The Korea Transport Institute President, Kee Yeon Hwang, Ph.D.

Flyovers: Yes or Not?

Cheong-gye Stream Restoration in

Seoul

Dec 04, 2010

Contents

Demolishing Flyovers

Monitoring Results

Restoration Master Plan

Why restore?

In and Around Cheonggye Stream

Conclusion

I. In and Around Cheonggye Stream

Old Map of Seoul

A wash place in Cheonggye Stream

Bridge on Cheonggye Stream

(Ogansumun)

Early 20C

After War: Urban Squatter until 1970’s

Road building over the Cheonggye

After construction of the overpass

Cheonggye Expressway

Growth Pattern of Seoul

CBD in 2002

Characteristics of CBD

41 thousand

2.5million

420 thousand(11.7% of Seoul)

2 million

70%(Subway & Bus)

12 square km

73 thousand(10.2% of Seoul)

Resident

Moving Pop.

Employment

PassengerVehicle Volume

Transit Use

Area

Firms

Aging Buildings & Declining Business

2002

Beneath the Cheonggye-cheon

Low QoL

Traffic Congestion, too much through traffic

Air pollution, Noise

Relatively low land value

Loss of historic legacy

Air pollution

High-rise and dense development

Traffic Congestion

Degraded cityscape

Convenient Subway Services

6 Subway lines, 30 stations, 12 transfer stations

New Airport Rapid Railways경부고속철도

신공항철도

Declining CBD

For the past 10yr: pop. 40,000, emp. 80,000 reduced

Headquarters: 63% in Gangnam sub-center

Old buildings & narrow streets

Outdated industries

II. Why Restore?

development → conservation, auto → people, efficiency → equity

Why restore?

Paradigm shift of urban management

Safety problems of elevated expressway & covered roads

Need to restore historic legacy and water env’t

Relieving Regional Economic disparity problems in Seoul

III. RestorationMaster Plan

1. Outline

Decision of Cheonggye-cheon Restoration Project, 2002s

2002 : Decision of CRP

Cheonggye-cheon Restoration

Restoration Project in Downtown

Site Location

Site Plan

Length = 5.84km

- Upper stream (Baekwoondongcheon~Junghakcheon) : Restoration planned in long term

- Lower stream (Shindab Bridge~Jungrangcheon) : Launching an improvement plan in 2003

※ Plan of Restoring the Upper Stream and the Lower stream of

Cheonggye-cheon

Starting Restoration WorkJuly 2003

Cheonggye Expressway and Samil Expressway

in History

IV. Monitoring Results

1. Monitoring Results

O Over 30% increase of land value since July 2002

→ rents increased in spite of construction

O High demand on redevelopment sites

O Temperature drops because of reduced traffic

→ 2.3% reduction of traffics to CBD

O Reduced noise level

Traffic

Real Estate

Environ-ment

O No serious drop in LOS level

→ only 1.3% decrease on service reported

O 3.6% subway user increases, auto inflow drops

Short Term Monitoring Results

6/23(월,비)

6/25(수)

6/26(목)

6/27(금,비)

6/30(월)

7/1(화)

7/2(수)

7/3(목,비)

7/4(금)

7/7(월)

7/8(화)

7/9(수,비)

7/10(목)

7/11(금)

7/14(월)

7/15(화,비)

7/16(수)

7/17(목)

7/18(금,비)

7/21(월,비)

7/22(화,비)

7/23(수)

7/24(목,비)

7/25(금,비)

