Report: Greenhouse gas emissions decrease in Linn County, but not enough

CEDAR RAPIDS — Linn County’s greenhouse gas emissions decreased 3.35 percent between 2010 and 2019, even as local populations and economic sectors grew, a new county report shows. But that progress must ramp up to meet the county’s climate resolution goals by 2030.

The latest Linn County greenhouse gas inventory, released this month, maps the county’s 2019 emissions data and compares it with 2010 baselines. Greenhouse gases trap heat in the atmosphere and make the Earth’s climate warmer. Main contributors include carbon dioxide, methane and nitrous oxide.

The 2019 inventory was completed by the Linn County Sustainability and Resiliency Advisory Committee, a group created in 2021 to develop such inventories annually. The 15 members compiled data from several sources, including commercial, transportation and residential sectors — and fed it through software that calculates emissions.

Emission gains and losses

More than two-thirds of Linn County’s 2019 emissions came from its outsized commercial and industrial sectors — a similar ratio to 2010 baselines. But those sectors also were responsible for the majority of emissions reductions.

Most of the reductions stem from a push away from coal-fired electricity generation that’s occurring on the local, state and national level. Utilities are leaning more on natural gas and renewables, like solar and wind, to fuel the power grid.

In Linn County, for instance, Alliant’s Prairie Creek Generating Station converted some of its generating units from coal to natural gas. Although emissions from natural gas-fired energy increased by 39 percent from 2010 to 2019, total electricity emissions in Linn County decreased 3.66 percent overall, the report found. Iowa’s rapid deployment of wind farms — now generating 62 percent of the state’s electricity — also played a role.

The transportation sector ranked third, producing 15 percent of the county’s emissions in 2019. Those emissions increased 7 percent from 2010 baselines. The majority came from on-road vehicles like trucks and passenger vehicles.

Water and wastewater treatment plants contribute just 3.5 percent of emissions to Linn County’s total. But waste decomposition and other biological processes produce methane and nitrous oxide — more potent greenhouse gases than carbon dioxide.

Those gaseous byproducts, called fugitive emissions, increased by 39 percent from 2010 to 2019 in Linn County. The rise in natural gas usage contributed to that rise as well, as methane is the largest component of natural gas.

Emissions from solid waste that is thrown away — which makes up just 2.23 percent of total county emissions — have increased as well over the period. The increase may be due to the rise in waste at the tail end of the 2008 flood cleanups.

Next steps

The Linn County Climate Resolution, adopted in 2019, established a goal of reducing countywide 2010’s greenhouse gas emission levels by 45 percent by 2030. Another resolution enacted in 2020 prioritizes climate-vulnerable communities like immigrants and refugees, older adults, people with a disability and rural populations.

The county’s reduction in emissions from 2010 to 2019 leaves a significant gap between current progress and the 2030 goal.

Linn County has 10 facilities that produce more than 25,000 metric tons of greenhouse gases, including ADM Corn Processing and Cargill. Most of those facilities have their own goals for reducing emissions. The inventory mapped out how 2030 emissions may look if those goals are adhered to at the local level.

But even then, emissions will fall short of Linn County’s goal. Closing that gap will require 6 percent emission reductions every year until 2030, according to the inventory.

“It means that those industrial companies will have to do more in order for us to achieve the goals that were set by Linn County,” said John Zakrasek, a committee co-chair and a lead author of the report. “Obviously anything the county and citizens can do to help that happen will be highly beneficial.”

Another emissions contributor: agriculture, which constitutes 70 percent of the land use in Linn County. Its impact couldn’t properly be factored into the software, although emissions from off-road diesel usage in agriculture is estimated to have decreased. Future inventories may be able to integrate it into the calculations. For now, the committee included information on practices that can reduce ag emissions, like no-till and cover crops.

Emission reduction can come from other sectors, too, by using gasoline-powered vehicles less, changing building codes, improving energy efficiency, implementing carbon sequestration methods and more.

The 2019 inventory arrives as funding opportunities for climate action increase through recent policies like the Inflation Reduction Act.

“Yes, we do have work to do. But we have more resources than ever before to accomplish that work,” said Tamara Marcus, the county sustainability director and a lead report author. “We can make sure that any kind of planning or implementation we're doing is actually meeting the needs of Linn County residents.”

Brittney J. Miller is the Energy & Environment Reporter for The Gazette and a corps member with Report for America, a national service program that places journalists in local newsrooms to report on under-covered issues.

Comments: (319) 398-8370; brittney.miller@thegazette.com