Reducing waste and improving diversion is an ongoing process. To know whether your zero-waste program is truly effective, it’s essential to evaluate both what’s happening at the operational level and the impact of policies and initiatives.

A waste audit typically measures the types and quantities of discarded materials, providing a snapshot of waste streams. A zero-waste audit goes further, assessing upstream procurement, policies, and stakeholder behaviors to identify opportunities for reduction, diversion, and systemic improvement. This comprehensive approach provides the data needed to make informed decisions, optimize operations, and prioritize investments that deliver measurable results.

1. Evaluating Collection Infrastructure

A zero-waste audit begins with a careful review of collection systems, both front-of-house and back-of-house.

Front-of-House

Inventory and mapping: Identify bin types, placement, and pairings/co-location of streams (recycling, compost, landfill). Are bins consistently branded? Is signage current and clear?

Evaluate necessity and placement: Many institutions, such as universities, have more bins than needed, based on outdated assumptions about littering. A careful review can identify where bins are truly necessary, reducing labor and costs. For example, classrooms may not need individual bins if a centralized collection model is in place, while outdoor gathering areas, like quads or picnic spots, should have bins strategically placed—but not along every pathway.

Custodial arrangements: Organizations are increasingly adopting centralized waste collection, consolidating bins from offices or classrooms into shared stations. This approach reduces labor, cuts costs for bags and sorting, and improves diversion efficiency. For deeper insights and comparative data from higher-education institutions, readers can explore the findings of our Indoor Waste & Diversion at Colleges and Universities survey, which highlights trends in centralized collection and other waste-management practices across 170 campuses.

Back-of-House

Review Hauling Contracts: Are service levels appropriate? Track whether dumpsters are full when emptied, as this often reveals the biggest cost-saving opportunities. If they’re consistently underfilled, you’re essentially paying to throw away air. Adjusting service frequency, reducing bin size, or removing unnecessary bins can save tens or even hundreds of thousands of dollars for large institutions.

Other operational sources: Assess waste beyond public-facing bins, such as grounds, facilities maintenance, dining services, and warehouse/distribution operations to identify opportunities for reduction.

Surplus property: Ensure policies exist to reuse, sell, donate, or repurpose items rather than sending them to landfill.

2. Auditing Procurement and Policies

Upstream activities heavily influence waste outcomes. A thorough audit should review purchasing and vendor policies to understand how procurement affects overall waste management and diversion results:

Is an Environmentally Preferable Purchasing (EPP) policy in place?

Are products durable, repairable, or reusable, and do they contain recycled content?

Do vendor agreements encourage reduced or reusable packaging and take-back systems?

Are policies in place to reduce unnecessary or wasteful purchasing?

Smart procurement helps reduce both landfill waste and the environmental footprint of your purchases.

3. Engaging Stakeholders

Surveys, interviews, and discussions with staff, faculty, or end users provide essential context. Stakeholders can highlight:

Confusion about what is recyclable or compostable

Behavioral barriers that prevent proper waste sorting

Opportunities to improve education, signage, and engagement

Gathering input from those who interact with the waste program daily ensures that audit findings reflect actual usage patterns rather than assumptions. For example, consulting custodial staff or other frontline employees can provide on-the-ground insights to improve collection programs.

4. Turning Data into Insights

A zero-waste audit is only as valuable as the decisions it informs. Key insights from the audit can help your organization:

Identify gaps in collection and contamination issues

Pinpoint opportunities for new material streams or program expansion

Adjust service levels and infrastructure to reduce costs

Inform upstream purchasing decisions to prevent waste at the source

Increasingly, organizations are using technology platforms to collect, organize, and analyze waste data more efficiently. Companies like Z3 Data, WATS, Intuitive AI, Zabble, and Spare-it leverage AI and other tools to turn audit data into actionable insights, helping identify areas for improved diversion, reduced contamination, and optimized operational practices. Integrating these tools with your audit process can accelerate decision-making and improve accuracy across both upstream and downstream waste streams.

5. Benchmarking and Certification: TRUE Zero Waste

For organizations looking to benchmark performance or plan next steps, TRUE Zero Waste Certification provides a proven framework. TRUE certifies buildings or organizations that successfully divert or reduce 90% of waste. Even if your organization isn’t actively pursuing certification, the TRUE methodology is a valuable resource to evaluate reduction opportunities, track progress, and identify actionable steps toward higher diversion rates.

Next Steps:

Once you’ve completed your zero-waste audit and collected both operational and policy data, the findings become the foundation for a strategic zero waste plan, which we’ll explore in Part 3 of this series. A strategic plan takes the insights from your audit and turns them into a roadmap for long-term success, measurable goals, and actionable interventions across the organization.

By grounding decisions in data, incorporating stakeholder input, and leveraging both established frameworks like TRUE Certification and modern technology platforms, your organization can systematically identify waste reduction opportunities, track progress, and implement sustainable practices that drive measurable environmental and operational impact.