00 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.015 2.3 1.8 2.0 1.6 1.8 1.7 1.5 1.8 1.9 2.1 2.2 1.9 1.5 1.5 1.9 1.9 2.1 1.4 2.1 1.7 2.4 1.6 1.8 1.930 2.7 2.0 2.3 2.0 2.7 1.9 2.3 1.6 2.3 2.3 2.2 2.3 1.6 1.9 2.8 2.4 2.2 1.7 2.6 2.4 2.9 1.8 2.2 2.145 4.5 2.2 2.2 2.1 3.8 2.4 1.9 2.3 2.2 3.6 2.7 2.3 2.1 2.3 3.6 2.7 2.4 2.1 2.8 3.7 2.6 2.1 2.6 2.800 5.6 3.3 2.8 2.5 6.5 3.2 3.6 2.4 2.7 4.3 3.4 2.9 2.0 2.9 5.0 3.1 3.2 2.7 4.0 5.1 4.2 2.6 2.6 3.315 6.6 3.9 3.8 3.5 6.9 5.3 4.5 4.0 3.8 5.7 4.8 3.8 3.1 4.1 6.6 4.5 4.1 2.2 5.6 5.7 5.6 3.5 3.3 4.830 9.4 5.6 5.2 4.7 9.1 5.9 6.2 5.9 4.9 8.5 5.6 5.5 4.8 5.1 8.4 5.8 5.8 2.0 7.5 7.5 7.7 4.7 5.1 6.145 11.5 7.2 6.7 5.9 10.8 7.8 7.1 6.9 6.6 9.8 8.1 7.5 6.6 6.1 9.7 8.1 7.2 2.3 10.2 9.3 9.8 6.1 6.7 6.600 14.5 9.3 7.6 8.2 11.8 9.0 9.0 8.6 7.9 12.2 9.7 9.7 7.2 8.8 10.3 9.5 7.5 2.6 13.1 10.9 11.7 7.3 7.1 7.915 17.2 9.2 8.8 8.6 14.0 10.9 10.9 9.6 9.5 13.6 12.0 12.3 9.3 9.2 13.1 10.5 9.9 2.2 16.5 11.6 13.9 7.9 7.8 9.630 18.3 12.6 10.3 10.9 16.4 11.3 11.4 11.9 11.9 14.8 12.9 15.3 10.5 11.1 15.1 13.1 11.9 2.3 18.6 13.6 15.2 10.3 8.6 9.945 19.5 13.4 11.0 12.0 16.7 11.4 12.3 11.5 12.7 17.0 12.9 17.7 11.5 11.5 15.4 13.3 13.3 2.5 23.1 12.4 17.4 10.1 10.7 11.400 18.1 12.6 11.0 12.5 15.7 11.3 12.2 11.1 12.0 14.6 12.3 16.9 10.6 11.9 15.0 13.1 12.0 3.1 22.3 13.4 18.1 10.2 10.4 10.915 16.2 11.0 9.1 11.3 13.2 9.5 10.0 9.1 9.3 12.8 10.7 14.3 7.8 10.3 12.3 10.8 9.9 2.8 20.4 11.6 17.1 8.3 9.5 10.730 14.3 11.4 7.8 9.7 10.6 7.6 9.1 7.2 9.0 11.3 9.3 12.5 6.6 8.5 10.9 8.8 10.0 3.9 17.7 9.8 13.8 7.9 8.4 9.745 14.6 10.0 9.1 10.2 10.6 8.0 9.7 6.7 8.7 11.3 8.9 10.3 6.9 8.0 9.6 10.1 10.0 3.6 16.6 9.3 13.8 7.8 8.9 9.700 14.1 9.6 8.2 10.9 9.6 7.5 10.1 6.9 8.8 10.8 9.8 11.3 7.5 9.6 8.7 10.3 9.9 4.0 15.6 9.6 13.2 8.1 8.4 11.115 14.4 9.6 8.8 11.4 9.5 