Preventing Water Pollution and Effective Use of Water Resources
Water Resource Conservation
Conservation Activities from Three Perspectives
At Shimizu, we work on conservation of water resources from three perspectives.
|Office activities||Reduce waste, use recycled water|
|Job sites||Use the technology we possess to improve efficiency, reuse water, and manage wastewater discharge|
|R&D||Research water reuse and treatment technology|
Response on Conservation of Water Resources and Water Risks at Job Sites
The amount of water needed at a job site differs substantially, depending on the surrounding environment, type and size of building, construction method, and other factors.
We have begun a trial in setting quantitative goals for the amount of water withdrawn and wastewater discharged (usage volume, reduction in volume, etc.), in addition to the goals of reducing violations of environmental laws and regulations on water and mishaps.
In addition to working to reduce the unnecessary use of water at each job site, we take the information on local water risks (typhoon season, rainfall amount, volume of water withdrawn and discharged, restrictions on water quality, etc.) generated from committee meetings held at the time of design and at the time of a quote being generated, and confirm this information in a committee meeting before beginning construction. We then formulate a plan for appropriate water usage and execute it. In this water usage plan, we prioritize reducing the volume of water withdrawn and discharged, working to recycle and reuse water, and manage the quality of wastewater.
After beginning construction, a simple treatment water tank (notch tank) or a large turbid water treatment plant is installed, depending on the amount of water usage and project scale, and daily management and key point management is performed according to voluntary management standards that meet or exceed legally mandated standards. Various divisions in the company also perform checks through onsite patrols and audits, and strict management is performed until the project is delivered to the customer. This contributes to conservation of local water resources.
Effective Use of Water Resources
The job sites in each area are production locations in the construction industry. Water used in living and water used in construction is therefore withdrawn and discharged locally.
The methods for water withdrawal and discharge at construction sites and the countermeasures implemented in neighboring areas are provided in the form of a prepared chart of standards and operating manual used for the entire company.
The status of water resource withdrawal and discharge and the management plans for each business-related category are as shown in the table below:
|Category||Status of Main Uses of Water Resources||Water Resource Management Plan|
|Job Sites (in Japan)||Water withdrawal (municipal potable water, groundwater, surface river water*)||
As indicated below, management is performed according to the specific characteristics of the site and surrounding environment at each site.
|Water discharge (off-site water treatment)||
|Job Sites (Overseas)||Same as in Japan||Nearly the same as in Japan|
|Offices in Japan & Overseas||Water use: Municipal potable water||Water used for daily activities||
|Wastewater: off-site water treatment discharge||Wastewater from kitchen, washing/flushing, and rainwater|
Shimizu obtains the proper permits for using groundwater, surface/river water, etc. in areas where municipal potable water cannot be used.
Shimizu engages in systematic efforts to improve water use efficiency and mitigate or prevent a negative impact. Below are several examples of specific initiatives.
|Water sprinkling to prevent dust||In cases where construction involves dismantling a building and requires sprinkling water to prevent dust, we reduced tap water usage by reusing the water that had collected in the underground spring pit during dismantling.|
|Reuse of Processing Water in Underground Pits||In cases where contaminated soil was excavated in underground pits and carried out, we initially used tap water to clean the pit after excavation and transport vehicle tires, but reduced water usage by treating water with water treatment equipment and recycling the treated water confirmed to meet the proper standards.|
|Use of Recycled Water in Tunnel Construction, etc.||We reuse water that wells up in the tunnel as construction water by using a turbid water treatment plant within the job site on projects involving tunnel construction and other types of construction as well, thereby recycling and reducing water use.|
Qualitative Goals for Effective Water Use (Linked to Biodiversity)
As part of the environmental policy of the Shimizu Group, we aim to “minimize our environmental footprint in business activities” and “create and restore the environment” and have identified biodiversity as a key component of these goals. Reducing the impact of construction on the environment as far as possible is fundamental to our policy. Moreover, one of the initiatives in construction activities in the Shimizu Biodiversity Guidelines is to identify the impact on the environment during construction and work to eliminate or reduce any additional impact. We also track the number of serious environmental incidents as a KPI (key performance indicator) to manage our goals for water resources and water pollution. We have included measures against water pollution as one of the items in the Job Site Environmental Key Point Management Chart that is created before construction begins and use this in managing construction wastewater at all construction sites.
