Christopher Hytha

CENTRE SQUARE STATION Reimagining Transit and the Public Realm in the Heart of Philadelphia Chris Hytha

Adviser Katie Broh

CONTENTS 1. SITE ANALYSIS

1-6

6. SITE

15-16

2. RESEARCH

7-8

7. STATIONS

17-20

3. INITIAL REVIEW

9-10

8. LOVE PARK

21-22

4. PRECEDENT

11-12

9. HELIOSTAT

23-24

5. DESIGN OBJECTIVES

13-14

10. SUSTAINABILITY

25-26

SITE ANALYSIS TRANSIT

With its robust network of above and below grade transit infrastructure, Center City Philadelphia became the focus of my study. I identified a site on the west side of City Hall with an opportunity to connect four major transit stations, as well as capturing the bus corridor of JFK. Over 110,000 people arrive in Philadelphia via transit through this site.

Love Park

Municipal Plaza

Site Area Two - Three Penn Center Dilworth Park

City Hall

GROUND LEVEL - EXISTING

Parking Suburban Station Penn Center Concourse

Concourse City Hall Foundations

Building Basements MFL Mezzanine

CONCOURSE LEVEL - EXISTING

Commuter Platforms

KEY BUS RAIL BIKE 0’

250’

500’

1000’

Trolley Stop Loading Dock MFL Platforms

Trolley Track BSL

Trolley Stop

TRACK LEVEL - EXISTING

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Survey - MFL + BSL Mezzanine

Survey - Connection between BSL and MFL

Love Park

Parking

Loading Dock

Trolley / MFL Tracks

One of the first steps of the project was understanding the complexity deep under the streets around City Hall. I spent several days surveying the subway and concourse system to develop a 3D model of the existing conditions.

Suburban Station

THE UNDERGROUND

Underground Service Road

SITE ANALYSIS

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Concourse Under Broad St

Trolley Track

BSL City Hall Station

MFL / BSL Interchange

MFL / BSL Mezzanine

Dilworth Subway Entry

Trolley Stop

Trolley Mezzanine

Clothes Pin Sculpture

MFL Mezzanine

Concourse Entry

Commuter Tracks

MFL 15th Street Station

Three Penn Center

Two Penn Center

REVEALING THE UNDERGROUND

Looking North East

4

One Penn Center (Suburban Station)

Commuter Rail Tunnel

Viaduct (Chinese Wall)

Train Shed

Head House

SITE ANALYSIS HISTORY 1880 BROAD ST. STATION

1930 SUBURBAN STATION

An elevated viaduct once brought commuter trains into the heart of Philadelphia. A grand head house abutting City Hall designed by Frank Furness acted as a gateway to the city. The station provided a dignified way to arrive, but had its technical problems.

Trains had to pull in, then back out, which added time to the schedule. The viaduct divided this portion of the city, and earned the name "The Chinese Wall."

A solution to the problems of Broad Street Station came in the form of a new Pennsylvania Railroad HQ building atop a new subterranean rail tunnel and platforms. While the station was now more efficient, the grandeur and sense of arrival found in the old head house was now lost and replaced with cramped spaces tucked under the city streets.

Hotel

Underground Concourse

Oenn Center 2 and 3

Office Tower

Open Air Concourse

Reclaim Centre Square

1950 ED BACON CONCEPT

1960 PENN CENTER

Eventually, the Broad Street Station viaduct was demolished, and a huge swath of the city became ripe for development. Ed Bacon worked on a plan for an open air concourse that allowed pedestrians to circulate under 16th and 17th street. He focused on the arrival to City Hall, with the rhythm of light and shadow traveling under the three office towers. At the east end of the concourse, visitors rise into a new Centre Square plaza.

The Pennsylvania Railroad disregarded most of Ed Bacon’s plan, opting for an EW orientation for the office towers, and an entirely underground concourse that became more of a labyrinth than a civic experience.

"One entered the city like a god. One scuttles in now like a rat." -Vincent Scully (Describing Penn Station NYC) CHRIS HYTHA 2021

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RESEARCH

THE CASE FOR PUBLIC TRANSIT

$1,000

Automobile infrastructure has become primary to nearly everything else in our built environment. Highways tore through neighborhoods in cities, leaving public transit infrastructure underused and underfunded. Despite the dominance of cars, there are still many benefits to using alternative transportation. These benefits include cost, safety, space, and environmental impact. What happens when transportation modes other than the car are prioritized?