8.1 9.9 7.3 9.0 10.0 9.8 9.6 7.5 10.1 8.8 9.5 9.0 4.7 13.9 9.6 11.8 8.1 9.1 11.230 12.5 9.6 9.3 11.9 9.5 8.7 10.2 7.9 8.9 9.3 11.0 10.3 8.1 10.2 8.2 9.9 10.6 4.6 13.3 9.3 11.1 8.5 9.5 10.845 13.0 9.2 9.7 12.9 8.8 9.2 11.0 7.7 10.2 10.7 10.4 9.3 9.0 9.8 8.6 10.7 11.0 5.0 14.1 9.7 11.5 8.9 10.4 11.000 12.4 9.0 10.9 13.1 10.7 9.0 10.3 8.7 9.8 10.5 10.8 9.1 9.1 9.9 9.0 11.9 10.8 5.6 13.3 10.0 10.9 10.3 11.1 11.815 12.1 10.1 11.2 13.0 10.0 9.5 11.1 8.3 9.3 9.4 11.1 9.6 8.8 10.2 10.3 11.9 11.0 6.6 12.2 11.2 10.5 11.8 11.5 11.030 12.3 10.1 11.3 13.9 10.3 8.9 10.4 7.8 9.5 9.5 11.0 9.8 9.2 11.3 9.4 12.0 12.5 5.6 12.6 10.9 11.3 11.5 11.6 12.845 12.1 9.0 10.8 13.9 10.4 9.7 10.8 7.7 10.5 10.4 11.1 9.9 9.4 11.3 9.0 11.4 12.0 6.4 12.6 11.1 10.1 10.9 12.2 12.800 11.1 9.1 10.4 14.3 10.8 9.2 11.5 8.4 9.8 9.7 11.4 10.0 9.1 11.5 9.1 10.7 12.4 7.1 12.1 10.2 9.8 11.2 11.1 12.615 11.3 8.9 9.6 13.8 9.3 9.1 11.2 8.6 9.3 9.7 11.0 9.9 8.5 10.6 9.4 10.7 12.0 8.0 10.7 11.0 10.1 10.2 11.9 11.930 9.6 8.1 8.4 12.4 8.3 9.4 9.5 7.5 8.1 9.0 9.0 10.0 7.9 9.6 8.3 11.0 11.0 7.3 9.0 9.7 8.5 8.9 10.0 10.545 9.5 7.0 8.1 13.1 7.2 6.3 8.7 7.0 7.6 8.3 8.7 9.1 6.4 7.8 7.3 8.9 9.7 6.9 8.8 9.2 8.8 7.9 8.9 9.100 8.1 6.4 7.1 11.0 5.9 6.3 7.6 5.8 6.9 6.3 8.2 8.7 6.1 6.6 7.0 7.8 8.5 7.2 7.4 8.3 8.0 7.7 8.0 9.615 7.3 6.0 6.4 10.9 6.6 5.8 6.8 5.6 7.1 6.9 7.4 7.5 5.3 7.0 6.2 8.0 7.1 6.0 7.4 8.0 9.5 7.2 8.4 8.430 7.9 6.3 7.2 11.1 6.8 6.6 7.7 5.2 6.7 7.2 7.4 8.4 6.4 6.7 6.4 7.9 7.8 6.0 7.7 9.0 8.5 7.6 8.9 8.345 9.1 6.7 7.7 11.5 8.2 7.3 8.2 6.0 7.7 8.4 7.9 8.7 7.2 8.2 7.2 8.3 8.1 5.9 8.8 9.6 9.3 7.9 9.0 9.800 9.3 8.7 8.5 12.5 9.8 8.9 9.0 7.2 8.6 8.6 9.0 10.7 8.4 9.1 8.6 9.5 9.5 6.1 11.2 10.4 11.0 9.6 9.4 10.715 10.8 8.8 9.1 12.3 10.9 9.1 9.7 8.1 9.5 10.0 9.7 11.6 9.1 9.8 9.4 10.4 10.5 6.1 11.9 11.2 12.1 