Based on our Group Environmental Policy, we develop buildings and create neighborhoods that help preserve the water environment through measures like effective utilization of water and replenishment of subterranean aquifers. We also preserve water resources through water conservation and effective use of water resources together with our business partners, tenant companies and stores, and customers.


We shall strive to reduce clean water and industrial water usage per base unit (of floor area) from the previous fiscal year through measures such as installing water-saving equipment in our newly constructed buildings or switching to such equipment when renovating existing buildings.

Progress in Achieving Goals

Clean water and industrial water usage per base unit (of floor area) in fiscal 2018 was 0.848 m3/m2 per year, a 6.7% increase over the previous fiscal year (0.795 m3/m2per year).
(For details on clean water and industrial water usage per base unit [of floor area], please see "Water Usage.")

Major Initiatives

Water Conservation

At our office buildings and retail facilities, the Mitsui Fudosan Group installs water-saving equipment in newly constructed buildings. We have also been switching to water-saving equipment in existing buildings when they are renovated, and are making efforts to conserve water during routine building management and operations together with our business partners, tenants, stores, and customers.

Adoption of Water-Saving Equipment

At Tokyo Midtown (Minato-ku, Tokyo), we are saving water by installing water-saving sanitary equipment, automatic faucets and similar facilities.

Large-scale renovation took place at MITSUI OUTLET PARK JAZZ DREAM NAGASHIMA (Kuwana City, Mie), and in the extended area we installed 49 ultra- water-saving toilets (flush volume 5.5 liters).

The built-for-sale and rental condominiums and built-for-sale detached housing which Mitsui Fudosan Residential sell use water-saving toilets and bathing room shower heads with a water stop button.

Use of Rainwater and Grey Water

Mitsui Fudosan aims to effectively use water resources by taking advantage of rainwater and grey water (processed wastewater) at its office buildings, retail facilities and built-for-sale condominium buildings.

Use of Rainwater and Grey Water at Tokyo Midtown Hibiya

At Tokyo Midtown Hibiya (Chiyoda-ku, Tokyo), we are planning to collect rainwater and drainage water from air-conditioners in a rainwater utilization tank (water storage capacity approximately 400m3), and after treatment use as general service water for toilet flushing and similar purposes. The plan also calls for grey water, obtained by treating kitchen wastewater, miscellaneous wastewater, and cooling tower blowdown water, to be used as general service water in the same way.

*Drainage water: Excess wastewater from humidifiers of air-conditioners, and water cooled and condensed on cooling pipes.

Letting Rainfall Reach the Ground and Preventing Rainfall Runoff

In our office buildings and retail facilities, we direct rainwater underground by utilizing water-permeable paving for parking lots, walkways, on-site roads, and external sections of the building. We also aim to preserve the water environment and prevent flooding with temporary storage tanks and flow adjustment ponds to prevent rainwater runoff in large volumes.

Water Usage

*1 Total water usage: The total of clean water, industrial water, and grey water usage.
*2 Clean water and industrial water usage: Clean water and industrial water usage includes well water usage.
*3 Amount of grey water usage: Amount of grey water usage is the total of kitchen and miscellaneous wastewater, some rain and other water processed, and recycled water purchased from the outside.

Trends in the Amount of Water Usage

Please see here (Third-party verification) for data on water usage.

Trends in Clean Water and Industrial Water Consumption

Trends in Clean Water and Industrial Water Consumption
Scope of Data Calculation

The scope of data calculation for water usage encompasses, in principle, facilities for which disclosure is required under the Act on the Rational Use of Energy. However, some facilities are excluded.

Scope of Data Calculation (Water Usage)

Business Division Type Fiscal year
2016 2017 2018
Overall No. of target facilities (facilities) 137 139 139
Total floor area (m2 5,599,861 5,938,901 6,379,120
Office buildings No. of target facilities (facilities) 75 76 70
Total floor area (m2 2,462,672 2,648,216 2,886,933
Retail facilitiesNo. of target facilities (facilities) 43 43 46
Total floor area (m2 2,851,201 2,864,433 2,973,917
HotelsNo. of target facilities (facilities) 12 12 14
Total floor area (m2 151,626 150,619 158,761
LogisticsNo. of target facilities (facilities) 3 3 3
Total floor area (m2 124,225 265,059 300,630
OtherNo. of target facilities (facilities) 4 5 6
Total floor area (m2 10,138 10,574 58,879
1.Office buildings include Tokyo Midtown (Roppongi) and Kashiwa-no-ha Smart City Gate Square shops and the office building KOIL.
2.Resort hotels are included in the scope for hotels.
3.Facilities under the control of the General Administration Department as well as each branch have been included in Other.
4.Water usage in offices is included.

Water Recycling Ratio

Trends in Water Recycling Rate (Grey Water Usage Rate)

Grey water usage rate
1.Grey water usage rate = Amount of grey water consumption/Amount of water usage x 100
2. Scope of Data Calculation is the same as for "Water Usage."