Sustainability & Risk / Green Building / Carbon Footprint - Background Data

Add Wastewater Factors

Wastewater emissions estimate emissions from wastewater collection and treatment systems. Use the Wastewater Factors task to add the protocol you are using for wastewater emission factors. You can then add the wastewater emissions factor data.

Methane emissions from wastewater treatment are determined by how much organic matter is in the wastewater stream. and the conditions under which it decomposes. Wastewater may be treated aerobically or anaerobically. Since aerobic decomposition does not produce methane, while anaerobic decomposition does, the method of treatment is important in determining methane emissions.

The application uses these wastewater factors to calculate emissions for the consumption data you enter on the Waste (Liquid) tab.

To add wastewater emission factors information:

  1. Select Carbon Footprint - Background Data / Wastewater Factors.

    The Define Wastewater Factor Versions, Systems and Data form appears.

  2. To add a protocol version for waste water emission factors:
    1. Click Add New > Wastewater Factors Version.
    2. Enter the following information:

      Version: Enter the name of the protocol version you are using for wastewater emission factors. The Version uniquely identifies this protocol version

      Version Description: Enter a description for the protocol, such as the table number the data is found in, or the year the data is for.

    3. Click Save.
  3. To enter wastewater emissions factor data:
    1. Select the protocol from the drill-down list, and click Add New > Wastewater Factors Data.
    2. Enter the following information:

      Treatment System ID: The unique identifier for this wastewater treatment system. You can mouse over the field to click the Show Values button to select from the existing treatment system IDs. If the system ID is not unique for the factor version, you will need to edit it. You can also enter a system ID manually into the form. See Selecting predefined data for the primary keys for new records.

      Default Percent Anaerobic (%): Enter the percentage of the wastewater for this treatment system that is treated anaerobically. This is obtained from your protocol and is used to calculate methane emissions.

      BOD5/Wastewater. The amount of dissolved oxygen consumed in five days by bacteria that perform biological degradation of organic matter per unit of wastewater.

      BOD5/Wastewater Units: The units used to measure the BOD5/Wastewater. By default, wastewater treatment emissions are measured as milligram of BOD5/gallon of wastewater, but you can define different units if needed. See Defining Units.

      mg CH4/mg BOD5: The measurement of CH4 emissions in relation to a milligram of BOD5.

    3. Click Save.