Biosolids Facts
for more information go to the Library PageWhat are Biosolids?
Biosolids are the nutrient-rich organic product of wastewater treatment.
A beneficial resource, biosolids contain essential plant nutrient and
organic matter and are recycled as a fertilizer and soil amendment.
Wastewater Treatment
Wastewater treatment processes are taken right out of nature's recipe
book. In streams and lakes natural aeration helps to purify the water
while microorganisms break down solids. Wastewater treatment uses the
same idea; the liquid portion is treated and returned to streams, lakes,
or oceans, and the solids are further processed into stable organic
material, called biosolids.
Everyone contributes directly or indirectly to biosolids. Both businesses and households, whether connected to sewer systems or on septic tanks, generate biosolids. Today, modern treatment processes and strict controls on discharges to sewers contribute to high quality, recyclable biosolids.
Landscaping
Biosolids composted with sawdust, wood chips, yard clippings, or crop
residues make excellent mulches and topsoils for horticultural and landscaping
purposes. Many professional landscapers use composted biosolids for
landscaping new homes and businesses. Home gardeners also find composted
biosolids to be an excellent addition to planting beds and gardens.
Forestry
Biosolids improve forest productivity, increase growth of hybrid poplars
and enhance the aesthetic value of Christmas trees. Where biosolids
have been used, the trees grow faster than those living in unfertilized
soils. Wildlife populations often increase in these areas because the
understory vegetation is more abundant.
Land Reclamation
Severely disturbed soils can be reclaimed through the addition of biosolids
to replace lost topsoil. Biosolids have been used successfully to reclaim
surface strip mines, large construction sites, parks, wetlands and landfills.
Biosolids improve soil fertility and stability, aiding revegetation
and decreasing erosion.
Agriculture
Biosolids recycled in agriculture provide essential plant nutrients
such as nitrogen, phosphorus, and zinc for healthy crops. Biosolids
promote root growth by improving soil tilth, enhancing moisture retention,
and encouraging earthworms. Biosolids supply organic matter and often
improve yields, both of which help control soil erosion. Biosolids recycling
can play an important role in soil fertilization and conservation.
Environment
Recycling biosolids is good for the environment. Organic matter has
been recycled for centuries to improve soil fertility and productivity.
When properly applied and managed, biosolids can:
- provide essential plant nutrients
- improve soil structure and tilth
- add organic matter
- enhance moisture retention
- reduce soil erosion
Biosolids recycling is regulated and encouraged by the United States Environmental Protection Agency and state and local authorities. Research and years of recycling experience have demonstrated that properly managed land application of biosolids is environmentally safe.
