

PARKING OUTDOOR DINNING

SHARED STREETS

DUNCAN PLAZA

ET STRE

DID

TRE

LASA LLE

ET S

TREE

BERT

FRER

PER

SPORTS COURTS

SON

STRE

OLIA MAGN

AVEN

ROOF DECKS

LOYO LA

EET A STR

LAWN DOG PARK L

AV E

STRE E

DROP-OFF

ERTY

AVI E

PATIO

H LIB

RESIDENTIAL APARTMENTS

SOUT

AI BO RN

CHARITY FORUM

SERVICE DRIVE

S. RO

The Proposed design scenario incorporates elements from this conceptual design.

QUAD

CLAR

A great lawn is the green heart of the new development, with pedestrian connections to Poydras, Claiborne and Loyola, The Heal Garage would be opened up at the ground floor, creating covered outdoor space and increased connectivity between Duncan Plaza and the new developments on the VA Site. An allee of trees along Perdido Street provides a shaded pedestrian corridor from Loyola to Claiborne.

The 2017 Master Plan recommends preserving or rehabilitating the historic School of Nursing and VA Hospital, converting them into residential apartments. The historic utility buildings would become a commercial shopping and restaurant center.

NU E

DDD VA Complex Study

ORLEANS, LA VA ComplexCityNEW Hall

To Champions Square

Source: DDD, Studio WTA, SMM

Duncan Plaza Master Plan 2018

DO W

O ET W PLAN TREE ANALYSIS | MASTER N

E STRE LASALL

E STRE

LASALL

12” OAK

KE SI D

LEGEND PARKING GARAGE

This ambitious redesign of Duncan Plaza by OJB Landscape Architecture was commissioned by the Downtown Development District. LEGEND It preserves the largest, oldest oak trees and creates FLEXIBLE LAWN various program areas. Decorative CHILDREN’S PLAY and interactive water features CULTURAL PLAZA were proposed, but stormwater F&B PLAZA management of a scale that would DOG PARK reduce flood risk was not included in theGATHERING-READING-GAMES design.

12” OAK

EXISTING TREE

27” OAK

PARKING GARAGE

POTENTIAL RELOCATED TREE TREE TO BE REMOVED 36” OAK

FUTURE DEVELOPMENT

F&B PLAZA

27” OAK

REMOVE (3) PALM TREES

PERFORMANCE PLAZA

RAIN GARDENS

GATHERING-READINGGAMES TERRACE

27” OAK

CITY HALL

RAIN GARDEN

TREE TO BE REMOVED

24” OAK 24” OAK

6” OAK

36” OAK

LIBRARY

30” OAK 24” OAK

(4) 10” OAK 24” OAK

36” OAK 24” OAK

24” OAK REMOVE PALM TREE

36” OAK

PARKING GARAGE

10” OAK

24” OAK 24” OAK 15” OAK 30” OAK 54” OAK

REMOVE (4) PALM TREES

36” OAK

12” OAK REMOVE (2) PALM TREE

SI VE R

27” OAK

10” OAK

24” OAK

42” OAK

12” OAK

LIBRA

8” OAK

24” OAK

36” OAK

12” OAK

REMOVE (6) BALD CYPRESS TREES 30” OAK

REMOVE PALM TREE

12” OAK

REMOVE PALM TREE

30” OAK

24” OAK

DOG PARK

ET E STRE LASALL E AVENU LOYOLA

LEGEND EXISTING TREE

30” OAK

24” OAK

TREE ANALYSIS | MASTER PLAN

POTENTIAL RELOCATED TREE

PERFORMANCE PLAZA

GATHERING-READINGGAMES TERRACE CAFE/ RESTROOMS

CITY HALL

FLEXIBLE LAWN

CULTURAL PLAZA

Right: Tree survey performed by OJB identified the significant trees in Duncan Plaza to be protected, relocated, or removed.

REMOVE (3) PALM TREES

CHILDREN’S PLAY

PERDIDO STREET

STRUCTURES

REMOVE (3) PALM TREES

REMOVE (5) CREPE MYRTLE TREES

CAFE/ RESTROOMS

WATER

21” OAK

34” OAK

FLEXIBLE TERRACES DINING TERRACE

REMOVE (5) HACKBERRY TREES

27” OAK

GRAVIER STREET

FLEXIBLE TERRACE

WATER

ENUE

AV LOYOLA

TO W

N OAK 36” 27” OAK

REMOVE (3) PALM TREES

Source: Downtown Development District, OJB Landscape Architecture

Infrastructure Improvements

Large Scale Storage in Streets and Open Spaces The concept of Interceptor Streets - large scale water storage underneath existing roadways - is based on a previous study completed for the DDD and City of New Orleans Department of Public Works (DPW). Interceptor Streets include pervious pavement parking lanes and upgrades to drainage pipes. This study guided the current work, but was not included in the scope and thus was not modeled. Duncan Plaza and other open spaces (shown in green) also have potential to create significant additional water storage. Upgrades to pipe storage: 1.15M gallons or 1.97 acre feet Pervious pavement parking lanes on 45 blocks: 1.85M gallons or 5.68 acre feet Duncan Plaza underground storage: 3.91M gallons or 11.99 acre feet Total potential storage: 6.91M gallons or 21.22 acre-feet Duncan Plaza is a major opportunity, providing more storage than pipe upgrades and pervious pavement combined.

Design Scenario Storage Volume Duncan Plaza:

12 Ac Ft

Pervious Pavement: Increased Storage: Current Storage:

5.7 Ac Ft 2 Ac Ft 1.6 Ac Ft

Duncan Plaza

Potential Interceptor Streets

DDD Proposed Interceptor Street

Improved Drainage, Permeable Parking Lane, Subsurface Storage

Permeable Concrete Parking Lane at S. Galvez

Permeable Asphalt or Concrete

Gravel Storage Larger Infiltrating Drainage Pipes Alternate: Pave Drain Modular Permeable Pavers

DDD Living With WaterÂŽ Alternative Improved Storage, Ecological, and Spatial Quality

Improved Crosswalks

Bioretention Bump Out

Bioretention Plantings, Seattle

Pave Drain

Gravel Storage Infiltrating Pipe Structural Sidewalks Provide Space for Tree Roots and Water Storage

Existing Conditions

Project Area: Lafitte Greenway - Armstrong Park

Bayou St. John

DPS #2

Sojourner Truth Neighborhood Center Treme Commnity Center Lafitte Greenway Mahalia Jackson Theater

Armstrong Park

Municipal Auditorium

Congo Square

Basin Street Station

Carondelet Canal Turning Basin Past + Present

Circulating System

Greater New Orleans Urban Water Plan

Water source for future circulating water system

Credit: H + N + S, Waggonner & Ball

Lafitte Greenway + Armstrong Park RECONNECTING THE GRID

MUNICIPAL AUDITORIUM

Source: Lafitte Blueway, Waggonner & Ball

Source: Center City Transformation, HRI Properties

Eliminate Interstate Geometry of Basin St. Curve Achieve Prominent Exposure for Municipal Auditorium. Allow Greenway Trail Head to Basin St.

Right of Way Green Infrastructure Green Infrastructure Precedents

Green Street Program Portland Green Streets Program Rego Park New York Calabasas California RRM Design Group

Credit: Dana Brown & Associates

Paso Robles California SvR Best Practices Urban Bioswale

Sustainable Urban Drainage System Llanelli Wales Best Practices Porous Parking

Credit: Dana Brown & Associates

Subsurface Water Detention Typical -> Intensive

Modular Storage Units Precast Storage Vaults

Plastic Storage Vaults

Park Above Cisterns Kasukabe, Japan

Large, Underground Concrete Cisterns Kasukabe, Japan

Water Plazas Safety + Amenity

Credit: Waggonner & Ball

Tanner Springs Park Portland CMS

Redfern Park Sydney, Australia

Engehave Park, Copenhagen Tredje Natur

Stormwater Modeling Impact Areas

• Stormwater modeling included DPS Watersheds 2 & 3 • Design storm is the 10 year, 24 hour event (8.5 Inches of Rain) • Modeling ran over 25 scenarios and alternates • Initially, the model ran the Min, Mid and Max Scenarios for each project area, and then refined and combined them to achieve optimal results

Scenario 1 2 3 4 5 6 7 8 8.1 8.5 9 9.3 10 11 12.1 13

Storage to Combined Impact Area Storage Reduction Reduction Flood Acres Ratio Ac Ft Ac Ft Scenario Description Ac Ft Base 10 Year 24 Hour Flood 137.6 2.2 : 1 MIN Downtown 23.9 9.3 126.8 10.8 -8% MID Downtown 51.9 23.2 3.6 : 1 123.0 14.6 -11% MAX Downtown 65.9 26.5 4.3 : 1 122.2 15.4 -11% 2.8 : 1 MIN Lafitte 20.6 6.9 130.3 7.3 -5% MID Lafitte 40.4 28.7 2.4 : 1 120.6 17.0 -12% 30.1 118.0 19.6 -14% 3.7 : 1 MID Downtown + MIN Lafitte 72.5 MAX Downtown + MID Lafitte 110.4 47.7 3.8 : 1 108.2 29.4 -21% Infinite Storage Test 82.2 55.4 -40% MAX Downtown (upsized pipes 4 without Lafayette Square ) + MID Lafitte 110.4 47.7 2.7 : 1 97.0 40.6 -30% MAX Downtown + MAX Lafitte (routing from St Louis Culvert) 174.5 78.8 4.1 : 1 94.6 43.0 -31% 78.8 2.9 : 1 77.8 59.8 -43% MAX Downtown + MAX Lafitte (routing from Orleans Ave Culvert 1 + Upsized Pipes) 174.5 MAX Downtown (without Lafayette Square) + MAX Lafitte (routing from St Louis Culvert) 167.1 97.4 40.2 -29% 76.7 4.2 : 1 MAX Lafitte (routing from Orleans Ave Culvert) 108.6 52.2 2.9 : 1 99.9 37.7 -27% Proposed Scenario: MID Downtown (upsized pipes 2) + MAX Lafitte (routing from Orleans Ave Culvert 160.4 75.5 3.0 : 1 84.4 53.2 -39% "Minimum" MIN Downtown + MIN Lafitte 44.6 16.2 2.6 : 1 120.7 16.9 -12%

