1
December 2011
Transit-Oriented Stormwater Management 41st - 50th & Spruce - Market Ann-ariel vecchio, Mit, master in city planning ‘12 stephen kennedy, Mit, Master in city planning ‘12
11.314 water, landscape, & urban design
2
December 2011
Project Outline 01
Design process
02
site analysis: hydrology
4-8
built environment
9-15
Transportation 03
3
16
Watershed design conceptual diagram
17
green transit corridor
18
Market Street
19-21
Bus Stops / Streetscape
22-24
Parking Lots
25-27
04
Greened Acres Evaluation
28
05
Implementation & Management
29
06
conclusions
30
Appendix A
31
PUBLIC REALM
INSTITUTIONAL REALM
LINEAR / DIRECTIONAL
POLYGON / CORNER
Design Process
MULTIDIMENSIONAL
ALLEYS
SPATIAL CONDITIONS
WIDE
NARROW
LINEAR / DIRECTIONAL
PRIVATE REALM
ELONGATED
POLYGON / CORNER
OPEN SPACES
PARKING LOTS
STREETS WIDE
Through the analysis of the site, we identified a series of typologies that characterize and organize different physical attributes and potential opportunity sites within the project area. They are: linear (streets and alleyways), polygons (open spaces and parking lots), and multidimensional (schools, businesses, and homes).
RECTANGULAR
MULTIDIMENSIONAL
ALLEYS
SMALL
LARGE
WIDE
NARROW
Mapping the typologies within the project area revealed a concentration and convergence of these types along the main sewer line, which is also the buried floodplain of the Mill Creek.
NARROW
ELONGATED
RECTANGULAR
OPEN SPACES
In this area, we identified specific opportunities and began to develop concepts for stormwater management that combined different typologies or approaches.
PARKING LOTS
SMALL
LARGE
WIDE
SCHOOLS
NARROW
BUSINESSES
LARGE
HOMES
SMALL
SCHOOLS LARGE
3 Further documentation of the design process is included as Appendix A.
PRIVATE REALM STREETS
EEN OGRAMS NCEPTUAL AMEWORK
NSTITUTIONAL REALM
SPATIAL CONDITIONS
GREEN PROGRAMS CONCEPTUAL FRAMEWORK
LARGE
SMALL
BUSINESSES SMALL
LARGE
HOMES LARGE
SMALL
LARGE
After sharing these ideas with project teams working in other areas within the Mill Creek watershed, it became evident that many of the conditions or typologies within our project site are present across the Mill Creek watershed. However, the presence of transportation infrastructure, public transit, and parking make the Spruce to Sansom sewershed unique. Since other teams elaborated similar ideas to those in our initial concepts for stormwater management, we chose to focus on the unique characteristics of the project area. The following presents analysis of the project area and our proposal for a transit oriented stormwater management approach.
x N
0 100
400
4
600
MARKET ST
x CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
x
x
x
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
x x
02
site analysis hydrology
Elevation above sea level
x
100’
Heightmap Topography
The Neighborhood’s low-lying areas clearly illustrate the presence of mill creek’s buried flood plain. high Points low Points
2’ Contours
x
40’
The low points above were most likely part of the mill creek bed, about 3/4 of a mile from the creek’s mouth at the schuylkill river.
x N
0 100
400
5
600
MARKET ST
x CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
x
x
x
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
x x
02
site analysis hydrology
Elevation above sea level
x
100’
Topography Lightmap
high Points low Points
2’ Contours
x
40’
Clear point of subsidence at the cvs parking lot in the brightest point in our sewershed.
N
0 100
400
6
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
02
SEWERSHED
CONTOURS (2’ INTERVAL)
SEWER MAIN
SECONDARY SEWER LINE
site analysis hydrology
The Municipal Drainage System
Sewersheds The Philadelphia Water Department uses sewersheds to define primary flows to the municipal drainage system. However, to understand the true drainage patterns in a watershed, one needs to look beyond these engineered boundaries.
primary flows
N
0 100
400
7
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
CALCULATED SURFACE FLOWS
02
site analysis hydrology
Calculated Flows
defining area drainage Calculating stream flows highlights the characteristics of the watershed. Following these flows, it is evident that surface water in the neighborhood drains to the site’s center along the sewer main. This demonstrated that multiple sewersheds converged toward our original sewershed.
primary flows
N
0 100
400
8
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
02
site analysis hydrology
Sewer Inlets
A b
subsistence at farragut & sansom Pooling on Farragut st.
