148 East 2nd Street North Vancouver, BC V7L 1C3
Canada p: 604-984-9730 f: 604-984-3563
northshorerecycling.ca
Backyard Composting Undervalued New Data Reveals Underestimated Diversion Rates
and Collection Cost Savings
Prepared by: Christine Pinkham
Project Coordinator
and
Elizabeth Leboe Community Programs Coordinator
North Shore Recycling Program
May, 2011
Backyard Composting Undervalued
Page ii
© 2011, North Shore Recycling Program. All Rights Reserved.
Backyard Composting Undervalued
Page iii
Summary
Backyard composting is undervalued; it is far more important than we thought. Each year in North and West
Vancouver, between 8,398 and 10,514 tonnes of single-family organic waste is generated but never placed
curbside for municipal collection and disposal. This rivals the curbside Yard Trimmings collection service in
diversion tonnages (10,638 tonnes), but minus all the associated municipal costs (~$2,100,000) and environmental
implications of an industrialized collection and composting system. Without backyard composting, North Shore
municipalities would require an additional 1,500 truck trips to the transfer station, for which they would be
charged $874,227 in tipping fees each year. Factoring backyard composting into the equation increases the single-
family diversion rate from 59.5% to 67.2%, approaching our Regional target of 70%. Over the past five years,
backyard composting has saved the municipalities about $3.5 million in tipping fees alone.
Study Context and Methods
The North Shore Recycling Program (NSRP) administers the residential curbside recycling program and provides
waste reduction education in North and West Vancouver, BC, member municipalities of Metro Vancouver (MV).
This study was initiated to address municipal and regional data gaps in the calculation of organic waste diversion
rates attributed to backyard composting. Three studies were run concurrently to provide an accurate average
annual per-household diversion rate through backyard composting and to evaluate compost bin alternatives:
1. Study 1: Organic Waste Diversion
2. Study 2: Suitability of the Mega Composter
3. Study 3: Suitability of the Green Cone Food Waste Digester
Twenty-five volunteer composting households were recruited to participate in this project. After receiving
personalized Compost Coaching in January 2010, volunteers weighed their composted household organic waste
and yard trimmings for the remainder of the year (11 months).
Suitability of Alternative Composter and Digester
Neither the Mega Composter nor the Green Cone presents a viable alternative to the compost bin currently
available to North Shore residents. Capacity issues are better addressed by emphasizing the benefits of a multi-
bin system. The Green Cone could be considered as a component in an onsite organics management system that
includes backyard composting, but only for qualified North Shore residents and only once a support program is in
place.
Organic Waste Diversion Measurements
Twenty-five volunteer households diverted over seven tonnes of organic waste from curbside pickup in 2010. The
average study household kept 452 kilograms (kg) off the curb during the year. We calibrated an earlier baseline
estimate from households composting without any support or training to derive an estimate of 361 kg/hh/year.
Backyard Composting Undervalued
Page iv
Measured (with training)
Calibrated Baseline (no training)
Total Organics 452 kg 361 kg
Weights kept of the curb per household per year due to backyard composting.
Unlike other studies in our region, our research measured the combined total of organic waste composted from
both inside and outside the single-family home. Results for the indoor component were on par with the “non-
contact” extrapolation in the Township of Langley’s 2010 study. Results for the outdoor component matched
Seattle Public Utilities’ calculated findings from the 1990s. Our overall results are 20-30% higher than the National
Backyard Composting Program (USA) findings from 1996. Metro Vancouver bases their per-composter diversion
on Seattle’s yard trimmings estimates, which is a significant underestimate.
Curbside Collection Implications
Seventy-nine percent of participating
households increased the amount of
material they composted and reduced the
amount of waste they put in the garbage.
Compared to the 2008 North Shore
average, participants decreased what they
placed at the curb by half a can of yard
trimmings and a full can of garbage each
week. All composting households on the
North Shore compost 8,398 to 10,514
tonnes that the municipalities never need
to handle or pay to tip each year; this is
equivalent to approximately 1,500 truck
trips and is almost the same quantity
(10,638 tonnes) as the current Yard
Trimmings collection service, which costs
$1,500,000 in fleet and salary-related
collection costs each year.
Diversion Rate Implications
The North Shore does not currently include backyard composting in its municipal diversion rates calculation of
59.5% (2010). When composting is factored in, the North Shore’s diversion rate is 67.2%: our single-family
diversion rate is higher than we’ve been reporting to municipal staff. Metro Vancouver (MV) uses the number of
bins distributed multiplied by 250 kg/bin to generate an estimate of organics generated and managed onsite
(4,052 tonnes). We find that the actual diversion due to composting households on the North Shore is 10,514
tonnes, 2.5 times greater than MV’s estimate; the regional residential sector diversion rate may be higher than
currently estimated.
Sophia (left) holds one week’s accumulation of
the family’s garbage while Melanie (middle) and
Ariadne (right) hold their household
compostables from the same week!
Backyard Composting Undervalued
Page v
Tipping Fees Avoided
Two-thirds of the total garbage and yard trimmings annual collection service costs are in the form of tipping fees.
At 2011 rates, each study household saves the municipality $35.44 in tipping fees each year. For the North Shore’s
population of composting households, this extrapolates to $874,227 each year in avoided tipping fee costs.
Tipping fee savings are cumulative so long as a composting household maintains its composting behaviour. Over
the last five years on the North Shore, we have invested approximately $16,100 in bin subsidies and backyard
composting has resulted in avoided tipping fees of
approximately $3,500,000.
Personalized Compost Coaching
With training, households compost almost 100 kg more each
year than unsupported households. Supported study
participants increased their diversion of low-quality
household papers from the garbage to the compost, kept
more leaves for onsite use, used alternative recycling depots for non-curbside collected materials and altered
buying habits to reduce waste at source. Compared to its low cost of delivery, personalized Compost Coaching
services provide immeasurable social and environmental value beyond the direct tipping fee savings and
decreased curbside collection requirements.
Selected Recommendations
Include backyard composting in the annual North Shore Single-Family diversion rate calculation, using a
per-household rate between 361 kg and 452 kg.
On an annual or bi-annual basis, collect statistically-significant data on the number of households
composting and usage of composting best practices.
Recognize annual costs avoided due to composting as a line item in budget summaries and planning
documents to municipal staff.
Increase support for onsite composting, the lowest-cost municipal waste diversion tool in the suite of
collection programs which has diversion and cost-saving results disproportionate to its minimal investment.
Allocate staff and resources to significantly increase the number of composting households, recognizing
that the scale of diversion through onsite composting is on par with curbside Yard Trimmings collection
and that the scale of incremental cost savings will be in the six figure range annually.
Introduce Compost Coaching or similar personalized training and troubleshooting service as a core
support component for all composter sales.
Completely integrate composter sale operations with community outreach functions.
We respectfully suggest that Metro Vancouver consider the following recommendations:
Request that municipalities submit number of households using compost bins derived from statistically
significant surveys, instead of using total number of bins distributed.
Capitalize on the advantage of scale to conduct more economical statistically-significant surveys
determining the number of households composting by municipality and for the overall Region.
Revise the 250 kg per bin factor upwards to between 361 kg and 452 kg per household.
We only made 2.5 kilograms of garbage in the
last 2 months and almost 50 kg of compost!
Melanie Solheim
Backyard Composting Undervalued
Page vi
Table of Contents
1. Introduction ................................................................................................................................... 1
A Need for Research and Testing ....................................................................................................................... 1
Objectives .......................................................................................................................................................... 2
2. Methods And Materials ................................................................................................................... 5
Volunteer Recruitment ....................................................................................................................................... 5
Set-Up and Training ........................................................................................................................................... 6
Study 1: Organic Waste Diversion ...................................................................................................................... 8
Study 2: Mega Composter .................................................................................................................................. 8
Study 3: Green Cone Food Waste Digester ......................................................................................................... 9
Volunteer Support.............................................................................................................................................. 9
Project Wrap-Up .............................................................................................................................................. 10
3. Data And Survey Results ................................................................................................................ 11
Composting Practices ...................................................................................................................................... 11
Study 1: Organic Waste Diversion .................................................................................................................... 15
Study 2: Mega Composter ................................................................................................................................ 18
Study 3: Green Cone Food Waste Digester ....................................................................................................... 21
Curbside Set Outs of Garbage and Yard Trimmings .......................................................................................... 29
Summary of Waste Diversion by Composting .................................................................................................. 30
4. Discussion And Research Implications ............................................................................................. 33
Other Onsite Organics Diversion Measurement Studies ................................................................................... 33
Curbside Collection Implications ....................................................................................................................... 37
Diversion Rate Implications .............................................................................................................................. 40
Tipping Fees Avoided ....................................................................................................................................... 43
Personalized Compost Coaching ...................................................................................................................... 46
Implications of Test Results for Garden Gourmet Alternatives.......................................................................... 47
5. Conclusions And Recommendations ............................................................................................... 49
Conclusions ...................................................................................................................................................... 49
Recommendations ........................................................................................................................................... 51
6. Acknowledgments ......................................................................................................................... 53
7. Works Cited .................................................................................................................................. 54
Backyard Composting Undervalued
Page vii
Table of Figures
Figure 2-1: Project timeline. ................................................................................................................................... 5
Figure 3-1: Volunteers’ confidence in their ability to compost/digest before and after the study........................... 12
Figure 3-2: Perceived change in quantity of organics diverted from curbside collection. ....................................... 14
Figure 3-3: Volunteers’ ratings of Compost Coaching sessions. ............................................................................. 14
Figure 3-4: Organics Diversion: household organic waste diverted per household by month. ............................... 16
Figure 3-5: Organics Diversion: yard trimmings diverted per household by month. ............................................... 17
Figure 3-6: Mega Composter: household organic waste diverted per household by month (n = 5). ....................... 19
Figure 3-7: Mega Composter: yard trimmings diverted per household by month (n = 5). ....................................... 20
Figure 3-8: Types of food waste diverted to the Green Cone. ............................................................................... 22
Figure 3-9: Location of Green Cones in sun or shade. ........................................................................................... 23
Figure 3-10: Number of households experiencing problems with the Green Cone ................................................ 23
Figure 3-11: Food scraps diverted to the Green Cone per household. .................................................................... 25
Figure 3-12: Food scraps being diverted to a supplemental backyard composter per household. .......................... 26
Figure 3-13: Total weight of food scraps diverted with the Green Cones and the composters. .............................. 27
Figure 3-14: Yard trimmings diverted by Green Cone households to a backyard composter (n = 5). ...................... 28
Figure 3-15: Amount volunteer households reduced their garbage over 2010. ...................................................... 29
Figure 3-16: Total household organic waste and yard trimmings actually diverted. .............................................. 30
Figure 4-1: Average annual diversion rates for household organic waste and yard trimmings. .............................. 36
List of Tables
Table 2-1: Number of Volunteer Households per Study. ......................................................................................... 6
Table 2-2: Definitions of the categories of organic waste used and the studies they apply to. ................................ 7
Table 2-3: Comparison of the Garden Gourmet and Mega Composters. ................................................................. 8
Table 3-1: Variety of indoor household materials composted, before and after study. .......................................... 12
Table 3-2: Variety of outdoor household materials composted before and after study. ........................................ 13
Table 3-3: Organics Diversion: household organic waste diverted per household by month. ................................. 16
Table 3-4: Organics Diversion: yard trimmings diverted per household by month. ................................................ 17
Table 3-5: Mega Composter: household organic waste diverted per household by month (n = 5). ......................... 20
Table 3-6: Mega Composter: yard trimmings diverted per household by month (n = 5). ....................................... 21
Table 3-7: Food scraps diverted to the Green Cone per household. ....................................................................... 25
Table 3-8: Food scraps being diverted to a supplemental backyard composter per household. ............................. 26
Table 3-9: Amount of food scraps diverted with the Green Cones and backyard composters. .............................. 27
Table 3-10: Yard trimmings diverted by Green Cone households to a backyard composter (n = 5). ....................... 28
Table 3-11: Average amount of garbage and yard trimmings placed at the curb. .................................................. 29
Table 3-12: Total household organic waste and yard trimmings actually diverted. ................................................ 31
Table 4-1: Percentage of households composting low-quality papers compared to 2008 baseline. ....................... 38
Table 4-2: Average amount of garbage and yard trimmings put out for collection in 2008 and 2010. ................... 38
Table 4-3: Measured and calibrated per household annual diversion rates due to backyard composting. ............. 39
Table 4-4: Extrapolated tonnages of waste diverted by SF households that municipalities never handle. ............. 39
Table 4-5: Differences between Metro Vancouver diversion rate factors compared to NSRP findings .................. 42
Table 4-6: Variations in North Shore diversion rate calculations (2010 and 2008 data). ........................................ 43
Table 4-7: Actual tipping fees avoided by the volunteer households in 2010. ........................................................ 44
Backyard Composting Undervalued
Page viii
Table 4-8: Average tipping fees that will be avoided in 2011 by households with compost training. ..................... 44
Table 4-9: Tipping fees avoided by North Shore municipalities due to onsite composting in 2011. ....................... 45
Backyard Composting Undervalued
L Page 1
1. Introduction
The North Shore Recycling Program (NSRP) is a tri-municipal agency of the City of North Vancouver, the District
of North Vancouver and the District of West Vancouver in British Columbia that administers the residential
curbside recycling program and recycling drop-off depot. Since its inception in 1990, the NSRP has also provided a
variety of community education programs that support residential waste reduction.
