Diversion from Landfill: How to Evidence Performance Evaluators Believe

You have been diverting over 95% of collected waste from landfill for three years. The numbers are strong. The sites are certified. The data exists.

Then you open the tender and find a question like this: "Demonstrate your organisation's track record in achieving high diversion from landfill rates and explain how you will maintain or improve performance under this contract."

And the response your bid team drafts says something like: "We are committed to achieving the highest possible diversion from landfill rates, with a current group-wide diversion rate of 96%, and we will work collaboratively with the Council to maximise recycling and minimise residual waste."

That response will score Level 2 out of 4. Maybe Level 1.

The numbers are real. The performance is real. But the evidence is not there — and evaluators can only score what they can verify.

Waste diversion hierarchy infographic showing recycling, composting, energy recovery and residual disposal pathways

This guide is for waste sector bid managers who already know their performance is strong but keep losing marks on the evidencing section. It explains what evaluators are testing, which data sources they accept, and how to structure a response that scores at Level 3 or 4.

What Evaluators Are Actually Marking

Before diving into data sources, it helps to understand the mental model an evaluator brings to a diversion question.

Most evaluators are not waste specialists. They are procurement officers or sustainability managers who have been handed an evaluation framework and told to score responses against it. They are looking for three things:

1. Verified historical performance — not claimed performance, but performance they can trace to an independent source
2. Credible forward methodology — a realistic explanation of how you will achieve or improve the rate on this specific contract
3. Risk mitigation — what happens to the diversion rate when something goes wrong (contamination, market collapse, facility outages)

The word "believe" matters. Evaluators have seen hundreds of responses claiming 95%+ diversion. Many of them were exaggerated, contract-specific cherry picks, or based on definitions that would not hold up under scrutiny. A response that anticipates this scepticism and answers it with traceable evidence earns trust. Trust converts to marks.

The Diversion Rate Definition Problem

The first thing your response needs to do is define what you mean by diversion from landfill.

This sounds obvious. It is not. Different operators use different methodologies. Evaluators know this, and a failure to define your method is a red flag.

There are three common definitions in use across UK contracts:

Your response should state clearly: "Our diversion from landfill rate is calculated as total waste processed minus waste disposed of to permitted landfill sites, divided by total waste processed. This definition includes recycling, composting, anaerobic digestion, and energy recovery, and excludes rejects from materials recovery facilities sent to EfW or landfill."

One sentence. Then move to the numbers.

Accepted Evidence Sources

This is where most bid teams lose marks. They cite their own internal reporting and expect evaluators to accept it.

Internal data is not sufficient as primary evidence for a public sector tender. It can support your case. It cannot anchor it.

Tonnage tracking flowchart showing collection, sorting, processing and disposal reporting chain

Evaluators looking for diversion evidence will typically accept the following sources, roughly in order of credibility:

Environment Agency Waste Returns (Waste Data Interrogator)

The most credible source available for permitted facilities. The EA's annual Waste Data Interrogator publishes site-level data for all permitted waste management facilities in England. It shows inputs, outputs, and management routes.

If you operate permitted facilities, reference your EA permit numbers, the relevant Waste Data Interrogator dataset, and the specific diversion figures it contains. This is independently verifiable. No evaluator can argue with it.

WasteDataFlow Returns

For local authority-controlled waste (household collection, bring sites, HWRCs), WasteDataFlow is the official reporting system. If you are operating or have operated under an LA partnership, your performance will be visible in WasteDataFlow.

Quote the contract reference, the reporting period, and the diversion figures from WDF. Offer to provide extracts or a contract reference that allows the evaluating council to verify directly through the WDF portal.

Environment Agency Compliance Audit Reports

If you have had compliance audits under your waste management licence or environmental permit, the audit outcomes are contemporaneous evidence of your operating standards. An audit that confirms accurate tonnage recording and appropriate waste routing is strong supporting evidence for your claimed figures.