10.5 11.1 11.530 12.8 10.1 11.1 13.8 12.0 9.9 10.7 9.0 11.2 11.4 12.2 13.6 10.7 10.4 10.4 11.2 11.7 6.4 11.5 12.8 13.2 11.2 11.4 12.245 12.8 11.1 11.5 15.0 12.7 12.1 11.2 9.9 12.3 11.7 12.2 12.3 10.3 11.0 10.9 12.6 12.5 6.8 12.7 13.6 13.1 12.0 12.2 14.000 13.7 11.8 11.4 14.5 15.0 12.9 12.7 9.9 12.6 13.2 13.0 12.9 11.6 12.3 12.7 14.1 13.5 6.8 13.3 12.9 14.9 13.4 13.5 14.015 14.2 12.4 13.1 16.5 14.9 13.3 13.4 10.9 12.8 12.6 13.0 12.3 11.3 13.0 13.2 13.3 13.8 6.5 13.8 15.8 15.4 13.1 14.4 15.530 14.5 13.4 11.9 16.0 15.9 13.3 13.9 11.2 13.9 14.3 13.8 12.2 12.2 14.4 14.0 14.3 15.7 6.4 12.1 15.3 15.5 14.2 14.0 14.845 13.3 13.5 13.0 18.1 16.4 13.5 13.6 11.6 13.6 14.2 13.4 12.7 12.4 14.2 13.8 14.7 14.4 7.4 13.4 15.6 14.9 13.5 14.7 15.900 13.7 12.9 13.2 17.1 15.6 15.9 13.9 11.7 13.0 14.6 14.5 12.5 12.8 15.4 14.9 15.4 15.4 7.2 14.7 16.7 16.3 13.4 14.9 16.015 13.5 13.1 13.7 17.8 17.6 16.0 13.4 11.1 13.8 14.2 13.3 11.9 12.5 14.3 14.3 14.6 15.7 8.1 14.6 16.4 15.5 13.7 14.5 16.030 14.4 13.2 13.4 18.3 16.5 14.7 14.6 10.8 13.4 13.7 12.0 14.5 12.0 14.0 14.2 15.3 16.1 7.8 13.5 17.1 15.8 14.2 14.5 16.545 13.5 13.1 13.6 18.2 16.2 15.4 13.8 11.6 12.1 13.4 12.1 14.8 12.6 13.8 15.3 15.0 15.1 7.0 13.0 16.3 15.0 13.3 14.1 15.500 14.1 13.1 14.6 18.2 14.8 15.3 13.8 10.9 12.6 13.0 12.6 14.5 12.4 13.4 15.1 13.8 15.2 7.2 11.8 15.8 15.8 13.9 12.9 16.415 14.7 12.7 13.6 17.6 15.9 14.9 13.6 10.9 12.4 12.9 12.3 13.4 12.8 14.4 14.1 14.3 15.5 7.8 11.7 14.3 14.7 13.2 13.4 14.930 13.9 12.6 13.7 17.7 14.9 13.3 13.6 9.8 13.0 13.5 12.9 12.0 12.2 14.3 14.2 15.1 15.1 7.3 11.5 14.5 13.9 12.9 13.6 15.345 11.7 13.0 13.2 17.9 15.4 13.8 13.0 10.4 13.1 12.5 12.1 11.8 11.7 14.3 13.3 14.4 14.5 8.3 10.6 15.5 15.0 13.7 12.8 16.000 11.3 13.3 13.2 17.9 14.4 13.1 13.4 10.3 13.2 13.2 12.9 10.7 11.4 15.0 13.6 14.7 