578
Inlets in neighborhood
19
Intersections with more than four inlets Indicate under sized or non-functional inlets, high volume, or drainage from all directions. A reduction in the total volume of water flowing to these inlets is an important objective.
A
b
N
0 100
400
9
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
02
site analysis Built Environment
Total Area
9,700,000
sq ft
222 Acres
N
0 100
400
10
600
the Built Environment’s Impact on drainage The high amount of impervious, or paved, surfaces in this area creates a large volume of water that flows directly into city sewers and, eventually, into the Schuylkill River. However, this also indicates that the implementation of stormwater management BMPs has huge potential to reduce sewer overflow events. The following pages of land cover analysis describe the components of these impervious surfaces.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
02
site analysis Built Environment
Impervious data from philadelphia water dept
/ city of philadelphia
Impervious
Pervious
170 acres
52 acres
77%
23%
N
0 100
400
11
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
Impervious 02
site analysis Built Environment
Streets
35.7 acres
21%
Pervious
Streets are a significant proportion of impervious surface and are found throughout the project area. Due to their linear form, interventions in parking lanes and other areas along the street edge have the potential to capture water before it flows into sewer inlets on each block.
N
0 100
400
12
600
Although sidewalks make up a smaller proportion of impervious surface, their location adjacent to streets creates the opportunity to develop interventions that can treat run-off from multiple locations – streets, sidewalks, and homes. In addition, stormwater management BMPs can also be designed to improve the pedestrian environment and improve the public realm. In the project area, the width of sidewalks (sometimes as wide as 17’) along east-west streets, such as Market, Chestnut, and Walnut, provide ample space for visible BMPs that can provide multiple benefits.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
Impervious 02
site analysis Built Environment
Sidewalks
Pervious
35.7 acres
20.4 acres
21%
12%
N
0 100
400
13
600
Buildings represent a proportion of impervious surfaces almost equal to streets and sidewalks combined. Therefore, individual action on private property is also significant. However, since most buildings are small in size, a stormwater management strategy that addresses buildings requires the participation of many individuals. On many blocks along the sewer line, large-footprint buildings are often adjacent to open areas and parking lots.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
Impervious 02
site analysis Built Environment
Buildings
Pervious
35.7 acres
20.4 acres 54.4 acres
21%
12% 32%
N
0 100
400
14
600
Parking lots represent 10% of the project area. While they range in size from small residential lots to larger lots that service commercial areas, the large lots cluster along the main line of the sewer system, which is also the buried flood plain of the Mill Creek. These large plots of land also lie at low points in the project area and present the potential to remove significant amounts of impervious surface or site other BMPs.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
Impervious 02
site analysis Built Environment
Parking
Pervious
35.7 acres
20.4 acres 54.4 acres
54.4 acres
21%
12% 32%
10%
N
0 100
400
15
600
The site features a significant amount of pervious area, including public open space as well as private spaces in block interiors and under utilized vacant lots. Much of the pervious surface could be improved to function as green stormwater infrastructure while providing aesthetic benefits in the public realm.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
Impervious 02
site analysis Built Environment
Pervious
Pervious
35.7 acres
20.4 acres 54.4 acres
54.4 acres
52 acres
21%
12% 32%
10%
23% Public Open Space Private Open Space Vacant Lots
N
0 100
400
16
600
In addition to the natural hydrological system and built environment, several public transit lines cross through the project area. Transit stops define nodes that neighborhood residents use on a daily basis. Bus stops often coincide with the location of inlets at low points on many blocks.
