Waste Composition Analysis for a Local Authority in Transition

A recent analysis for West Northamptonshire Council gave us the perfect opportunity to demonstrate the power of our uniquely multi-layered approach to WCA.

The data provided will enable this group of legacy councils to come together under one unitary authority to provide a unified waste and recycling system for the residents of West Northamptonshire.

The Client

West Northamptonshire Council is a new unitary authority formed from three former district and borough councils. Each legacy council has its own waste and recycling system:

• One is outsourcing its waste management to Veolia
• One is using a combination of in-house and external contractors
• The third is providing a full, in-house service.

As a result, residents were receiving different services across the area. The new council needs to bring all services together to create one unified service for the whole area.

The Challenge

The council wants to bring three legacy systems together into a single, fair service, understand what residents are currently putting in their bins and see how well existing recycling services were being used.

They also need to prepare for upcoming national changes such as Simpler Recycling, Deposit Return Scheme, Extended Producer Responsibility and the UK Emissions Trading Scheme.

Until now, decisions had been based on historic data and day-to-day operational experience. With current contractor contracts due to expire in 2028, what they needed was clear, up-to-date evidence. They wanted answers to simple but important questions:

• How much recyclable material is still going into the general waste bin?
• Are residents in different areas behaving differently?
• What is really in the black bags arriving at the Household Waste Recycling Centres?
• Where should the council focus its campaigns and investment over the next decade?

In early 2024, West Northamptonshire commissioned Integrated Skills to carry out a full Waste Composition Analysis (WCA) across the area.

Project Aims

The brief was clear. Integrated Skills was asked to provide up-to-date composition data for residual (general) waste from:

• Standard kerbside properties.
• Flats with communal bins.
• Three HWRC sites.
• An additional ad-hoc communal recycling sample.

The deliverables included detailed data tables in Excel, a clear report explaining the findings, an estimate of how much material could have been recycled using existing services and a first look at what Simpler Recycling, DRS, EPR and ETS might mean for the council.

Using Socio-Economic Data to Design the Sample

Rather than picking a few “typical” streets, Integrated Skills uses the latest national socio-economic data (ONS Output Area Classifications, or OAC) to design the sample.

These OAC “supergroups” describe neighbourhood types such as:

• Retired professionals.
• Suburban and peri-urban families.
• Low-skilled migrant and student communities.
• Ethnically diverse suburban professionals.
• Baseline UK and semi-/un-skilled workforce areas.

By mapping West Northamptonshire’s profile and then mirroring it in the sample (around 250 households), the project provided a small but robust snapshot of the whole authority, similar in principle to an election exit poll.

This is one of Integrated Skills’ key strengths: combining mapping expertise with waste data so that a modest sampling exercise can truly reflect the wider population.

On-the-Ground Collection

Over one week in February 2024, an Integrated Skills field team collected residual waste samples on normal collection days, ahead of the council’s crews.

For each sample area they:

• Recorded which households had set out bins and how full they were.
• Collected the contents into labelled bulk sacks.
• Delivered the sacks to a dedicated sorting area at SUEZ’s Brackmills Transfer Station in Northampton.

Residents who asked about our activities were given a council-branded letter explaining the project, linking to further information on the council’s website.

A New Way of Looking at HWRC Waste

Traditionally, many waste composition projects at HWRCs focus on a small, very detailed sample (for example, half a tonne), sorted item by item.

We took a different view.

From speaking to council officers and site staff, we knew that managers didn’t want fine detail on a tiny sample alone – they wanted to understand the whole load. So, for West Northamptonshire we used a two-step method at each of the three HWRC sites:

1. Whole load “walkover” assessment

• The full container was weighed.
• The load was tipped out in a safe area.
• Experienced staff walked the pile and estimated the proportion of broad material types by volume (for example, black bags, furniture, textiles, wood, metal).

2. Targeted black bag analysis

• A set number of black bags were opened and sorted.
• The team focused on the key unknown: what was inside the bags that staff could not see on site.

This “broad picture plus targeted detail” approach is simple but powerful.
It gives managers the insight they actually need:

• How much of the HWRC residual stream is still typical household rubbish that could have gone in the kerbside bin.
• How much is recyclable material (such as textiles, WEEE, wood or metal) that could have been diverted if residents had been guided at the point of disposal.

Materials were sorted into 13 primary categories and 64 sub-categories agreed with the client, weighed and the data entered into prepared spreadsheets. This gave a detailed picture of the make-up of a “typical” residual bin, expressed as both percentages and kilograms per household per week.