Third-Party Certified Weighbridge Data

Weighbridge tickets from permitted facilities are contemporaneous, timestamped, and auditable. Not all evaluators know to ask for this, but including a summary of your weighbridge data coverage (the percentage of your waste streams that pass through certified weighbridges) adds significant credibility.

Material Facility Data (for dry recyclables)

If you operate or use a Materials Recovery Facility, the output data from that facility — segregated by material type and end destination — is some of the most granular diversion evidence available. Particularly valuable for questions that distinguish recycling rates from overall diversion rates.

Client References and Contract Performance Reports

Existing client performance reports from comparable local authority contracts are useful supporting evidence. Not primary evidence — evaluators cannot independently verify the figures — but a named council contact who can confirm a 94% diversion rate on a five-year contract carries more weight than a bare claim.

Structuring the Case Study Section

Most diversion questions ask for a case study alongside the headline performance data. The case study is where bid teams most consistently undersell their performance.

A weak case study reads like this: "On our contract with [Council], we achieved a diversion from landfill rate of 94% over the contract period through a combination of kerbside recycling, food waste collection, and residual treatment at our EfW facility in [location]."

That is a description, not a case study. It tells the evaluator what happened. It does not tell them why, what the challenges were, or what you would do differently on their contract.

A strong case study answers five questions:

Two to three pages for a case study of this depth is appropriate. One page with vague claims is not.

The Methodology Section: Scoring Beyond History

Historical performance gets you to Level 2. The methodology section is where Level 3 and Level 4 responses are written.

Evaluators understand that your past performance was on different geographies, different contract terms, and different waste streams. They want to know what your plan is for their contract specifically.

Evidence audit trail process map showing weighbridge data, EA returns, third-party audits and MRF data

Your methodology response should address:

Common Scoring Mistakes

Having marked responses across multiple waste tenders, these are the patterns that consistently cost bid teams marks:

Building a Credible Evidence Appendix

The main response body makes claims. The appendix makes them verifiable. Here is what a strong diversion evidence appendix typically contains:

• EA Waste Data Interrogator extracts for your key permitted facilities, with the diversion figure and management route columns highlighted
• WasteDataFlow summary outputs for comparable LA contracts, with contract name, period, and rate
• Weighbridge data summary (not every ticket, but a summary showing coverage and methodology)
• MRF output certificates from key processors confirming end destinations
• Client reference contacts for the two or three case study contracts
• Facility permit numbers for the treatment chain you plan to use on the contract

Keep it organised. Label every document. If an evaluator cannot find the data you referenced in the body within 30 seconds of opening the appendix, it will not be scored.

The Contamination Question

Almost every diversion question in a household collection tender includes a sub-question about contamination management. Contamination is the single biggest practical driver of lost diversion, and evaluators know it.

A strong contamination response covers:

Performance Data: What Numbers to Present

Council waste tender evaluation scorecard with diversion criteria and mark allocations

When presenting diversion performance data, structure it clearly:

Diversion from landfill performance data chart showing improvement trend against contract targets

How mytender.io Can Help

Writing a strong diversion from landfill response requires assembling performance data from multiple systems, structuring it in a way that is both credible and readable, and tailoring the methodology to the specific geography and contract requirements. It is 35 to 50 hours of work for a single question set if done well.

If you want to see what live waste management opportunities look like before the deadline, the Tender Finder is free to use and searches across Contracts Finder, Find a Tender, and devolved nations portals daily.

Summary

Diversion from landfill is one of the highest-weighted technical criteria in council waste contracts. Bid teams who consistently score Level 3 and above do five things:

1. Define the metric explicitly before quoting any figure
2. Anchor historical performance in independently verifiable sources (EA returns, WasteDataFlow, weighbridge data)
3. Separate contract-specific performance from group-wide claims
4. Write methodology responses tailored to the contract geography and waste mix, not generic process descriptions
5. Build a cross-referenced evidence appendix that makes verification straightforward for a non-specialist evaluator

The performance gap between a Level 2 and Level 4 response is rarely about the underlying performance. It is almost always about how that performance is evidenced and explained. If you are diverting 94% from landfill and scoring Level 2, the problem is the response, not the operation.