U.S. Biosolids
Biosolids are recycled products:
regulated, treated, & tested wastewater solids
used as fertilizers & soil amendments.
Learn more from these biosolids resources.
National 2018 Data
Confidence in these data is:
MODERATE
Click to download.
Definitions
Terms used on this website and in data sets are defined & discussed here.
2004 Data
The first National Survey on Biosolids Regulation, Quality, End Use and Disposal was completed in 2007, reporting 2004 data. Those reports are available here:
Biosolids composting in Arizona. Photo courtesy of Synagro.
Biosolids land application in Illinois. Photo courtesy of Fox Metro.
Loading out biosolids at the Grasslands facility in upstate New York. Photo courtesy of Casella.
Biosolids dryer in Newport, TN. Photo courtesy of Rob Lantz, SSR.
Anaerobic digester at Honolulu’s biosolids treatment & pelletizing facility. Photo courtesy of Synagro.
Biosolids composting at Emerald Coast in Florida. Photo courtesy of BioCycle.
Land applying biosolids in Oklahoma. Photo courtesy of Oklahoma City.
Click on chart to enlarge.
Wheat crop grown with Loop biosolids from King County (Seattle). Photo courtesy Loop (King County, WA)
National Statistics Dashboard
Where are high-quality biosolids available? These are biosolids products — composts, pellet fertilizers, etc. — that are locally and regionally available for anyone for use in landscaping, gardens, horticulture, agriculture, and tree plantings.
See the map: https://bit.ly/3j3Mx9y.
Data compiled & map produced by Bill Toffey, Effluential Synergies & former Executive Director of MABA.
Please send updates and corrections to wtoffey(at)effluentialsynergies.com.
A few fun facts from national 2018 data:
DC Water’s Blue Plains facility. Photo courtesy of DC Water.
National Biosolids Summary
In addition to the summary provided here, there is a low-resolution set of slides (PDF format) that provide details and charts about the nationwide data. Click the gray button below. A copy of the slides (ppt format. high resolution) is available from the downloads page.
● Over half (53%) of wastewater solids (sewage sludges) are treated and recycled to soils as biosolids fertilizers and soil amendments, according to representative data from 2018 compiled by the National Biosolids Data Project (NBDP).
● The other 47% of U.S. wastewater solids are placed in landfills or incinerated.
● NBDP chose 2018 as the data year for this nationwide compilation because 2018 is representative of biosolids management in the late 2010s and early 2020s, after sewage sludge incinerator (SSI) regulations and before changes due to PFAS.
● The 2018 data are comparable to the 2004 data compiled by the same team (NEBRA et al., 2007), and several trends are clear, showing relatively small percentage (%) changes:
o The percent of beneficial use of biosolids increased, from 49% in 2004 (not including stored biosolids) to 53% in 2018.
o ~5% more 2018 biosolids were Class A, and about ~5% less were Class B.
o The percent of biosolids used for land reclamation decreased ~1%, while agricultural use increased ~1%.
o The percent (%) of incineration decreased ~1%, while surface disposal increased ~1%.
● Who manages biosolids for water resource recovery facilities (WRRFs)? About half of WRRFs report that biosolids are managed by WRRF staff, while the other half have contracted haulers and land appliers.
● What crops are grown with biosolids? Mostly corn for animal feed and energy, followed by hay/grass/forage. Other popular crops for biosolids fertilization are wheat and other grains, followed by Class A EQ products widely used on turfgrass (lawns, erosion control, golf courses, landscaping).
● How much storage capacity do WRRF’s have? According to the NBDP survey of WRRFs, the majority have almost no storage capacity or time for holding biosolids if needed, and most of the remaining facilities only have up to 6 months’ storage capacity.
● According to the NBDP survey of WRRFs, average nutrient levels in U.S. biosolids are:
o Class A: 3.4% Nitrogen, 2.3% Phosphorus
o Class B: 4.8% Nitrogen, 2.0% Phosphorus
● The average cost per wet ton paid by WRRFs for biosolids use or disposal in 2018 varied, as follows:
o $49 for composting
o $58.25 for landfill disposal
o $62 for land application
o $95.30 for incineration.
● When identifying the greatest pressures on biosolids management in 2018, WRRFs showed most concern about rising costs and future outlets for biosolids. State biosolids regulators and WRRFs said that public involvement, contaminants, and the hassles of recycling – including declining nearby farmland – were significant pressures.
● Most state regulatory agencies have significantly fewer resources – staff time – dedicated to biosolids oversight in 2018 compared to 2004.
● The average U.S. resident accounts for 37 pounds (6.8 kg) of biosolids used or disposed of each year. You gave enough to make 37 pounds of finished biosolids / solids / sludge.
Mine reclamation with biosolids in Pennsylvania, before and after. Photo courtesy of Bill Toffey/MABA.
Field stacking bulk biosolids in Wisconsin. Photo courtesy of Appleton, WI.
Click on chart to enlarge.