What the Analysis Revealed: Household Residual Waste

Our analysis showed that West Northamptonshire residents with kerbside collections are setting out a moderate amount of residual waste each week. More importantly, over half of what is in the average general waste bin could have been recycled using existing services at the kerbside or at HWRCs.

The single biggest opportunity is food waste. Even though the council already provides a weekly food waste collection, food still makes up a large share of the residual bin by weight.

Other key findings included:

• A significant share of plastic film and bags in residual waste. These are not yet collected at the kerbside but will become a required stream under Simpler Recycling by 2027.
• Good capture of some core recyclables, but room for improvement in materials such as plastics, glass and metals.
• Different patterns across socio-economic groups, which will help to target education and behaviour-change campaigns.

The study also looked at areas on fortnightly and three-weekly residual collection cycles. Set-out rates were higher where collections are three-weekly, and bins were typically fuller when presented. This suggests that collection frequency, and how it is communicated, has a real impact on how residents use the service.

Flats and Communal Bins

The project included an equivalent of 100 households on communal residual services across three locations. These samples produced more residual waste per household than the average kerbside property and contained:

• High levels of recyclable materials.
• A strong presence of food waste.
• Items such as textiles and small electricals that could be diverted with better on-site options.

An additional communal recycling sample was also analysed. Although the total weight was modest, the level of contamination was high. For the council, this confirmed that flats and communal systems need specific attention. This may include clearer signage, more tailored communications and reviewing bin design and placement.

HWRC Sites

At all three HWRCs, the broad walkover plus targeted black bag method gave a clear picture of what is really in the residual stream. Across the sites, the team found:

• A substantial proportion of black bag waste.
• Many items that could be accepted in other on-site streams, such as textiles, furniture, wood, metal and building waste.
• Black bags that, once opened, contained mostly normal household rubbish, as well as textiles and DIY waste that could have been separated.

For site managers, this insight can help shape layout and signage on the ground, staff training and “front-of-house” conversations with residents, and future decisions about charging, restrictions or targeted campaigns.

Future-Proofing

As part of the project, Integrated Skills used the data to provide an early view of how new national policies might affect West Northamptonshire. Using the sampled data, the report explored:

• DRS: How many drinks containers are still in residual and communal waste, even though these may eventually fall under a deposit system.
• Simpler Recycling: How much plastic film might be added to household and communal collections once this becomes mandatory.
• EPR: What proportion of the residual bin is made up of packaging that will fall under the new producer funding scheme.
• ETS: An indicative range of potential annual carbon costs for fossil-derived materials in the residual stream, using current and possible future carbon prices.

These policy-focused sections do not give final answers, as Government guidance and timelines are still developing, but they give the council a clear sense of scale and the areas where action will matter most.

Turning Evidence into Action

The WCA project has given West Northamptonshire Council:

• A current, statistically robust picture of residual waste from houses, flats and HWRCs.
• Clear evidence that a large share of material in the general waste stream could be recycled or composted.
• Insight into how different neighbourhoods and tenure types behave.
• A practical method for understanding HWRC black bag waste and where on-site interventions can make the biggest difference.

The findings are already helping the council shape its future strategy as it brings three legacy systems together into one.

Planned and potential actions include:

• Reviewing the frequency of services across the new authority area.
• Reviewing the routing of multiple services (we are pleased to be supporting this venture)
• Strengthening food waste communications to make better use of the weekly service.
• Targeting flats and communal areas with clearer guidance and more tailored solutions.
• Adjusting HWRC site management to reduce black bag disposal of recyclables.
• Building a stronger evidence base for funding discussions under EPR and for planning ahead of ETS.

The data provided has already led to a highly successful scheme regarding textile recycling. There was a surprising level of textile material found in the black bag analysis, and the council are already tackling this head-on.

An arrangement with a local firm has made it possible for residents to book collection slots for textiles to be collected at kerbside. This began in April 2025 and uptake has been steadily increasing – no doubt encouraged by the company’s commitment to donating £90 to resident-selected local charities for each ton collected.

The Client’s Perspective

Vanessa Kelly, Waste Services and Projects Manager at West Northamptonshire Council, summed up the value of the project:

“In order to harmonise the service provided to our residents, we needed an in-depth Waste Composition Analysis to further our understanding of the various waste streams created by different areas of the community.

Having worked with Integrated Skills for nearly twenty years we knew they were the right choice. The team were fantastic; overcoming some data issues by speaking directly to residents, working like a well-oiled machine to meticulously separate and analyse the waste.

Their analysis included the contents of the black bags (a rarity in the sector), and this information was absolutely key. It informed how we move forward in a way that a basic WCA never could.

I can’t recommend them enough; lovely to work with, great at what they do and the services they offer are based on a deep understanding of what local authorities need.”