However, while recycling is important, it is only part of the waste reduction solution. There is much that can be
done to reduce the amount of garbage municipal residents generate and that municipal utilities collect. In
addition to considering the other three Rs: Reduce, Reuse, and Rethink, Backyard Composting has a large role to
play in partially diverting the heaviest and largest
component of the residential waste stream:
organics.
Backyard composting is the most effective and
environmentally-friendly way to manage the
organic “waste” a home produces, transforming
“trash” into “treasure” while keeping organic
material in the biological cycle. Metro Vancouver
(MV), the inter-municipal governing body of the
Greater Vancouver Regional District, estimates
that each compost bin distributed keeps 250
kilograms (kg) of organics off the curb per year,
resulting in free fertilizer for the garden and fewer
trucks on the road. But still, 37%1 of the garbage
sent for disposal from single-family homes could be
backyard-composted.
Following on from four years of research, surveys, pilot programs and evaluations focused on the topic of single-
family organic waste, the NSRP has come to believe that Metro Vancouver’s diversion rate attributed to
composters may be an underestimate and that North Shore residents may benefit from additional onsite compost
options for their households.
A Need for Research and Testing
Weigh Organics Composted per Household
Presently, the NSRP estimates the weight of organic waste composted by North Shore single-family (SF)
households (hh) using the following data:
61% of households use backyard composters.2
38,132 SF households on the North Shore.3
26.9 L/week average self-reported estimate of volume diverted by composting.4, 5
0.8 kg/L and 0.36 kg/L for food waste and 0.2 kg/L for yard waste density conversion factors.6, 7
Composting in Action!
Backyard Composting Undervalued
L Page 2
Based on these factors, we estimated that baseline North Shore households (with no composting support) are
keeping 415 kg/hh/year5 off the curb, resulting in 9,600 tonnes removed from curbside collection each year.
In a 2009 evaluation of a personalized Compost Coaching program8, we estimated (using the same methodology),
that households receiving training and support could keep 520 kg/hh/year off the curb.
With new household composting initiatives on our horizon, ranging from outreach techniques to curbside
collection systems, the NSRP required a more accurate measure of actual – and maximum possible – diversion
rates of household organics through backyard composting.
Test Alternatives to the Garden Gourmet
Of the many different types of composters available
on the market today, the NSRP chose to subsidize (by
$6.44) the “Garden Gourmet” composter (by Scepter,
right) for residents of the North Shore. In our 2008
Composter Follow-up Survey4, 5, 77% of the 950
respondents were satisfied or very satisfied with the
Garden Gourmet. However, 47% of respondents
indicated that the Garden Gourmet was not large
enough to handle the amount of organic waste they
wanted to compost, or had complaints about the top
lid or lower access hatch. Also, 16% of respondents
never aerate their compost, mainly due to time
constraints and perceived difficulty in doing so. Based
on these results, the NSRP decided to test and
evaluate alternatives for managing household organic
wastes (HOW) for North Shore households.
Objectives
Three separate studies were run concurrently to provide an accurate average annual per-household diversion rate
through backyard composting, and to evaluate alternatives for managing household organic waste at the source
(home):
1. Study 1: Organic Waste Diversion
2. Study 2: Suitability of the Mega Composter
3. Study 3: Suitability of the Green Cone Food Waste Digester
The volunteers who participated in this project were drawn from a pool of North Shore residents who were
already composting and who participated in the January 2008 Composter Follow-up Survey4. A number of tasks
were shared between the three studies for efficiency.
The NSRP subsidizes “Garden
Gourmet” composters like the ones
below to residents of the North
Shore.
Backyard Composting Undervalued
L Page 3
Study 1: Organic Waste Diversion
The primary objectives of the Organic Waste Diversion study were to:
refine the per-household annual estimates calculated from the January 2008 Composter Follow-up
Survey4, 5; and
more accurately estimate overall diversion rates through backyard composting on the North Shore.
The following were key tasks to meet these objectives:
For 11 months, volunteers weighed their household organic waste (food scraps, newspaper and low
quality papers such as paper towel and tissue, egg cartons and toilet paper rolls), and yard trimmings
being composted.
Extrapolation of the volunteers’ data to estimate the total weight of organic wastes composted on the
North Shore.
Study 2: Suitability of the Mega Composter
The main reason the Mega Composter (Mega) was
chosen for testing is because it is significantly larger than
the Garden Gourmet (see photo on the right). Also, it has
a large, spring-loaded lid that can be operated with one
hand and four lower access panels. In addition to
capacity, a number of other issues identified in the
January 2008 survey4 were also tested to determine if the
Mega Composter was a viable alternative to the Garden
Gourmet (GG).
The primary objectives of this study were to:
determine if the Mega is durable enough to
handle a large volume of material (kitchen
waste, low-quality household paper products,
and yard waste); and
assess ease of installation, operation and
resistance to pests.
The following were key tasks to meet these objectives:
For 11 months, volunteers weighed the amount of household organic waste and yard trimmings being
composted. This data was also analyzed for Study 1, Organic Waste Diversion.
Volunteers completed a post-study survey which included questions about installation, operation,
capacity and resistance to pests.
The Mega Composter (right) is more
than double the volume of the
Garden Gourmet (left). You can tell
the difference in size by the
Wingdigger™ aerating tool propped
in front of the composters.
Backyard Composting Undervalued
L Page 4
Study 3: Suitability of the Green Cone Food Waste Digester
The Green Cone (GC) is not a composter – it is a food
waste digester that can accept all types of food waste,
including those that are not recommended for
composting due to pest and bear concerns: meats,
dairy, bones and fats. The digestion process occurs
below ground, where microorganisms break down the
waste into nutrient rich water and carbon dioxide
leaving a small residue. Sunlight, rather than carbon-
rich materials, provides energy and the double walls of
the cone trap heat and permit air circulation to
encourage the growth of bacteria9.
Requiring good drainage and a year-round sunny
location, the GC is not an obvious choice for the North
Shore which is heavily treed and on low-permeability
glacial till (“hardpan”). But its potential for diverting
otherwise non-compostable food items without the
requirement of manual aeration or addition of high-
carbon “browns” was worth considering, since these are
significant barriers to successful onsite organic waste
diversion.
The primary objectives of this study were to:
determine if the GC is durable and large
enough to handle typical household food
waste volumes;
determine how effective the GC is for all types of food scraps;
assess ease of installation, operation and resistance to pests; and
determine if the GC is suitable for use on the North Shore as a viable alternative or companion to the
Garden Gourmet.
The following were key tasks to meet these objectives:
For 11 months, volunteers weighed the amount of household food scraps being digested and excess food
scraps and yard trimmings being composted.
Volunteers completed a post-study survey which included questions about installation, operation,
capacity and resistance to pests.
The Green Cone can take all types
of household food waste - meat,
dairy, bones and vegetables.
It cannot handle yard waste.
Backyard Composting Undervalued
L Page 5
2. Methods and Materials
Twenty-five households from the North Shore volunteered their time and were willing to weigh and track their
organic waste for an entire year. This project ran from October 2009 through to May 2011 and involved the
following stages:
Volunteer Recruitment (October –December 2009)
Set-up and Training (January – February 2010)
Data Recording (January – December 2010)
Volunteer Support (Throughout)
Project Wrap-up (January – February 2011)
Data Analysis and Reporting (February – May 2011)
The figure 2-1 shows the project timeline and key milestones.
October 2009 May 2011
Jan 10 Apr 10 Jul 10 Oct 10 Jan 11 Apr 11
30-Oct-09
Recruitment
Letter
MailedNov - Dec
Volunteer
Selection
Jan-10 - Dec-10
Data Recording
Jan - Feb
Set-up
and
Training
Jan - Feb
Wrap-up
Visits
31-Dec-10
Data
Recording
Ends
3-Feb-11
Wrap-up Party
Feb - May
Data Analysis
and Reporting
Figure 2-1: Project timeline.
Volunteer Recruitment
The volunteers who participated in this project were drawn from a pool of residents who were already
composting, not new to composting. Potential participants were contacted through a general letter mailed to a
list of 483 residents who had participated in the January 2008 Composter Follow-up Survey4 and had indicated an
interest in learning about pilot projects. The letter was mailed on October 30, 2009 and those interested were
requested to contact the NSRP directly (Appendix A). 104 households responded indicating interest in
participating. These households were then contacted by telephone and given a short interview to determine
suitability for the project and which study would be the best fit. Initially, twenty four households were selected to
participate with one more household joining the Green Cone study in June, 2010 (table 2-1). They represented a
wide variety of composter types and household sizes.
Backyard Composting Undervalued
L Page 6
Study Number of Volunteer
Households
Organic Waste Diversion 11
Mega Composter 5
Green Cone 9
Total 25 Table 2-1: Number of Volunteer Households per Study.
Set-up and Training
During January and early February, 2010, volunteer
households were required to undergo two separate
training sessions:
Project Start-up Training Session; and,
Compost Coaching
Households that received a Mega Composter or Green
Cone picked them up from the NSRP prior to their
training sessions and were required to transport and set
them up on their own. All households received organic
waste collection containers, scales and a data book with
instructions and data recording forms (Appendices B-D).
The container and scale(s) assigned were specific to the
study the household participated in.
Project Start-up Training Session
Individual project training sessions were held at
participants’ homes to get them up and running on the
project. Each household was required to complete a pre-
study survey (Appendix E) at the start of the project.
Topics of discussion at the session included:
types of acceptable organic wastes from yard
and household specific to the study (as outlined
in table 2-2);
how to weigh and record their compostables;
how low quality household paper waste was to
be collected and recorded with food waste; and
how to record the amount of garbage and yard
trimmings put at the curb each week.
Different organic materials were included in different
studies, depending on the diversion technique in use
Volunteers were provided with a
collection container, a scale and a
book with instructions and data
recording forms.
A separate container and scale were
provided for yard trimmings.
Backyard Composting Undervalued
L Page 7
and the participants’ willingness to weigh materials outside of their home (table 2-2). Data recording started upon
completion of the training session and continued to the end of the calendar year.
Materials included
Study 1:
Organic
Waste
Diversion
Study 2:
Mega
Composter
Study 3:
Green Cone
Food Scraps All food scraps, cooked or raw, including fruits,
vegetables, meats, fats, grains, dairy and bones No No Yes
Household
Organic
Waste
Selected food scraps (fruits, vegetables, coffee
grounds and tea, eggshells) and low-quality
household papers (shredded newspaper, paper
tissue and toweling, cardboard rolls, egg cartons
and other pressed-fibre containers)
Yes Yes No
Yard
Trimmings
Grass clippings, soft and woody plant prunings,
weeds, fallen leaves Yes Yes
Yes*
*In supplementary
compost bin only Table 2-2: Definitions of the categories of organic waste used and the studies they apply to.
Compost Coaching
In 2008, a NSRP Compost Training Pilot program evaluation8 indicated that participants would be most successful
and maximize their waste diversion if we provided personalized Compost Coaching. After the start-up training
session was complete, all participants received a
personalized at-home Compost Coaching session
based on the Composting in Bear Country
Guidelines10 jointly developed by the NSRP and
North Shore Black Bear Society. A NSRP staff
member with composting experience visited each
participating household. In the 45 minute session,
the following topics were covered (modified to
suit the needs of the household):
Basic biology and chemistry of
composting and how it works.
Best practices and rules of thumb for
successful composting.
Analysis and troubleshooting of existing
compost efforts.
Review of easily-sourced carbon-rich
materials to keep compost active.
Additional reduce, reuse and recycle
options to help curb waste generation.
A Green Cone study volunteer and NSRP
staff member discuss the best place to
locate the Green Cone
during a personalized at-home
Compost Coaching session.
Backyard Composting Undervalued
L Page 8
For those involved in the Mega Composter and Green Cone studies, emphasis was placed on determining
installation location if needed and best practices specific to the unit in question.
Study 1: Organic Waste Diversion
Eleven households participated in the Organic Waste Diversion study using their existing composting system.
They represented a wide variety of composter types and household sizes. All 11 volunteer households tracked
their household organic waste while three additionally tracked the amount of yard trimmings they composted
over the same time period.
Study 2: Mega Composter
Two of the issues with the Garden Gourmet was that some residents found it was not large enough to handle the
amount of organic waste they wanted to compost and that the lid was hard to manage with one hand3. The Mega
Composter was chosen to be tested as an alternative because it is significantly larger than the Garden Gourmet
(see table 2-3 for dimensions).
