Before getting quotes or designing facilities, you need to know how much compostable waste is being generated. Here are some averages by category (per student, per employee, etc.) and other ideas to get you started.

1. Estimating volumes
for composting

2. You’re thinking about diverting food waste and
other organics from disposal to composting.
The big question is ...
where to begin?

3. When not offered as part of a
municipal service, commercial
hauling and composting services
are usually based on fees
charged by the ton.

4. Before you can get quotes from
contractors and other service
providers, before anyone can talk
collection strategies or space
requirements for your own facility,
you’ve got to get a handle on
generation volumes and convert
those volumes to tons.

5. Your goal is to determine how
many tons of compostables are
being generated each year,
whether a municipality,
household, college, factory or
business park.

6. Then you can begin the planning process
and start to gather cost estimates.

7. There are a number of routes available for determining annual
volumes of organic wastes. Each has advantages and
disadvantages.
Here are some ideas
to get your project
started:

8. Develop estimates
based on published
norms and averages.
ROUTE 1

9. The largest component of the
MSW stream is compostable:
• 14.9% food
• 26.6% paper and cardboard
• 6.2% wood
• 13.3% yard trimmings
≥ 61%
(NOTE: Some non-identified organics currently
classified as textiles, plastics and other, plus gypsum
board, are also compostable using a high-rate process.
As much as 70% of the global waste stream is compostable.)
SOURCE: https://www.epa.gov/smm/advancing-sustainable-materials-management-facts-and-figures

10. Solid waste
generation
rates for
households,
schools,
hotels, etc.
SOURCE: http://www1.nyc.gov/assets/oec/technical-manual/14_Solid_Waste_2014.pdf

11. SOURCE:
https://www.refed.com/downloads/
ReFED_Technical_Appendix.pdf
More solid waste
generation rate
estimates

12. 10 gal = 20 lbs.
20-32 gal = 60 lbs.
45-64 gal = 120 lbs.
96 gal = 180 lbs.
Contact your waste hauler or city/county
solid waste division for specific sizes or
weight limits for your community.
SOURCE: https://www.recology.com/recology-
cleanscapes/bothell/your-three-carts/
Maximum cart
weight examples

13. Multiply the size of your
container by these weights:
• 1 cubic yard of food waste is 1,070 pounds
or about .5 tons
• 1 cubic yard of mixed paper is 875 pounds
or .44 tons
• A 40 cubic yard roll-off filled with flattened
corrugated cardboard weighs 1 ton (50
pounds per cubic yard)
Contact your waste hauler or city/county solid
waste division for specific container sizes and
weight limits for your community.
SOURCE:
https://www.des.nh.gov/organization/divisions/waste/
swmb/css/documents/vol-to-weight-conversion.doc
Weights by the cubic yard

14. Calculation example - households
500 households, each generating (1) 10 gallon/20 pound
organics cart per week
20 lbs. per week x 52 weeks =
1,040 lbs/year/household
divided by 2000 lbs. per ton =
.52 tons per year (TPY)
per household
.52 tons x 500 households
= 260 tons of organics generated
by those 500 households per year

15. Calculation example - college
1 college of 35,000 students generating 1 pound per student
per week =
35,000 lbs. per week x 52 weeks = 1.82 million lbs. per year
/ 2000 lbs. per ton = 910 TPY
910 TPY x 61% (organic fraction of the MSW stream)
= 555.1 tons
of organics generated
by the college per year

16. Calculation example – fast food
1 restaurant with 16 employees generating 200 lbs. per
employee per week =
16 x 200 = 3,200 lbs. per week
3,200 lbs. per week x 52 weeks
= 166,400 lbs. per year
/ 2000 lbs. per ton
= 83.2 tons per year (TPY)
83.2 TPY x 61% (organic fraction
of the total MSW stream)
= 50.8 tons of organics
generated by the restaurant per year

17. PROS: Fast, cheap, easy
CONS: If your community, office, school, etc. varies significantly
from the average, results will not be representative.
RECOMMENDED FOR: Low volume generators (the total
volume of any “error” will be a small amount). For
everyone else, rough estimates only.
ROUTE
1

18. DIY waste audit
ROUTE 2

19. 1. Take statistically representative,
random samples
2. Sort and weigh
3. Calculate annual tonnage

20. SOURCE: 2009 UHBristol Clinical Audit Team – Version 3. This resource discusses clinical audits, but
suggests a number of sampling methods to improve randomization and reduce sampling bias.
What’s a representative sample?

21. 1. Take statistically representative,
random samples
2. Sort and weigh
3. Calculate annual tonnage

22. • Separate the sample from the
total waste stream.
• Sort the contents (paper, plastic,
metal, food, etc.).
• Weigh the results in each waste
category if conducting a full
waste stream audit. Otherwise,
just weigh the
compostables and
average the results
to develop
generation rates
per audit unit, i.e.,
per person, cart, classroom, etc.

23. Common compostables*:
• Food scraps, culls and plate waste
• Paper and cardboard, including dirty and waxed
• Grass, yard waste and other vegetation
• Unpainted/untreated wood and gypsum board
If intended for processing at a modern,
high-rate facility you may also include*:
• Meat, bones, dairy
• Compostable plastics
• DAF sludge and other food processing
by-products
• Municipal drinking water and
wastewater treatment sludge
*Verify acceptance with composter

24. 1. Take statistically representative,
random samples
2. Sort and weigh
3. Calculate annual tonnage

25. Calculation example
If the sample representing one week’s
worth of garbage resulted in 10 pounds
of separated organics:
10 pounds x 52 weeks per year
= 520 pounds per year
520 pounds/2000 pounds per ton
= .26 tons of organics per year

26. DIY audit postscript
Sometimes, a local college or university
will have a professor, student, or class
looking for a research project.
Your waste audit might be a perfect for
their needs. This win-win can provide you
with quality data for a low-to-no
investment in time or dollars.
Check with departments related to
engineering, environment, hospitality,
health, etc.

27. PROS: Requires a little time, but not much money. Can be
carried out by one person or as a group project.
CONS: Is only as accurate as the volunteers. Training to help
sorters identify compostables recommended.
RECOMMENDED FOR: Almost anyone.
NOT RECOMMENDED IF: There are safety concerns, like
toxic constituents.
ROUTE
2

28. Professional
waste audits
ROUTE 3

29. If the waste stream is
too large or too complex for a
do-it-yourself project, you
may have to call in the
Big Guns.

30. For municipalities and other high-volume
waste generators requiring more exact
figures than sampling or calculation
can provide, or when the waste
stream contains toxins or other
components that make DIY
assessments inadvisable,
a professional waste
audit or waste
characterization
study may be the best route.

31. Professionals may charge by the hour or
by the contract. But if you are in an area
where tipping fees for composting are less
than for disposal, the audit may pay
for itself many times over in the
form of reduced
costs for waste
management
services.

32. PROS: Can be the most accurate method.
Requires no training, volunteer mobilization
or outreach program development.
CONS: Will require a budget.
RECOMMENDED FOR: Sizeable and/or
toxic waste streams where the expense of
professional expertise and equipment is
warranted.
ROUTE
3

33. Some online tools for DIY waste audits:
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Inc. All rights reserved.
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