Water Resources

The Production & Environment Subcommittee manages the SUBARU Group’s water usage at each site, and both the total amount and amount used per unit of sales are maintained at a constant level.
The share of each water source in the total freshwater consumption at the SUBARU Group is as follows: industrial water 67%, tap water 27%, and groundwater 6%. As we are well aware of the risks involved in using the valuable resource of fresh water, we carefully monitor water consumption by conducting water risk assessments at major locations. Although the current assessment results show that the water risk is not high, we will continue to regularly assess our water risk levels and work to reduce water consumption in order to ensure a continuous water supply.

Water Risk Assessment

The SUBARU Group uses a third-party expert to implement water risk assessments* to ensure the sustainable use of water. These assessments estimated, among other things, the water supply and demand risk in the river basins in which the production bases are located, the probability of water-related disasters occurring, and the impact on public health and ecosystems on a five-point scale. Risk assessments utilized the most severe RCP8.5 climate change scenario adopted by the IPCC. These assessments showed that water risk at the Gunma Plant, Utsunomiya Plant, and Subaru of Indiana Automotive, Inc. is generally evaluated as moderate or lower.

Gunma Plant and Subaru of Indiana Automotive, Inc.

According to an assessment in FYE March 2017, the water supply and demand risk at the Gunma Plant and Subaru of Indiana Automotive, Inc., both of which are automobile manufacturing bases, is moderate. It is expected that the current risk level will be maintained for the medium to long term, even when the impact of climate change is taken into account. No biodiversity conservation areas are identified at the lower reaches of the rivers. The vulnerability to water pollution is low.

Utsunomiya Plant

According to an assessment in FYE March 2018, the water supply and demand risk at the Utsunomiya Plant, which is our base for aerospace manufacturing, is moderate. This risk level is expected to drop in the future as an increase in the river flow rate and decrease in water demand are likely to take place. The plant is not located in an area at high risk of flood inundation or landslides. No biodiversity conservation areas or habitats for rare aquatic life are identified in the areas within 10 km downstream from the site. Going forward, we will continue to accurately monitor our water risk based on the assessments, ensure optimum water consumption in relation to local water demand, and help conserve the environment along the river.

* Reference databases

WRI Aqueduct water risk atlas, WWF-DEG Water Risk Filter, PREVIEW Global Risk Data Platform, Climate Change Knowledge Portal, Integrated Biodiversity Assessment Tool, National Land Numerical Information: Possible Inundation Area Data and Sediment Disaster Hazard Area Data (Ministry of Land, Infrastructure, Transport and Tourism), NCD-VfU-GIZ Water Scarcity Valuation Tool (Version 1.0), Costing Nature/Water World, (Only for Gunma Plant and Utsunomiya Plant)

Water Consumption

The total amount used is monitored and compiled for each location, and reported and verified at biannual meetings. Necessary measures are then taken as appropriate.

Water Consumption

Scope:

SUBARU:

Gunma Plant, Tokyo Office, Utsunomiya Plant, Handa Plant, Handa West Plant

Group companies in Japan:

Yusoki Kogyo K.K., Fuji Machinery Co., Ltd., Ichitan Co., Ltd., Kiryu Industrial Co., Ltd., Subaru Logistics Co., Ltd.

Overseas Group companies:

Subaru of Indiana Automotive, Inc., Subaru of America, Inc., Subaru Canada, Inc., Subaru Research & Development, Inc.

FYE March 2023 Water Consumption by Source (Thousands of m³)

Scope:

Japan:

Gunma Plant, Tokyo Office, Utsunomiya Plant, Handa Plant, Handa West Plant, Yusoki Kogyo K.K., Fuji Machinery Co., Ltd., Ichitan Co., Ltd., Kiryu Industrial Co., Ltd., Subaru Logistics Co., Ltd.

North America:

Subaru of Indiana Automotive, Inc., Subaru of America, Inc., Subaru Canada, Inc., Subaru Research & Development, Inc.

*

Subaru of America, Inc, Subaru Canada, Inc and Subaru Research & Development, Inc were added to the scope from FYE March 2023.

Water Reuse

Utsunomiya Plant

The Utsunomiya Plant has introduced a surface treatment facility equipped with an ion-exchange water recycling system that converts wastewater into pure water. In FYE March 2023, 23,389 m³ (29.7%) of the total of 78,781 m³ of water used in the surface treatment facility was recycled and utilized at the plant as washing water for the surface treatment facility.

Representative Surface Treatment Wastewater Processing and Recycling

Water Discharge

Gunma Plant

In the Gunma region, wastewater from our plants is treated, water quality is checked in an oil-water separation tank, and it is discharged into rivers, where it eventually merges into the Tone River. Appropriate wastewater treatment is provided to ensure the water from the Tone River is safe during use for agricultural and domestic purposes in the downstream areas.

Utsunomiya Plant

In the Utsunomiya area, after treating wastewater from surface treatment processes we discharge it into the sewer system, and discharge rainwater and cooling water into the river after checking its quality in the final water quality monitoring tank. In addition, we dispose of wastewater from the painting process in the Handa area as industrial waste, and treat domestic wastewater in septic tanks prior to discharging it into Kinuura Port and the Agui River.

Utsunomiya Area Wastewater Treatment Process