Garden Gourmet Mega Composter
Volume 11 cubic feet 23 cubic feet
Dimensions 2' W x 2' D x 3'3" H 2'10" W x 2'10" D x 3'6" H
Price $45.00 (subsidized) $70.00
Manufacturer Scepter Keter Group
Table 2-3: Comparison of the Garden Gourmet and Mega Composters.
Five households were selected to test out the Mega Composter. Preference went to those who:
had identified problems with the Garden Gourmet – particularly volume limitations; and
were willing to weigh and track their household organic waste and yard trimmings.
Mega Composters and a Wingdigger™ aerating tool were provided to these participants free of charge.
Backyard Composting Undervalued
L Page 9
Study 3: Green Cone Food Waste Digester
Unlike a composter, the Green Cone is a food waste
digester that can take all types of food waste - meat,
dairy, bones and vegetables but it cannot handle yard
waste or high-carbon materials.
Eight Green Cones were available for testing either as a
stand-alone waste diversion option or in tandem with an
existing composter. Each household was provided with a
Green Cone, a 4L kitchen “caddy”, bacterial accelerator
powder and a powder shaker. Preference went to
households that were:
willing to try out all types of food waste - meat,
dairy, bones and vegetables;
willing to put in the required effort to dig a hole
90 cm wide x 70 cm deep for installation;
not larger than an average family of four or five;
met the minimum sunlight and drainage
requirements recommended by the
manufacturer; and
willing to weigh/track their compostable
materials throughout an entire year.
Three households also weighed and tracked their yard
trimmings composted in a conventional composter.
Volunteer Support
Guidance and support were available to the volunteers
throughout the duration of the study from the project
team at the North Shore Recycling Program. Site visits
were conducted in late spring to check in and ensure data
recording was being done correctly and to troubleshoot
any problems they may have had with their composter or
Green Cone. Monthly newsletters containing information
on the project status and upcoming events were sent out,
an online private social network was established to share
stories and photos and periodic telephone calls were
conducted to keep in touch.
The Green Cone (below right)
measures <70 cm in height above
ground, 59 cm in diameter at the
base, narrowing to 28 cm at the
top. The Garden Gourmet (left)
measures 99 cm in height.
Significant effort is required to dig
the hole for the Green Cone.
Backyard Composting Undervalued
L Page 10
Three volunteer appreciation and learning events were
held throughout the duration of the project:
Jenny Rustemeyer and Grant Baldwin presented a
humorous and inspiring 20 minute summary of
their Clean Bin Project11 at the Lynn Canyon
Ecology Center (May 2010).
Fraser Richmond Soil & Fibre Ltd. provided a tour
of their industrial composting facility that handles
all yard trimmings waste collected on the North
Shore (June 2010).
The Cascadia Society, one of the Green Cone
households, hosted an end-of-summer garden
party lunch and tour of their intensive backyard
composting systems (September 2010).
Project Wrap-up
In January 2011, individual visits to volunteers’ homes were
conducted to wrap up their role in the project and
included:
completion of a post-study survey (Appendix F);
collection of data books and scales; and
presentation of a gift of appreciation.
The post-study surveys collected information about the
volunteers’ garbage and composting practices,
demographic information, the installation and use of the
Green Cone or Mega Composter for Studies 2 & 3 and any
particular problems that were encountered. The data was
reviewed and compiled in a database for further analysis.
The completion of the project was celebrated with an all-
ages wrap-up party in February 2011 attended by 47
members of the volunteer households.
Jenny and Grant talking garbage
(or lack thereof).
The volunteers in front of
a finished compost pile at
Fraser Richmond Soil & Fibre.
Cascadia Society Garden Tour.
Backyard Composting Undervalued
L Page 11
3. Data and Survey Results
When the project was proposed, it was hoped that compost data would be obtained for the entire year from
January through December 2010. Due to a number of reasons, such as frozen ground preventing Green Cone
installation, most volunteers didn’t get up and running until February 2010. Only data recorded for full months
was used in the analyses.
Some of the results discussed below include data from all of the
studies and some are study-specific:
Composting Practices (includes data from all studies)
Study 1: Organic Waste Diversion
Study 2: Mega Composter
Study 3: Green Cone Food Waste Digester
Curbside Set Outs of Garbage and Yard Trimmings
(includes data from all studies)
Summary of Waste Diversion by Composting (includes data from studies 1 & 2)
Different organic materials were included in different studies, depending on the diversion technique in use and
the participants’ willingness to weigh materials outside of their home (table 2-2).
Composting Practices
To ensure all volunteer households were using best composting practices, all participants were required to have a
personalized at-home Compost Coaching session subsequent to the start-up training sessions. During the start-up
training, volunteers were required to complete a pre-study survey that had specific questions designed to
evaluate the following composting practices when compared with the post study-surveys:
Confidence level in composting ability
Materials composted
Perceived change in volumes composted
Confidence Level in Composting Ability
One of the questions asked on both pre- and post-study surveys (Appendices E and F) was:
“How confident or comfortable are you in your ability to compost or digest your kitchen scraps and
yard trimming successfully?” on a scale of 1 to 7 with 7 being “Very confident”.
In the pre-study survey, 17 of the 25 volunteers indicated they were very confident (7) in their composting abilities
(figure 3-1). Of the eight that initially rated themselves a 5 or 6, five indicated their confidence level improved
while three indicated no change. The average confidence rating, both before and after the study, was 6.5.
The 25 volunteer households
diverted a grand total of
7280 kg of organic waste from
curbside collection.
Backyard Composting Undervalued
L Page 12
Figure 3-1: Volunteers’ confidence in their ability to compost/digest before and after the study.
Materials Composted
To assess any changes in the variety of household organic waste and yard trimmings materials composted,
volunteers from Studies 1 and 2 were asked the following questions in the pre- and post-study surveys and asked
to check composted items from a list:
1. “Which of these items from inside your home or kitchen do you put in your compost?”
2. “Which of these yard and garden items do you put in your compost bin? “
Before Compost Coaching and this study, the only categories of organic materials composted by more than half
the volunteers were “fruits and vegetables” and “paper towels, tissue, paper napkins” (table 3-1). The percentage
of volunteer households composting increased for all categories of organic materials. More than half of all study
participants are now composting in all seven categories except “household cleanings” (floor sweepings and/or lint)
and “dairy, meat, grains, fats”. Surprisingly, in this latter category of food items that are considered less than
desirable for composting in bear country, there was a noticeable jump in the percentage of households that were
comfortable and confident enough to compost these significant items from their organic waste stream.
(n = 16) Pre-Study Post-Study
Fruits and vegetables 100% 100%
Dairy, meat, grains, fats 13% 38%
Egg shells, coffee grounds, tea bags 25% 94%
Household cleanings (floor sweepings, lint) 19% 31%
Paper towels, tissue, paper napkins 56% 75%
Paper bags, paper towel or toilet paper roll cores 44% 50%
Newspaper 44% 63%
Table 3-1: Variety of indoor household materials composted, before and after study.
17
4
4
Confidence in Composting Ability Before Study
7
6
<=514
10
1
Confidence in Composting Ability After Study
7
6
<=5
Backyard Composting Undervalued
L Page 13
The categories of outdoor materials composted both before and after the study are virtually the same (table 3-2).
Post-study survey comments and interviews indicated that even though the number of households composting
leaves stayed almost the same, most households increased the quantity of leaves composted.
(n = 25) Pre-Study Post-Study
Grass/lawn clippings 60% 56%
Fallen leaves 92% 96%
Soft plant prunings 88% 84%
Woody plant prunings 32% 40%
Table 3-2: Variety of outdoor household materials composted before and after study.
Perceived Change in Volumes Composted
Volunteers from Studies 1 and 2 were asked to indicate their perception of any changes in the quantities of
organic materials that their household composts since the Compost Coaching session:
Please select the statement that BEST describes the volumes of organic material you divert from
curbside collection. "Since the Compost Coaching session, the quantity of organic materials that we
compost or mulch in our yard has...
remained the same."
increased."
decreased."
"We do not compost any organic materials in our yard; it is all placed at the curb for collection"
Over three-quarters of all study participants reported that they increased the quantity of organics they divert
from curbside collection since the start of the study and the Compost Coaching sessions (figure 3-2).
“Our composting practices have changed dramatically. We now understand the mix of green and brown waste. With the addition of leaves,
we have the best compost we’ve ever had in the past five years. I am so excited to be rid of the sludgy, stinky mess we usually have.”
Jennifer Read
Backyard Composting Undervalued
L Page 14
Figure 3-2: Perceived change in quantity of organics diverted from curbside collection.
Compost Coaching
In the post-study survey, all volunteers were asked:
“On a scale of 1 to 7, how useful did you find the Compost Coaching Session at the beginning of the
study (1 = “Not at all”, 7 = “Very”), and would you recommend a session to others?”
68% rated the Compost Coaching session as “Very useful” (figure 3-3). Those who rated the Compost Coaching
session a 4 or 5 did so because they were already very knowledgeable about composting and much of the
information presented was familiar. While these volunteers may not have found the session as “useful” as others
did, 100% of participants recommended Compost Coaching sessions for North Shore residents, particularly those
new to composting.
Figure 3-3: Volunteers’ ratings of Compost Coaching sessions.
79%
21%
0%0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
Increased Remained the same Decreased
Perc
en
tag
eQuantity of Organic Materials Diverted from
Curbside Collection has...
17
4
22
Value of Compost Coaching Session
7
6
5
<=425
Recommend Compost Coaching?
Yes
No
Backyard Composting Undervalued
L Page 15
Study 1: Organic Waste Diversion
Eleven households participated in the Organic Waste Diversion
study weighing their compostables and using their existing
composting systems. Nine of the eleven households had at
least one Garden Gourmet on site. Five of the households were
using a different type of composter. The others systems in use
included:
NatureMill Electric Composter;
Earth Machine;
Homemade wooden “compost corral”; and
Plastic construction fencing (below)
Waste Diversion
The amount of organic waste diverted per household is broken down into the following two categories:
Household organic waste, and
Yard trimmings
The 11 Study 1 households diverted 3082 kg of organic waste from curbside collection between Feb and Dec 2010:
Household: 1641 kg
Yard Trimmings: 1441 kg
One family uses simple orange plastic construction fencing to define their compost
heaps. It works for them because “air can get at the composting material, it is easy aerate
the compost with a pitchfork, and when it’s ready to harvest, the orange fence is removed
altogether to shovel away.” Bears and other potential pests have not been attracted to their
well-maintained composting operations.
Backyard Composting Undervalued
L Page 16
Household Organic Waste
The average and range of household organic waste in kilograms (kg) diverted per household between the months
of February and December 2010 is shown in figure 3.4. Table 3-3 lists the corresponding average amounts per
household and total amounts of household organic waste diverted per month.
Figure 3-4: Organics Diversion: household organic waste diverted per household by month.
Eleven households participated in the study however the number of complete data sets per month varied due to
factors such as extended vacations. The number of households used to calculate the monthly averages and total
numbers are listed in the final row of the table. The total amount of household organic waste diverted from
curbside collection by Study 1 households was 1641 kg.
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 134.3 142.7 122.5 127.5 160.9 172.1 218.0 133.6 114.4 191.8 133.9
Average (kg)/
household 13.4 14.3 12.3 12.8 14.6 15.6 19.8 13.4 12.7 21.3 13.4
Number of
Households 10 10 10 10 11 11 11 10 9 9 10
Table 3-3: Organics Diversion: household organic waste diverted per household by month.
0
10
20
30
40
50
60
Feb Mar AprMay Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Average Weight (kg) of Household Organic Waste Diverted per Volunteer Household
Average
Minimum
Maximum
Backyard Composting Undervalued
L Page 17
Yard Trimmings
Six of the eleven households weighed and recorded the amount of yard trimmings they diverted for the year.
Figure 3-5 shows the average and range of weights of yard trimmings in kilograms (kg) diverted per household
between the months of February and December, 2010. Table 3-4 lists the corresponding average per household
and total amounts of yard trimmings diverted per month.
Figure 3-5: Organics Diversion: yard trimmings diverted per household by month.
The number of households composting
yard trimmings in a given month
ranged from 2 to 6 due to the fact some
garden sporadically (table 3-4). The
total amount of yard trimmings
diverted from curbside collection by
Study 1 participants was 1441 kg.
Combining the household organic
waste total with the yard trimmings total gives a grand total of 3082 kg of organic waste diverted from curbside
collection by the volunteer households in Study 1.
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted (kg) 63.0 237.6 232.5 112.9 169.2 90.5 148.6 105.1 141.9 70.5 69.0
Average (kg)/
household 31.5 59.4 116.3 28.2 28.2 22.6 29.7 26.3 47.3 35.3 13.8
Number of
Households 2 4 2 4 6 4 5 4 3 2 5
Table 3-4: Organics Diversion: yard trimmings diverted per household by month.