External Collaboration on Effective Use of Water Resources
Shimizu promotes joint research on water treatment, participates in water treatment projects, builds water treatment infrastructure, etc. in collaboration with external stakeholders.
Joint Research on Water Treatment
- Development of a new water treatment system that uses biotechnology (bio-focus project)
- Comprehensive technological development project by the Ministry of Construction that began in fiscal 1985 and implemented over five years
- Aqua Renaissance 90 Plan
- This plan was implemented over six years, from 1985 to 1990, as a project by MITI (Ministry of International Trade and Industry) and NEDO (New Energy and Industrial Technology Development Organization) entitled “Development of complex methane gas manufacturing equipment with a high-performance separation membrane.” The goal of the project was to develop a system that combined biological treatment with membrane treatment.
- Development of labor-saving technology for tunnel wastewater treatment
- R&D on tunnel wastewater (mining wastewater) treatment technology by the Metal Mining Agency of Japan (now JOGMEC) and a special commission (1993–1998)
- NEDO/RITE project to develop technology for remediation of contaminated soil, etc.
- Technology for treating groundwater contaminated by trichloroethylene was developed in a project that extended from 1995 to 2001.
This was the first experimental verification of bio augmentation in Japan.
- Joint research with the Japan Atomic Energy Agency
- Research was performed on modeling groundwater flow and technology to control high-pressure spring water.
The research made effective use of limited data to explore ways to evaluate groundwater flow characteristics which included reverse analysis to enable efficient projection of the spatial distribution of uneven flow characteristics.
Various grouting methods (crack reinforcement in the dam base, etc.) and materials were also considered for controlling the high-pressure spring water that emerges from deep underground.
- Joint research by NEDO and Shinshu University
- Use of groundwater for heat pump air conditioning
Groundwater was used as a heat source to reduce the amount of energy used for air conditioning. The efficiency and reliability of the heat pump depending on the temperature of the groundwater was verified.
- Joint research by Japan Cooperation Center Petroleum (JCCP), the Oman Ministry of Oil & Gas, and relevant professors and academics
- Created a new water resource through research on the nature of water containing oil and development of treatment technology
This research verified the technology for using the large volume of produced water from exploratory drilling for crude oil as a water resource. (The groundwater pumped up along with the crude oil was previously designated as wastewater and was returned to the ground.)
Participation in Water Treatment Projects
- August 2007 to March 2008: Council on Competitiveness-Nippon (COCN) project on technology for the effective use of water treatment and water resources
- This project explored issues in overseas development, a water business model for overseas, and framework for proceeding with development
(Team members: The University of Tokyo, Hitachi Plant Services Co., Ltd., Hitachi, Ltd., Toray Industries, Inc., Shimizu Corporation, Kajima Corporation, Toshiba Corporation, Mitsubishi Electric Corporation, Fuji Electric Co., Ltd., and NGK)
- August 2009 onward: Global Water Recycling and Reuse System Association, JAPAN (GWRA)
- GWRA was established in November 2008 at the suggestion of COCN (45 corporate participants as of March 2010). Activities are conducted by the Project Committee (that conducts market research, etc.) and the Planning and Strategy Committee (plans projects, etc.)
- September 2009 to February 2010: Survey and research committee on the effective use of water resources and the water resource supply business, Japan Industry Association
- This committee conducted surveys and research on how to enter the water business market overseas (desalinization of ocean water and recycled sewage water)
- April 2010 onward: Mekong-Japan Industry and Government Dialog sponsored by the Ministry of Economy, Trade & Industry for industry, government, and academic organizations
- Project members participated with the goal of industry participation in the business of infrastructure development, etc. and regional development in the Mekong region.
- April 2014 onward: Development of technology for washing dioxin-contaminated soil in Vietnam
- Shimizu worked together with CTET, a research organization in the Vietnamese Ministry of National Defense on researching applications for soil washing technology at Bien Hoa Airport and other locations.
- 2014 onward: Building rain gardens
- Rain gardens were use at Kyoto University of Advanced Science, Yokohama Nomura Building, and other locations to control rainwater run-off from the premises. We conducted a survey on the effectiveness, etc.