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST LOCUST
50 th ST FARRAGUT ST
02
site analysis transportation
Public Transit
Market21 Bus Frankford Elevated Rail Line to subway
Penn’s Landing To 69th Street Transportation Center
31 Bus
64 Bus
City Hall To 76th-City
49th-Parkside To Pier 70
N
0 100
400
transportation infrastructure
03
17
600
+
public transit
conceptual diagram
Transit-Oriented Approach
+
surface parking lots
+
stormwater Bmps
=
effective Green stormwater Infrastructure
design concept Given that multiple transit lines and transportation corridors cross the project area, the opportunity emerges to combine best management practices for stormwater management with public and private transportation. BMPs can be incorporated into transportation infrastructure, can enhance public transit facilities, and can take advantage of large parking lot surfaces.
Furthermore, the fact that high volumes of commuter traffic flow along Market, Chestnut, and Walnut Streets every day makes BMPS along these routes highly visible.
N
0 100
to subu
400
18
600
rbs
MARKET
ST.
to cent e
CHESTNUT ST
41st ST
r cit y
SANSOM ST
WALNUT ST
to cent e to subu
r cit y
rbs
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
to clark park & trolley lines
03
site Design
Green Transit Corridor
Key
Rail rain garden
tree trench
BMP Bus Stop
bioswale
pervious parking lot
N
0 100
400
19
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
03
site Design
Market Street Wavegardens
Key
Rail rain garden
tree trench
BMP Bus Stop
bioswale
pervious parking lot
20
At 46th St. emerges and runs along an elevated track to the west along Market St. Between 50th & Farragut St., the tracks add up to 84,000 sq ft (almost 2 acres) of impervious surface. Run-off polluted by contact with heavy metals of the cars and rails is piped directly through downspouts into the sewer system. Because these pipes are exposed just above the pylons, they could be disconnected and redirected through green stormwater infrastructure systems.
03
site Design
Market Street Wavegardens
The Market St. median also presents opportunities to locate infrastructure and enhance the under utilized space beneath the elevated rail. Precedent for public art exists on painted pillars near the station entrances. Working in partnership with the Mural Arts Program or other arts organizations, stormwater infrastructure can showcase community artwork along the elevated rail corridor.
21
Precipitation
Elevated track run-off
Evapotranspiration
soak
store
divert
street & Sidewalk run-off infiltration
overflow diversion
03
site Design
Market Street Wavegardens
elevated track run-off
cistern
cascading rain garden
Each section of track contributes around 130 cubic feet of run-off during a 1� storm that is sent directly into the combined sewer system from downspouts in the track pylons.
By disconnecting the track downspout at the base of each pylon, stormwater run-off can be diverted into adjacent cisterns with a capacity of 950 gallons - a volume that holds 90 percent of run-off from each section of track during a 1� storm.
Rain gardens feature hardy local plant palette that filter stormwater, but also build upon a tradition that incorporates art into the public realm. The planters provide a surface for local artwork, while drawing attention to the urban hydrologic cycle and stormwater management in Philadelphia.
N
0 100
400
22
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
03
site Design
Public Transit Green Way
Key
Rail rain garden
tree trench
BMP Bus Stop
bioswale
pervious parking lot
23
Four bus lines cross the project area. The 21 travels east and west on Walnut and Chestnut Streets, while the 31 and 64 travel north-south on Farragut Street and intersect with the 46th Street El station. Because most bus stops in the project area do not have shelters and coincide with low points and sewer inlets on many block corners new shelters could be designed to divert or intercept run-off from streets and sidewalks before it flows into sewers. Green stormwater infrastructure along these highly trafficked routes would also be visible to many residents and can treat run-off from relatively wide streets.
03
site Design
Public Transit Green Way
The creation of bus stop shelters can also provide the location for interpretive signage about stormwater issues in Philadelphia and public art. Precedent for creative bus stops exists on stylized shelters in Center City. Working in partnership with the Next Fab Studio or other arts organizations, stormwater infrastructure can showcase water sculptures or other artwork along bus route corridors.
24
sidewalk run-off D
divert
soak B C
Street run-off
E A
C B
store
D
roof run-off
03
site Design
Public Transit Green Way
greened streets
bmp bus stops
A combination of pervious soft and hardscape can treat both a city block and adjacent streets.
Feature green or stylized roofs that direct stormwater to cisterns for storage and distinctive signage announcing the bus stop. Also the location for public art and interpretive signage about stormwater management.
