Household Recycling Code of Practice: Consultation document

3. Residual waste capacity

Residual waste is waste treated through landfill and incineration.

3.1 What the Code proposes

The Code sets out an expectation of a maximum effective capacity of 60L per week for residual waste for kerbside households with their own bin. The Code does not set out expected frequency of collections or bin sizes. This could be achieved by, for example, collecting a 120L bin fortnightly or a 180L bin every 3 weeks or 240L every 4 weeks.

The Code does not expect this maximum capacity to apply to:

• households that do not receive a food waste collection, or
• communal properties or households that use shared bins as there is no reasonable mechanism to ensure that households receive a fair share of residual waste capacity

Local authorities should have a system of exemptions for individual households which unavoidably generate more residual waste, such as large families or those with medical requirements.

The consultation asks you to consider if a maximum effective capacity should be included in the Code, and if so whether this should be set at 60L, 70L or 80L per week.

3.2 Impact of the proposed change

Reducing residual waste capacity is one of the most effective ways of encouraging households to make better use of recycling and food waste collection services available to them, and so send less waste to landfill or incineration. A study in 2015 of UK local authorities found that recycling rates were 7.2% higher when residual waste capacity was halved from 240L per week to a 120L per week capacity.^[17]

The impact analysis of different residual waste capacities being operated by local authorities in Scotland showed a similar trend. The top five performing local authorities in Scotland in 2023 for kerbside recycling rate (i.e. not including communal properties which would not be subject to the restriction) all operated residual waste capacities between 60-80L (see Table 4 below).^[18]

NB: Fife and Falkirk councils achieved higher recycling rates overall, but when yield from communal properties is excluded the above were the highest performing.

As weekly residual waste capacity is reduced, more recyclable waste is recycled rather than being disposed of in residual waste. Analysis indicated that 60L effective weekly capacity achieved the best kerbside recycling rates on average, as can be seen in Figure 1 below. Note that this is based on a small sample of three local authorities; four now operate this system. Effective weekly capacities of 70L and 80L were associated with similar levels of improved recycling rate to each other.

Figure 2 below shows how reduction in residual waste capacity also increases the capture rate of food waste. Capture rate measures the proportion of material generated by households that is successfully collected for recycling. It indicates how effectively residents are separating recyclable materials from their general waste, and how much recyclable material is still being disposed of in residual waste. A higher capture rate means more recyclable material is being recovered and less is being lost in residual waste.

Reduced collection frequency results in reduced collection costs, and lower residual waste volumes mean fewer return trips to the depot, making for more efficient collections. This may reduce expenditure or enable collection crews to provide collections of alternative recyclable materials.

Local authorities also pay a fee to landfill and incinerator operators to dispose of each tonne of waste. Reduced residual waste volumes would reduce local authorities’ liability to pay gate fees that can fluctuate significantly. A large part of the operational savings discussed in the section above on Impacts of the Proposed Measures in the Code are derived from these changes.

3.3 The extent of change required by local authorities to align with the Code

Table 5 sets out the current residual waste systems operated by local authorities in Scotland.

To summarise:

• 23 local authorities already provide an effective weekly capacity of 80L or less
• 9 local authorities already provide an effective weekly capacity of 70L or less
• 4 local authorities already provide an effective weekly capacity of 60L or less

As Table 4 above indicates, several local authorities in Scotland have already limited residual waste capacity and seen improved recycling and reductions in residual waste. Table 5 shows how some local authorities limit residual waste through bin size and collection frequency. The Code does not recommend a specific size of bin or frequency of collection. Recommending a maximum average weekly capacity is intended to avoid local authorities having to replace a large number of functional bins to change their size. Instead, the capacity can be achieved by varying frequency of collection.

3.4 How co-design arrived at this proposal

Stakeholders supported the principle of maximum recommended residual waste capacity being set out in the Code, though there were differing opinions on the appropriate level and some concerns about specific situations.

There was a clear preference for capacity-based recommendations over collection frequencies. Suggested ranges clustered around 60–80L, with an overall preference for a 60L cap. There was discussion of setting a higher initial capacity with a timeline for reducing it. However, local authority waste managers indicated that successive changes are unpopular with the public and that stability helps ensure clear understanding and therefore improved interaction with waste and recycling services.

Stakeholders also expressed a preference for the recommended threshold to minimise the need for new bins. A 70L limit would better align with current bins in use in Scotland than 60L (see Table 5 above and further discussion below).

Some stakeholders suggested that lower residual waste capacity may increase contamination of recycling bins and fly-tipping, or see greater amounts of residual waste going to household waste recycling centres. There were also concerns about the difficulty of implementing lower capacities in communal, rural, or island areas where kerbside collection services may not be available. The Code does not suggest residual waste capacity restrictions for shared or communal bins, but no evidence was presented that the proposal was otherwise more difficult to implement in rural areas or on islands for the specific kerbside properties it is orientated towards.

Some stakeholders flagged the need for flexibility for households with special circumstances (e.g. large families, high nappy volumes, or medical needs) which the Code accommodates.