The first-ever analysis of resource recovery by United States (U.S.) water utilities shows significant progress in using biosolids and generating energy, but large growth opportunities in water reuse and nutrient capture.
Led by the Water Environment Federation, the ReNEW Water Project utilises data from national and state databases, publications, and a utility survey, which represents about 25 per cent of municipal wastewater flow and about 20 per cent of biosolids produced in the U.S.
“With each passing year, more water utilities are engaging in resource recovery both for the environmental benefits and the economic opportunities that emerge,” said Eileen O’Neill, Executive Director of WEF. “Establishing metrics on resource recovery is crucial to moving into a more circular economy that ensures sustainability for future generations. WEF is proud to launch the ReNEW Water Project to monitor and accelerate the rate of water reuse, nutrient capture, and energy generation by facilities.”
The data showed the following levels of recovery of available resources:
- Water reuse of 2.2 billion gallons (8.32 billion litres) per year for a seven per cent recovery rate. This water primarily is for non-potable uses such as irrigation and groundwater replenishment
- Biosolids of 3.4 million dry metric tons per year for a 51 per cent recovery rate. Recovered biosolids are land applied for fertiliser, composted, and used for other beneficial purposes
- Phosphorus of 68,220 dry metric tons per year for a 21 per cent recovery rate. Phosphorus is used in land-applied biosolids, captured in fertiliser, and recycled water for irrigation
- Nitrogen of 172,400 dry metric tons per year for an 11 per cent recovery rate. This nitrogen is mostly used in land-applied biosolids and recycled water for irrigation
- Energy of 350 megawatts of biogas per year for a 41 per cent recovery rate. Facilities produce biogas, recover heat from the treatment process, and generate electricity
WEF launched the ReNEW Water Project to create a bold, aspirational, and public call to action to accelerate resource recovery, and the NEW stands for nutrients, energy, and water. The first step was establishing the baseline for current resource recovery practices. Later this fall, WEF will announce goals for water utilities to increase resource recovery from baseline levels. New data will be collected on a biannual basis and expanded to Canadian water facilities.
Aging infrastructure, population pressures, climate change, and funding limitations strain water resources and call for sustainable management solutions. Wastewater treatment plants cannot operate merely as disposal facilities any longer. Instead, resource recovery must become a cornerstone of facility operation, producing water for reuse, recovering nutrients, and reducing fossil fuel consumption by using the energy in wastewater. To help guide utilities and sector decision makers, WEF offers Resource Recovery Roadmaps.
Supporting organisations for the ReNEW Water Project include the Association of Clean Water Administrators (ACWA), National Association of Clean Water Agencies (NACWA), The Water Research Foundation (WRF), and WateReuse Association, as well as Réseau Environnement in Quebec, Canada.