A b C D E
bmp bus stops tree trenches & swales pervious parking lane subsurface vault bump-out & raised intersection
N
0 100
400
25
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
03
site Design
Greened Grocery Lot
Key
Rail rain garden
tree trench
BMP Bus Stop
bioswale
pervious parking lot
Over 15 surface parking lots exist on blocks along the main sewer line and the Mill Creek burried flood plain. These lots illustrate a pattern of demolition as buildings were removed over time due to deterioration and subsistence problems. Because they lie at low points in the project area, they not only present the opportunity to remove large areas of impervious surface, but to also site green stormwater infrastructure projects that can easily treat an entire block or more.
03
site Design
Greened Grocery Lot
The parking lot at 44th and Walnut is one such example. Once the location of cave-ins, many residents now frequent the lot and grocery store. At 37,000 sq ft, the lot presents a significant opportunity to reduce run-off and improve the aesthetic qualities of the area. The development of green stormwater infrastructure systems in parking lots allows for projects where a large area can be addressed with the cooperation and partnership of one property owner. In addition, they create the potential to network projects and divert water from multiple blocks.
26
27
roof run-off
evapotranspiration
parking lot run-off
soak infiltration sidewalk run-off
store
street run-off
subsurface vault
A
corner
03
B
divert
wide edge
site Design
Stormwater Parking Lots
C
corner edge
D
strips
greened blocks
parking lot design
The construction necessary to treat an entire city block can fit within a large parking lot.
Improvements occupy 20% of the lot and manage stormwater from the entire block.
A b C D E
corner wide edge Corner edge strips pixels
A subsurface vault adds storage capacity and captures water from the street and surrounding blocks. Tree trenches add continuity to the stormwater corridor and allow for infiltration.
E
pixels
Decision Criteria development pressure
block location infiltration
N
0 100
400
28
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
04
direct benefits from pilot projects
greened acres evaluation
Total Greened Acres : acres of impervious surface
that are
retrofitted to connect to green stormwater infrastructure systems instead of flowing directly into sewers
short-term replication
long-term replication
5.5 Acres 78 Acres
600 Acres
Greened area from the Market Street Wavegarden segment, Public Transit Greenway block, and Greened Parking Lot described above.
Potential greened area from application of similar BMPs on every block along the Market-ChestnutWalnut commuter corridor.
Additional greened area from application of similar BMPs along the Green Transit Corridor (as shown above in green).
COMPONENTS
PROGRAM
PLAYERS
FINANCING
ECO-BENEFITS PRIORITIZATION
INFILTRATION PLANTERS
PERVIOUS PARKING LOTS
PERVIOUS PAVING
TYPE ONE
GREEN ROOF
JOINT CONSULTATION
PHILADELPHIA WATER DEPT (PWD)
FINANCING
DEPARTMENT OF STREETS
DESIGN (SURFACE LOT & PUBLIC REALM COMPONENTS)
PARKING AUTHORITY
CONSTRUCTION
SEPTA
MUNICIPAL AUTHORITIES
SOLICITATION FOR PARTICIPATION
BIOSWALES
CISTERNS
BMP BUS STOPS
PRIORITIZATION CONSULTATION WITH ADJACENT NEIGHBORS
SIDEWALK BUMP-OUT SIGNAGE SEATING
RAIL RAIN GARDEN
TRANSIT STOP PUBLIC ART
TYPE TWO
COODINATED PUBLIC REALM
LANDSCAPE ARCH. FIRM U. PENN LANDSCAPE NEXTFAB STUDIO
DESIGN & PUBLIC ARTS
DISCONNECTED DOWNSPOUTS
MAINTENANCE
REDUCED WATER BILL
RECLAIMING PARKING SPOTS / REMOVAL OF IMPERVIOUS SURFACE DESIGN: LANDSCAPING & BUS STOPS
MURAL ARTS PROGRAM NON-RESIDENTIAL PROPERTY OWNERS (COMMERCIAL) RESIDENTIAL PROPERTY OWNERS
PRODUCTION & CONSTRUCTION MAINTENANCE
CO-BENEFITS
05
Implementation
Public-Private Partnership
Public + Private + Arts + Awareness Each green infrastructure strategy can be implemented through the collaboration of public and private stakeholders. The diagram above outlines various roles during different phases of implementation.