0
50
100
150
200
250
Feb Mar AprMay Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Average Weight (kg) of Yard Trimmings Diverted per Volunteer Household
Average
Minimum
Maximum
I've been adding more carbon in the form of leaves and more dedicated layering. I also add more paper products such as napkins
and paper towels.
Peter Chappell
Backyard Composting Undervalued
L Page 18
Study 2: Mega Composter
All five households testing the Mega Composter (Mega) participated to the end of 2010. They all plan to continue
composting but only three will continue using the Mega. One composter was “completely trashed” at the end of
the project and thrown out. The other was infested by rats and falling apart; it will be used for leaf storage in the
future once the compost is harvested. Household size
ranged from two adults to a family of five with three kids.
Survey Responses
Volunteers were asked to evaluate the Mega Composter’s
capacity, durability, resistance to pests and ease of
installation and operation on the post-study survey
(Appendix F):
Ease of Installation: Rated an average 6 out of 7,
where 1 was “Not and all” and 7 was “Very”. It was
easy to transport, the instructions were clear and it
took between 15 and 60 minutes to set up.
Lid operation: 4 of 5 volunteers found the lid was
easy to operate (the 5th broke).
Lower doors: 4 of 5 volunteers had problems with
the doors at the bottom of the composter “bowing
out”, “popping off” and/or breaking. They used a
variety of methods to stop this from happening.
Capacity: 4 of 5 found the capacity sufficient for
the amount of material they wanted to compost.
Construction: All five found the plastic thin, weak
and flimsy and less durable than the Garden
Gourmet.
Performance: Two volunteers said the Mega
performed better than expected compared to the
Garden Gourmet, 1 the same as and 2 worse than
expected.
Aerating: One volunteer reported difficulty
aerating due to the size of the Mega when the
volume of material inside approached capacity.
Pests: 3 of 5 had a major problem with pests, 1 a minor
problem and 1 no problem. In addition to regular
aeration and addition of carbon-rich material, a variety
of methods were used to deter pests such as providing
barriers to prevent the doors from being opened by
crafty raccoons (see bottom photo in sidebar), plugging
holes to prevent access and using rat traps.
Four out of five households had
problems with the lower doors
of the Mega Composter
“bowing out” (below), popping
off or breaking.
They used a variety of methods
to prevent this from happening
and to deter pests from popping
off the doors or gaining access.
Backyard Composting Undervalued
L Page 19
Recommend: 3 of 5 would recommend the Mega Composter to other North Shore residents.
Continued use: 3 of 5 are continuing to use the Mega as a composter however 1 will cease using it when
they’ve built a composter made of wood and mesh. Another who had major rat issues will use it only for
leaf storage once the existing compost is harvested.
Waste Diversion
In order to test the capacity of the Mega Composter, all five households weighed and recorded their household
organic waste and yard trimmings.
Household Organic Waste
Figure 3-6 shows the average and range of weights of
household organic waste in kilograms (kg) diverted per
household between the months of February and December,
2010. During that time, the average amount of household
organic waste being diverted to the Mega Composter per
household was 21 kg per month, with a low point in August and
the peak in November due to Hallowe’en pumpkins. Table 3-5
lists the corresponding average per household and total
amounts of household organic waste diverted per month.
Figure 3-6: Mega Composter: household organic waste diverted per household by month (n = 5).
0
10
20
30
40
50
60
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Mega Composter: Average Weight (kg) of Household Organic Waste Diverted per Household
Average
Min
Max
The 5 Mega Composter households diverted 1805 kg of organic waste from curbside collection between Feb and Dec 2010:
Household: 1156 kg
Yard Trimmings: 649 kg
Backyard Composting Undervalued
L Page 20
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 98.6 101.5 98.9 109.6 107.6 102.7 78.3 99.8 107.2 144.4 107.4
Average (kg)/
household 19.7 20.3 19.8 21.9 21.5 20.5 15.7 20.0 21.4 28.9 21.5
Table 3-5: Mega Composter: household organic waste diverted per household by month (n = 5).
The total amount of household organic waste diverted from curbside collection by the Mega Composter
households between February and December was 1156 kg.
Yard Trimmings
The average and range of weights of yard trimmings in kilograms (kg) diverted per household between the
months of February and December, 2010 is shown in figure 3-7. Table 3-6 lists the average per household and total
amounts of waste diverted per month.
Figure 3-7: Mega Composter: yard trimmings diverted per household by month (n = 5).
0
50
100
150
200
250
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Mega Composter: Average Weight (kg) of Yard Trimmings Diverted per Household
Average
Min
Max
Backyard Composting Undervalued
L Page 21
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 24.8 38.1 33.8 74.8 83.4 98.2 58.0 76.7 87.8 71.0 2.4
Average (kg)/
household 6.2 9.5 8.5 18.7 16.7 19.6 14.5 25.6 29.3 17.8 2.4
Number of
Households 4 4 4 4 5 5 4 3 3 4 1
Table 3-6: Mega Composter: yard trimmings diverted per household by month (n = 5).
The number of households composting yard trimmings in a given month ranged from 1 to 5 due to the fact some
volunteers garden sporadically (table 3-6). The total amount of yard trimmings diverted was 649 kg. Combining
the household organic waste total with the yard trimmings total gives a grand total of 1805 kg of organic waste
diverted from curbside collection by the volunteer households in Study 2.
Study 3: Green Cone Food Waste Digester
Of the eight volunteer households involved in this study, one returned their Green Cone after two months due to
pest issues. Raccoons were attracted to the Green Cone and dug deep all around it destroying the resident’s
perennial garden. The Green Cone and materials were returned and given to another household for testing,
bringing the total to nine households participating in the study. All other participants used their Green Cones until
the end of the study period except when limited by capacity (see below).
Survey Responses
Volunteers were asked to evaluate the Green Cone’s ease of installation and operation, effectiveness at digesting
food scraps, capacity, durability and resistance to pests on the post-study survey (Appendix F).
Installation and Operation
Ease of installation was rated an average of 5.6 out of 7, (1 = “Not at all” and 7 = “Very”), with participants’
responses spanning the entire range. It was easy to transport, the instructions were clear to most volunteers and it
took between one-half hour to two days (due to first moving a shrub) to set up but averaged around 3-4 hours.
Digging the hole for installation proved to be quite a challenge in some locations and was the most time-
consuming task.
The Green Cone lid was easy to operate. There were a few issues with the small size of the hole for adding food
scraps resulting in food pouring down the outside. This was due in part to the bar across the top of the Cone if it
wasn’t removed during installation, as recommended.
Backyard Composting Undervalued
L Page 22
Food Scrap Digestion
Prior to using the Green Cone, all of our participants composted their raw fruit and vegetable scraps but disposed
of their other household food waste in the garbage. Figure 3-8 shows the types of materials that were diverted to
the Green Cones during the study.
Figure 3-8: Types of food waste diverted to the Green Cone.
Capacity
According to the installation manual9, the maximum amount of food scraps recommended for addition to the
Green Cone is one full ‘caddy’ (4 L) every one to two days during summer and one full ‘caddy’ every two to three
days during winter.
During the colder months, the Green Cone digestion process did not adequately handle the amount of food waste
generated by the participating households. Some volunteers had to reduce the amount of food waste diverted to
the Cone, and either used their existing composters for the excess or threw the food scraps in the garbage:
One household found the capacity adequate with only one person living in the home.
Two households overloaded the Green Cones and undigested food was up to half the height of the cone
above ground.
The remaining five households who participated to the end of 2010 found the Green Cone wasn’t able to
digest the amount of material they composted. All five were able to use their composters to handle the
excess food scraps.
As mentioned previously, the digestion process occurs below-ground; sunlight provides energy and the double
walls of the cone trap heat and circulate the air to encourage the growth of bacteria. The volunteers were asked
how much sun their Green Cone location received during the summer and winter, when the digestion processes
slow down (figure 3-9). For the Green Cone to function at maximum efficiency, the more sun, the better.
0
2
4
6
8
10
Meat and bones
Bread and grains
Cooked fruit and veg
Raw fruit and veg
Dairy Egg shells, coffee
grounds
Household cleanings
Animal excrement
Nu
mb
er
of H
ou
se
ho
lds (
n=
9)
Types of Household Organic Waste Diverted
Backyard Composting Undervalued
L Page 23
Figure 3-9: Location of Green Cones in sun or shade.
Full winter sunlight is in short supply on the North Shore in the winter months, except in some neighbourhoods
that have had most of the tall trees removed.
Issues:
All households experienced problems with the Green Cone, and most households had more than one. The five
most frequently occurring problems are shown in the figure 3-10. The biggest problem was due to wildlife digging
around the Green Cone; eight out of nine households had this occur and had to do post-installation reinforcement
of the area around their Green Cone to deter the critters. One animal that wasn’t a problem, however, was the
black bear. One volunteer saw a bear wander by their Green Cone and ignore it; no other volunteers reported bear
sightings or issues. Also absent as a problem was odour.
Figure 3-10: Number of households experiencing problems with the Green Cone
0
1
2
3
4
5
6
7
Summer Full Sun
Summer Partial Sun
Summer Mostly Shade
Winter Full Sun
Winter Partial Sun
Winter Mostly Shade
Num
ber
of
Hou
seh
old
s (
n=
9)
Amount of Sunlight Available in Summer and Winter
0
1
2
3
4
5
6
7
8
9
Wildlife Excavation
Slow Degradation
Flies Maggots Smell Bears
Num
ber
of H
ousehold
s (
n=
9)
Number of Households Experiencing Problems with...
Backyard Composting Undervalued
L Page 24
One household had so many maggots (fly larvae) inside the
Green Cone and on the lid in the summer that they spilled
over when the lid was open and the plastic of the cone on the
inside was obscured. Only one household had an animal (in
this case a rat) penetrate the plastic underground basket.
This Green Cone was uninstalled to deal with rat problem but
has been reinstalled and reinforced with metal hardware
cloth around the buried plastic basket to preclude gnawing
rodents.
Recommend?
Four households indicated the Green Cone performed better
than expected, three as expected and two worse than
expected. Despite this and the pest problems, all nine
volunteers would recommend the Green Cone to other
North Shore residents. Eight households are continuing to
use the Green Cone and one will not continue as the site on
their property proved inadequate.
Waste Diversion
The Green Cone was not able to handle the total amount of
household organic waste that the volunteer households
produced over the duration of the study with the exception of
one household. Not enough sunlight during the winter months
and adding too much household organic waste likely
contributed to the slow digestion issues for most of the
volunteers. Five of the households used a combination of their
Backyard Composter and the Green Cone. The amount of
organic waste diverted per household is broken down into the
following categories:
The 8 Green Cone households diverted 2059 kg of organic waste from curbside collection between Feb and Dec 2010:
Green Cone: 1087 kg
Composter: 387 kg
Yard Trimmings: 585 kg
One example of post-installation
reinforcement by a volunteer who
used beach rocks to deter digging
around their Green Cone by the
local skunk.
The Green Cone did not work for my garden yet I was extremely impressed with how well it worked. If I had not had the raccoon problem, I would have continued with this
program.
Randi Sinclair
Backyard Composting Undervalued
L Page 25
Household food scraps only (no paper products):
o Green Cone
o Supplemental composter, and
o Combined totals for Green Cone and supplemental Composter
Yard trimmings
Household Food Scraps: Green Cone
Figure 3-11 shows the average weight and the range of household food scraps (kg) diverted to the Green Cone per
household between the months of February – December, 2010. Table 3-7 lists the average per household and total
amounts of food scraps diverted per month.
Figure 3-11: Food scraps diverted to the Green Cone per household.
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 81.1 122.3 104.4 104.6 72.1 100.7 107.4 100.9 112.9 100.5 80.6
Average (kg)/
household 10.1 15.3 14.9 14.9 10.3 12.6 13.4 12.6 14.1 12.6 11.5
Number of
Households 8 8 7 7 7 8 8 8 8 8 7
Table 3-7: Food scraps diverted to the Green Cone per household.
0
10
20
30
40
50
60
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Weig
ht
(kg
)
Average Weight (kg) of Food Scraps Diverted per Household in Green Cone Only
Average
Minimum
Maximum
Backyard Composting Undervalued
L Page 26
Household Food Scraps: Composter – When Used as an Overflow for a Green Cone
Figure 3-12 shows the average weight and the range of food scraps (kg) diverted to a backyard composter to
handle the overflow from the Green Cone. Table 3-8 lists the corresponding average per household and total
amounts of food scraps diverted per month.
Figure 3-12: Food scraps being diverted to a supplemental backyard composter per household.
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 13.8 20.8 17.0 28.1 35.1 43.0 32.4 44.5 43.3 54.3 55.0
Average (kg)/
household 6.9 6.9 5.7 7.0 7.0 8.6 6.5 8.9 8.7 13.6 11.0
Number of
Households 2 3 3 4 5 5 5 5 5 4 5
Table 3-8: Food scraps being diverted to a supplemental backyard composter per household.