ANNUAL COST SEPTA COMMUTE

$8,698

AVG. ANNUAL AUTOMOBILE COST

TRANSIT FATALITIES

DEATHS PER 100M PASSENGER MILES

KEY CAR BUS RAIL 0.6

0.4

0.2

0 2013

2014

2015

2016

2017

2017

DISRUPTION IN EARTH’S CARBON DIOXIDE FLUCTUATION

BIKE - 0 lbs CO2 PER PMT

ATMOSPHERIC CO2 (PPM)

Date from NASA - https://climate.nasa.gov/evidence/

480 440 400 360 For millennia, atmospheric carbon dioxide had never been above this line

320 280 240 200 160 800,000

700,000

600,000

500,000

400,000

300,000

200,000

100,000

0

YEARS BEFORE TODAY (0=1950) TRAIN - 0.28 lbs CO2 PER PMT

C02 IN THE ATMOSPHERE AND ANNUAL EMISSIONS

420

40

400

35

380

30

360

25

340

20

320

15

300

10

280

5

260

0 1750

CAR - 0.87 lbs CO2 PER PMT

1780

1810

1840

1870

YEAR

1900

1930

1960

1990

CO2 EMISSIONS (BILLIONS OF TONS)

BUS - 0.54 lbs CO2 PER PMT

ATMOSPHERIC CO2 (PPM)

NOAA Climate.gov

2020

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INITIAL REVIEW

Preliminary bike highway axon

WINTER 2020

My initial idea for the project was to establish a pedestrian and bike highway to encourage more sustainable modes of transportation.

This highway, highlighted in orange below, was intended to make meaningful connections to transit by weaving through the city’s layers and opening up Market Street.

MAIN TAKEAWAYS The sentiment at the review was that the project is based on fundamentally flawed ideas in urban planning. It is dangerous in a city to segment and divide the street plane, and putting cyclists on an elevated highway removes them from the activity of the street. With this feedback in mind I decided to take a new approach moving forward.

Bike highway weaving under an open Market st.

View from Market Frankford Line.

Separate pedestrians and cars.

1.

2.

3.

4.

5.

6.

A typical urban street is unfriendly to pedestrians and bikes. There is a clear priority given to automobiles, which creates unsafe and unpleasant conditions for other users.

The only way to make a truly safe zone for cyclists is to entirely separate them from cars. My proposal is for an elevated bike and pedestrian highway.

A progressive urban street begins to consider cyclists with the introduction of a bike lane. In theory separating uses in this way creates a safer environment.

With the advent of a safe way to travel without a car, travel lanes below could be reduced to provide space for connections to public transit as well as rain water management features.

Unfortunately, even with a bike lanes, streets are unsafe for cyclists. There are several points of conflict such as entries to parking lots, cars turning, and trucks blocking bike lanes.

New buildings are integrated into this new elevated public realm to create more connections between above and below.

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PRECEDENT

BARCELONA SUPERBLOCK LOCATION DESIGNER DATE COMPLETE

Barcelona Salvador Rueda In Progress

The car has become primary to all other modes of transit, and this takes its toll on cities. Barcelona suffers from extreme congestion, unhealthy air, and noisy streets.

This proposal aims to solve these problems by making the car secondary.

BIKE INFRASTRUCTURE With reduced traffic speeds and smaller lane one way travel for cars, a safer space for biking is created.

BEFORE

AFTER

Barcelona is planned as a ridged grid. Currently, vehicular circulation travels between each block. Intersections contain street parking. Travel by car is encouraged in this model at the expense of pedestrians.

Nine city blocks are grouped together to create a Superblock. Heavy car traffic is directed to the perimeter, and interior roads are closed to through traffic. Interior intersections become public amenities.

CREATE GREEN CORRIDORS

IMPROVE BUS ROUTES

At the center of Superblocks streets are narrowed to give back space to the pedestrian.

As part of Barcelona’s transit overhaul, they have an ambitious plan to rethink their bus service.

PRECEDENT CENTRAL STATION LOCATION ARCHITECT DATE COMPLETE

Rotterdam, NL Benthem Crouwel March 2014

What does it mean to arrive in a city?

This project creates an intentional arrival sequence through a grand hall with a sense of civic scale and dignity. The building becomes a gateway to Rotterdam, aligning with a pedestrian friendly green axis that draws you into the city. This project is also interesting because it services nearly the exact same amount of travelers per day as my site, 110,000.

Site Plan

View of Central Station from above.

Central Station main hall.

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DESIGN OBJECTIVES

1.

Create a dignified arrival to center city with a sense of civic scale and grandeur prioritizing pedestrians over automobiles.

The Oculus NYC.

2.

Establish visual, physical, and experiential connections between the center city transit network and the activity of the city streets.

Berlin Central Station.

3.

Integrate with the surrounding context, celebrate city hall, and connect with the important axis of the Ben Franklin Parkway

City Hall Philadelphia.

ARRIVAL PLAZA New Centre Square

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SITE

PLANNING William Penn’s original plan for Philadelphia called for 5 squares. Centre square, the current site of City Hall is the only square now occupied by a large structure. Penn’s intent was for a public plaza in the heart of the city bounded by civic building. The new site plan reinterprets Centre Square as a pedestrian centric superblock and new multi-modal transit hub linking buses and rail transit.

Site plan sketch iteration 1

Site plan sketch iteration 2

Site plan sketch iteration 3

BIKE

BUS

CAR

A 0.8 mile trail circles the new Center Square to extend the recreational use of the parkway as well as provide much needed bike infrastructure in center city.

JFK is a primary bus route, made more efficient by the elimination of cars. Buses have designated loading and unloading zones throughout the superblock.

The existing one way circulation around city hall is extended to include the Municipal plaza, Love Park and the adjacent site.

