Approved by the Energy, Environment, and Water Policy Committee On January 24, 2024
Approved by the Public Policy Committee on May 1, 2024
Adopted by the Board of Direction on July 18, 2024
Policy
The American Society of Civil Engineers (ASCE) supports treated wastewater and graywater reuse as a water supply source for the beneficial uses of industries and communities, including agricultural, industrial, and municipal uses. ASCE recommends the following:
- Support for the “One Water” concept that looks to break down the regulatory, policy, and organizational silos that limit the safe and efficient reclamation and reuse of wastewater and stormwater.
- Encouraging the use of treated wastewater, stormwater, and graywater as part of plans to develop or expand water supplies where legally, technically, and economically feasible to do so and be protective of public health, safety, and welfare.
- Encouraging the reuse of non-potable water when it can be provided cost effectively.
- Providing funding, such as federal or state loans or grants, to local utilities for implementation of treated wastewater, stormwater, and graywater reuse.
- Updating or establishing regulations, building codes, and requirements by state and local agencies that promote water reuse projects, educating the public to the benefits of water reuse, and specifically limiting discharges near sensitive water bodies.
- Furthering research and development into treatment and expanded applications of water reuse.
Issue
Sound water management consists of a variety of strategies to maximize the sustainable use of limited water resources. Water management strategies include water conservation, as well as wastewater and stormwater water reclamation and reuse. The demand for water is increasing, driven by population growth and urbanization. Simultaneously, many water supply sources are dwindling due to drought or excessive withdrawals. According to the Environmental Protection Agency (EPA), publicly owned treatment works (POTWs) treat thirty-two billion gallons of wastewater every day. Some of this wastewater could be reused where legally, technically, and economically feasible. Regulatory reform for water reuse should be an integral part of a water supply strategy. Public health and environmental requirements on the use and treatment of these waters must ensure water quality standards appropriate for the use.
Indirect potable reuse (IPR), where treated wastewater is used to replenish surface water and groundwater supply sources is permitted and practiced in several states. Direct potable reuse (DPR) where treated wastewater becomes an influent source to a drinking water treatment facility, is now permitted in two states and others are considering it.
Graywater generated from water use in bathtubs, showers, sinks, washing machines, and dishwashers accounts for a large portion of the outflow produced in homes. With lower concentrations of organic material and other contaminants found in wastewater, graywater systems can be a viable source of non-potable water where building codes allow for separated graywater systems.
The use of treated wastewater for irrigation is presently practiced in many locations where legally permitted. Increasing public acceptance of wastewater reclamation through education in many communities can make it a viable component of a community’s water supply portfolio.
Rationale
Water reuse refers to the reclamation of domestic and industrial wastewater that has been treated to specific standards set by state, federal and local agencies and beneficially utilized for industrial, commercial, agricultural, and municipal purposes. Water reuse has been successfully applied in many areas of the country. Proven treatment technology is readily available, and in many cases has been fully implemented to provide safe, reliable water supplies for a variety of uses.
In a recent Value of Water campaign polling exercise, 69 percent of Americans were concerned about their future water supply. ASCE recognizes the need for water recycling through the reuse of treated wastewater for agricultural and landscape irrigation, industrial processes, replenishing water supply sources, and public water supply. Water reuse can offer resource and financial savings, and wastewater treatment can be tailored to meet the water quality requirements of the desired reuse application.
ASCE Policy Statement 332
First Approved in 1987