Downtown Impact Area Flood Reduction Ac Ft Ac Ft 56.3 45.9 42.1 41.3 50.7 48.8 38.6 36.9 13.6 26.1 25.2 20.2 28.0 39.4 26.1 42.9

10.4 14.2 15.0 5.6 7.5 17.7 19.4 42.7 30.2 31.1 36.1 28.3 16.9 30.2 13.4

-19% -25% -27% -10% -13% -31% -34% -76% -54% -55% -64% -50% -30% -54% -24%

Lafitte Impact Area Flood Reduction Ac Ft Ac Ft 123.6 114.2 111.4 110.6 116.8 107.2 106.9 97.3 79.4 89.6 86.4 72.0 87.2 87.0 75.7 108.4

9.3 12.1 13.0 6.8 16.4 16.7 26.3 44.2 34.0 37.2 51.6 36.4 36.5 47.9 15.2

-8% -10% -10% -6% -13% -14% -21% -36% -28% -30% -42% -29% -30% -39% -12%

Stormwater Modeling VA Hospital Site - Duncan Plaza

Credit: Procella

Urban Water Design Components Basis of Stormwater Calculations and Estimates Type

Average Depth/SF

Type

Average Depth/SF

New Development

0.1 to 2 ft

Residual Space

3 ft

New buildings and sites store code minimum 1.25 inches More intensive storage at City Hall redevelopment sites

Pavement Storage

Structural water storage under parking, sidewalks and plazas.

Open Space Planted bioswales, open canals, and/or structural water storage under lawns and fields

Interventions in courtyards, setbacks and open space between VA buildings Flow through planters, cisterns, subsurface storage, bioretention

1.5 ft

AllĂŠe of Trees

Trees planted in structural soil with pervous paving or in bioswales

3 ft

Green/Blue Roof

Landscaping or detention on rooftops

1.5 ft

MIN Scenario

Duncan Plaza + VA Site + City Hall The Minimum (MIN) Scenario accounts for the Cityâ&#x20AC;&#x2122;s use of some of the VA buildings, while creating new urban park spaces through selective demolition. The City owns a portion of the Duncan Plaza site; interventions are limited to parcels controlled by the City. The pavilion, mounds and trees are preserved; the remainder of the park would be designed with stormwater management features. Jung Hotel

LSUHSC

Tulane Medical Center Hospital

Former Charity Hospital VA Site

NOPL

Design Scenario Impact Area Storage Volume Flood Volume

56 Ac Ft Base 46 Ac Ft MIN Scenario (19%) Total 23.9 Ac Ft Pavement Duncan Plaza

4.1 Ac Ft 4.7 Ac Ft

Open Space 15.2 Ac Ft

Duncan Plaza

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development

City Hall

Node Flood Depth 2 ft 1 ft 0 ft

Existing Flood Depth Scenario Flood Depth

Superdome

MID Scenario

Duncan Plaza + VA Site + City Hall The Middle (MID) Scenario uses the DDD VA Site and Duncan Plaza studies as a starting point. Additional detention around City Hall and the New Orleans Public Library is added. This Scenario also includes more extensive building demolition and site redevelopment.

Jung Hotel

LSUHSC

Tulane Medical Center Hospital

Former Charity Hospital VA Site

NOPL

Design Scenario Impact Area Storage Volume Flood Volume

Total 51.9 Ac Ft Green Roof

0.4 Ac Ft

New Development

4 Ac Ft

Pavement 11.6 Ac Ft Duncan Plaza

12 Ac Ft

Open Space 23.8 Ac Ft

56 Ac Ft Base 42 Ac Ft MID Scenario (25%)

Duncan Plaza

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development

City Hall

Node Flood Depth 2 ft 1 ft 0 ft

Existing Flood Depth Scenario Flood Depth

Superdome

MAX Scenario

Duncan Plaza + VA Site + City Hall The Maximum (MAX) Scenario uses the HRI Properties Charity District, DDD VA Site and Duncan Plaza studies as a starting point. Stormwater detention added in the MID Scenario is added to the MAX as well. Stormwater detention at Lafayette Square has been added as well, shown in the inset map. This scenario creates marginally more storage and flood reduction with significantly more building demolition. Jung Hotel

LSUHSC

Tulane Medical Center Hospital

Former Charity Hospital VA Site

NOPL

Design Scenario Impact Area Storage Volume Flood Volume Total 58.6 Ac Ft Green Roof

0.4 Ac Ft

New Development Pavement

4 Ac Ft 8.7 Ac Ft

Duncan Plaza

12 Ac Ft

Open Space 39.5 Ac Ft

56 Ac Ft Base 41 Ac Ft MAX Scenario (27%)

Duncan Plaza

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development

City Hall

Node Flood Depth 2 ft 1 ft 0 ft

Existing Flood Depth Scenario Flood Depth

Superdome

Lafayette Square

MIN Scenario

Lafitte Greenway + Armstrong Park The Minimum (MIN) Scenario shows storage opportunities within the former Carondelet Canal right of way in the Lafitte Greenway and through manipulating existing water levels in Armstrong Park.

Design Scenario Impact Area Storage Volume Flood Volume

ist

124 Ac Ft Base 117 Ac Ft MIN Scenario (6%)

ing

fitt eG

re e

nw ay

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development

Total 20.6 Ac Ft

Mahalia Jackson Theater

Node Flood Depth 2 ft

Open Water

7.5 Ac Ft

1 ft

Open Space

13.1 Ac Ft

0 ft

Existing Flood Depth Scenario Flood Depth

Tr ail

SWB Sewer Station Municipal Auditorium Congo Square

MID Scenario

Lafitte Greenway + Armstrong Park The Middle (MID) Scenario uses the WBAE Lafitte Blueway and HRI Properties City Center Transformation studies as a starting point. This scenario includes the redevelopment of nearby sites, and works around the redesign of Basin Street.

Mahalia Jackson Theater

Design Scenario Impact Area Storage Volume Flood Volume 124 Ac Ft Base

SWB Sewer Station

107 Ac Ft MID Scenario (13%)

Municipal Auditorium

Total 40.4 Ac Ft New Development Pavement Open Water

4 Ac Ft 8.7 Ac Ft 7.5 Ac Ft

Open Space 26.9 Ac Ft

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development Node Flood Depth 2 ft 1 ft 0 ft

Existing Flood Depth Scenario Flood Depth

Congo Square

MAX Scenario

Lafitte Greenway + Armstrong Park The Maximum (MAX) Scenario uses the WBAE Lafitte Blueway and HRI Properties City Center Transformation studies as a starting point. This scenario includes the full extent of the Lafitte Greenway, as shown in the inset. The MAX scenario proposes significantly more storage volume and creates the most flood reduction in the Lafitte impact area.

Full Extent

Window

Mahalia Jackson Theater

Design Scenario Impact Area Storage Volume Flood Volume Total 108.6 Ac Ft New Development Pavement Open Water

124 Ac Ft Base

SWB Sewer Station

4 Ac Ft 8.7 Ac Ft 7.5 Ac Ft

Municipal Auditorium

87 Ac Ft MAX Scenario (30%)

Open Space 95.1 Ac Ft

Storage Type Open Space Residual Space Allee Blue/Green Roof Open Water Pavement New Development Node Flood Depth 2 ft 1 ft 0 ft

Existing Flood Depth Scenario Flood Depth

Congo Square

Matrix of Design Scenarios MIN

MID

MAX 1

MAX 2 Run 9.3 Lafitte Reduces Flooding in Treme - Lafitte

Lafitte

*Drawn at 1/3 the scale of downtown interventions

Base Flood Flood Reduction: 124 AcFt 6 AcFt (7%)

Run 9 Lafitte Reduces Floooding in Tulane - Gravier

Flood Reduction:

16 AcFt (13%)

37 AcFt (30%) HRI Masterplan

HRI Masterplan

Downtown

Tree Relocation based on OJB masterplan

Base Flood Flood Reduction: 56 AcFt 10 AcFt (19%) Combined Base Flood 124 AcFt

Lafayette Square

Flood Reduction:

14 AcFt (25%)

15 AcFt (27%)

Flood Reduction

Flood Reduction:

41 AcFt (30%)

43 AcFt (31%)

60 AcFt (43%)

Lafayette Square

Matrix of Design Scenarios Proposed

MINIMUM

MAX 2

PROPOSED Run 9.2 Lafitte Reduces Flooding in Treme - Lafitte

Lafitte

*Drawn at 1/3 the scale of downtown interventions

Base Flood Flood Reduction: 124 AcFt 6 AcFt (7%)

Flood Reduction:

37 AcFt (30%)

MID

Downtown

Tree Relocation based on OJB masterplan

Base Flood Flood Reduction: 56 AcFt

10 AcFt (19%)

Combined Base Flood Flood Reduction: 124 AcFt 17 AcFt (12%)

