Pioneering the Future of the City - The Realities and Prospects of the Iidabashi Station East Area Redevelopment Project

Taken from the Tokyo Metropolitan Government website

In the Iidabashi Station East District, a large-scale Type 1 Urban Redevelopment Project is underway covering an area of approximately 0.7 ha. The project is a redevelopment project centered on a complex facility with 26 stories above ground and 2 below and a height of approximately 130 meters, with a total floor area of approximately 46,565 square meters. The total project cost is approximately 36.7 billion yen, and construction is scheduled for completion in 2026.

Building Structure and Floor Plan by Use

Adapted from Shimizu Corporation website

The high-rise building, the centerpiece of the redevelopment project, will feature a vertical mixed-use layout with commercial and utility facilities on the lower floors, offices on the middle and upper floors, and residences on the upper floors. The office floors, in particular, are designed to accommodate modern work styles with an efficient loan area of over 1,400m2 on each floor.

The specific floor configuration is as follows:

• B2F to B1F: Parking and equipment-related facilities
• 1st floor: commercial facilities, entrance, through passage
• 2nd - 3rd floors: Commercial facilities, utility facilities
• 4th to 15th floors: Office floors
• 16th to 26th floors: Residential (approximately 180 units planned)

Of particular note is the through passageway on the first floor, which will serve as a new flow line connecting the JR and Tokyo Metro Tozai Line stations, and will be a public space that will be open to traffic 24 hours a day within the site. This will greatly improve the efficiency of travel between the east and west sides of the station.

Specifics of the Urban Infrastructure Improvement

In addition to the construction of the building, the project will also involve the concurrent development of the surrounding urban infrastructure. Specifically:

1. Road widening and installation of utility poles

   • Special ward road No. 288: Widening to 8.0m wide
   • Special ward road No. 290: Widening to 11.0m wide
   • Both roads will be pole-free to improve the scenery and ensure safety during disasters.

2. Development of public plaza

   • Construct a new public plaza with an area of approximately 296 m2
   • Creating a space in front of the East Exit of JR Iidabashi Station to serve as a hub of interaction between people.

3. Underground pedestrian network

   • Direct connection to the Tokyo Metro Tozai Line underground concourse
   • Establishment of an underground plaza of approximately 500 m2 to serve as a temporary evacuation site in the event of a disaster

4. Reinforcement of barrier-free flow lines

   • New elevators and escalators have been installed to facilitate vertical movement between the ground and underground levels.
   • Introduction of a universal design that is easy for everyone to use

Project Background and Schedule

This project has been realized after a long period of study and preparation:

• December 2006: Establishment of a committee to consider the future of the Iidabashi 3-chome-7 area
• June 2010: Iidabashi Station East Area Urban Redevelopment Council established
• July 2013: Iidabashi Station East Area Urban Redevelopment Preparatory Association established
• June 2021: Urban planning decision made
• October 2022: Iidabashi Station East Area Urban Redevelopment Association established
• FY2023: Approval of rights conversion plan and start of new construction
• FY2026: Construction to be completed

Construction is currently underway, with the building's foundation and frame work to be completed in fiscal 2026.

Specific measures to solve local issues

Measures to alleviate station congestion

Significant congestion occurs at the east exit of Iidabashi Station, especially near the Tokyo Metro Tozai Line entrance during the morning and evening rush hours. This redevelopment project is taking several measures to address this problem.

1. Expansion of underground entrances and exits

   • Expansion of the current Tozai Line entrance/exit by approximately 1.5 times
   • Expanding the concourse space by approximately 300 m2 to provide more space for passengers to stay

2. New above-ground-underground connection lines

   • Multiple vertical flow lines (escalators, elevators)
   • Design to disperse the flow of people during peak hours

3. Pedestrian simulation analysis

   • Predictive analysis of pedestrian flow before and after redevelopment
   • Identify areas of congestion and incorporate into design

Enhancement of Disaster Prevention Functions

This district is positioned as a "Regional Disaster Prevention Hub" in the Chiyoda Ward Disaster Prevention Plan, and ensuring safety in the event of a disaster is an important issue.

1. Establishment of Temporary Accommodation Facilities

   • The underground plaza is designed as a temporary accommodation facility in the event of a disaster.
   • Space designed to accommodate approximately 500 people
   • Secure emergency power supply for 72 hours

2. Installation of a disaster prevention stockpile warehouse

   • Disaster prevention stockpile warehouse of approx. 200 m2 is installed in the building
   • Stockpiles drinking water, emergency food, simple toilets, etc.

3. Establishment of information dissemination base

   • Disaster information dissemination and collection center on the first floor
   • Digital signage and wireless LAN access points installed

Environmental Consideration and Sustainability

Environmental considerations are also an important theme of this project. Specifically:

1. Greening plan

   • Secured a greening ratio of approximately 20% within the site
   • Three-dimensional greening plan including rooftop garden and wall greening
   • Greening rate exceeding the standard of the Tokyo Metropolitan Government's "Greening Plan System

2. Energy conservation measures

   • Aim for energy-saving performance equivalent to ZEB Ready (Nearly ZEB)
   • Installation of photovoltaic panels (approx. 50 kW)
   • Use of the latest high-efficiency equipment

3. Rainwater utilization system

   • Rainwater collected on the rooftop is reused as gray water
   • Utilized for toilet flushing and irrigation of plantings

Cooperation with Surrounding Areas and Ripple Effects

Relationship with the Comprehensive Redevelopment Plan for the Iidabashi Station Area

This project is positioned as part of the "Iidabashi Station Area Infrastructure Development Plan. Several redevelopment projects are underway in the Iidabashi Station area, and comprehensive urban development is being promoted in coordination with these projects.