0
10
20
30
40
50
60
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Average Weight (kg) of Food Scraps Diverted per Household by Composter when a Green Cone is also in
use.
Average
Minimum
Maximum
Backyard Composting Undervalued
L Page 27
Household Food Scraps: Green Cone and Composter Combined
The total amount of food scraps diverted each month by the Green Cone and the five supplementary backyard
composters used for the excess is shown in figure 3-13 and listed in table 3-9.
Figure 3-13: Total weight of food scraps diverted with the Green Cones and the composters.
One of the Green Cones was not in use during the months of April through June while a new volunteer household
was recruited to replace the one that had to withdraw from the study.
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Green Cone 81.1 122.3 104.4 104.6 72.1 100.7 107.4 100.9 112.9 100.5 80.6
Composter 13.8 20.8 17.0 28.1 35.1 43.0 32.4 44.5 43.3 54.3 55.0
Total 94.9 143.1 121.5 132.7 107.1 143.7 139.9 145.4 156.1 154.8 135.6
Number of
Households 8 8 7 7 7 8 8 8 8 8 7
Table 3-9: Amount of food scraps diverted with the Green Cones and backyard composters.
The amount of food scraps diverted from curbside collection by the “Green Cone” volunteer households in Study 3
was 1087 kg to the Green Cone and 387 kg to a supplemental composter for a grand total of 1474 kg combined.
0
20
40
60
80
100
120
140
160
180
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
We
igh
t (k
g)
Total Weight (kg) of Food ScrapsDiverted per Household
Composter
Green Cone
99% of the food scraps from our kitchen go into the Green Cone digester
or our Garden Gourmet compost bin.
Karen Todd
Backyard Composting Undervalued
L Page 28
Yard Trimmings: Composter Only
Five of the Green Cone households weighed and recorded their yard trimmings regularly throughout the year.
Figure 3-14 shows the average weight and the range of yard trimmings in kilograms (kg) diverted per household
between the months of February and December, 2010. Table 3-10 lists the average per household, total amounts
of waste diverted per month and the number of Green Cone households that composted and recorded yard
trimmings weights that month.
Figure 3-14: Yard trimmings diverted by Green Cone households to a backyard composter (n = 5).
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total diverted
(kg) 10.0 11.0 24.1 263.0 104.4 28.9 44.8 24.1 36.5 31.0 7.7
Average (kg)/
household 5.0 5.5 24.1 65.8 26.1 9.6 14.9 8.0 12.2 31.0 3.9
Number of
Households 2 2 1 4 4 3 3 3 3 1 2
Table 3-10: Yard trimmings diverted by Green Cone households to a backyard composter (n = 5).
The number of Green Cone households that composted yard trimmings in a given month ranged from one to four
(table 3-10). The total amount of yard trimmings diverted by Study 3 participants was 585 kg.
0
50
100
150
200
250
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Weig
ht
(kg
)
Average Weight (kg) of Yard Trimmings Diverted per Household by Composting
Average
Minimum
Maximum
Backyard Composting Undervalued
L Page 29
Curbside Set Outs of Garbage and Yard Trimmings
All households were asked to record the amount of garbage and yard trimmings put at the curb each week,
estimated in ¼ can increments. The average amount
per household is shown in Table 3-11.
Average
Amount per
Week
Range
Garbage
(77 L Can) 0.77 0.0 – 4.0
Yard Trimmings
(Bags or Cans) 1.18 0.15 – 18.50
Table 3-11: Average amount of garbage and yard trimmings placed at the curb.
One-third of the volunteer households put out less than ½
a can of garbage each week on average while two-thirds
put out less than 1 can of garbage per week. Only one
third of the households put out more than 1 can per week.
At the end of the project on the post-study survey, all
households were asked:
Over the study did you notice a reduction in the volume of waste you put into your garbage bin?
Figure 3-15 shows the percentage of households that did or did not reduce their garbage over the course of the study.
Figure 3-15: Amount volunteer households reduced their garbage over 2010.
50%
29%
21%
0%
10%
20%
30%
40%
50%
60%
Yes, significantly
Yes, a small amount
No
Perc
en
tag
e
Reduction in the Amount of Waste Put in Garbage Can
“We’ve always been environmentally
aware and have tried hard to cut down
on our waste. Seeing Jen and Grant’s
presentation on their Clean Bin Project
really was a catalyst for our family of 6
– to push us to take it to the next level:
recycling beyond the blue box at
community depots; only buying
products with no or recyclable
packaging; and maximizing our
composting. Composting was the
critical step to get us almost to zero
waste. If we install a Green Cone for our
meats and bones, there will be not
much left but fruit stickers!”
Jennifer Read
Backyard Composting Undervalued
L Page 30
Seventy-nine percent of households indicated that they had reduced the amount of waste they put in the garbage
by the end of the project, with two-thirds of households reducing their curbside garbage set-outs to less than one
can per week. Although we did not specifically ask on our post-study surveys, 20% of households mentioned that
they’ve been able to slash their garbage volumes dramatically. This was done by altering their purchasing habits
over the course of the study to reduce waste even more than simply by maximizing their composting diversion.
Summary of Waste Diversion by Composting
Data from all three studies were used to generate an average organics diversion rate per household. The data
from Studies 1: Organic Diversion and 2: Mega Composter was combined to show the total amount of household
organic waste diverted by composting between February and December 2010. Data from sixteen volunteer
households was used (figure 3-16 and table 3-12). As described previously, only some participating households
weighed the amount of yard trimmings they put in their composters. The data from ten households from all three
studies were used in the diversion calculations:
Organic Diversion: three households
Mega Composter: four households
Green Cone: three households
Figure 3-16: Total household organic waste and yard trimmings actually diverted.
0
100
200
300
400
500
600
700
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Weig
ht
(kg)
Total Weight of Organic Waste Diverted per Month
Yard Trimmings (n = 10)
Household (n = 16)
Backyard Composting Undervalued
L Page 31
Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Totals
Household
(n = 16) 222.4 244.2 221.4 237.1 268.5 274.8 296.3 233.4 221.6 336.2 241.3 2797.3
Yard
Trimmings
(n = 10)
87.3 258.6 286.2 406.2 275.3 200.2 228.7 204.4 266.2 172.5 65.5 2451.0
Total 309.7 502.8 507.7 643.3 543.7 475.0 525.0 437.8 487.8 508.7 306.8 5248.3
Table 3-12: Total household organic waste and yard trimmings actually diverted.
Average Household Organic Waste Diversion
To estimate the average annual amount of household
organic waste diverted by backyard composting, the data
collected over the 11 months was extrapolated to 12
months resulting in a diversion rate of 206 kg/hh/year.
Average Yard Trimmings Diversion
Although we began our study with the highest hopes for
simple, clean data, the interpretation of yard trimmings
data proved to be challenging for several reasons:
the per-month data is highly variable between households;
the per-month data is highly variable over the course of the year; and
the regularity of data entries varies widely from household to household.
We should have expected high variability: there are so many variations in yard size (garden lots vs. patio gardens);
gardening techniques (grasscycling, mulching); and styles (major spring or fall clean-ups vs. regular, smaller-scale
gardening work). The quantity of material actually composted in a bin (compared to being used directly elsewhere
in the yard) is highly dependent on individual households’ gardening practices.
The criteria used to screen data for this important final summary was that a household had to have recorded
regular yard trimming data entries for at least seven of the eleven study months. This allowed us to be confident
that all yard trimmings were weighed as they were amassed.
The average amount of Yard Trimmings diverted by backyard composting is 246 kg/hh/year, assuming no yard
trimmings composted in the month of January.
If all households’ data were summarized, including those with less consistent data entries, the average total of
yard trimmings decreases to 167 kg/hh/year.
The average annual diversion rates, based on 11 months of actual measurements are:
HOW: 206 kg/hh/yr
Yard Trimmings: 246 kg/hh/yr
Combined: 452 kg/hh/yr
Backyard Composting Undervalued
L Page 32
Combined Average Organic Waste Diversion
The average annual diversion rates for household organic waste plus yard trimmings, based on the backyard
composting data measured for eleven months in this study, totals 452 kg/hh/year.
I really believe that we owe you and your team working on the NSRP
Compost Research Project a huge debt of gratitude.
You've given us the opportunity to do something so worthwhile not just
for our immediate community but beyond it and as far as the positive
results of our study can spread.
I wouldn't presume to speak for anyone other than my partner Nancy
and me, but opportunities like the one we have been lucky enough to be
part of over the last year, dealing with reduction and diversion of
organic waste, are few and far apart.
Your pilot project regarding waste management and composting has
been genuinely instructive, supportive, and above all has given us the
feeling that we are accomplishing something of real value because of
the literally tangible nature of our results.
Thank you.
Peter Chappell
Backyard Composting Undervalued
L Page 33
4. Discussion and Research Implications
The results of our data measurements and pre- and post-study surveys suggest some important avenues to
explore, ranging from our local North Shore to the broader region. In this section, we will compare our results and
describe possible consequences of our findings on the following solid waste themes:
Other onsite organics diversion measurement studies
Curbside collection implications
Diversion rate implications
Tipping fees avoided
Personalized compost coaching
Test results for Garden Gourmet alternatives
Other Onsite Organics Diversion Measurement Studies
Although we are not aware of any backyard organics diversion study as detailed, accurate or long-running as this
one, we are not the first West Coast municipal agency to attempt to more accurately quantify the weights of
organics diverted from curbside collection due to residential backyard/onsite organics management. Following
are two other municipalities in the region that have undertaken to quantify backyard organics diversion by their
single-family households, and comparisons to our findings from this study and previous NSRP studies in 2008 and
2009. We also make a brief comparison to an American nation-wide review of backyard composting programs:
National Backyard Composting Program (1996)12
Seattle Public Utilities (1998)13
North Shore Recycling Program (2008)5 and (2009)8
Township of Langley (2010)14
National Backyard Composting Program (1996)
In 1995, The Composting Council in Virginia, with funding from the United States’ Environmental Protection
Agency, commissioned a nation-wide survey of home composting programs. Data was obtained from 41
programs in the United States and two in Canada (including the Greater Vancouver Regional District). Four of the
study participants were from our bioregion, the coastal rainforest areas of Washington and BC.
Of the 43 study participants, 12 provided measured data yielding an average of 770 pounds (350 kg) per year
composted at home by participating households (it is unstated which programs provided measured data). Home
composting was variously defined, ranging from amounts composted in bins only to a broader definition including
“grasscycling and other organic source reduction methods”. The study concludes that “there is a very high
probability that the true nationwide average is somewhere between 467 lbs (212 kg)/hh/yr and 825 lbs (375
kg)/hh/yr”.
Backyard Composting Undervalued
L Page 34
Seattle Public Utilities (1998): Yard Trimmings
In a presentation summarizing earlier studies and calculations related to the potential yard trimmings (YT)
component of composting12,15, Seattle Public Utilities reported three different estimates for the amount of yard
trimmings that could be backyard composted:
562 pounds (255.5 kg) /year/hh (Figure 4-1)
(Derivation below)
kg/hh/year =
YT placed at curb + YT dropped at depot
(residential & landscapers) + estimates of onsite management
_______________ # households
x
70% (weighted average of backyard compostable content
of yard trimmings collection streams)
x 90% (assumed
efficiency factor)
537 - 722 pounds (244 – 328 kg) /year/hh
self-reported household estimates of number of times
yard waste bin filled ___________
year
x conversion factor
(unstated)
500 pounds (227.3 kg) /year/hh
("non-scientific study of individuals weighing their yard waste") (on Figure 4-1).
Seattle used the first calculation of 562 pounds (255 kg) for their estimates of diversion rates that might be
achieved if yard trimmings were composted in backyards instead of collected curbside.
Metro Vancouver and consequently the North Shore have been basing their estimates of diversion due to
backyard composting on this number since 199416, using 250 kg/bin as a standard factor in diversion calculations.
NSRP (2008 and 2009): Household Organic Waste and Yard Trimmings
In 2008, at an earlier stage in our single-family organics research, the North Shore Recycling Program conducted a
survey of 950 households that had purchased municipally-subsidized Garden Gourmet compost bins within the
previous 10 years4, 5. One of the main objectives of the survey was to generate an initial estimate of the diversion
from curbside that can be attributed to backyard composting. In two separate questions, participants were asked
to report weekly volume estimates of the organics that they composted from both inside and outside the home.