Flood Reduction:

14 AcFt (25%) Flood Reduction:

53 AcFt (39%)

DRAFT

Impact Areas and Base Flood Base Flood Volume: 138 Ac Ft

rt pa ui

ras S t

3 - 6by in combining 6 - 9 all in of the subcatchments > 12 in < 1 inImpact areas 1 - 3 in 9 - 12 in Project were created where the MAX Scenario reduced flooding or stress on the drainage network. Open Space Residual Space Pavement New Development Green Roof

e Av e rn

FRENCH QUARTER

Loyo

la A ve

eA ve

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

Flood ImpactDepth AreasReduction from 10-year, 24-hour Design Storm Baseline

lan

IBERVILLE

MIS SIS SIPPI RIVER

Poyd

MIS SIS SIPPI RIVER

la A ve Loyo

MA Down X s tow cen n ario

D IM OW PA N C TO T W A N RE A

lS t

FRENCH QUARTER

/I -1 0

Ga N

/I -1 0 e e

IBERVILLE

eA ve

TUL ANE - GRAVIER

lS t

lan

ce na rio

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

L IM AFI PA T T CT E AR

TREME - L AFIT TE

La fitt eM AX S

Drainage Pump Station 2

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth 0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Area with significant elevation change since city SWMM model was created Major Drainage Line Credit: Waggonner & Ball

Infinite Storage Test Base Flood Volume: 138 Ac Ft

Infinite Storage Test Flood Reduction: 55 Ac Ft (-40%) reduces flooding in Downtown and has a significant impact in the Treme - Lafitte Neighborhood as well. However local topographic depressions such as the area around the Jung Hotel and along Gravier St remain partially flooded. This test demonstrates that even an infinite amount of stormwater detention around Duncan Plaza cannot solve all of Downtown’s flooding issues.

This scenario tested what would happen if all of the stormwater flowing through the culvert underneath Loyola Ave was removed from the drainage system near Duncan Plaza. This scenario would eliminate all of Duncan Plaza and City Hall’s stormwater as well as all of the CBD’s stormwater upstream of Duncan Plaza. This entirely unrealistic scenario dramatically

Drainage Pump Station 2 EA

3 - 6 in

9 - 12 in

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Minimum Scenario

Base Flood Volume: 138 Ac Ft

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Minimum Scenario Flood Reduction: 17 Ac Ft (-12%)

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Proposed Scenario: MID Downtown + MAX Lafitte Base Flood Volume: 138 Ac Ft

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Proposed Scenario Flood Reduction: 53 Ac Ft (-39%)

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Maximum Scenario: Lafitte Routes to Orleans Culvert Base Flood Volume: 138 Ac Ft

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Maximum Scenario Flood Reduction: 60 Ac Ft (-43%)

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Maximum Scenario: Lafitte Routes to St. Louis Culvert Base Flood Volume: 138 Ac Ft Or

Maximum Scenario Flood Reduction: 43 Ac Ft (-31%) Or

TREME - L AFIT TE

L IM AFI PA T T CT E AR

3 - 6 in

9 - 12 in

Area with significant elevation change since city SWMM model was created

rt pa m Ra /I -1 0 e Av e

Loyo

la A ve

eA ve

FRENCH QUARTER

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

TUL ANE - GRAVIER

MIS SIS SIPPI RIVER

la A ve Loyo

Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

D IM OW PA N C TO T W A N RE A

< 1 in

lv e

/I -1

eA ve

FRENCH QUARTER

lan

lS t

lv Ga

TUL ANE - GRAVIER

EA St

L IM AFI PA T T CT E AR

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in

0 - 3 in Open Space

3 - 6 in

6 - 9 in Residual Space

9 - 12 in Pavement

12 - 15 in

15 - 18 in New Development

18 - 24 in

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 30% 1. La Salle at Cleveland Or

L IM AFI PA T T CT E AR

TREME - L AFIT TE

m Ra

e Av

IBERVILLE

lle

MIS SIS SIPPI RIVER

1 ev

FRENCH QUARTER

eA ve

lan

Loyo

la A ve

The modeled existing conditions showed 16.9 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 7% and the proposed scenario is expected to reduce flooding by 30%. While flooding is not eliminated at this location, reduction in flood depth may prevent building flooding and allow emergency vehicle access.

lS t

TUL ANE - GRAVIER

This intersection, at the rear of the Jung Hotel on Canal Street, frequently floods. The hotel has constructed floodwalls with barriers in order to protect the building.

/I -1 0

Credit: Google

Conclusion: The Lafitte Greenway-Armstrong Park project area routed to the Orleans Avenue culvert showed the most dramatic decrease in flooding at this location.

Drainage Pump Station 2

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 51% 2. S. Claiborne at Poydras Or

L IM AFI PA T T CT E AR

TREME - L AFIT TE

m Ra

e Av

lS t

FRENCH QUARTER

MIS SIS SIPPI RIVER

eA ve

lan

IBERVILLE

TUL ANE - GRAVIER

This intersection leads to the on-ramps for Interstate 10, serving as a major traffic connector from the Central Business District to the metro area. Existing flooding here is significant, which impacts safety and transportation.

/I -1 0

Credit: Google

Poy

dra

Loyo

la A ve

The modeled existing conditions showed 13.9 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 31% and the proposed scenario is expected to reduce flooding by 51%. These are considered major improvements to the flooding in the area. Conclusion: The VA Hospital Site-Duncan Plaza project area with upsized pipes in Perdido St. and S. Galvez St. have the biggest impact on this intersection.

Drainage Pump Station 2

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 50% 3. S. Galvez at Perdido Or

L IM AFI PA T T CT E AR

TREME - L AFIT TE

m Ra

e Av

FRENCH QUARTER

MIS SIS SIPPI RIVER

eA ve

lan

IBERVILLE

Loyo

la A ve

The modeled existing conditions showed 16.2 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 21% and the proposed scenario reduces flooding by 50%. These are considered major improvements to the flooding in the area.

lS t

TUL ANE - GRAVIER

This intersection is at the edge of the LSU Health Science Center (HSC) Campus, a major regional health care and educational complex. Existing flooding here is significant, impacting traffic for emergency vehicles.

/I -1 0

Credit: Google

Conclusion: The VA Hospital Site-Duncan Plaza area interventions with upsized pipes in Perdido St. and S. Galvez St. produced the largest reduction of flooding in this area.

Drainage Pump Station 2

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 12% 4. S. Liberty at Girod Or

L IM AFI PA T T CT E AR

TREME - L AFIT TE

m Ra

e Av

FRENCH QUARTER

MIS SIS SIPPI RIVER

eA ve

lan

IBERVILLE

Loyo

la A ve

The modeled existing conditions showed 17.8 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 3% and the proposed scenario is expected to reduce flooding by 12%.

lS t

TUL ANE - GRAVIER

This intersection is the primary entrance to the Superdome and Smoothie King Center, along with access to adjacent hotels and office buildings. Existing flooding is significant, disrupting traffic, economic activity, and public safety.

/I -1 0

Credit: Google

Conclusion: The VA Hospital Site-Duncan Plaza area interventions with upsized pipes in Perdido St. and S. Galvez St. , along with the interventions in Lafayette Square, produced the largest reduction of flooding in this area.

Drainage Pump Station 2

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 20% 5. N. Johnson at Bienville Or

L IM AFI PA T T CT E AR

TREME - L AFIT TE

m Ra St

e Av

FRENCH QUARTER

Loyo

Conclusion: The Lafitte Greenway-Armstrong Park project area routed to the Orleans Avenue culvert showed the most significant decrease in flooding at this location.

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

MIS SIS SIPPI RIVER

eA ve

lan

IBERVILLE

la A ve

The modeled existing conditions showed 10.4 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 5%, and the proposed scenario is expected to reduce flooding by 20%.

lS t

TUL ANE - GRAVIER

This intersection is located in between the UMC and Lafitte Greenway, and experiences significant flooding.

/I -1 0

Credit: Google

5 St Lo ui s

Drainage Pump Station 2

Impacts at Specific Sites

Proposed Scenario Flood Depth Reduction: 38% 6. Basin at N. Claiborne le

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2

EA St

pa m Ra

e Av

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline < 1 in Open Space

1 - 3 in

3 - 6 in

Residual Space

6 - 9 in Pavement

9 - 12 in New Development

> 12 in Green Roof

MIS SIS SIPPI RIVER

eA ve

lan

IBERVILLE

la A ve

The modeled existing conditions showed 8.3 inches of flooding at this location in a 10-year 24-hour design storm event. The minimum scenario is expected to reduce flooding by 7% and the proposed scenario is expected to reduce flooding by 38%.

lS t

TUL ANE - GRAVIER

This intersection leads to an on-ramp for Interstate 10, serving as a major traffic connector from the edge of the Central Business District and French Quarter to the metro area. Existing flooding impacts safety and transportation.

