Indoor Water Conservation

What is Indoor Water Conservation?

Indoor water conservation refers to building operations, occupant behaviors and water-efficient fixtures and appliances that help to reduce overall water consumption in a building. The commercial and industrial building sector uses large quantities of water, with office buildings representing 9% of water use.[1] Figure 1 shows that the three most significant areas for potential water savings in office buildings are restrooms, cooling and heating, and landscape irrigation.[2]

Figure 1- End used of water in Commercial Office Buildings. (Source: US EPA WaterSense).

New Jersey receives ample average rainfall of 45 inches per year, and the state’s geology supports the storage of large quantities of groundwater and surface water reservoirs. However, ongoing conservation efforts and water-efficient equipment upgrades can reduce the risk of water shortages and reduce costs associated with increasing population growth, aging water infrastructure, and climate change impacts such as droughts.[3]

Indoor water conservation generally addresses water use reductions in four areas:[4]

• Reducing water losses associated with leaks.
• Increasing the water efficiency of fixtures, equipment, systems, and processes.
• Educating staff and occupants about water conservation to encourage water-saving behaviors.
• Reusing onsite wastewater for irrigation and non-potable uses.

How to Implement Indoor Water Conservation

Implementing indoor water conservation depends on the functions of the building but typically includes:[5]

• Installing water meters and sub-meters and leak detection sensors to track water usage, find and fix leaks and equipment failures, and identify opportunities for water savings (see Smart Meters, and Smart Sensors and Controls).
• Specifying low-flow, WaterSense certified fixtures such as toilets, showers, faucets, and aerators, and energy-efficient, EnergyStar certified appliances, such as dishwashers and clothes washers, that also conserve water (see Energy Star Equipment and Plug Load).
• Properly maintaining HVAC systems to minimize water used for cooling equipment, eliminating single-pass cooling, and optimizing boiler and steam systems by reusing excess steam.[6]
• Minimizing irrigation or recovering wastewater for irrigation and uses that do not require potable water such as toilet and urinal flushing, and cooling tower make-up water (see Water Efficient Landscaping, Rain Barrels and Cisterns, On-Site Alternative Water Reuse).
• Educating staff and occupants on water conservation efforts and procedures to ensure the proper use of water-saving equipment (e.g., instructions for dual flush toilets) and to help identify water saving opportunities (e.g., hotlines for leak reporting).[7]

Example

US EPA WaterSense for Commercial Buildings – Case Studies

The US EPA WaterSense program provides case studies from across the country and within the commercial and industrial sector that document water efficiency efforts and best practices outlined in WaterSense at Work: Best Management Practices for Commercial and Institutional Facilities including detailed descriptions of the project and associated water, energy and cost savings.

Benefits

Indoor water conservation reduces the strain on natural water resources and ensures future water supplies.[8] Water saving fixtures and appliances save money on water and energy bills without sacrificing performance, the latter savings due to the significant amount of energy often used to heat water.[9] For example, WaterSense certified fixtures and appliances save 20% more water than standard products.[10] EnergyStar certified commercial dishwashers use 40% less water and energy than standard models.[11] Indoor water conservation can also reduce the costs and the amount of energy required to treat, pump, and transport water and wastewater.[12]

Costs

The rising cost over the last decade of water and wastewater services can make minor investments in water conservation strategies and technologies cost-effective based on the savings alone from reduced water bills.[13] Factoring in savings from reduced energy bills further reduces payback periods.

Resiliency

Indoor water conservation enhances resiliency by reducing impacts from droughts and other instances of water scarcity. Water use reductions also decrease the reliance and stress on the entire municipal water infrastructure including groundwater pumping, and water and wastewater treatment and distribution, reducing the likelihood of system overload and failure.[14]

[1] US EPA WaterSense. 2018. Types of Facilities. https://www.epa.gov/watersense/types-facilities (accessed Oct 25, 2018).

[2] US EPA WaterSense. 2012. Saving Water in Office Buildings. https://www.epa.gov/sites/production/files/2017-01/documents/ws-commercial-factsheet-offices.pdf (accessed Oct 25, 2018).

[3] New Jersey Department of Environmental Protection, 2017, New Jersey Water Supply Plan 2017-2022: 484p, http://www.nj.gov/dep/watersupply/wsp.html (accessed Oct 25, 2018).

[4] US EPA WaterSense. 2012. WaterSense at Work: Best Management Practices for Commercial and Institutional Facilities. https://www.epa.gov/sites/production/files/2017-02/documents/watersense-at-work_final_508c3.pdf   (accessed Oct 26, 2018).

[5] US EPA WaterSense. 2018. Types of Facilities. https://www.epa.gov/watersense/types-facilities (accessed Oct 25, 2018).

[6] US EPA. 2017. Water Management and Best Practices at EPA. https://www.epa.gov/greeningepa/water-management-plans-and-best-practices-epa (accessed Oct 25, 2018).

[7] Joseph Bourg. 2016. Water Conservation. Whole Building Design Guide – A Program of the National Institute of Building Science. https://www.wbdg.org/resources/water-conservation (accessed Oct 26, 2018).

[8] NJ DEP Division of Water Supply and Geoscience. 2018. The Case for Water Conservation in New Jersey. https://www.state.nj.us/dep/watersupply/conserve.htm (accessed Oct 26, 2018).

[9] US EPA WaterSense. 2012. Best Management Practices for Commercial and Institutional Facilities.

https://www.epa.gov/sites/production/files/2017-01/documents/ws-commercial-factsheet-general-ci.pdf  (accessed Oct 26, 2018).

[10] US EPA WaterSense. 2017. Statistics and Facts: WaterSense and Water Savings. https://www.epa.gov/watersense/statistics-and-facts (accessed Oct 26, 2018).

[11] US DOE EnergyStar. 2018. Dishwashers. https://www.energystar.gov/products/appliances/dishwashers (accessed Oct 26, 2018).

[12] NJ DEP Division of Water Supply and Geoscience. 2018. The Case for Water Conservation in New Jersey. https://www.state.nj.us/dep/watersupply/conserve.htm (accessed Oct 26, 2018).

[13] Joseph Bourg. 2016. Water Conservation. Whole Building Design Guide – A Program of the National Institute of Building Science. https://www.wbdg.org/resources/water-conservation (accessed Oct 26, 2018).

[14] Ibid.