Using food waste and yard trimming density estimates from Michigan7 and Waterloo6, these self-reported
volumetric estimates were converted into weekly weights and then extrapolated to an entire year, in a manner
similar to Seattle’s. These are baseline numbers we have been using for our in-house waste diversion calculations
since 2008 and which we had wished to ‘calibrate’ by way of this study:
Backyard Composting Undervalued
L Page 35
250 kg/hh/year for household organic waste
165 kg/hh/year for yard trimmings
415 kg/hh/year: total organics composted
In 2008 and 2009, following on from our 2008 survey, the
North Shore Recycling Program conducted a series of
pilot programs designed to increase SF organics
diversion. Using the same methodology as for the 2008
survey, evaluation of our personalized compost training
pilot8 (“Compost Coaching”) showed that households
receiving compost training increased their diversion over
the baseline significantly:
370 kg/hh/year for household organic waste
150 kg/hh/year for yard trimmings
520 kg/hh/year: total organics composted
Township of Langley (2010): Food Scraps
In 2010, the Township of Langley undertook “a study to
develop and pilot test strategies to enhance the
municipality’s current backyard composting program, utilizing Community-Based Social Marketing (CBSM)
principles and approaches to effectively foster behavioural change.”14 Thirty-two of their participating residents
weighed and reported the amount of food scraps they put in their backyard composters for a six week period in
July and August 2010. The participants did not record the amount of yard trimmings composted. Two strategies
were employed; “Personal Contact” and “Non-Contact”. The participants who received “a personal level of
coaching and communication” diverted an average of 5.1 kg/week compared to 3.8 kg/week for those in the Non-
Contact strategy. Converting these weekly averages to an annual rate gives:
265 kg/hh/year for the Personal Contact participants; and,
198 kg/hh/year for the Non-Contact participants.
During the same time period, the NSRP volunteers from Studies 1 & 2 (Organics Diversion and Mega Composter)
diverted an average of 5.04 kg/week, virtually the same as the 5.1 kg/week Langley reported for “Personal
Contact” participants.
Comparisons
The average amount of diverted organic waste actually measured during this 2010 NSRP study was 206
kg/hh/year for household organic waste (food scraps + low quality paper waste) and 246 kg/hh/year for yard
trimmings. Figure 4-1 shows a comparison of these results to the latter three studies mentioned above.
Our total organics diverted by composting per household per year (452 kg) is 20% higher than the high end of the
range and 30% higher than the average calculated in the 1996 National Backyard Composting Program study. In
our heavily-treed rainforest ecosystem, the proportion of onsite-compostable organics generated from the yard is
likely higher than the American average. The inclusion of gardening techniques that keep organics onsite (e.g.,
Harvesting Compost
Backyard Composting Undervalued
L Page 36
grasscycling and garden mulching) into our measured diversion rate would further increase the gap between their
calculations and our results.
Figure 4-1: Average annual diversion rates for household organic waste and yard trimmings.
All three of Seattle’s calculated potential diversion rates for yard trimmings are very much in line with our actual,
measured annual diversion rates for yard trimmings. Despite basing all of their late-90s estimates on calculations,
conversion factors, weighted averages and depot tonnages, their estimates were almost the same as our
measured backyard composting of yard waste.
Our earlier attempt in 2008 followed Seattle’s lead in making extrapolations based on what little data we had.
Quantifying backyard organics diversion using self-reported volumetric estimates, conversion factors and
extrapolations was surprisingly close to our actual, weighed measurements for both yard trimmings and
household organic wastes. Although we overestimated household organic wastes and underestimated yard
trimmings, our estimated total organics diversion was only 37 kg under our actual, measured diversion.
Langley’s lower, “non-contact” extrapolation is virtually the same as our actual, measured annual diversion rates
for household organic waste. However, when we compare our data for the same six week period as Langley’s
study, our apparent annual amount diverted from curbside collection calculates to the same as Langley’s higher
number: 262 kg/hh/year. Other than the week after Hallowe’en, most of our participants reported the highest
weights of household organic waste in the months of July and August.
246
165 150
198227
206
250
370
265 255
452415
520
0
100
200
300
400
500
600
NSRP 2011 (with training)
NSRP 2008 (baseline)
NSRP 2009 (with training)
Langley Seattle
We
igh
t (k
g/h
h/y
ea
r)
Comparison of Annual Household Diversion Averages
Yard Trimmings Household Organic Waste Combined
Backyard Composting Undervalued
L Page 37
Only our study has measured the combined total of organic waste composted from both inside and outside the
single-family home, and our measured diversion is almost double the estimate currently used in our Region.
Implications
Comparisons to backyard composting averages for the continental United States likely underestimates
the yard trimmings portion of organics composted onsite in our rainforest ecosystem.
By using data from only July and August, Langley’s annual food scraps diversion estimates may be
artificially high.
Using similar “educated guess” and extrapolation methodology, both Seattle’s and the NSRP’s earlier
estimates are surprisingly accurate.
By using 250 kg/bin/year, Metro Vancouver may be underestimating (by a factor of almost ½) the actual
diversion from curbside collection due to backyard composting.
Curbside Collection Implications
Although it was not a stated objective of this study,
our findings provide insight on changes to the
contents and quantities of the materials placed in the
curbside collection stream by our study participants.
In this section, we explore the implications of results
related to:
Materials diverted from curbside collection
stream
Weekly curbside set-out volumes
Calibration of earlier estimates
Annual quantities kept off the curb
Materials Diverted from Curbside
Collection Stream
According to Metro Vancouver 2009 waste audits, 6%
of the Region’s waste stream (4% on the North
Shore1) – by weight – is comprised of non-recyclable
wrappers, paper plates and cups, tissue paper and
towelling17. Comparing post-study survey results to
our 2008 Composter Follow-up Survey4, 5 baseline
shows that the percentage of households composting
these low-quality, non-recyclable household papers
has dramatically increased over the general
composting population baseline (table 4-1).
Composting non-recyclable papers
and food scraps.
Backyard Composting Undervalued
L Page 38
(n = 15) 20084, 5
Baseline
2010
Post-Study Increase
Paper toweling, tissue, paper napkins 23% 80% 57%
Paper bags, paper towel or toilet paper roll cores 12% 53% 41%
Table 4-1: Percentage of households composting low-quality papers compared to 2008 baseline.
Although not explicitly quantifiable, we know from our autumn “Leaf Exchange”, our post-study surveys and
conversations that the volunteers:
are using more yard trimmings (leaves and grass clippings) as mulch or in large, low-maintenance
compost heaps;
are adding more leaves as “browns” in the compost;
have altered their buying habits to reduce waste at source; and
some are now using private recycling services for materials the NSRP does not collect instead of
throwing material in garbage.
Weekly Curbside Set-out Volumes
Our post-study surveys show that 79% of households reported increasing the amount of material they composted
and the same percentage reported reducing the amount of waste they put in the garbage (figures 3-3 and 3-15).
To determine how the study participants’ weekly set-outs of garbage and yard trimmings (YT) compare to those
of the baseline population, we compare our findings to those of our 2008 Curbside Collection Survey2 in table 4-2.
20082 2010 Decrease
Garbage (Cans) 1.7 0.77 55%
Yard Trimmings (Cans) 1.6 1.18 26%
Table 4-2: Average amount of garbage and yard trimmings put out for collection in 2008 and 2010.
The decrease in weekly set-outs between our study volunteers and the baseline population of composting
households on the North Shore is significant: half a can of yard trimmings and one full can of garbage.
Calibration of Earlier Estimates
In the absence of accurate, measured data, the NSRP had estimated annual per-household weights for materials
composted by households without any compost training4, 5 (250 kg/hh/year of household organic waste and 165
kg of yard trimmings; 415 kg total) and with training8 (370 kg/hh/year of household organic waste and 150
kg/hh/year of yard trimmings; 520 kg total).
Backyard Composting Undervalued
L Page 39
With the results generated from this study, we can now calibrate our earlier baseline estimate of diversion due to
backyard composters (no training) on the North Shore (table 4-3):
Calculated
Estimates4,5,8 Measured Calibrated
With Compost Coaching 520 kg 452 kg -
Baseline (No Training) 415 kg - 361 kg
Table 4-3: Measured and calibrated per household annual diversion rates due to backyard composting.
The calibrated annual baseline diversion for households without training is 361 kg: 144 kg of yard trimmings and
217 kg of household organic waste. With these two numbers, 361 kg and 452 kg, we now have accurate measures
of baseline (no training) and maximum possible (with Compost Coaching) diversion rates of household organics
through backyard composting.
Annual Quantities Kept off the Curb
Using our actual, measured per-household results, we are now able to more accurately estimate the waste
tonnages entirely diverted from the collection stream due to onsite composting by North Shore single-family
homes. Extrapolations of our results to the 2008 composting population of 23,261 households2 are displayed in
table 4-4, and represent weights of materials that the municipalities never need to handle or pay to tip at the
Transfer Station. A brief extrapolation to the number of truck trips avoided is calculated below.
The organic materials managed onsite, had they been placed out for curbside collection, would have been
separated into two different waste streams: household organic waste would be placed in the garbage stream,
destined for disposal at the Cache Creek landfill or Burnaby incinerator; the yard trimmings would be placed into
the Yard Trimmings program, destined for industrial composting at Fraser Richmond Soil and Fibre.
Baseline (2008)4, 5 This Study (2010)
Diverted from
hh/year Total/yr hh/year Total/yr
Household Organic Waste (tonnes)
Collection for Disposal
0.217 5,048 0.206 4,792
Yard Trimmings (tonnes) Collection for Composting
0.144 3,350 0.246 5,722
Total Organics 0.361 8,398 0.452 10,514
Table 4-4: Extrapolated tonnages of waste diverted by SF households that municipalities never handle.
From our study’s findings, we extrapolate that the annual materials kept off the curb by single-family households
is between 8,398 and 10,514 tonnes due to onsite composting. Our original 2008 estimate of 9,600 tonnes fits
neatly into the middle of this range. These numbers only represent backyard composting; our study did not
Backyard Composting Undervalued
L Page 40
attempt to measure yard trimmings handled onsite using other gardening practices such as mulching or leaving
grass clippings on the lawn. Because of these common gardening techniques, the true quantity of organics
generated and diverted from collection by SF homes may be even higher.
The maximum capacity of trucks hauling materials to the transfer station is ten tonnes, but loads average
between six and eight tonnes, depending on the route and material density18. Based on an average of seven
tonnes, it would take 1,500 truck trips to transport all of the organics currently diverted by single-family
households were they to cease composting and leave materials for the municipality to handle through curbside
collection services.
Currently, the North Shore municipalities spend $3,500,000 annually on garbage and yard trimmings collection
services (not including tipping fees)19, 20, 21, about $1,500,000 of which is for yard trimmings only. The upper
estimate of backyard-composted tonnages is approximately equal to the quantity of Yard Trimmings collected
from curbside (10,638 tonnes)18 for industrial composting in 2010.
Implications
We can now use the following numbers with confidence: 361 kg/hh/year for untrained households and
452 kg/hh/year for households that receive compost training.
Backyard composting precludes North Shore
municipalities from handling and tipping up to 10,500
tonnes each year (using 2008 population and survey
data).
Backyard composting prevents approximately 1,500
truck trips on the North Shore each year.
Backyard composting diverts an amount almost
equivalent to the current municipal Yard Trimmings program (which costs $1,500,000 for collection only),
but with virtually no costs to the municipalities.
A significant increase in backyard composting over current levels would create decreases noticeable both
to swampers on collection routes and to managers overseeing collection budgets.
Supported backyard composting can:
remove low-quality (non-recyclable) household papers from the waste stream;
increase the perceived value of yard trimmings as feedstock for healthy compost and gardens;
translate into additional waste reduction activities; and
reduce curbside set-outs by 25% for yard trimmings and 60% for garbage.
Diversion Rate Implications
By definition, a “Diversion Rate” is calculated as follows:
A swamper is a person who lifts garbage and yard trimmings cans and empties them into
the collection truck on service day.
Backyard Composting Undervalued
L Page 41
Although it is a straightforward equation, there are many
variations in calculation method based on the data
available through measurements and estimates.
Because our study results show that actual, measured
‘best-case-scenario’ per-household annual weight being
composted is almost twice as high as the 250 kg number
previously assumed, we will explore the possible
implications of this finding on two calculated diversion
rates:
Metro Vancouver (MV) region
North Shore Single-Family residences
But first, we will address the question of “number of
composters distributed” compared to “number of
households composting”.
Composters Distributed Compared to Households Composting
Our 2008 Single-Family Curbside Collection Survey2 found that there are 23,261 households composting on the
North Shore, 44% more than the 16,208 municipally-subsidized composters distributed by that same year.
Since the 2008 survey and through 2010, the NSRP distributed 903 additional compost bins to total 17,111. If we
apply the 44% increase to this more recent number, we derive a more current representation of composting
households on the North Shore.
Our current estimate of the number of households composting on the North Shore in 2010 is 24,640.
Metro Vancouver’s Waste Diversion Rates
The derivation of Metro Vancouver’s regional waste diversion
rate is a very complex and controversial calculation. Rather
than being in the form of a simple equation, its current
configuration is housed in numerous, complex spreadsheets.
Data to populate the spreadsheets is submitted by or
estimated for: municipalities (curbside collection, depot
services and backyard composter sales); private waste and
recycling processors (commercial, multi-family and
construction material collection, processing and disposal);
Extended Producer Responsibility participants (take-back
tonnages); and MV's transfer stations.