15.4 8.0 10.5 16.4 14.1 12.4 14.0 14.615 13.3 13.1 13.0 18.0 14.7 12.8 13.7 10.8 12.2 13.4 12.3 11.3 12.0 15.4 13.8 14.8 15.9 8.3 10.6 17.5 15.7 13.7 13.6 14.630 16.2 14.6 14.9 20.4 16.9 14.5 16.0 12.3 14.4 14.6 14.3 13.3 13.0 16.1 14.8 16.5 17.7 8.7 13.3 21.3 17.9 15.1 14.9 16.945 17.8 16.1 16.6 23.5 17.5 16.5 18.2 14.0 16.4 15.8 17.0 15.5 15.4 17.5 16.6 17.8 19.8 9.0 14.9 22.0 19.2 17.2 16.7 18.000 19.4 17.3 17.8 23.1 18.1 17.1 19.0 14.2 16.6 16.8 18.3 17.4 15.3 19.3 17.9 18.6 21.4 8.7 15.1 23.5 20.6 17.2 17.5 20.215 17.5 16.2 17.4 23.6 17.0 16.5 18.3 14.2 16.3 17.0 17.5 16.9 15.9 19.8 17.3 18.1 21.7 8.3 15.2 23.3 19.7 16.4 18.4 21.430 19.8 15.8 17.2 22.2 16.9 17.0 18.9 14.3 16.0 16.7 17.5 17.2 15.0 18.8 17.2 19.5 22.4 7.5 16.0 22.7 21.2 15.5 18.5 20.945 17.1 16.1 15.5 22.6 16.4 14.9 18.1 12.5 16.1 15.6 16.9 15.5 14.3 18.3 16.4 18.0 21.8 6.7 13.9 21.5 18.5 14.3 19.2 20.800 15.7 13.3 12.9 19.7 15.5 12.4 15.5 11.4 14.6 13.9 15.5 13.4 12.9 17.5 14.2 15.7 19.9 5.9 12.5 20.0 18.5 11.2 16.9 19.515 13.7 11.7 12.3 18.3 13.3 12.3 13.8 10.3 12.2 12.5 13.1 11.0 12.2 15.7 11.9 15.3 18.6 7.1 10.5 16.6 16.2 10.7 15.6 18.330 11.3 11.0 11.5 14.7 11.4 11.2 13.0 9.2 11.6 11.7 12.5 9.7 10.3 14.9 10.4 15.0 16.7 5.6 9.2 15.4 14.9 10.2 13.3 17.445 10.0 9.0 10.4 13.9 10.5 10.1 10.5 7.9 10.7 10.0 10.7 8.0 9.5 13.7 8.9 12.6 15.8 4.8 8.3 12.7 14.4 7.4 11.7 15.700 8.6 8.6 8.3 11.9 8.8 9.2 9.6 7.0 8.9 8.6 8.6 6.6 8.3 11.9 7.7 11.4 14.8 5.3 6.7 11.2 12.6 5.9 10.9 15.115 7.6 6.7 7.7 10.9 8.4 7.9 8.6 6.5 8.4 7.8 8.1 5.9 6.6 10.8 6.6 12.1 12.8 5.7 6.5 10.0 11.2 5.1 10.1 13.730 7.0 7.5 7.9 10.3 7.4 8.1 8.1 6.6 8.3 7.9 8.6 5.8 6.7 10.9 6.5 11.6 11.8 5.1 6.7 9.9 10.5 5.9 10.7 12.245 5.8 7.5 7.0 8.8 6.9 7.1 8.0 5.5 7.7 6.3 7.9 5.3 6.3 9.8 5.9 10.9 13.0 6.2 6.5 8.2 10.5 5.9 12.0 11.6

