HomeMy WebLinkAboutCCWG_Water&WasteMitigating the effects of Waste and
Water Use on Climate Change
A brief overview for the Chula Vista
Climate Change Working Group
Presented by Carla Blackmar
Chula Vista Department of Conservation and Environmental Services
Waste
Methane (CH4) is one of the most potent greenhouse gasses, with approximately 21 times more warming potential per mass than CO2
34% of US methane emissions come from landfills
Methane results from the disposal of biomass (organic waste such as paper, yard waste, food scraps) in landfills
Waste
How to reduce Chula Vista’s methane
emissions?
Capture methane emissions from
County-owned Otay Landfill
Reduce amount of biomass
landfilled in the first place
Waste
At present, 83% of Otay Landfill
methane is recovered and burned to
produce energy
Waste
Burning landfill gasses yields CO2, Nitrous
Oxide, Sulfur Dioxide, VOCs, and
mercury; but the effect of these gasses
on climate change and toxicity is
generally lesser when the landfill gas is
burned than if it were released directly to
atmosphere
In general, however, it would be better if
these gasses were not produced in the
first place
Waste
Reducing the amount of biomass landfilled
(and the amount of landfill gas produced)
can be accomplished by:
o Reducing use of disposable biomass products
o Recycling biomass products
o Composting biomass products
Chula Vista Currently diverts 50% of its waste
stream into recycling and yard waste
collection programs
Waste
Chula Vista’s 1990-2005 GHG
emissions from waste are virtually
null as measured by ICLEI protocol
The 50% diversion rate and 83%
methane capture rate could be
improved, but the effect would not
be measurable in the model we
currently use
Water
Water use impacts greenhouse gas
emissions:
Pumping water uses a lot of energy
in California—approximately 6.5%
of total energy used each year
Increased water use also increases
the amount of wastewater which
must be pumped
Water
Reducing the carbon footprint of
Water can be accomplished by:
o Reducing the distances water must
be pumped
o Using less water
Water
Reducing the distance water must be
pumped requires re-use of
municipal wastewater
Currently the Eastlake/ Otay Ranch
area are plumbed to take advantage
of wastewater recycling
Wastewater from South Bay Water
Reclamation Plant is purchased for
use in these areas
Water
Reducing the amount of water used
requires conservation
Jurisdiction: Otay and Sweetwater
Authorities
Importance of integrated
conservation approach between City
and Water Authorities
Wastewater
Wastewater treatment plants can release
greenhouse gasses into the atmosphere
An anaerobic digester can convert these
gasses into methane, which can be used
to generate power
Chula Vista’s wastewater is processed at
the Point Loma Wastewater Treatment
facility, where captured methane provides
electricity to plant, and for sale back to
grid
Energy required to pump wastewater also
results in GHG emissions