Backyard composters are factored into the regional calculation
Curbside set-out
Extended Producer Responsibility (EPR) is
an environmental policy approach in which
a producer’s responsibility for a product is
extended to the post-consumer stage of a
product’s life cycle. EPR shifts the
responsibility (physically and economically)
upstream to the producer and away from
municipalities and tax-payers and provides
incentives to producers to take
environmental considerations into product
design.
Backyard Composting Undervalued
L Page 42
as follows: each municipality submits the total number of compost bins distributed to residents and that number
is multiplied by 250 kg/bin.
The calculated diversion rate is published in Metro Vancouver’s annual reports. In 2008, the diversion rate for the
entire region was 55% and for the residential sector (which combines single-family and multi-family residences)
was estimated at 46%22. It is important to note that Metro Vancouver’s reported diversion rates are not intended
for performance comparisons between jurisdictions because of variations in calculation method and variability in
source data and estimates.16
Between 1991 and 2008 (the year of Metro Vancouver’s most recent report on regional diversion rates), the NSRP
had distributed 16,208 composters to North Shore residents; this is the number Metro Vancouver used most
recently to calculate residential organics diversion rates (for the North Shore) due to composters17.
Metro Vancouver NSRP Findings
Unit used in calculation Bins distributed by
municipality
Households
composting
Number of Units 16,208 23,261
Diversion per Unit (kg) 250 452
Estimated diversion (tonnes) 4,052 10,514
Table 4-5: Differences between Metro Vancouver diversion rate factors compared to NSRP findings (2008 data).
Our study results show that actual, measured per-household annual weight being composted is almost twice as
high (452 kg) as the 250 kg number previously assumed. Also, the number of households composting exceeds the
number of compost bins distributed by almost one-and-a-half times. The actual diversion due to composters on
the North Shore is more than 2.5 times Metro Vancouver’s estimate.
North Shore Single-Family Waste Diversion Rate
On the North Shore, the tri-municipal, single-family (SF) diversion rate is estimated as follows (measurement
units are tonnes collected curbside or dropped off at the transfer station in the “Residential Drop-off” (RDO)
category). Backyard composters are not currently factored into the equation:
The most recent solid waste statistics available are from 201023, with the exception of the RDO data which is
collected by Metro Vancouver; the most recent RDO data made available to us is from 2008.
Yard Trimmings: 10,638 tonnes
Yard Trimmings RDO: 6,558 tonnes
Garbage: 19,409 tonnes
Recycling: 11,369 tonnes
Backyard Composting Undervalued
L Page 43
Weight per unit Number of Units Kept off curb
(tonnes)
Calculated
Diversion Rate
Not including composting n/a n/a 0 59.5%
Using MV Estimates 250 kg/bin 16,208 bins 4,052 62.7%
Using NSRP Study Findings 452 kg/hh 23,261 households 10,513 66.8%
Table 4-6: Variations in North Shore diversion rate calculations (2010 and 2008 data).
When backyard composters are factored into the equation along with the number of households that compost,
the North Shore’s single-family calculated waste diversion rate increases from the currently-used 59.5% to 66.8%.
If we repeat these calculations using our updated estimate of composting households on the North Shore in 2010
(24,640), the diversion rate using our study findings increases to 67.2%.
Implications
Using the total number of compost bins distributed as a proxy for number of households composting
underestimates the true number on the North Shore and perhaps for other municipalities as well; adding
44% to the number of bins distributed approximates the number of households composting.
The 250 kg/bin/year estimate (derived by Seattle for yard trimmings) doesn’t take into account
household organic waste diversion and underestimates the total quantities diverted by backyard
composting households by almost half.
The actual diversion due to composters on the North Shore is 2.5 times greater Metro Vancouver’s
estimate.
The Regional diversion rate for the residential sector may be higher than currently estimated.
The North Shore’s single-family diversion rate is higher than we have been reporting to municipal staff.
Tipping Fees Avoided
The cost to municipal solid waste utilities for curbside collection services, whether contracted-out or handled by
municipal staff, is not limited to the costs of drivers and swampers and fuelling and maintaining a fleet of heavy
trucks as mentioned above in the ‘Curbside Collection Implications’ section. Fully two-thirds of the garbage and
yard-trimmings collection service costs on the North Shore are in the form of “tipping fees”. These fees are the
charges levied to a municipality for dropping off collected materials – whether for disposal or composting – at
regional transfer stations operated by Metro Vancouver. Each curbside collection stream taken to the transfer
station has a different tipping fee set by Metro Vancouver: in 2010 (2011), yard trimmings cost $59 ($63)/tonne
and garbage cost $82 ($97)/tonne.
All of these costs are offset by the monies collected through the Solid Waste Utility levy assessed on residential
properties. Residential drop-off (RDO) costs are paid by the resident at the time of tipping.
Because our findings show that the average annual per-household diversion rate due to backyard composting is,
in the best case scenario, significantly higher than current estimates, we will evaluate various implications of
these findings as they relate to tipping fee costs:
Fees saved by study
Backyard Composting Undervalued
L Page 44
Fees avoided per average composting household
Total annual tipping fee savings on the North Shore
Cumulative tipping fee savings
Fees Saved by Study
Over the course of the project in 2010, the 25 volunteer households diverted a total of 7,280 kg of organic waste
from curbside pickup. Table 4-7 lists the amount of money saved by their management of organic wastes at the
source.
2010 Tipping Fees
($/tonne)
Total Weight
(tonnes)
Total $
Saved
Household Organic Waste $ 82.00 4.481 $ 367.45
Yard Trimmings $ 59.00 2.799 $ 165.12
Grand Total 7.280 $ 532.57
Table 4-7: Actual tipping fees avoided by the volunteer households in 2010.
A total of $532.57 was saved in 2010 due to the volunteer efforts of the 25 participating households.
Fees Avoided per Average Composting Household
The tipping fees for 2011 are shown in table 4-8 along with the average, measured weights diverted by our study
participants.
2011 Tipping
Fees ($/tonne)
Total Weight
(tonnes) Average/hh/year
Garbage $ 97.00 0.2057 $19.95
Yard Trimmings Feb - Dec $ 63.00 0.2459 $ 15.49
Total Saved $ 35.44
Table 4-8: Average tipping fees that will be avoided in 2011 by households with compost training.
The average tipping fees saved per household managing organics onsite will be $35.44/household in 2011. As
tipping fees in Metro Vancouver increase over time, so too will the fees avoided by the municipality.
Backyard Composting Undervalued
L Page 45
Total Tipping Fees Avoided on the North Shore
Our calculation of tipping fees avoided in the 2011 fiscal year, based on number of households composting in 2008
(23,261)2, is summarized in table 4-9.
2011 Tipping
Fees ($/tonne) # Households Composting2
Average kg/hh/year
Fees Avoided
Garbage $ 97.00 23,261 206 $ 464,801
Yard Trimmings Feb - Dec
$ 63.00 23,261 246 $ 360,499
Total $ 825,300
Table 4-9: Tipping fees avoided by North Shore municipalities due to onsite composting in 2011.
In 2011, the municipal residential tipping fees avoided due to backyard composting will be $825,300, even before
considering new households starting to compost since 2008 numbers were gathered.
We have suggested above that the number of households composting on the North Shore exceeds the number of
composters distributed by 44%. If we use our more current estimate of composting households on the North
Shore (24,640), the total tipping fee savings for 2011 increases to $874,227.
Since 2005, the NSRP has distributed an average of 476 composters per year24, equivalent to 685 composting
households using the 44% extrapolation. At this rate, the annual tipping fee savings due to backyard composting
increases by $24,300 each year, even before taking into consideration any future tipping fee increases.
For single-family curbside-collected materials, the three North Shore municipalities spent $1,500,000 on garbage
tipping fees and over $600,000 for yard trimmings tipping fees in 2010. The tipping fees avoided by the
municipalities due to backyard composting exceed the total tipping fees paid for the curbside yard trimmings
collection program.
Cumulative Tipping Fee Savings
It is important to note that tipping fees avoided by the municipalities is cumulative. Following any initial
investment in composting equipment subsidies and staff time for composter sales, residents will continue to
divert waste and save the municipality collection costs and tipping fees so long as they continue their onsite
composting activities. There is no ongoing or annual cost to continue this benefit and there is a composting ‘drop-
out rate’ of only 10% over a ten year period4.
At the present time, the NSRP subsidizes compost bins by $6.44 and sells aerating tools at cost. Due to staff
shortages, we are not offering any Compost Coaching services to anyone other than door prize draw winners or
donation recipients. Other than the depot staff handling bin sales, no staff time is being directed to supporting
diversion through backyard composting. The annual financial resources going toward supporting backyard
composting in 2011 are in the range of $3,200.
Backyard Composting Undervalued
L Page 46
Over the last five years on the North Shore, we have invested approximately $16,100 in bin subsidies and
backyard composting has resulted in avoided tipping fees (only) of approximately $3,500,000.
Implications
We can now estimate the tipping fee savings experienced by a municipality for each composting
household at approximately $35/year (2011 rates).
Annual tipping fees avoided due to backyard composters are much larger than they are being credited;
$874.227 in 2011 (over one-third of the municipalities’ tipping fee costs) and increasing as more
households start composting and tipping fees increase.
Without training or support, initial investment is very low and ongoing costs are close to nil for status quo
diversion due to backyard composting.
Cumulative tipping fee savings due to backyard composters, over only five years, double the annual cost
of all North Shore SF curbside collection tipping fees and are on the same order of magnitude as major
budget expenditures and capital costs for solid waste handling.
Personalized Compost Coaching
Evaluating the effects of Compost Coaching (personalized, onsite compost training for households) was not the
objective of this study; a pilot program and thorough evaluation were conducted in 2008/09 to directly test this
approach to single-family organic waste diversion8. However, we will summarize below some of the implications
of Compost Coaching combined with the personal support and joint learning events offered throughout the study
that became apparent in our evaluation.
Direct, quantitative participant feedback on Compost Coaching was very positive: all study participants rated their
Compost Coaching experience between “neutral” (4) and “very useful” (7); and 100% of participants recommend
Compost Coaching to others, particularly households new to composting. Qualitative anecdotal feedback on site
visits and training, telephone and email check-ins, e-newsletters, the online community, group events and tours
was extremely positive. The importance of these regular points of contact to volunteers’ success was reiterated by
volunteers and evident in their actions, e.g., despite intense pest issues, all but one Green Cone participant stuck
with the system for the duration of the study and plan to continue its use.
Compared to pre-study surveys, post-study responses showed positive results that may be attributed to Compost
Coaching and readily-available support throughout the year: number of participants with high to very high
confidence levels increased; quantities composted and quality of compost are higher; odour and pest problems
were reduced (except for Green Cone participants); and greater variety of materials were diverted from the
garbage stream to onsite management. Anecdotally, many households also increased their enthusiasm for
finding additional waste reduction methods, implemented shopping and recycling behaviours that resulted in
dramatic reduction of garbage placed curbside; and became waste reduction champions within their social circles,
supporting and exemplifying waste reduction behaviours.
Implications:
Personalized Compost Coaching and support increases residential waste reduction not only through
composting but also through consumer behaviour changes.
Backyard Composting Undervalued
L Page 47
Compared to its low cost of delivery, personalized training services provide immeasurable social and
environmental value beyond the direct tipping fee savings and decreased curbside collection requirements.
Implications of Test Results for Garden Gourmet Alternatives
The NSRP currently subsidizes the Garden Gourmet (GG) compost bin for North Shore residents. Two of the three
objectives of this study were to assess the suitability of two alternatives to the GG that may address some of the
capacity and ease-of-use concerns that were raised during our 2008 Backyard Composter Follow-up Survey4, 5:
Mega Composter
Green Cone
Mega Composter
Five Mega Composters were tested to see if a considerably larger bin with a spring-operated lid and four lower
access doors would address capacity, lid and access hatch concerns.
Feedback related to the initial phases of the testing was positive: the bin was easy to transport in its sales
packaging; assembly of the unit was straightforward; and the flip-top, spring-operated lid (which could easily be
operated with one hand) was much appreciated. However, feedback related to the longer-term usage of the bin
was generally negative: the lower access doors were too small and did not stay closed on their own; the bin did
not maintain structural integrity after months of usage; aeration of a taller bin was more difficult; and the bin was
abnormally susceptible to pests despite proactive management and reactive solutions.
Overall, the bin rated neutral compared to the GG; three of five families would recommend it and only two of five
will continue to use it.
Green Cone
Eight Green Cones (GC) were tested by nine households to assess if this in-ground digester might be a viable
alternative for households that wish to manage food scraps onsite without having to aerate or add high-carbon
materials.
Feedback on all stages of testing was very mixed: although transportation of the GC was easy, finding suitable
sites and installation was very challenging; the top lid was rated highly, but the opening was considered too small
by some; variety of materials diverted surpassed composting, but the GC could not handle the total volume of a
household’s food scraps; ease of use rated highly and there were no odour or bear issues, but there were
surprising lessons in biology (maggots, flies) that tested volunteers’ commitment to the digester. All but one
household dealt with regular and frustrating excavation of the GC’s basket by small wildlife and all households
reported at least one “problem” with the system.