ONE-TIME BILL CREDIT MUNICIPAL BUDGET STATE FUNDING
FINANCING
COMMUNITY STAKEHOLDERS
SUBSURFACE VAULTS
GRANT PROGRAM
FEDERAL GRANTS
29
N
0 100
400
30
600
MARKET ST
CHESTNUT ST
41st ST
SANSOM ST
WALNUT ST
LOCUST ST
SPRUCE ST
50 th ST FARRAGUT ST
06
Conclusions
Economic Benefits data from anna schall, bryn mawr supplemental economic analysis of mill creek watershed team b’s stormwater control designs
Increase in home prices
low Additional yearly Parking lot maintenance costs
Reduced annual stormwater fees
+9%
$50/acre
$816
Tree planting has been found to increase home prices by 9%.
Installation of pervious paving has been estimated to increase yearly maintenance costs from $150 to $200 / acre. It also reduces road salt use.
Commercial property owners are now charged a variable rate based on impervious coverage, which incentivizes them to install green stormwater infrastructure – a BMP on 10% of the pilot parking lot saves $816 annuallly.
31
MARK E
T
LU D LOW
CH E STN
SAN SO
UT
M
WALNU T
FARRAGUT ST
LOC U S T
Appendix A S PRU CE
Spatial Conditions
Open Space Alleyways & Vacant Lots Parking Lots
32
Spatial Conditions
Block Sheds
Appendix A
Spatial Conditions
Rowhouses with Stoops
Rowhouses with Porches
Rowhouses with Front Yards
MARK E
LU D LOW
CH E STN
SAN SO
WALNU
M
T
LOC U S T
S PRU CE
Spatial Conditions
Block Typologies Appendix A
UT
T
Rowhouses in Courtyards
Detached Houses with Front Yards
Sides of Houses
Rows of Stores
Apartment Buildings
Mixture of Building Types
33 Large, FreeStanding Building
34
1
2
4 3
1
ROWHOUSES WITH SIDEYARDS, PORCHES, & BACK ALLEYS.
2
HIGHSCHOOL WITH TRACK; U-HAUL PARKING LOT.
3
LARGER SURFACE PARKING LOTS FOR MIXED-USE AREA.
4
EMPTY LOT AND SCRAP-YARD.
Block Typologies Subwatershed A
Rowhouses with Stoops
Appendix A
Rowhouses with Porches
Rowhouses with Front Yards
Rowhouses in Courtyards
Detached Houses with Front Yards
Sides of Houses
Rows of Stores
Apartment Buildings
Mixture of Building Types
Large, FreeStanding Building
35
1 2
1
COURYARD HOUSING, ELEVATED RAIL TO SUBWAY, TOWERS.
2
SURFACE PARKING LOTS ON ALMOST EVERY BLOCK.
3
EMPTY LOTS CREATE ‘SWISS CHEESE’ EFFECT ON BLOCKS.
3
Block Typologies Subwatershed B
Rowhouses with Stoops
Appendix A
Rowhouses with Porches
Rowhouses with Front Yards
Rowhouses in Courtyards
Detached Houses with Front Yards
Sides of Houses
Rows of Stores
Apartment Buildings
Mixture of Building Types
Large, FreeStanding Building
36
1
SURFACE PARKING & OPEN SPACE THROUGHOUT BLOCKS.
2
WIDE STREETS WITH PARKING ON BOTH SIDES; CENTRAL COURTYARD.
3
LARGER INSTITUTIONS WITH STREETSIDE OPEN SPACES.
1 2
Block Typologies
3
Subwatershed D
Rowhouses with Stoops
Appendix A
Rowhouses with Porches
Rowhouses with Front Yards
Rowhouses in Courtyards
Detached Houses with Front Yards
Sides of Houses
Rows of Stores
Apartment Buildings
Mixture of Building Types
Large, FreeStanding Building
37
Spatial Conditions
Multiblock Combination
Opportunities
Surface & Subsurface
OR MARK E
T
LU D LOW
CH E STN
UT
Market St. Medians
+
+
SAN SO
WALNU
M
Small Commerical
T
LOC U S T
+ S PRU CE
Block Edges
Appendix A
In Between Buildings