1. Cooperation with the Iidabashi Station Central District

   • Development of a pedestrian network with the adjacent "Iidabashi Station Central District" across Mejiro-dori
   • Study of deck-level connection

2. Synergy with the Fujimi 2-chome No. 3 District Redevelopment

   • Improvement of visitor circulation with the Fujimi 2-chome No. 3 District Redevelopment (21-story mixed-use facility) underway at the west exit of the station
   • Integrated revitalization of the station area through both the East and West projects

3. Coordination with JR Iidabashi Station Improvement Project

   • Improvement of entrances and exits in conjunction with the relocation of the platform at JR Iidabashi Station
   • Coordination to improve circulation between east and west sides of the station

Economic ripple effect and job creation

The redevelopment project is expected to have a ripple effect on the local economy:

1. Job creation effects

   • Temporary employment due to construction work: approx. 2,000 people
   • Permanent employment after opening of facilities: approx. 1,500 (offices, commercial facilities, etc.)

2. Stimulation of local economy

   • New consumption generated by commercial facilities: approx. 3 billion yen per year
   • Peripheral consumption by office workers: approx. 1 billion yen per year
   • Increase in property and other tax revenues: approx. 500 million yen per year

Tenant composition and public facility planning

Zoning plan for commercial facilities

Approximately 5,000 m2 of commercial facilities are planned for the lower floors (1st to 3rd floors) of the complex.

1. 1st floor: Food, beverage and retail zone

   • Highly convenient store configuration utilizing the location directly connected to the station
   • Daily-use stores such as cafes, bakeries, and convenience stores
   • Store layout with an open facade along the through passage

2. 2nd floor: Service and clinic zone

   • Medical clinic mall (internal medicine, dentistry, ophthalmology, etc.)
   • Financial institutions, lifestyle support services

3. 3rd floor: Food, Beverage and Culture Zone

   • Restaurants, cafes
   • Bookstores, culture schools, etc.

Planned introduction of public utility facilities

The following functions are planned for public interest facilities

1. Childcare support facilities

   • Licensed daycare center with an area of approximately 500 m2 (capacity of 60 children)
   • Temporary childcare facility

2. Community space

   • Multi-purpose space for community residents, workers, and visitors
   • Variable layout to accommodate events and seminars

3. Administrative service counter

   • Chiyoda Ward administrative service counter (issuing certificates, etc.)

Office and Residential Features

1. Office Specifications

   • Efficient layout with column-free space (approx. 1,400 m2/floor)
   • Ceiling height 2.8m, OA floor 100mm
   • Smart office support utilizing the latest IoT technology
   • BCP compliant (72-hour emergency power generation function)

2. Residential units

   • Approximately 180 urban residential units (1LDK-3LDK)
   • Located on the 16th and higher floors to ensure excellent views
   • Residents-only lounge and fitness space
   • High earthquake resistance through the use of seismic isolation

Innovative approach to redevelopment

Utilization of Digital Technology

The project proactively incorporates advanced digital technologies:

1. Full use of BIM (Building Information Modeling)

   • Integrated management through BIM from design to construction and operation
   • Easy-to-understand explanations to residents and right holders using 3D models

2. Smart building

   • Automatic control of air conditioning and lighting by sensor network
   • Enhanced security with facial recognition system
   • Reservation and use of various facilities through mobile apps

3. Digital twin construction

   • Real-time digitization of building and facility operating status
   • Reduction of maintenance costs through predictive maintenance

Square management through public-private partnership

1. Establishment of area management organization

   • Establishment of an area management organization derived from the redevelopment association
   • Public-private partnership involving facility owners, tenants, and government

2. Square utilization program

   • Seasonal events (spring cherry blossom festival, summer Noryosai, etc.)
   • Weekday lunchtime market
   • Cultural and artistic events on holidays

3. Revenue return model

   • Secure independent financial resources through revenue-generating projects at the plaza (opening of kiosks, etc.)
   • Establishment of a system for allocating funds to maintenance and management costs

Summary - Urban evolution brought about by the Iidabashi Station East District Redevelopment

The Iidabashi Station East District Redevelopment Project is an advanced project that goes beyond mere building renewal to both upgrade urban functions and improve the quality of people's lives. The project aims to create a sustainable urban space with the convenience of a direct connection to the station, enhanced disaster prevention functions, and environmental friendliness.

Particularly noteworthy is the improvement of circulation through the development of a pedestrian network above and below ground. This is expected to have the effect of not only easing congestion around the station but also revitalizing the entire Iidabashi area. The complex, which will integrate office, residential, commercial, and utility facilities, will serve as a base to support a variety of urban activities in an integrated manner.

The project, which is steadily progressing toward completion in 2026, has the potential to become a new landmark for Iidabashi and a model case for redevelopment in the city center. We will continue to contribute to sustainable urban development with an eye on the future of the city.