/I -1 0

Credit: Google

Conclusion: The Lafitte Greenway-Armstrong Park project interventions, specifically in the area closest to this intersection, caused the greatest impact for flood reduction.

ding AcFt

Flooding AcFt

140 Summary

140

Impact120 Areas

120

100

1. Model shows that water storage benefits correlate more with 80 topography rather than with pipe connections in the drainage system

80 60

2. Additional water storage should be located in higher elevation areas 40 to reduce downstream flooding

40 20

3. Small change in benefit from MID to MAX scenarios in the CBD area 0

TREME - L AFIT TE

e Av e rn bo

rt pa

IBERVILLE

lS t

TUL ANE - GRAVIER

fitt e Co

FRENCH QUARTER

eA ve

ydr

la A ve

CENTRAL BUSINES S DISTRICT

Loyo

Area Base Area Flood Base Flood Scenario Minimum Scenario Proposed Scenario Minimum Proposed Scenario (Acres) Volume (Acres) (Ac Ft)Volume (Ac Ft) (Ac Ft) Reduction Reduction (Ac Ft) Reduction (Ac Ft) Reduction (Ac Ft) 137.616.9 (-12%) 16.9 (-12%) 137.6 53.2 (-39%) 53.2 (-39%) d Impact Combined Area Impact Area 293.7 293.7 123.615.2 (-12%) 15.2 (-12%) 123.6 47.9 (-39%) 47.9 (-39%) 254.1 254.1 mpact Area Lafitte Impact Area 56.313.4 (-24%) 13.4 (-24%) 56.3 30.2 (-54%) 30.2 (-54%) 154.1 154.1 wn Impact Downtown Area Impact Area afitte Treme Lafitte 113.6 3.3 (-5%)19.8 (-28%) 19.8 (-28%) 71.83.3 (-5%) 71.8 113.6 32.85.9 (-18%) 5.9 (-18%) 32.8 15.4 (-47%) 15.4 (-47%) Business Central District Business88.6 District 88.6 22.0 7.3 (-33%) 7.3 (-33%) 22.0 ravier Tulane Gravier 60.6 60.6 14.3 (-65%) 14.3 (-65%) D OWNTOWN 8.9 0.1 (-1%) 8.9 24.1 t John Bayou St John 24.1 0.1 (-1%) 3.3 (-37%) 3.3 (-37%)IMPACT AREA 1.20.0 (-1%) 1.2 0.0 (-1%)0.0 (-3%) 0.0 (-3%) 3.3 uarterFrench Quarter 3.3 2.7 2.7 0.70.2 (-24%) 0.2 (-24%) Iberville 0.7 0.4 (-61%) 0.4 (-61%)

lan

MIS SIS SIPPI RIVER

L AFIT TE IMPACT AREA

Im pa Do bin c w ed nt Im t A re ow p n act a La Im fitt pa Are c a e Im t A Do Tr pa rea em ct Ce wn nt tow e - Are ra n L a l B Im afi tte us p a in c es t A s re Di a Tr s e Ce Tu me tric nt ra lan - La t lB e fi us - G tte r in es avi Ba s D er is y Tu ou tric la St t ne Jo Fr - G hn en ch rav i Ba Qu er yo art u e St r J Lo F Ib ohn w re e er nc rvi lle Ga h Q rd u en ar Di ter st ri Lo Ib ct w er er vi lle Ga rd en Di st ric t

4. Heroic scale water storage projects are needed to reduce flooding

/I -1 0

BAYOU ST JOHN

Flood Reduction from 10-year, 24-hour Design Storm Baseline Base Flooding

Minimum Scenario Flooding

Proposed Scenario Flooding

* Relatively insignificant volume of existing flooding compared to other neighborhoods in the Combined Impact Area

III Proposed Approach

Vision Priority areas: 1. Duncan Plaza and the VA Hospital Site 2. Armstrong Park and Lafitte Greenway

Extended study area

Duncan Plaza: Civic Space Sacred Place

Duncan Plaza has been the focal point and primary gathering place for the recent protest rallies, including Black Lives Matter. Given the recent and past history of this important civic space, careful study and sincere community engagement will be necessary for the redesign of the park.

Minimum and Proposed Scenarios VA Hospital Site - Duncan Plaza

Minimum

Proposed

This scenario utilizes city owned land for stormwater management interventions. Subsurface storage under lawns and paving at Duncan Plaza respects oak tree canopies. Parking lot behind City Hall and parking lanes on Perdido, Gravier, LaSalle, and Freret streets reconstructed with subsurface storage and permeable paving. Select non-historic buildings at VA Site demolished to make space for urban water features.

Duncan Plaza rebuilt with a combination of subsurface storage, open basins, and water features. Perdido, Gravier, and LaSalle completely reconstructed with subsurface storage and permeable pavers. Non-historic structures around the VA demolished to make space for urban water features. An allee of trees along Perdido street, with subsurface detention, connect Duncan Plaza to the redeveloped VA Site. The Heal Garage and the New Orleans Public Library are ideal sites for demonstation green or blue roofs.

* Note: Scenarios are adaptable to alternative building preservation and demolition proposals

Section Diagram

VA Hospital Site - Duncan Plaza

VA Hospital Site

Charity Hospital

Heal Garage

New Development

Roof Garden Blue/Green Roof Stormwater Park

Permeable Paving

NOPL Main Branch

Rain Garden

Water Square

Detention Basin

Duncan Plaza

I-10

Subsurface Storage

Loyola Ave

Vision

VA Hospital Site - Duncan Plaza

New Development with Ambitious Storage

Roof Garden

Stormwater Park

Blue/Green Roof

Rain Garden Detention Basin

LEGEND Open Space Bioswale/Rain Garden Tree Water Path Plaza Permeable Paving Blue/Green Roof New Development New Building

Water Garden Permeable Paving

Subsurface Storage

Minimum and Proposed Scenarios Lafitte Greenway - Armstrong Park

Minimum

This scenario utilizes city owned land for stormwater management interventions in the Lafitte Greenway and Armstrong Park. A new civic space, located in the right-of-way of the former Carondolet Canal, is excavated to create an urban waterway.

Proposed

The right-of-way of the historic Carondelet excavated to create an urban waterway connected to Bayou St. John. Surface and subsurface detention under the the Lafitte Greenway and at the site of the historic turning basin relieves the St. Louis drainage canal. Development sites along the Lafitte Greenway and Armstrong Park should be incentivized to provide more stormwater detention than required by code.

Lafitte Greenway + Armstrong Park

Source: Lafitte Blueway,Waggonner & Ball

Lafitte Blueway

Greater New Orleans Urban Water Plan

source: Bosch Slabbers

Lafitte Blueway New Turning Basin

New Development

New Development Blue/Green Roof

St. Louis Street

New Street Rain Garden

Permeable Paving

Reconfigured Basin Street Bike Path

Water Square

Existing Culvert

Hydraulic Pressure

Subsurface Storage

Detention Basin

Vision

Lafitte Greenway - Armstrong Park

Soft & Hard Edges

Accessible Water

Water Square

Improved Canal

Stormwater Wetlands LEGEND Open Space Bioswale/Rain Garden Tree Water Path Plaza Permeable Paving Blue/Green Roof New Development New Building

Subsurface Storage

Bioswales New Development with Ambitious Storage

Phasing

Proposed Scenario

Downtown

Lafitte Lon g Te rm Nea Term r

Ne ar Te rm

Lo ng Te rm

Point of Contact Ella Delio Greater New Orleans Foundation ella@gnof.org 617.230.6877 Ramiro Diaz Waggonner & Ball ramiro@wbae.com 504.524.5408

Appendix

Preliminary Cost Estimate

Preliminary Cost Estimate Summary ID

Type

Site

Sq Ft

Acres

Water Depth (ft)

StorageAcFt ACRE/FT to CF CF/CY COST COST COST COST COST COST COST COST COST Bed Planting Irrigation Tree Allee Sod Totals 43559.90 27.00 Excavavtion/CY Contaminated SoRaintanks/CF Weir Control Structure Permeable Pavers -Vehicular Green Roof Assembly BioSwale Soils/CY $50.00 $40.00 $20.00 $5,000.00 $20.00 $35.00 $75.00 $6.00 $1.25 $825.00 $1.00 0.1 0.09 3967.52 146.95 $9,184.07 $1,469.45 $2,938.90 $5,000.00 $793,505.61 0.1 0.25 10819.65 400.73 $25,045.49 $4,007.28 $8,014.56 $5,000.00 $2,163,935.69 0.1 0.06 2661.85 98.59 $6,161.70 $985.87 $1,971.74 $5,000.00 $532,372.14 3 0.36 15475.44 716.46 $44,778.49 $7,164.56 $42,987.35 $30,950.96 $6,448.12 0.1 0.05 2275.46 84.28 $5,267.27 $842.76 $1,685.53 $5,000.00 $455,092.92 3 0.22 9496.43 439.65 $27,478.09 $4,396.49 $26,378.97 $18,992.90 $3,956.85 0.1 0.13 5847.26 216.57 $13,535.33 $2,165.65 $4,331.31 $5,000.00 $1,169,455.16 3 1.37 59508.40 2755.02 $172,188.67 $27,550.19 $165,301.12 $119,017.08 $24,795.22 Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

• Pro-bono cost estimate performed by RCI

A 3.02 A 3.03 A 3.04 A 3.05 A 3.06 A 3.07 A 3.08 A 3.09

New Development New Development New Development Open Space New Development Open Space New Development Open Space

Armstrong Park Armstrong Park Armstrong Park Armstrong Park Armstrong Park Armstrong Park Armstrong Park Armstrong Park SF

39675.28 108196.78 26618.61 5158.49 22754.65 3165.48 58472.76 19836.18 283878.23

0.91 2.48 0.61 0.12 0.52 0.07 1.34 0.46

Description $812,098.04 Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $2,206,003.02Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $546,491.46 Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $132,329.47 Excavated bioswale with overflow to drainage system $467,888.48 Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $81,203.31 Excavated bioswale with overflow to drainage system $1,194,487.45Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $508,852.28 Excavated bioswale with overflow to drainage system $5,949,353.49 $297,467.67 $178,480.60 $297,467.67 $892,403.02 $7,615,172.47

