Science Inventory

Municipal gravity sewers: an unrecognised source of nitrous oxide

Citation:

Short, M., A. Daikeler, G. Peters, K. Mann, N. Ashbolt, R. Stuetz, AND W. Peirson. Municipal gravity sewers: an unrecognised source of nitrous oxide. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, Netherlands, 468-469:211-218, (2014).

Impact/Purpose:

To estimate N2O emission ranges for municipal sewers, to aid in GHG emission partioning in wastewater management.

Description:

Nitrous oxide (N2O) is a primary ozone-depleting substance and powerful greenhouse gas. N2O emissions from secondary-level wastewater treatment processes are relatively well understood as a result of intensive international research effort in recent times, yet little information exists to date on the role of sewers in wastewater management chain N2O dynamics. Here we provide the first detailed assessment of N2O levels in the untreated influent (i.e. sewer network effluent) of three large Australian metropolitan wastewater treatment plants. Contrary to current international (IPCC) guidance, results show gravity sewers to be an important source of N2O. Results from the monitoring program revealed hydraulic flow rate as a strong driver for N2O generation in gravity sewers, with microbial processes (nitrification and possibly denitrification) implicated as the main processes responsible for its production. Results were also used to develop a robust emission factor for N2O in the context of municipal gravity sewers. Considering the discrepancy with current IPCC Guidelines, further work is warranted to assess the scale and dynamics of N2O production in different sewers elsewhere.

URLs/Downloads:

j.scitotenv.2013.08.051   Exit

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Product Published Date: 01/15/2014
Record Last Revised: 12/19/2014
OMB Category: Other
Record ID: 296862

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LABORATORY

MICROBIOLOGICAL AND CHEMICAL EXPOSURE ASSESSMENT DIVISION

IMMEDIATE OFFICE