Overall, however, participants testing the GC rated its overall performance as neutral to high compared to
expectations, and despite apparent challenges, seven of nine households will continue to use the Green Cone and
100% would recommend it to others.
Backyard Composting Undervalued
L Page 48
Implications:
Small, moving parts on compost bins are delicate and do not stand the test of time and usage.
A larger bin is not the best way to handle residents’ desire for greater capacity.
The Green Cone is not well-suited to the North Shore, but there may be selected circumstances where it
could serve as either a primary or secondary onsite organic diversion system that is safe in bear country.
Backyard Composting Undervalued
L Page 49
5. Conclusions and Recommendations
Backyard composting is undervalued; it is far more important than we thought. Each year in North and West
Vancouver, between 8,398 and 10,514 tonnes of single-family organic waste is generated by never placed curbside
for municipal collection and disposal. This rivals the curbside Yard Trimmings collection service in diversion
tonnages (10,638 tonnes), but minus all the associated municipal costs (~$2,100,000) and environmental
implications of an industrialized collection and composting system. Without backyard composting, North Shore
municipalities would require an additional 1,500 truck trips to the transfer station, for which they would be
charged $874,227 in tipping fees each year.
While the municipalities put almost $6,000,000 into annual collection services and tipping fees, there is currently
no staff, budget or activated program specifically dedicated to recruiting and supporting households that keep
organic waste off the curb through backyard composting and tangential waste reduction behaviours (other than
~$3,200 in compost bin subsidies).
It is not surprising that North Shore municipal governments are spending millions on collection services and very
little for onsite solutions not knowing the current diversion, related cost savings and diversion potential of
backyard composting.
Now, with measured data revealing the substantial tonnages diverted from curbside collection, the seven figure
magnitude of costs avoided and the derivative social and environmental benefits, a pairing of composter sales
operations and meaningful support for households choosing to compost would be prudent.
The incredible potential of a marriage between compost bin sales operations and targeted, personalized outreach
is a topic for other reports and calculations25, 26, but the following study conclusions and overall recommendations
are a direct result of our research findings within this report.
Based on the research data, survey results, calculations and discussion, the following conclusions are made with
respect to our three studies’ original stated objectives.
Conclusions
This research project initially set out to weigh organics composted per household and to test alternatives to the
Garden Gourmet compost bin. Three concurrent studies were coordinated to achieve these goals, each with their
own specific set of primary objectives. Here are the conclusions we draw for those specific objectives:
Study 1: Organic Waste Diversion
The measured average weight of organics diverted
from curbside collection is 452 kg/hh/year for
households that have received Compost Coaching.
The calibrated annual estimate of organics diverted
from curbside collection is 361 kg/hh/year for
baseline households that have not received any
training.
Organic Waste Diversion Objectives:
refine the per-household annual estimates calculated from the January 2008 Composter Follow-up Survey4,5
more accurately estimate overall diversion rates through backyard composting on the North Shore.
Backyard Composting Undervalued
L Page 50
On the North Shore, between 8,398 and 10,514 tonnes of single-family organic waste is generated but
never placed curbside for municipal collection and disposal, saving municipal utilities $874,227 per year
and almost $3.5 million in the past 5 years in tipping fees alone.
The North Shore Single-Family diversion rate, when including backyard composting, is 67.2%.
Study 2: Mega Composter
The Mega Composter is not durable enough to
handle large volumes of household and yard waste
materials.
Although easy to install and operate initially, the
Mega Composter presented operational challenges
and persistent pest problems.
Study 3: Green Cone Food Waste Digester
Although durable, the Green Cone is not large
enough to handle typical household food waste
volumes.
When not loaded beyond its stated capacity, the
Green Cone is very effective for digesting all types of
food scraps when sited in a well-drained, sunny spot.
Installation was a considerable, but one-time hurdle
that places a significant barrier to success; operation
of the Green Cone couldn’t be simpler when capacity
instructions are followed; although not an attractant
to black bears, the Green Cone was beset by pest
and excavation issues.
The Green Cone is only somewhat suitable for use on the North Shore and then only in very specific
circumstances (right site, right household attitude, lots of available support) and would best be used as a
component in an onsite organics management system that includes backyard composting.
Mega Composter Objectives:
determine if the Mega is durable enough to handle a large volume of material (kitchen waste, low-quality household paper products, and yard waste); and
assess ease of installation, operation and resistance to pests.
Green Cone Objectives:
determine if the GC is durable and large enough to handle typical household food waste volumes;
determine how effective the GC is for all types of food scraps;
assess ease of installation, operation and resistance to pests; and
determine if the GC is suitable for use on the North Shore as a viable alternative or companion to the Garden Gourmet.
Backyard Composting Undervalued
L Page 51
Recommendations
Following on from the study results, analyses and conclusions, we make the following recommendations:
Mega Composter:
Abandon the Mega Composters as a viable option for North Shore residents.
Handle capacity concerns by emphasizing the benefits of a multi-bin system.
Green Cone:
Do not offer Green Cones as a standard alternative to the Garden Gourmet.
Make Green Cones available at a minimally-subsidized rate to qualified North Shore residents but only
with the following pre-requisites established:
o repeat support opportunities are available through Compost Coaching or similar personalized
training and troubleshooting program;
o household has adequate sunshine, drainage and time for installation (create checklist);
o household already composts, using the Green Cone as a component of a more comprehensive
organics management system;
o household is aware and accepting of expected pest challenges (create info sheet); or
o household intends to manage pet waste only.
Consider an at-cost installation service to overcome this barrier for otherwise qualified households.
Compost Coaching:
For prize draw or donations, provide compost bins only with mandatory training and an aerating tool.
Introduce Compost Coaching or similar personalized training and troubleshooting service as a core
support component for all composter sales.
Completely integrate composter sale operations with community outreach functions.
Create multiple access points (phone, email, online, in-person) for residents to learn of and book
Coaching appointments whether for new bin purchases or troubleshooting existing bins.
Build on the strong relationships built with residents involved in this study and past composting pilot
programs to champion, support and possibly staff this new program.
Position program proposal to municipalities as a cost-saving measure with minimal investment (no
capital, low personnel and start-up expenditures), significant carbon-footprint reductions and very
substantial short- and long-term seven figure savings to municipal utilities.
Curbside Collection and Tipping Fees
Recognize annual costs avoided due to composting as a line item in budget summaries and planning
documents to municipal staff.
Commission a focused study on the carbon emissions avoided by current onsite composting and the
potential for further reductions as households shift from curbside collection to onsite management.
Backyard Composting Undervalued
L Page 52
Increase support for onsite composting, the lowest-cost municipal waste diversion tool in the suite of
collection programs which has diversion and cost-saving results disproportionate to its minimal
investment.
Allocate staff and resources to significantly increase the number of composting households, recognizing
that the scale of diversion through onsite composting is on par with curbside Yard Trimmings collection
and that the scale of incremental cost savings will be in the six figure range annually.
Diversion Rates
Include backyard composting in the annual North Shore Single-Family diversion rate calculation, using a
per-household rate between 361 kg and 452 kg.
On an annual or bi-annual basis, collect statistically-significant data on the number of households
composting and usage of composting best practices.
We respectfully suggest that Metro Vancouver consider the following recommendations:
Request that municipalities submit number of households using compost bins derived from statistically
significant surveys, instead of using total number of bins distributed.
Capitalize on the advantage of scale to conduct more economical statistically-significant surveys
determining the number of households composting by municipality and for the overall Region.
Revise the 250 kg per bin factor upwards to between 361 kg and 452 kg per household.
Information Sharing
Present report findings to municipal solid waste staff and councils.
Share study results with Pacific Northwest municipalities and North American solid waste associations
and publications.
Backyard Composting Undervalued
L Page 53
6. Acknowledgments
We would like to acknowledge our wonderful volunteers. Their contribution is invaluable – we could not have
done this project without them. Thank you to all of you and your families for committing to this project for a
whole year:
Kathryn Allison
Nick Bartley
Lawrence Carota
Jim Cathcart
Peter Chappell
Lesley Childs
Lesley Daniel
Mary Delaney
Dan Frketich
Bill Hall
Chris Lofting
Robyn Palliardi
Jennifer Read
Julie Rudd
George Rushworth
Randi Sinclair
Melanie Solheim
John Speers
Judy Stott
Karen Todd
Ruth Tschannen
Karen Vail
Heather Van Halteren
Rosalie Vlaar
Locinne Wallace
We would also like to thank:
Jeff Malmgren of Durable Solutions Inc. for providing Green Cones at a reduced cost.
Jenny Rustemeyer and Grant Baldwin of the Clean Bin Project for their inspiring presentation to the
volunteers.
Tricia Edgar and the staff at the Lynn Canyon Ecology Center for generously letting us use the Center for
our volunteer appreciation event.
Steve Aujla of Fraser Richmond Soil & Fibre Ltd. for his informative tour of their industrial composting
facility.
Ruth Tschannen and everyone at the Cascadia Society for hosting our end-of-summer garden party
lunch and providing tours of their intensive backyard composting systems.
District of West Vancouver for donating a rain barrel for a prize draw.
Mike Stringer (Metro Vancouver), Brian Meslo (District of North Vancouver), Richard Charlton (City of
North Vancouver) and Jennifer Bagby (Seattle Public Utilities) for providing valuable information
through personal communication.
Backyard Composting Undervalued
L Page 54
7. Works Cited
1 North Shore Recycling Program (2009). NS Waste Composition Study [spreadsheet].
2 Points of View Research (2008). 2008 Curbside Collection Survey: North Shore Residents in Single Detached Homes, a Survey Research Report prepared for North Shore Recycling Program, District of North Vancouver, City of North Vancouver, and District of West Vancouver.
3 2009 Curbside Collection Contracts and Municipal Tax Records.
4 Maxwell, S. (2008). Composter Follow-up Report: A Summary of Interviews Conducted in January & February 2008 on use of Composters Sold through the North Shore Recycling Program Between 1998 and 2007.
5 North Shore Recycling Program (2008). Results Analysis and Implications for Community Programs: Supplement to “Composter Follow-up Report, 2008.
6 Regional Municipality of Waterloo. (2000). Backyard Composter Utilization Study.
7 Michigan Recycling Coalition (date unknown). [Yard trimmings and food waste densities].
8 North Shore Recycling Program (2009). Increasing Diversion through Backyard Composting: Coaching Residents New to Composting (A Single-Family Organics Reduction Pilot Program).
9 Green Cone Limited. All about your Green Cone: A Unique Food Waste Digester System NOT a Garden Composter. Instruction Manual.
10 North Shore Recycling Program (2008). “Composting in Bear Country” Guidelines for the North Shore:
Summarized from the final version of “Composting in Bear Country Workshop Outline” (dated November 6, 2008), a
document jointly created by the North Shore Black Bear Society, Bear Aware and the North Shore Recycling Program.
11 www.cleanbinproject.com or www.cleanbinmovie.com.
12 Applied Compost Consulting for the Composting Council (1996). National Backyard Composting Program: Cost-benefit analysis of home composting programs in the United States.
13 Seattle Public Utilities (1998) Measuring Backyard Composting.
Backyard Composting Undervalued
L Page 55
14 Lura Consulting (2010). Township of Langley Backyard Composting Community-Based Social Marketing Study.
Township of Langley.
15 Jennifer Bagby, personal communications, December 2007, January and June 2008 and April 2011. [RE: Seattle diversion estimate calculations].
16 Mike Stringer, Metro Vancouver, personal communications, March 11 and 14, 2011. [RE: MV diversion rate
calculations].
17 Technology Resource Inc. (2010). Metro Vancouver – Solid Waste Composition Study 2009.
18 Colette Scott-Sibley, North Shore Recycling Program, personal communication, May 2011. [RE: average tonnages contained in trucks unloading at transfer station].
19 Brian Meslo, District of North Vancouver, personal communication, May 2011. [RE: 2010 garbage and yard trimmings fleet and salary costs].
20 Richard Charlton, City of North Vancouver, personal communication, May 2011. [RE: 2011 garbage and yard trimmings collection costs].
21 Allen Lynch, North Shore Recycling Program, personal communication May 2011. [RE: 2010 garbage and yard trimmings collection contract costs for District of West Vancouver].
22 Metro Vancouver, “Recycling and Solid Waste Management 2008 Report” (2008).
23 North Shore Recycling Program (2010). Annual Report.
24 North Shore Recycling Program (2010): Composter Sales [spreadsheet].
25 North Shore Recycling Program (2009): Outreach Alternatives to Curbside Organics Collection for the North Shore: Ten Scenarios with Related Cost and Time Estimates.
26 North Shore Recycling Program (2010). Cost and Diversion Estimates [Spreadsheet: Return on investment calculations for sales-integrated Compost Coaching program].