SITE PLAN

New Centre Square 0’

75’

150’

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300’

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Looking west from MFL arrival plaza.

STATIONS SUBWAY / TROLLEY

On the south side of the site the commuter rail train shed reaches up into the sky with its light tectonic truss system. Here on the north side, the project sinks down to reveal the subway lines and a heavy concrete structure that is of the earth. Directly from the train platforms visitors are greeted with views out to the city, diffuse reflected natural light, and passive ventilation.

RELATION TO CONTEXT

STRUCTURE

The arched forms pick up on arches across the facade of City Hall. The image on the right demonstrates a foreground quality of the vaults. They are intended to be simple so that City Hall remains the focus.

The parabolic vault concrete structure is an inherently structural shape to provide high ceilings possible to contrast the existing low corridors. The incredible quality of reflected light (see heliostat page) was a driver of the structure. The vaulted forms catch and diffuse light to create a memorable entry experience from the subway lines.

MATERIALITY The vaults are clad in broken tile and glass to create an uneven and sparkly human scaled finish to further animate the reflected light cast down into the station.

Looking south in new BSL. station.

Secondary reflectors in plan.

Secondary reflector section

Isometric vaulted structure.

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A new commuter rail train shed creates a civic and dignified entry experience, connects above an below with views and light, and celebrates a view of city hall from the train platform. A public green lawn occupies the top of the train shed creating a multi-functional structure.

The train shed aligns with two major axis down JFK to 30th Street Station and down the Ben Franklin Parkway to the Philadelphia Museum of Art.

View from commuter rail platform.

Pedestrian circulation from station.

Market Meadow

COMMUTER RAIL

Market St.

Market Frankford Line

STATIONS

Existing Parking

Philadelphia Museum of Art

Commuter Rail Train Shed

Love Lawn

30th Street Station

Septa Bus Route

Heliostat Array

City Services

N/S SECTION PERSPECTIVE

Looking West

0’ 30’ 60’

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120’

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LOVE PARK REIMAGINED

The new green lawn looking over the parkway provides a elevated experience of the Parkway. Looking back towards City Hall, the project is intentionally left as a simple green backdrop to maintain the celebrated view of City Hall from the PMA. The three vignettes to the right demonstrate the flexibility and variety of uses envisioned for the site.

Looking NW down the Parkway.

TYPICAL DAY On a typical day, the green lawn becomes a place of pause to watch the city go by. On spring and summer days, visitors relax and picnic in the park, while taking in the view down the parkway.

SLEDDING The urban landscape of Center City Philadelphia is devoid of natural hills.

This park creates an opportunity for sledding, slip and slides, or just rolling down through the grass!

EVENTS For special events, the hill can become an assembly space that fits thousands.

Events could include shows, movie screenings, or music festivals. The open space of the lower lawn can house temporary stage / event structures.

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HELIOSTAT DAYLIGHTING

One common trait of the grand train stations of the past, like Penn Station in NYC, is access to natural daylight. On the north side of the site, southern daylight penetrates to the platforms. On the south side, an array of motorized sun reflecting panels track the sun during the day to reflect beams of natural daylight down into the subway lines.

Section perspective looking west.

SECONDARY REFLECTORS Beams of light from the primary mirror array shine down to the open face of the subway lines. To avoid unwanted glare, and to bounce light deeper, there are a series of secondary highlighted in blue above.

These suspended planes create a connection between interior and exterior. Light is bounced up into the vaulted ceiling, and the semi-transparent reflectors create diffuse illumination below.

Market St.

MFL Subway

Secondary reflector section diagram.

Light From Heliostat

Secondary Reflector

Heliostat impact on interior space - Morning

Experience of Heliostat from Street Heliostat impact on interior space - Noon

INTERIOR EFFECT

EXTERIOR EFFECT

The special collaboration programming of the office building is positioned behind the heliostat. During the morning, the heliostat acts as a screen, casting dynamic shadows on the ground. In the afternoon, the heliostat can bounce light up into the ceilings of the collaboration space.

The experience of the heliostat from the street is intended to connect pedestrians above with the rhythm of transit. The mirror panels move to illuminate either the MFL or BSL when trains arrive. From above, this rhythm is experienced, as the reflector panels move and glisten in the sun. The heliostat is not only functional, but is a public work of art to animate the arrival plaza.

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SUSTAINABILITY DIAGRAMS

The primary sustainability objective is to reduce the reliance on cars as the primary means of travel. Additionally, rainwater is not only managed, but is designed to be experienced through the site. Rocky channels cutting through the site direct rainwater to a central occupied rain garden. Grates in the plaza allow rainwater to trickle down select feature walls of the subways below to experientially connect above and below.

Occupied rain garden catchment diagram.

PASSIVE VENTILATION The open design of the subway stations allows for passive ventilation.

RAINWATER Rainwater is used experientially connect below grade to the world above.

DAYLIGHT Daylight is reflected down from the heliostat to the left, and washes down a textured stone wall to the right.

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Chris Hytha Email - Chris.hytha@gmail.com Phone - 484-753-2848 Instagram - @Hytha.cg

Drexel Architecture 2021