Last reviewed on 12-01-2023
Documentation of California's Greenhouse Gas Inventory
(2023 Edition - Last updated on 12-1-2023)
♦ Category: Waste
IPCC: |
4D1 - Wastewater Treatment and Discharge - Domestic Wastewater Treatment and Discharge |
Sector: |
Industrial : Wastewater Treatment : Domestic Wastewater : Septic Systems |
♦ Activity: California population -
♦ Greenhouse gas: Methane ( CH4 )
► Year 2017 —
● Greenhouse gas emission estimate —
Amount: |
15,370 tonnes of CH4 Emitted (384,254 tonnes CO2 Eq.) |
Basis: |
Calculation |
Calculation: |
[California Population] * [Proportion in septic systems] * [Septic systems CH4 Emissions Factor] * [Average number of days per year] |
Reference: |
USEPA (2015). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2013. U.S. Environmental Protection Agency. Chapter 7: Waste. http://www.epa.gov/climatechange/emissions/usinventoryreport.html |
● Activity level used in calculations —
● Parameters and Constants used in calculations —
Parameter: |
Proportion in septic systems = 0.1 |
Reference: |
CWTRC, (2003). Status Report: Onsite Wastewater Treatment Systems in California. Jointly presented by: California Wastewater Training & Research Center, California State University Chico and USEPA Region 9 Ground Water Office. August 2003. http://www.csuchico.edu/cwtrc/Pages/InfoandReoprtspage.htm |
Parameter: |
Septic Systems CH4 Emissions Factor = 10.7 g / person / day |
Reference: |
USEPA (2015). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2013. U.S. Environmental Protection Agency. Chapter 7: Waste. http://www.epa.gov/climatechange/emissions/usinventoryreport.html |
Constant: |
Average number of days per year = 365.2425 day |
Reference: |
USNO (2004). U.S. Naval Observatory, Astronomical Applications Department, Leap Years. Accessed online at: http://www.usno.navy.mil/USNO/astronomical-applications/astronomical-information-center/leap-years |
Constant: |
Global warming potential of CH4 = 25 |
Reference: |
IPCC (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K.B., Tignor M., and Miller H.L. (eds.). http://www.ipcc.ch/publications_and_data/publications_ipcc_fourth_assessment_report_synthesis_report.htm |
● Greenhouse gas emitted per unit activity (derived from values listed above) —
Amount: |
391 g of CH4 per person 9,770 g (i.e. 9.77 kg) of CO2eq. per person |