• Quantity Takeoffs derived from GIS shapefile of the Proposed Design Scenario for the Duncan Plaza, VA, Lafitte, and Armstrong Park study areas Per SF

C 3.01 C 3.02 C 3.03 C 3.04 C 3.05 C 3.06 C 3.07 C 3.08

Pavement Open Space Open Space Open Space Open Space Pavement New Development New Development

City Hall City Hall City Hall City Hall City Hall City Hall City Hall City Hall SF

Per SF

26.83

32267.19 13078.96 25198.31 9112.18 8119.23 18411.74 41336.96 18593.14 166117.71

0.74 0.30 0.58 0.21 0.19 0.42 0.95 0.43

1.5 3 3 3 3 1.5 0.1 0.1

1.11 0.90 1.74 0.63 0.56 0.63 0.09 0.04

48400.67 39236.79 75594.75 27336.47 24357.63 27617.55 4133.69 1859.31

1792.62 1453.21 2799.81 1012.46 902.13 1022.87 153.10 68.86

$112,038.59 $90,825.90 $174,987.85 $63,278.87 $56,383.41 $63,929.50 $9,568.72 $4,303.96

$17,926.17 $14,532.14 $27,998.06 $10,124.62 $9,021.35 $10,228.72 $1,531.00 $688.63

$35,852.35

$5,000.00

$55,996.11

$5,000.00

$20,457.44 $3,061.99 $1,377.27

$5,000.00 $5,000.00 $5,000.00

$645,343.74

$108,991.08 $209,985.42 $75,934.64 $67,660.10

$184,117.39 $826,739.23 $371,862.84

$78,473.76 $151,189.85 $54,673.07 $48,715.38

$16,348.70 $31,497.89 $11,390.22 $10,149.04

Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

28.53

$816,160.85 Subsurface void/vault space for infiltration & detention (under parking lot) $309,171.58 Excavated bioswale with overflow to drainage system $656,655.18 Subsurface void/vault space for infiltration & detention (under paved plaza) $215,401.41 Excavated bioswale with overflow to drainage system $191,929.27 Excavated bioswale with overflow to drainage system $283,733.05 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $845,900.94 Demolish existing concrete parking structure; subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $383,232.70 Demolish existing City hall wing; subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $3,702,184.98 $185,109.25 $111,065.55 $185,109.25 $555,327.75 $4,738,796.78

• Estimates focused on stormwater management cost drivers, including excavation, subsurface storage, permeable paving, bioswales, open canals, basic plantings, irrigation, and outlet to drainage system

D 3.01 D 3.02 D 3.03 D 3.04 D 3.05 D 3.06

Open Space Open Space Pavement Pavement New Development Green Roof

Duncan Plaza Duncan Plaza Duncan Plaza Duncan Plaza Duncan Plaza Duncan Plaza SF

Per SF

L 3.01 L 3.02 L 3.03 L 3.04 L 3.05 L 3.06 L 3.07 L 3.08 L 3.09 L 3.10 L 3.11 L 3.12 L 3.13 L 3.14 L 3.15 L 3.16 L 3.17 L 3.18 L 3.19 L 3.20 L 3.21 L 3.22 L 3.23 L 3.24 L 3.25 LS 3.01 LS 3.02 LS 3.03 ADD

Open Space Open Space Open Space Open Space Open Space Pavement New Development Pavement New Development Pavement New Development Pavement New Development Pavement New Development Open Space Open Space Open Space Open Space Open Space Open Space Open Space Open Space Open Space Open Space Open Space Pavement Pavement Base 3' Cut

Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafitte Greenway Lafayette Square Lafayette Square Lafayette Square

109082.87 65158.50 35341.63 36983.23 27360.43 31226.35 305153.01

2.50 1.50 0.81 0.85 0.63 0.72

3 3 1.5 1.5 2 0.25

7.51 4.49 1.22 1.27 1.26 0.18

327247.85 195475.05 53012.32 55474.72 54720.74 7806.57

12120.29 7239.82 1963.42 2054.62 2026.69 0.00

$757,518.17 $452,488.55 $122,713.70 $128,413.70 $126,668.38

7.39 0.19 0.26 0.26 0.22 1.67 1.57 0.28 1.77 0.25 1.77 0.64 1.84 0.22 1.33 3.62 4.50 3.48 0.30 0.16 3.02 0.80 0.70 0.85 6.12 1.21 0.56 0.28

3 3 3 3 3 1.5 0.1 1.5 0.1 1.5 0.1 1.5 0.1 1.5 0.1 3 3 3 3 1.5 3 1.5 1.5 3 3 5 1.5 1.5

22.17 0.58 0.79 0.77 0.66 2.50 0.16 0.43 0.18 0.37 0.18 0.95 0.18 0.33 0.13 10.87 13.49 10.44 0.91 0.24 9.06 1.19 1.05 2.54 18.36 6.07 0.84 0.42

965627.26 25357.55 34472.45 33619.00 28817.47 108935.31 6854.31 18602.63 7719.67 16011.21 7713.61 41568.51 8011.57 14468.68 5796.82 473366.01 587458.87 454601.05 39654.26 10561.08 394783.95 52035.54 45633.11 110493.62 799958.25 264289.57 36783.20 18128.90

35763.97 939.17 1276.76 1245.15 1067.31 4034.64 253.86 688.99 285.91 593.01 285.69 1539.57 296.72 535.88 214.70 17532.07 21757.74 16837.08 1468.68 391.15 14621.63 1927.24 1690.12 4092.36 29628.08 9788.50 1362.34 671.44 219078.99

$2,235,248.29 $58,698.04 $79,797.35 $77,821.76 $66,707.11 $252,165.08 $15,866.45 $43,061.65 $17,869.60 $37,062.98 $17,855.59 $96,223.41 $18,545.29 $33,492.31 $13,418.57 $1,095,754.65 $1,359,858.49 $1,052,317.24 $91,792.27 $24,446.94 $913,851.73 $120,452.64 $105,632.21 $255,772.28 $1,851,755.20 $611,781.42 $85,146.29 $41,965.05 $6,846,218.46

$121,202.91 $72,398.17 $19,634.19 $20,546.19 $20,266.94

$242,405.82

$5,000.00

$39,268.38 $41,092.39 $40,533.88

$5,000.00 $5,000.00 $5,000.00

$353,416.26 $369,832.32 $547,208.66

$909,021.81 $542,986.26

$98,174.58 $390,951.00

$136,353.58 $81,448.13

$92,720.44

$1,092,922.17

Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

28.69

321876.49 8452.54 11490.84 11206.36 9605.85 72623.71 68543.22 12401.78 77196.87 10674.16 77136.32 27712.41 80115.85 9645.81 57968.36 157789.03 195820.07 151534.03 13218.12 7040.74 131594.95 34690.44 30422.15 36831.29 266653.36 52858.04 24522.19 12085.96 1971710.92 1971710.92

$357,639.73 $9,391.69 $12,767.58 $12,451.48 $10,673.14 $40,346.41 $2,538.63 $6,889.86 $2,859.14 $5,930.08 $2,856.89 $15,395.75 $2,967.25 $5,358.77 $2,146.97 $175,320.74 $217,577.36 $168,370.76 $14,686.76 $3,911.51 $146,216.28 $19,272.42 $16,901.15 $40,923.56 $296,280.83 $97,885.03 $13,623.41 $6,714.41 $2,190,789.91

$715,279.45

$5,000.00

$80,692.82 $5,077.26 $13,779.73 $5,718.27 $11,860.15 $5,713.79 $30,791.49 $5,934.49 $10,717.54 $4,293.94 $350,641.49 $435,154.72 $336,741.52

$5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00

$292,432.55 $38,544.84 $33,802.31 $81,847.13 $592,561.66 $195,770.05 $27,246.81 $13,428.82

$5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00

$70,437.64 $95,756.82 $93,386.11 $80,048.54

$726,237.09 $1,370,864.33 $124,017.82 $1,543,937.36 $106,741.62 $1,542,726.37 $277,124.06 $1,602,316.94 $96,458.06 $1,159,367.15

$50,715.22 $68,945.07 $67,238.15 $57,635.08

$10,565.67 $14,363.56 $14,007.95 $12,007.31

$2,362,397.31Subsurface void/vault space for infiltration & detention (under lawn & sidewalk) $1,540,272.10Excavated bioswale with overflow to drainage system $540,032.53 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $564,884.60 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $739,677.86 Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $1,092,922.17Soil & substrate added to roof of existing parking structure $6,840,186.57 $342,009.33 $205,205.60 $342,009.33 $1,026,027.99 $8,755,438.82

