Methodology in Northumberland County’s Segregated Glass Collection Pilot


The pilot took place along two 100-home routes within the town of Cobourg from September 25, 2018 to March 26, 2019. Prior to and during the project, households within the pilot area were delivered the required information to participate in the program, as well as a 16-gallon yellow glass collection box. To optimize collection efficiencies, residents were encouraged to only put the box out when it was at least half full.

For 10 weeks out of the pilot duration, the route driver provided a count and visual analysis on the yellow boxes set out for collection. In addition to driver observations, the pilot included two 50-home curbside waste composition studies (one pre-pilot and one mid-pilot) and four route analyses, completed by project staff.

Key findings  

The project resulted in several high-level findings, which are summarized below:

  • Resident participation was consistent throughout the pilot period. Each week, approximately 10% of yellow boxes were placed at the curb for collection.
  • 90% of glass put out for recycling was put in a yellow box. The remaining 10% was set out for collection in the bagged single-stream recycling.
  • During the baseline waste audit in September 2018, glass represented 7.4% of the recycling stream. In the February 2019 audit, it had increased to 21%
  • Participants stated consistently that they only put their yellow box out every 4-6 weeks, when they were approximately ½ to ¾ full.
  • Over the course of the project, the contamination found in the glass set-out boxes was minimal and consisted mostly of plastic straws in bottles.

From a diversion standpoint, the study found that collecting glass segregated at the curb will increase glass diversion and reduce residue in the form of mixed broken glass (MBG) at the MRF. This glass can then be used for bottle to bottle recycling applications. The financial analysis however found that potential savings that could be achieved from the increased value of the glass may not exceed the increased capital and labour costs associated with this type of collection. It should be noted potential savings through reduced wear on MRF equipment and contamination of other marketed commodities, was not factored into these calculations. Table 1 below highlights the estimated cost increase.

Calculations for Estimated Collection Cost Increase for Segregated Glass
Average estimated current stop time (seconds)20
Estimated incremental stop time increase17%
Glass compartment capital cost/yr. amortized over 7 years x 9 trucks$25,714.29
Current cost per stop$68.64
Incremental stop cost increase due to labour (assume 30% of stop cost)$3.50
Incremental stop cost increase due to capital$0.66
Estimated new stop cost$72.80
Household/stop count39,166
Current estimated annual cost$2,688,354.24
Estimated new annual cost with segregated glass collection$2,851,149.53
Estimated annual cost increase$162,795.29
Glass Revenue/Surcharge Calculations
*Figures in TonnesSurchargeHaulageGlass clean-up TonnageTotal
Current cost$40$45$130646$138,890
Potential cost (collected segregated)$-10$45646$22,610
Estimated annual savings$116,280

Conclusions

While the debate over single versus multi-stream collection continues, this pilot concluded that segregated glass collection is an effective method of collecting a clean stream of mixed glass but that doing so comes at a cost. As the Province moves towards transitioning the Blue Box Program to a producer responsibility system, the potential benefits of separating out problematic materials for segregated collection is expected to be a key point of consideration.

For more information:

For more information on this project please view the project report or Dan Orr at Northumberland County.