Why Iowa Overturned its Ban on Landfilling Yard Waste

The battle over where to put yard waste continues, with several states overturning or trying to overturn decades-old bans on yard waste in landfills.

Iowa is the latest state to overturn its ban, with a new law that took effect July 1 that permits yard waste to be disposed of in landfills that have a system in place for collecting gas to turn into energy.

The Iowa yard waste ban was implemented in 1991 due to arguments that landfill space was shrinking. An attempt to overturn the ban was vetoed in 2003 by Gov. Tom Vilsak, who cited continued concerns about landfill space at that time.

But the law passed this time around at the urging of Metro Waste Authority, according to Iowa legislators. Metro Waste operates the state’s largest landfill, Metro Park East near Des Moines.

Sending yard waste to the landfill instead of composting facilities could reduce annual greenhouse gas emissions at Metro Waste Authority by 11 percent, according to a study commissioned by Metro Waste and conducted by SCS Engineers. That reduction would come through a reduction in the number of collection vehicles needed for both household and yard wastes, and through using gas capture technology to harvest the byproduct of the decomposing waste for energy.

Metro Waste nearly doubled the waste-to-energy methane recovery capacity in 2014 at the Metro Park East—which received about 18 percent of the state’s total waste. That waste alone could power more than 11,000 homes, according to the report, and Metro Waste Executive Director Reo Menning says that number could rise to nearly 18,000 homes by 2035 if more yard waste is sent to the landfill.

The move could also result in the shutdown of the Metro Compost Center, which receives nearly 35,000 tons of yard waste each year, selling about 12,000 tons of compost annually.

The change is also expected to save up to $2 million per year in waste hauler and landfill fees, according to Metro Waste.

The Sierra Club opposed the Iowa bill, as well as other attempts across the country to landfill yard wastes. The environmental group argues that methane gas—the byproduct of landfill decomposition—has a greenhouse gas potential that is 20 times greater than the carbon dioxide created through composting.

“Gas collection systems do not capture 100 percent of the methane generated inside a landfill,” according to a statement from the Sierra Club. “Gas collection systems capture only 60 to 90 percent at various times of operation. If yard waste bans were reversed, the amount of methane entering the atmosphere would only increase.”

The Sierra Club also argues that yard waste will accelerate the speed at which landfills are filled and says the best use for yard waste would be through composting, which saves landfill space and serves another purpose.

The Metro Waste study completed by SCS Engineers estimated that overturning the ban and disposing of yard waste in landfills would only decrease the life expectancy of Iowa’s landfills by two years, from 2054 to 2052.

More than 20 states currently ban yard waste from landfills, and most were put in place in the 1990s over fears of shrinking landfill space. A slew of composting facilities were opened, but in recent years there has been a movement to overturn some of those bans. Georgia and Florida repealed their bans within the last few years, and there have been multiple attempts to overturn the yard waste ban in Michigan.

Part of the reason is that the cost of traditional fuels has driven an increased interest in methane, and solid waste disposal facilities are eyes ways to improve methane production methods using landfill gas. But in Michigan, there is another issue. Municipal leaders are struggling to find disposal sites for their yard waste after a number of composting facilities have closed. In Macomb County, plans to open a new composting facility were recently scrapped over fears that a composting center could disrupt plans for future housing developments.

The South Macomb Disposal Authority, which handles waste disposal for five communities within Macomb County, has proposed building a composting facility on a capped landfill but aren’t releasing any specific details yet.

The U.S. Composting Council continues to work against attempts to overturn yard waste bans, and says landfilling yard waste not only increases greenhouse gases, but also wastes resources and reduces recycling efforts. The U.S. Environmental Protection Agency (EPA) has also expressed its support for yard waste bans and continued composting of organic materials.