$3,313,167.46Intention is to provide in-line subsurface storage vaults for existing deep culvert. Anticipated excavation approx. 10' deep beyond baseline excavation. Paved shallow & potable surface water feature above ("turning basin") with outflow to L3.16. $199,808.25 Excavated bioswale with overflow to drainage system $271,630.37 Excavated bioswale with overflow to drainage system $264,905.45 Excavated bioswale with overflow to drainage system $227,071.18 Excavated bioswale with overflow to drainage system $1,104,441.40Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,399,346.67Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $192,749.06 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,575,384.38Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $166,594.82 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,574,152.64Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $424,534.71 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,634,763.97Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $151,026.67 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,184,226.64Subsurface void/vault space for infiltration & detention (under parking, exterior spaces) to achieve 1.25" city stormwater runoff requirement $1,626,716.88Open "canal" feature approx. 5' deep beyond baseline excavation. Linked to surface water feature in L3.01. One natural landscaped bank, one gabion structure bank. 2 subsurface tie-ins to Lafitte St and 1 tie-in to Orleans Ave culvert. One pedestrian bridge. $5,069,116.26Subsurface void/vault space for infiltration & detention (under playing field). Excavation approx. 4' deep beyond baseline. $1,562,429.52Open "canal" feature approx. 5' deep beyond baseline excavation. Linked to surface water feature in L3.16. One natural landscaped bank, one gabion structure bank. 2 subsurface connections to receive inflow from Lafitte St. $312,461.12 Excavated bioswale with overflow to drainage system $108,740.12 Excavated bioswale with overflow to drainage system $1,357,500.56Open "canal" feature approx. 5' deep beyond baseline excavation. Linked to surface water feature in L3.18. One natural landscaped bank, one gabion structure bank. 3 subsurface connections to receive inflow from Lafitte St. One pedestrian Bridge $431,884.38 Subsurface void/vault space for infiltration & detention (under lawn/playing field) $379,360.75 Subsurface void/vault space for infiltration & detention (under lawn/playing field) $383,542.97 Open "canal" feature approx. 5' deep beyond baseline excavation. Linked to surface water feature in L3.21. One natural landscaped bank, one gabion structure bank. $2,745,597.69Open "canal" feature approx. 5' deep beyond baseline excavation. Linked to surface water feature in L3.24 with outflow into open drainage canal. One natural landscaped bank, one gabion structure bank. Two pedestrian bridges. $1,803,148.32Subsurface void/vault space for infiltration & detention (under lawn & sidewalk). Protect existing trees. $392,586.29 Subsurface void/vault space for infiltration & detention (under paved plaza). Replace urban landscaping & street furniture. $196,025.11 Subsurface void/vault space for infiltration & detention (under paved plaza). Replace urban landscaping & street furniture. $9,037,008.36presumed to be at discounted rated due to large volume $39,089,922.02 $1,954,496.10 $1,172,697.66 $1,954,496.10 $5,863,488.30 $50,035,100.18

• Building demolition and environmental remediation excluded $1,631,830.18 $1,174,920.43

$244,775.09

• Inlets from existing drainage system not included in cost estimate; DPW guidance required to estimate connection and street reconstruction costs. SF

Per SF

$110,150.73 $29,336.33

$79,308.71 $42,244.42

$16,522.65 $8,800.92

$144,543.16 $126,758.65

$31,221.40 $27,379.93

$43,363.05 $38,027.68

$29,486.87 $25,858.82

$734,137.71 $102,175.55 $50,358.07

$47,572.23 $125,063.16 $61,638.41

$66,072.55 $30,652.74 $15,107.45

$44,929.33 $3,678.33 $1,812.89

Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

25.38

• Urban park amenities not included in estimate

N 3.01 N 3.02 N 3.03

V 2.1 V 2.10 V 2.11 V 2.12 V 2.13 V 2.14 V 2.2 V 2.3 V 2.4 V 2.5 V 2.6 V 2.7 V 2.8 V 2.9

Open Space Green Roof Pavement

Pavement Pavement Open Space Pavement Open Space Open Space Pavement Open Space Pavement Pavement Pavement Pavement Open Space Pavement

NOPL NOPL NOPL SF

17416.87 34656.00 35162.89 87235.76

Per SF

36.88

VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site VA Site SF

20329.49 13281.70 128361.81 43898.09 35836.69 23169.95 23482.10 21640.16 14027.43 14426.28 19935.53 16503.13 64042.16 14264.98 453199.51

Per SF

36.32

0.40 0.80 0.81

3 0.25 1.5

1.20 0.20 1.21

52250.50 8663.98 52744.21

1935.20 320.89 1953.49

$120,950.24

$19,352.04

$122,093.09

$19,534.89

$39,069.79

$5,000.00

$703,257.80

0.47 0.30 2.95 1.01 0.82 0.53 0.54 0.50 0.32 0.33 0.46 0.38 1.47 0.33

1.5 1.5 3 1.5 3 3 1.5 3 1.5 1.5 1.5 1.5 3 1.5 28.5

0.70 0.46 8.84 1.51 2.47 1.60 0.81 1.49 0.48 0.50 0.69 0.57 4.41 0.49

30494.17 19922.50 385084.56 65846.99 107509.81 69509.68 35223.06 64920.32 21041.10 21639.37 29903.23 24754.64 192126.05 21397.43

1129.41 737.87 14262.39 2438.78 3981.84 2574.43 1304.56 2404.46 779.30 801.46 1107.53 916.84 7115.78 792.50

$70,588.35 $46,116.91 $891,399.44 $152,423.59 $248,865.30 $160,902.05 $81,534.87 $150,278.51 $48,706.24 $50,091.15 $69,220.44 $57,302.41 $444,736.23 $49,531.08

$11,294.14 $7,378.70 $142,623.91 $24,387.77 $39,818.45 $25,744.33 $13,045.58 $24,044.56 $7,793.00 $8,014.58 $11,075.27 $9,168.39 $71,157.80 $7,924.97

$22,588.27 $14,757.41 $285,247.82 $48,775.55 $79,636.90 $51,488.65 $26,091.16 $48,089.12 $15,586.00 $16,029.17 $22,150.54 $18,336.77 $142,315.59 $15,849.95

$5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00 $5,000.00

$203,294.91 $132,816.99 $7,023,695.19

$1,212,959.96

$145,140.28

$104,501.24

$21,771.09 Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

$39,508.29

$54,872.62

$226,349.55

$37,313.38

$224,438.87 $144,262.83 $199,355.33 $165,031.32

$12,624.69

$17,534.29

$72,328.93

$11,923.31

$142,649.84

$12,838.49

$17,831.23

$73,553.82

$12,125.24 Sub-Total General Conditions Contingency Inflation Design Fees Rough Order of Magnitude

$234,820.95

$411,714.90 Excavated bioswale with overflow to drainage system $1,212,959.96Soil & substrate added to roof of existing concrete library structure $888,955.57 Subsurface void/vault space for infiltration & detention (under parking lot) $2,513,630.43 $125,681.52 $75,408.91 $125,681.52 $377,044.56 $3,217,446.95 $312,765.67 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $206,070.01 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $1,324,271.16Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $7,612,325.94Tree allee at 20' O.C. Subsurface vaulted water storage under paving. $373,320.64 Excavated, paved "Water Square" to receive inflow from surrounding surface runoff and catch basins. $243,135.03 Subsurface void/vault space for infiltration & detention (under parking and drop off lanes.) $360,492.55 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $227,412.20 Demolish existing building. Subsurface void/vault space for infiltration & detention (under paving) $415,935.32 Tree allee at 20' O.C. Subsurface vaulted water storage under paving. $223,397.72 Subsurface void/vault space for infiltration & detention (parking lanes only) $306,801.59 Subsurface void/vault space for infiltration & detention (parking lanes only) $254,838.88 Subsurface void/vault space for infiltration & detention (full width under street; 1/2 parking, 1/2 travel lanes) $663,209.62 Demolish existing buildings on site. Excavated, paved "Water Square" to receive inflow from surrounding surface runoff and catch basins. $337,304.62 Tree allee at 20' O.C. Subsurface vaulted water storage under paving. $12,861,280.95 $643,064.05 $385,838.43 $643,064.05 $1,929,192.14 $16,462,439.62 NOTES For New Development sites, cost of new construction NOT included; cost estimate to assume minimal additional cost to achieve City storage requirements for new construction Demo cost as separate line item. If demo cost is not attainable please note as such. For Lafitte Greenway sites, assume baseline removal of 3' soil from all project areas. Add line item for disposal of potentially contaminated soil Add budget line item for additional finer-scale stormwater modeling per project. Water Depth column does not indicate depth of excavation; used for overall water storage calculation purposes only. Unit Cost Line Item Notes Excavavtion/CY Contaminated Soils Raintanks/CF Weir Control Structure Permeable Pavers -Vehicular Green Roof Assembly BioSwale Soils/CY Bed Planting Irrigation Tree Allee Sod

Notes Removal and Haul Off Site - based off of storage capacity with a 25% over excavation factor Additional Fees to Haul to a Certified Contaminated Dump Site - based on 25% of excavated Soils based on historical Eco Construction Servivces product R-Tank Assemblies - including open aggregate base, backfill, topping and associated connective piping and fabrics This is a plug number based on historicals to control the outflow of the detained 1.25" of rain fall to slowly enter the storm sewer over a 24 hour period - these will be costume to each site budget based on 80mm Eco Prioria Histiorical Numbers - aggregate base with sand swept jonts 18" of Lightweight Soils - Pine Straw Mulch - 3 Gallon / 1 Gallon Shrubs/Groundcover - Drainage Mat - NOTE: All water proofing by others 18" of Highly Permeable Soils with a Pine Straw Topping - based on historical numbers from previous projcets 4" Pine Straw Mulch with a mix of 3 Gallon - 1 Gallon - & 4" Pot (Shrubs and Groundcover) Design Build 100% Coverage 3.5" Street Trees that fall with in Parks and Parkways Standards - staking, gator bag, mulch included Bermuda Sod

Exclusions *** DEMO Not Included in this Budget New Parking Structures New Streets and or Parking Lots - except where Permeable Pavers are noted

Urban Water Design Components Basis of Stormwater Calculations and Estimates Type

Average Depth/SF

Type

Average Depth/SF

New Development

0.1 to 2 ft

Residual Space

3 ft

New buildings and sites store code minimum 1.25 inches More intensive storage at City Hall redevelopment sites

Interventions in courtyards, setbacks and open space between VA buildings Flow through planters, cisterns, subsurface storage, bioretention

• Demolition and environmental remediation (if required) are not included in cost estimate

• Included in Open Space category for costing purposes

• Cost of building design & construction not included

Pavement Storage

Structural water storage under parking, sidewalks and plazas.

