Washington State University

Organic Farming Systems and Nutrient Management

Biosolids Management

Biosolids are stabilized solids from municipal wastewater treatment that meet federal criteria for land application. They are a good source of plant nutrients (particularly nitrogen, phosphorus, sulfur, and zinc). We have done research on nutrient availability from biosolids in dryland wheat rotations in eastern Washington and irrigated forage grasses in western Washington. We also have a biosolids and compost demonstration garden at WSU Puyallup. We have been partners in a national biosolids study designed to develop simple methods to predict the availability of nitrogen from different types of biosolids in different environments, and in a study assessing the fate of flame retardants in biosolids.

Photo produce grown with biosolids

Worksheet for calculating biosolids application in agriculture:


Publications - Extension and Management Bulletins:

Worksheet for calculating biosolids application in agriculture. (online pdf). Cogger, C.G. and D.M. Sullivan. 2007. PNW0511-E. Washington State University Cooperative Extension.

Fertilizing with Biosolids (online pdf). Sullivan, D.M. 2007. PNW 508-E. Oregon State University Extension Service.

Biosolids management guidelines for Washington State.  (online pdf, or Request hard copy). Cogger, C.G., D.M. Sullivan, C.L. Henry, and K. P. Dorsey.   2000.  Washington State Dept. Ecology Pub. #93-80. 

Publications - Peer-reviewed Journals:

Biosolids Applications to Tall Fescue Have Long-Term Influence on Soil Nitrogen, Carbon, and Phosphorus.  (request pdf e-copy)  Cogger, C.G., A.I. Bary, E.A. Myhre, and A.M. Fortuna. 2013.  J. Environ. Qual. 42:516–522.

Long-Term Crop and Soil Response to Biosolids Applications in Dryland Wheat.  (request pdf e-copy) Cogger, C. G., A. I. Bary, A. C. Kennedy, and A.M. Fortuna. 2013. J. Environ. Qual. 42:1872-1880.  

Estimating Nitrogen Availability of Heat-Dried Biosolids.  (request pdf e-copy)  Cogger, C.G., A.I. Bary, and E.A. Myhre.  2011.  Applied Environ. Soil Sci.  Vol. 2011, Article ID 190731, 7p.  doi:10.1155/2011/190731

Dryland Winter Wheat Yield, Grain Protein, and Soil Nitrogen Responses to Fertilizer and Biosolids Applications. (request pdf e-copy)  Koenig, R.T., C.G. Cogger, and A.I. Bary.  2011.  Applied Environ. Soil Sci. Vol. 2011, Article ID 925462, 9p. doi:10.1155/2011/925462.

Chrysanthemum production in composted and noncomposted organic waste substrates fertilized with nitrogen at two rates using surface and subirrigation. (request pdf e-copy). Krucker, M., R.L. Hummel, and C. Cogger. 2010. HortSci. 45:1695-1701.

Predicting biosolids application rates for dryland wheat across a range of Northwest climate zones. (request pdf e-copy). Sullivan, D., Bary, A., Cogger, C. and Shearin, T. 2009. Commun. Soil Sci. Plant Anal. 40:1770-1789.

Biosolids recycling: Nitrogen management and soil ecology. (request pdf e-copy). Cogger, C.G., T.A. Forge, and G.H. Neilsen, 2006. Can. J. Soil Sci. 86:613-620

Biosolids processing effects on first and second year available N. (request pdf e-copy). Cogger, C.G., Bary, A.I., D.M. Sullivan, and E.A. Myhre. 2004. Soil Sci. Soc. Am. J. 68:162-167.

Decomposition and plant-available nitrogen in biosolids: Laboratory studies, field studies, and computer simulation. (request pdf e-copy). Gilmour, J.T., C.G. Cogger, L.W. Jacobs, G.K. Evanylo, and D.M. Sullivan. 2003. J. Environ. Qual. 32:1498-1507.

Seven years of biosolids vs. inorganic nitrogen applications to tall fescue. (request pdf e-copy). Cogger, C.G., A.I Bary, S.C. Fransen, and D.M. Sullivan. 2001. J. Environ. Qual. 30:2188-2194.

Nitrogen recovery from heat-dried and dewatered biosolids applied to forage grasses. (request pdf e-copy). Cogger, C.G., D.M. Sullivan, A.I. Bary, and S.C. Fransen. 1999. J. Environ. Qual. 28:754-759.

Matching plant-available nitrogen from biosolids with dryland wheat needs. (online pdf). Cogger, C.G., D.M. Sullivan, A.I. Bary, and J.A. Kropf. 1998. J. Prod. Agric. 11:41-47.

Biosolids and dairy manure as nitrogen sources for prairiegrass on a poorly drained soil. (request pdf e-copy). Sullivan, D.M., S.C. Fransen, C.G. Cogger, and A.I. Bary. 1997. J. Prod. Agric. 10:589-596.

Publications - Other Reports:

Summary Report. A survey of Skagit County residents: Opinions about local reuse and recycling of biosolids compostOR Executive SummaryYoungquist, C. P. and J. R. Goldberger.  Washington State University.  2013.  As part of a Washington State University (WSU) research project funded by the Town of La Conner, WA, a mail survey of Skagit County residents was conducted in 2013. The objectives were (1) to gain a better understanding of residents' attitudes, opinions, and knowledge about the use of "Class A" biosolids on agricultural land and in the community; and (2) to explore potential correlations between attitudes about biosolids and the demographics and lifestyle choices of respondents. The results provide valuable insight into Skagit County residents’ attitudes, opinions, and knowledge about local waste management, local agricultural use of "Class A" biosolids, and the use of biosolids-based fertilizers on food crops. This information will be useful to local governments, community groups, waste management personnel, farmers, and researchers.

Creating High Value Potting Media from Composts Made with Biosolids and Carbon-Rich Organic Wastes (online - pdf). Hummel, R., C. Cogger, A. Bary, and B. Riley. 2009. WSU

Agronomic biosolids application rates for dryland wheat across a range of Northwest climate zones. (online - pdf). Sullivan, D.M., Bary, A.I., and Cogger, C.G. 2007. Proc. Western Nutrient Mgmt. Conf, 7: 188-193. Salt Lake City, UT.

Estimating nitrogen availability from biosolids. (online - pdf). Cogger, C.G., A.I. Bary, D.M. Sullivan, and E.A. Myhre. 2003. NW Biosolids Management Assoc. Seattle, WA. Short research note.

Using Biosolids as Growing Media in Greenhouse Production of Chrysanthemums. (online - html). Hummel, R., Krucker, M., and Cogger, C. 2003. , WSU.