Part 253 for Wastewater
Part 253 is complicated. Wastewater makes it more complicated.
New York’s Mandatory Greenhouse Gas Reporting Program has multiple applicability pathways and source-specific requirements. We help wastewater utilities understand whether the rule applies, why, and what comes next.
Part 253 can reach a wastewater facility in more than one way.
The 10,000 MT CO₂e facility threshold is only one part of the analysis. Wastewater operations can also bring other Part 253 provisions into play.
Facility emissions
Does the plant meet the 10,000 MT CO₂e facility threshold?
Anaerobic digestion and liquid waste
Do wastewater flow or other waste inputs exceed the activity thresholds in §253-2.2?
Combustion and biogas
What emissions from natural gas, diesel, biogas, boilers, engines, and flares need to be counted or reported?
Electricity generation
Do CHP, cogeneration, or other generating units create additional reporting requirements?
Read the current Part 253 rule materials on the NYSDEC website
Part 253 Applicability Assessment
Find out where your plant stands.
The assessment asks plain questions about how your plant operates and checks your answers against the wastewater-relevant Part 253 thresholds and requirements. You do not need to know the regulation to get started.
- Answer questions about your plant
Provide basic information about wastewater flow, anaerobic digestion, waste handling, fuel and biogas use, and onsite power generation. - We check your answers against the rule
The assessment checks your information against the Part 253 provisions relevant to municipal wastewater facilities. - See your result
Receive a facility-specific preliminary result explaining whether Part 253 may apply, the basis for the result, and what to evaluate next.
This is a screening tool, not a regulatory determination.
What happens next
For plants with digesters, reporting may be just the start.
If Part 253 applies through the anaerobic digestion or liquid waste pathway, the facility will also need to determine whether the Emissions Monitoring and Measurement Plan requirements in §253-2.20 apply.
An EMMP changes the compliance task. The facility moves beyond annual emissions calculations to a facility-specific approach for monitoring, measuring, and documenting methane emissions.
- Detecting emissions from digesters, gas systems, flares, storage, and other relevant sources.
- Monitoring over time so measurements account for changing operating conditions and intermittent or infrequent higher-emission events.
- Connecting measurements to operations by reconciling emissions measurements with facility activity and operating data.
- Understanding uncertainty and maintaining the records, calibration, maintenance, and documentation needed to support the monitoring program.
If the EMMP requirement applies, planning early matters. Monitoring methods, equipment, field work, operational data, and documentation all take time to put in place.
Frequently asked questions
Part 253 questions, answered.
Does the 10,000 MT CO₂e threshold determine whether Part 253 applies?
No. It is one applicability pathway. Anaerobic digestion and liquid waste activities can bring other provisions into play.
Does the 700 million gallon threshold apply to every wastewater plant?
No. It belongs to the §253-2.2 anaerobic digestion/liquid-waste pathway, not a general wastewater plant flow threshold. Other waste inputs and combined quantities also matter.
If a plant has anaerobic digesters, does it automatically need an EMMP?
No. §253-2.20 requires a separate check, including whether the facility reports under §253-2.2(a)(1) and qualifies for abbreviated reporting under §253-2.2(a)(2).
What is the difference between a GHG Monitoring Plan and an EMMP?
They are separate requirements. A GHG Monitoring Plan documents emissions-data collection and quality assurance. An EMMP addresses facility-specific methane monitoring and measurement where required.
Does CHP or onsite electricity generation matter?
Yes. It can affect emissions calculations and source-specific reporting requirements. CHP and onsite generation are not equivalent standalone applicability triggers.
What should we do if the assessment indicates Part 253 may apply?
Use your preliminary result to identify what needs further evaluation. Formal analysis, reporting, monitoring plans, EMMP development, agency support, and implementation can be scoped separately with Eddyline; these consulting services are not included in the assessment.
Water-sector GHG expertise
Built around wastewater, not adapted to it.
Eddyline principal David Ponder led development of the Water Research Foundation’s Water Sector Climate Emissions Reporting Guidelines, including guidance for wastewater process emissions, anaerobic digestion, biogas, and direct measurement.
Ready to find out where your plant stands?
Request access below. Eddyline will confirm the assessment option, applicable pricing, and next steps before payment. Talk with Eddyline if you would like to discuss your facility.
Important: The Part 253 Applicability Assessment is a decision-support screening tool. It is not NYSDEC guidance, legal advice, or a regulatory determination. Results depend on the facility information entered, and some circumstances may require additional technical or regulatory interpretation.