Building Water Treatment Infrastructure
- Pahang-Selangor Raw Water Transfer Tunnel (Malaysia)
- At 44.6 km long, this is Southeast Asia’s longest water conduit tunnel. It was built to supply 1.89 million m3 of water per day to the Kuala Lumpur greater metropolitan area and Selangor State from neighboring Pahang State to provide a stable supply of water for daily life and commercial use.
This project was part of Greater KL, a national project to transform the greater metropolitan area into a global international city and provide an engine for economic growth. It involved over 100 local staff members, 1,000 workers from 12 countries, and a construction period of 1,800 days. It was completed in May 2014.
- Project for produced water containing oil
- In order to create a new water resource from this produced water, Shimizu worked with JCCP (Japan Cooperation Center Petroleum), Sultan Qaboos University, the Oman Ministry of Oil & Gas, and others on developing highly efficient produced water treatment technology that is simple and can be used for general purposes.
- Sewer Systems and Treatment Facilities in Malaysia and Vietnam
- Shimizu built four sewage treatment facilities, one slurry treatment facility, roughly 5.4 km of a main sewage line, and 17.3 km of a sewage pipeline network for the area surrounding Kuala Lumpur. We also built a sewage treatment facility in Ho Chi Minh. Both projects were completed in 2009.
- Effective use of water in office buildings
- Shimizu promoted use of water-saving sanitary fixtures and actively worked to make it possible to use gray water by treating it with a membrane separation method in the Shimizu head office building.
We received the LEED-NC Gold Award for our efforts. LEED (Leadership in Energy & Environmental Design) is an international system of certification for evaluating the environmental performance of buildings.
Compliance on Water Quality and Water Resources
Shimizu complies with laws and regulations, ordinances, and other rules concerning the use and discharge of water resources in construction.
Preventing Water Pollution
We work hard to prevent water pollution during construction by providing a Manual on Preventing Water Pollution at Job Sites, conduct e-learning courses, and holding meetings for the construction managers at each branch. We also implement various initiatives during Water Pollution Preventing Awareness Month in June of each year.
Business Activities in Water-stressed Areas Overseas
We manage the water risks of business activities (building construction and civil engineering) in water-stressed regions, utilizing the World Resources Institute’s (WRI’s) Water Risk Atlas.
Shimizu’s business activities in regions identified to be potentially exposed to water stress are listed in the table below.
Of the overseas job sites scored according to five levels of water risk, none were in areas of “extremely high risk.” There were total of 13 job sites in areas of “high” risk, located in China, India, and Mexico, accounting for 12% of all overseas job sites (less than 1% of all job sites, when including job sites in Japan).
In the future, we will continue to target strict risk management in advance and respond to restrictions in water management as we carry out business activities in areas of high water risk.
Produced Water Project: Aiming to Solve the Three Largest Environmental Challenges in Middle Eastern Oil Producing Countries by Creating New Water Resources
Produced water from oil production refers to the groundwater that wells up during oil drilling. The amount of water produced ranges from three to five times the amount of oil produced. In Oman, there are areas where one oil field generates 200,000 m3 of produced water a day, more than half of the potable water supply for Muscat, the capital of the country.
Produced water contains oil and hazardous heavy metals that are extremely difficult to remove. Treatment is difficult and nearly all of the produced water is returned, unused, to the subterranean mine, at present. In order to create a new water resource from this produced water, Shimizu working with JCCP (Japan Cooperation Center Petroleum), Sultan Qaboos University, the Oman Ministry of Oil & Gas, and others on developing highly efficient produced water treatment technology that is simple and can be used for general purposes. This treatment of produced water has already reached the level of the standard needed for water used in irrigation.
Shimizu is also working on an oil well waste treatment/usage system for the sludge and other waste pumped up along with produced water. We have developed an irrigation and seaweed farming system and are performing experimental verification aimed at commercialization. We are working to solve the three greatest environmental problems in Oman and other Middle Eastern oil producing countries: Produced water, oil well waste, and water resource depletion.
Responding to Abnormal Weather
At each job site, we develop a response plan and stockpile emergency materials based on the specific characteristics of the surrounding environment and region. The general estimate for the cost of responding to water-related risks (stockpiling of emergency materials, etc.) is around 56 million yen a year for job sites in Japan.