1.5 ft

Allée of Trees

Trees planted in structural soil with pervous paving or in bioswales

• Estimate includes excavation, RainTanks, outlet to drainage system, and permeable paving.

• Included in Open Space category for costing purposes

• Inlets from existing drainage system not included in cost estimate; DPW guidance required to estimate connection and street reconstruction costs. • 25% over excavation for structural support and 25% contaminated soil disposal assumed in estimate.

Open Space Planted bioswales, open canals, and/or structural water storage under lawns and fields • Estimate includes excavation, RainTanks (as applicable), outlet to drainage system, basic plantings, and irrigation. • 25% over excavation for structural support and 25% contaminated soil disposal assumed in estimate. • Demolition and environmental remediation (if required) are not included in cost estimate. • Design features (such as lighting, seating, shade structure, etc) are not included in estimate.

3 ft

Green/Blue Roof

Landscaping or detention on rooftops

• Not included in cost estimate • Modeled as Low Impact Development runoff reduction, not storage volume

1.5 ft

Proposed Design Scenario VA Hospital Site - Duncan Plaza

New Development with Ambitious Storage

Roof Garden

Stormwater Park

Blue/Green Roof

Rain Garden Detention Basin

LEGEND Open Space Bioswale/Rain Garden Tree Water Path Plaza Permeable Paving Blue/Green Roof New Development New Building

Water Garden Permeable Paving

Subsurface Storage

Duncan Plaza

Duncan POrder laza of Magnitude Cost Estimate Preliminary Hard Costs Pavement & Green Space Water Storage Public Space Amenities System Inlets & Street Reconstruction Demolition Subtotal Soft Costs Design & Engineering Community Engagement & Outreach General Conditions Contingency Inflation Subtotal Total

ESTIMATED COST

NOTES

$5,000,000 $0 $0 $0 $5,000,000

Assume 25% over excavation & 25% contaminated soils to certified dump site Design features not included (fountains, lighting, plaza paving, seating, shade pavilions, etc.) City of New Orleans DPW to provide guidance Not in estimate/unknown (could include subsurface features)

$500,000 $0 $250,000 $500,000 $250,000 $1,500,000

Assume 10% of hard costs GNOF to provide guidance Assume 5% of hard costs Assume 10% of hard costs Assume 5% of hard costs

$6,500,000

New Development

Pavement Storage

Allee of Trees

Open Space

Residual Space

Green/Blue Roof

VA / City Hall

VA/City HOrder all Rof etMagnitude rofits Preliminary Cost Estimate Hard Costs Passive Green Infrastructure Public Space Amenities System Inlets & Street Reconstruction Demolition Environmental Remediation Subtotal Soft Costs Design & Engineering Community Engagement & Outreach General Conditions Contingency Inflation Subtotal Total

ESTIMATED COST

$14,500,000 $0 $0 $0 $0 $14,500,000

$1,450,000 $0 $725,000 $1,450,000 $725,000 $4,350,000

NOTES

Assume 10% of hard costs GNOF to provide guidance Assume 5% of hard costs Assume 10% of hard costs Assume 5% of hard costs

$18,850,000

New Development

Pavement Storage

Allee of Trees

Open Space

Residual Space

Green/Blue Roof

Proposed Design Scenario Lafitte Greenway - Armstrong Park

Soft & Hard Edges

Accessible Water

Water Square

Improved Canal

Stormwater Wetlands LEGEND Open Space Bioswale/Rain Garden Tree Water Path Plaza Permeable Paving Blue/Green Roof New Development New Building

Subsurface Storage

Bioswales New Development with Ambitious Storage

Lafitte Blueway

Lafitte Blu ewaof y Magnitude Cost Estimate Preliminary Order Hard Costs Passive Green Infrastructure Public Space Amenities System Inlets & Street Reconstruction Demolition Environmental Remediation Subtotal Soft Costs Design & Engineering Community Engagement & Outreach General Conditions Contingency Inflation Subtotal Total

ESTIMATED COST

$32,200,000 $0 $0 $0 $0 $32,200,000

$3,220,000 $0 $1,610,000 $3,220,000 $1,610,000 $9,660,000

NOTES

Assume 10% of hard costs GNOF to provide guidance Assume 5% of hard costs Assume 10% of hard costs Assume 5% of hard costs

$41,860,000

New Development

Pavement Storage

Open Space

Armstrong Park

ArmstronOrder g Paof rkMagnitude Limited ACost dapEstimate tation Preliminary Hard Costs ESTIMATED COST Passive Green Infrastructure $800,000 Public Space Amenities $0 $0 Street Reconstruction & Subsurface Connectio Demolition $0 Environmental Remediation $0 Subtotal $800,000 Soft Costs Design & Engineering Community Engagement & Outreach General Conditions Contingency Inflation Subtotal Total

$80,000 $0 $40,000 $80,000 $40,000 $240,000

NOTES

Assume 10% of hard costs GNOF to provide guidance Assume 5% of hard costs Assume 10% of hard costs Assume 5% of hard costs

$1,040,000

New Development

Pavement Storage

Open Space

H&H Modeling

DRAFT

MIN Scenario Storage Targets Downtown

Downtown Impact Area Base Flood Volume 56.3 Ac Ft MID Scenario Flood Reduction

10.4 Ac Ft (-19%)

Total Storage Target

23.9 Ac Ft

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MID Scenario Storage Targets (Proposed Scenario) Downtown

Downtown Impact Area Base Flood Volume 56.3 Ac Ft MID Scenario Flood Reduction

14.2 Ac Ft (-25%)

Total Storage Target

51.9 Ac Ft

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MAX Scenario Storage Targets Downtown

Lafayette Square

Downtown Impact Area Base Flood Volume 56.3 Ac Ft MAX Scenario Flood Reduction

15 Ac Ft (-27%)

Total Storage Target

58.6 Ac Ft

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MIN Scenario Storage Targets Lafitte

Lafitte Impact Area Base Flood Volume

123.6 Ac Ft

MIN Scenario Flood Reduction

6.8 Ac Ft (-6%)

Total Storage Target

20.6 Ac Ft

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MID Scenario Storage Targets Lafitte

Lafitte Impact Area Base Flood Volume

123.6 Ac Ft

MID Scenario Flood Reduction

16.4 Ac Ft (-13%)

Total Storage Target

40.4 Ac Ft

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MAX Scenario Storage Targets (Proposed Scenario) Lafitte

Lafitte Impact Area Base Flood Volume

123.6 Ac Ft

MAX Scenario Flood Reduction

36.5 Ac Ft (-30%)

Total Storage Target

108.6 Ac Ft

Full Extent

Window

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

DRAFT

MAX Scenario Storage Targets (Proposed Scenario)

Br oa dS t

Bayo u St J ohn

Lafitte

MAX Scenario Flood Reduction

36.5 Ac Ft (-30%)

Total Storage Target

108.6 Ac Ft

Or lea ns Av e

Ca na lS t

Ga lve zS t

123.6 Ac Ft

Lafitte Impact Area Base Flood Volume

Open Space Water Level

Residual Space Pavement

Green Roof New Development

Green Roof

Modeling Scenarios and Results Impact Areas

Report Legend

MAX Downtown + MID Lafitte

MAX Downtown + MAX Lafitte (routing from St Louis Culvert)

9.1

MAX Downtown + MAX Lafitte (routing from Orleans Ave Culvert 2)

9.2

MAX Downtown + MAX Lafitte (routing from Orleans Ave Culvert 1)

9.3

MAX Downtown + MAX Lafitte (routing from Orleans Ave Culvert 1 + Upsized Pipes)

D y d rLouis MAX Downtown (without Square) + MAX Lafitte (routing fromo St a s S Culvert) O I Lafayette

12.1

Proposed Scenario: MID Downtown (upsized pipes 2) + MAX Lafitte (routing from Orleans Ave Culvert + upsized pipes)

Minimum Scenario: MIN Downtown + MIN Lafitte

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 3 - 6 in

Residual Space

6 - 9 in

Pavement

Flood Volume Reduction 43 Ac Ft

9 - 12 in New Development

> 12 in Green Roof

lS t

pa m

IBERVILLE

FRENCH QUARTER

eA ve

la A ve

lan

D IM OW PA N C TO T W A N RE A

t M W PA N CENTRAL MAX Lafitte (routing from Orleans C T O Ave Culvert) BUSINES S T W A N DISTRICT R E (upsized pipes 2) + MAX Lafitte (routing Proposed Scenario: MID Downtown from Orleans Ave Culvert + upsized pipes) A

Open Space

Loyo

la A ve

MIS SIS SIPPI RIVER

1 - 3 in

MIS SIS SIPPI RIVER

FRENCH QUARTER

MAX Downtown (upsized pipes 1 without Lafayette Square) + MID Lafitte

< 1 in

TUL ANE - GRAVIER

8.5

/I -1 0

lS ANE - GRAVIER TUL(upsized t Square) + MID Lafitte MAX Downtown pipes 1 without Lafayette IBERVILLE

8.4

lv Ga

MAX Downtown (upsized pipesT2u lwithout Lafayette Square) + MID Lafitte an eA v MAX Downtown (upsized pipes 1 withouteLafayette Square) + MID Lafitte

