There are opportunities to expand on emissions measurements of wastewater infrastructure. WWTPs with anerobic digesters -which are used to treat sludge and capture CH4 for sale, on-site use, or destruction -merit further attention. The studies identified anerobic digestors as a potential notable source of fugitive CH4 . Thus, using measurement as a tool to determine if this is a widespread issue and root cause may improve the reliability of rate estimates and inform emissions reductions from WWTPs. There are also contrasting results in characterizing CH4 emissions from sewers; targeted study to reduce uncertainty in sewer emissions estimates and ranking of their importance to total city-level emissions is warranted. Last, other wastewater infrastructure with potential to emit CH4 such as biosolids lagoons and lift and pumping stations are not well characterized; future research could address these knowledge gaps.