0~4% 17~23% 23~100%

21

날짜시간

20

6

7

8

15

16

9

10

The Rate of under 10km/h links in Seoul

17

11

12

18

19

13

14

범 례

4~7% 7~10% 10~13% 13~17%

Traffic Delay: before & after Restoration work

Ø CBD Volume decrease 10.3% in 2004, 29.9% in 2005

Ø No Significant Change from June 2003. to Dec. 2003

Ø Morning Peak : 17~18 Km/h

Ø Afternoon Peak : 12 Km/h

Traffic Volume & Speed Changes

0.0

5.0

10.0

15.0

20.0

25.0

1월 2월 3월 4월 5월 6월 7월 8월 9월 10월 11월 12월

도심평균속도(오후)

A.M. Peak Speed Ave. P.M. Peak Speed Ave.

Average speed(a.m.) Average speed(p.m.)

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

Km/h Km/h

Ø Bus 3.2% increase

Ø Subway

- Seoul : 6% increase

- CBD : 13.7% increase

Mass Transit Passenger Change

지하철이용승객 현황

3,000

3,500

4,000

4,500

5,000

5,500

6,000

1월 2월 3월 4월 5월 6월 7월 8월 9월 10월 11월 12월

(천명:인)

2003년 2004년

대중교통 체계 개편

청계천 복원공사

<bus> <subway>

Bus Passengers Subway Passengers

CRP

Reform Bus System

Reform Bus System

CRP

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

Year

Year

1,000 person1,000 person

2. Before & After

Before 1950 1960-1970

1980-2005

present

1950

Before

After

After

Before

After

Before

3. Positive Externalities

Dismantling Flyovers & Open Sky

Turning car lanes into open plaza

Oct. 2009

May 1 2004 Opened

→ Restrained Traffic Flow

→ Pedestrian Square

Before After

Reform of Seoul Plaza

숭례문 광장

서울역

광화문광장

Seoul

Plaza

Urban Stream Renaissance

River Renaissance

around the country

Ichon Master Plan NanpoJamwon Master Plan

Youido Master Plan

V. Flyover Demolition

Construction of Flyover in Seoul

Increase capacity at the intersection (20)

Overpass rail line (23)

Highway construction (17)

Overcome surface gap (33)

Background of Demolition

Obstructing the view of cityscape

Discontinuation of Bus Rapid Transit

(BRT)

Background of Demolition

Safety management request

Queue spillback from the bottleneck

Background of Demolition

Drastic lane change

Weaving movement at the foot of the

flyover

Demolition Plan

▶ Maintaining necessary flyovers for basic traffic function

▶ Demolish flyovers primarily which are

- not worsening congestion even after demolition

- unsafe for being constructed before 90s,

- obstructing the view of cityscape

- widening slum area

Demolition Plan

- in 2009 : 2 flyovers- in 2010 : 5 flyovers- after 2011 : 9 flyovers

Dismantling Flyover

2009201020112012

2

1

3

6

4

5

78

10

9

11

12

13

15

14

16

Traffic Effect After Demolition

No.

of

Int.

Peak

Hour

Before After Variation

Volume

(pcu/hr)

Delay

(sec/pcu)

Volume

(pcu/hr)

Delay

(sec/pcu)

Volume

(pcu/hr)

Delay

(sec/pcu)

1

A.M. 6,988 104.9 8,866 134.8 △1,350 △29.9

P.M. 6,937 93.1 8,794 36.3 △1,543 ▼56.8

2

A.M. 9,154 147.3 8,819 71.1 ▼335 ▼76.2

P.M. 8,734 101.3 8,743 64.7 △9 ▼36.6

Surveyed volume and intersection delay after demolition

No. of

Int.

Delay (sec/veh) Variation

(sec/veh)

No. of

Int.

Delay (sec/veh)Variation

Before After Before After

3 146.6 155.9 △9.3 10 181.5 169.2 ▼12.3

4 135.6 153.1 △17.5 11 - - -

5 39.8 64.9 △25.1 12 96.2 117.6 △21.4

6 15.4 83.1 △67.7 13 115.1 155.6 △40.5

7 134.4 136.7 △2.30 14 125.1 184.0 △58.9

8 - - - 15 - - -

9 - - - 16 - - -

Estimated Intersection Delay by traffic flow model

Traffic Effect After Demolition

After

Cityscape : Before and After

Before

After

Cityscape : Before and After

Before

VI. Conclusion

▶ Activated flyover construction before 1990

- Increased capacity at the intersections

▶ Paradigm shift of urban management

- Green growth, Cityscape protection

▶ Demolition flyover in Seoul

- Cheonggye-cheon and 2 flyovers over intersection

- Very positive opinions among citizens

Conclusion

Thank You

Before CRPAfter CRP