8.3

St pa m Ra s

8.2

8.1 DuncanPlazaOutfall

MID Downtown (upsized pipes 2) + MIN Lafitte

7.2

MID Downtown + MIN Lafitte

7.1

St Cu lve rt MID Downtown (upsized pipes 1) + MIN Lafitte

t. L ou is

Drainage Pump Station 2

MID Lafitte

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2S

/I -1 0

MIN Lafitte

L IM AFI PA T T CT E AR

TREME - L AFIT TE

MAX Downtown

MID Downtown

MIN Downtown

1 Existing

Scenario

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth 0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MIN Downtown le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MID Downtown le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MIN Lafitte le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MID Lafitte le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Lafitte

Routing from Orleans Ave culvert

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Minimum Scenario: MIN Downtown + MIN Lafitte le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MID Downtown + MIN Lafitte le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown + MID Lafitte le

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown + MID Lafitte

Without Lafayette Square and Downtown pipes upsized

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown + MAX Lafitte

Without Lafayette Square and Lafitte routes from St Louis culvert

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown + MAX Lafitte Lafitte routes from St Louis culvert

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

MAX Downtown + MAX Lafitte

Lafitte routes from Orleans Ave culvert with upsized pipes

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Proposed Scenario: MID Downtown + MAX Lafitte Lafitte routes to Orleans Ave culvert and both sites have upsized pipes

Or s

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Drainage Pump Station 2 EA

Open Space

3 - 6 in

Residual Space

Pavement

9 - 12 in New Development

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in Green Roof

0 - 3 in

3 - 6 in

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

Area with significant elevation change since city SWMM model was created Major Drainage Line

18 - 24 in

Infinite Storage Test Base Flood Volume: 138 Ac Ft

Drainage Pump Station 2 EA

3 - 6 in

9 - 12 in

rt pa m Ra /I -1 0 e e

FRENCH QUARTER

IBERVILLE

Loyo

la A ve

eA ve

lan

D IM OW PA N C TO T W A N RE A

CENTRAL BUSINES S DISTRICT

6 - 9 in

lS t

MIS SIS SIPPI RIVER

ras S t

MIS SIS SIPPI RIVER

la A ve Poyd

Flood Depth Reduction from 10-year, 24-hour Design Storm Baseline 1 - 3 in

FRENCH QUARTER

Loyo

D IM OW PA N C TO T W A N RE A

< 1 in

lv N

/I -1 0 e e

eA ve

IBERVILLE

lan

TUL ANE - GRAVIER

lS t

lv Ga N

TUL ANE - GRAVIER Tu

Drainage Pump Station 2

L IM AFI PA T T CT E AR

TREME - L AFIT TE

L IM AFI PA T T CT E AR

TREME - L AFIT TE

Poyd

ras S t

CENTRAL BUSINES S DISTRICT

Flood Depth > 12 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Civic Center Existing Conditions 2 Year, 24 Hour Event & 5 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Flood Depth 2 Reduction Year, 24 Hour Event 3 1- -62inin

NOPL

CITY HALL

SUPERDOME

0 < -1 3inin

TULANE MEDICAL CENTER H O S P I TA L

6 - 92 in - 3 in

Open MajorSpace Drainage LinePavement

Flood Depth 5 Year, 24 Hour Event 9 - 12>in3 in

12 - 15 in

15 - 18 in

18 - 24 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Civic Center Existing Conditions 10 Year, 24 Hour Event & 100 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Flood Depth 10 Reduction Year, 24 Hour Event 3 1- -62inin

NOPL

CITY HALL

SUPERDOME

0 < -1 3inin

TULANE MEDICAL CENTER H O S P I TA L

6 - 92 in - 3 in

Open MajorSpace Drainage LinePavement

Flood Depth 100 Year, 24 Hour Event 9 - 12>in3 in

12 - 15 in

15 - 18 in

18 - 24 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Duncan Plaza Intervention Flood Reduction 2 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Open Space

NOPL

CITY HALL

SUPERDOME

Flood Depth Reduction < 1 in

TULANE MEDICAL CENTER H O S P I TA L

1 - 2 in Pavement

Flood Depth 2 - 3 in

> 3 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Duncan Plaza Intervention Flood Reduction 5 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Open Space

NOPL

CITY HALL

SUPERDOME

Flood Depth Reduction < 1 in

TULANE MEDICAL CENTER H O S P I TA L

1 - 2 in Pavement

Flood Depth 2 - 3 in

> 3 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Duncan Plaza Intervention Flood Reduction 10 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Open Space

NOPL

CITY HALL

SUPERDOME

Flood Depth Reduction < 1 in

TULANE MEDICAL CENTER H O S P I TA L

1 - 2 in Pavement

Flood Depth 2 - 3 in

> 3 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Duncan Plaza Intervention Flood Reduction 100 Year, 24 Hour Event

JUNG HOTEL

FORMER CHARITY H O S P I TA L

JUNG HOTEL

TULANE MEDICAL CENTER H O S P I TA L

VA S I T E

FORMER CHARITY H O S P I TA L

VA S I T E

NOPL

CITY HALL

SUPERDOME

Open Space

NOPL

CITY HALL

SUPERDOME

Flood Depth Reduction < 1 in

TULANE MEDICAL CENTER H O S P I TA L

1 - 2 in Pavement

Flood Depth 2 - 3 in

> 3 in

0 - 3 in

3 - 6 in

Major Drainage Line

6 - 9 in

9 - 12 in

12 - 15 in

15 - 18 in

18 - 24 in

Combined Scenario Results All Scenarios*

Scenario 1 2 3 4 5 6 7 8 8.1 8.5 9 9.3 10 11 12.1 13

*Duncan Plaza Intervention scenario model run was added after publication of report and is not included in this table

Downtown Impact Area Flood Reduction Ac Ft Ac Ft 56.3 45.9 42.1 41.3 50.7 48.8 38.6 36.9 13.6 26.1 25.2 20.2 28.0 39.4 26.1 42.9

10.4 14.2 15.0 5.6 7.5 17.7 19.4 42.7 30.2 31.1 36.1 28.3 16.9 30.2 13.4

-19% -25% -27% -10% -13% -31% -34% -76% -54% -55% -64% -50% -30% -54% -24%

Lafitte Impact Area Flood Reduction Ac Ft Ac Ft 123.6 114.2 111.4 110.6 116.8 107.2 106.9 97.3 79.4 89.6 86.4 72.0 87.2 87.0 75.7 108.4

9.3 12.1 13.0 6.8 16.4 16.7 26.3 44.2 34.0 37.2 51.6 36.4 36.5 47.9 15.2

-8% -10% -10% -6% -13% -14% -21% -36% -28% -30% -42% -29% -30% -39% -12%

Procella Design, LLC

Downtown Stormwater Opportunities Modeling Report August 7, 2020

Introduction:

The Greater New Orleans Foundation (GNOF) hired Waggnonner and Ball Architects and Environments (WBAE) to produce a planning study that reflected downtown stormwater opportunities. WBAE in turn hired Procella Design LLC to conduct the stormwater modeling portion of the planning study. Procella used the City of New Orleans’ Stormwater Management Model to compare existing conditions with the results of proposed interventions. The proposed interventions include pervious parking, underground storage, blue roofs, and depressed parks in and around City Hall, Duncan Plaza, the Veterans Hospital site, Louis Armstrong Park, the Lafitte Greenway, and Lafayette Square.

Abbreviations:

Figure 1: Screenshot of the model extents in EPA-SWMM Procella used EPA-SWMM to model the proposed condition. The base model appears to have been built in PC- SWMM, the proprietary version of the SWMM software. This conclusion is based on the availability of the associated shapefiles available to the planning team, provided by DPW. Procella discussed with WBAE how to export and visualize data. As results become available, WBAE would join the node max HGL results with the node shapefile in Arc GIS. WBAE would then create raster flood maps or color code the nodes.

CBD – Central Business District DPS – Drainage Pump Station DPW – Department of Public Works EPA – Environmental Protection Agency GNOF – Greater New Orleans Foundation HGL – Hydraulic Grade Line SWMM – Stormwater Management Model WBAE – Waggonner and Ball Architecture and Environments

Base Model:

Rainfall:

On June 12, 2020, DPW provided the planning team with DPS 2, 3, 4 and 19 model and the associated shapefiles. The model was called “DPS02_03_04_19ExRevSACal_10Yr”, indicating some level of calibration undisclosed by Ardurra, the firm responsible for maintaining the City of New Orleans’s SWMM th model. This model covers roughly the east bank of New Orleans proper from the 17 Street Canal to the th Industrial Canal and parts of Jefferson Parish that feed into the 17 Street Canal. The model shows in detail Gentilly, the French Quarter, the CBD, Treme, some of Mid-City, the Bywater, the Marigny, and St Roch neighborhoods. The detailed part of the model stretches from the lake to the river, from Bayou St John to the industrial Canal, and bounded to the south by roughly by the elevated highway BUS 90. The rough coverage is hatched and the detailed coverage is almost solid black in Figure I.

Procella ran existing conditions model with Time Series “SCSTypeIII_24hr_10yr_8p5in” Based on New Orleans’s location, rainfalls are intense so a SCS Type III distributions is used. Also based on location, a 24hour storm with a 10% chance of occurring every year (referred to as a 10-year storm), has a total precipitation of 8.5 inches. 10-year 24-hour design storms are typically used to design stormwater infrastructure.

Procella Design, LLC

1106 General Taylor St New Orleans, LA 70115

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1106 General Taylor St New Orleans, LA 70115

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Figure 2: Hyetograph of Rainfall for 10-year 24-hour design storm for New Orleans area.

Time

Rainfall (inches)

Cumulative Rainfall (inches)

0:53

1:53

2:53

3:05

3:17